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Reduced Emissions of TRansport aircraft Operations by Fleetwise Implementation of new Technology

Final Report Summary - RETROFIT (Reduced Emissions of TRansport aircraft Operations by Fleetwise Implementation of new Technology)

Executive Summary:
The RETROFIT project analyses the possibilities and attractiveness of retrofitting new technical solutions, which are developed or available for new aircraft types, into the large existing fleet of commercial aircraft. A new generation of aircraft is only at the horizon. Existing aircraft still have a long life to serve, whereas the operational environment is changing. Airlines are confronted with emission trading, new noise rules, increasing fuel prices, new safety and security demands, a new air traffic management (ATM) environment where older aircraft generally do not comply with the new ATM standards without modifications, and passenger expectations to enjoy the highest levels of comfort possible.
An overview of the project outcome is given which covers stakeholder requirements, technology inventory, airworthiness/certification, integration and technology take up. The project has involved external stakeholders from the aeronautics industry through a workshop. This resulted in an inventory which provides a list of candidate technologies composed of present and future technologies that may be retrofitted to existing aircraft. The inventory was executed in a number of steps, from an Initial Long List, containing a first inventory of candidate technologies to the final version of the Technology Inventor. In the course of setting up the Technology Inventory, recommendations with respect to Research and Technology Development (RTD) for retrofits were collected and experiences with previous (and current) retrofit programs were analysed.

Certification issues have been considered: the final long list of the technology inventory has been reviewed to determine if certification of the proposed changes is feasible (certification guidance available) and if the certification effort becomes a limiting factor.

The project also looked at the cost benefit of a few possible mature retrofit options that were chosen by the team as being worthwhile to investigate further. These were:
• Avionics for SESAR compatibility;
• New high bypass ratio engines to existing A320 aircraft;
• Taxiing by internal power.
The purpose was to investigate if these potential retrofits would be cost effective and could ultimately be attractive for funding entities to support the retrofits. Also the European industrial involvement of these retrofits was studied.

Finally, recommendations are issued.
For the aeronautics sector in general the project recommends:
• to stimulate the air transport sector and the research community to look for retrofit opportunities in view of the extended use of aircraft in the European theatre;
• To stimulate the sector to come forward with new retrofit proposals in the future;
• To stimulate Performance and Improvements Packages initiatives.

As far as research programmes funded by the European Commission are concerned, the project recommends the following:
• to require that any RTD proposal for technology development for new aircraft addresses the potential for retrofit. In promising cases for retrofit the RTD proposal should in addition dedicate a work package to this topic;
• to take specific action to decrease the certification cost and time of retrofits. The high certification cost due to the currently needed repetition of costly tests is preventing the economical application of many new technologies. On the other hand, the recent progress in virtual (that is, software model based) testing reveals a potential to reduce the certification cost of retrofits. It is therefore recommended to stimulate the research on virtual testing and to encourage virtual certification.
• to stimulate the research and development on the specific retrofit topics:
o To incorporate research topics for retrofits in the next call of the RTD Framework program, through feasibility studies ( level 0), maturing promising technologies through Level 1 projects and integrate retrofit technologies in Level 2 projects.
o To demonstrate retrofit technologies in Clean Sky and SESAR.
o To stimulate and facilitate the implementation of retrofits that also benefit societal issues like environmental protection, reduce oil dependency, increase safety and security and ensure mobility by the use of TEN T, structure and regional funds

Details of the RETROFIT project can be found on: http://www.fokkerservices.com/RETROFIT_FP7

Project Context and Objectives:
The orientation phase, WP1 "Product Requirements Identification” identified and provided an initial set of answers to:
• Understand the motives to decisions by the industry to (not) retrofit and (not) to extend the use of older types of aircraft.
• Define categories of industry stakeholders for which retrofit programs are of interest.
• Identify solutions to change the current perception on the subject in favor of extended use of older type of aircraft and commercial benefits of retrofit programs.
• Identify possible areas, which if properly stimulated, can result in retrofit of existing aircraft to meet the industries need,

The inventory phase, WP 2 “Technology Inventory” addressed the analysis of the technical opportunities for retrofitting that new technologies and processes offer. The work package has therefore made an inventory of new technologies and processes, including RTD results obtained from late 5th (Y2001 onwards), 6th and 7th EU Framework Programs and in national programs. In order to direct the inventory towards retrofit applicability the inventory l included an assessment of the potential for application in retrofit programs and of the needs for additional RTD to increase this potential. It has also identifed gaps in the coverage of the aeronautical domain. This has resulted in a long list of potential technologies and processes for use within this project.

In the inventory phase WP3 “Airworthiness and Certification” the certification issues has been identified as they may result from large scale retrofit programs. Development, manufacturing and operation of transport aircraft is fully regulated by the Authorities, via certification standards such as the Federal Aviation Regulations (FAR) as defined by the FAA and Certification Standards (CS) by EASA. Modifications to existing aircraft must be approved either under the existing Type Certificate or under a supplemental Type Certificate (STC). Generally such modifications may also be subject to regulations concerning design, production, maintenance, training and other subjects.

Work package 4 integrated the results obtained in the orientation phase. Requirements from WP1 have been matched to the technological solutions from WP2, taking into account the certification issues from WP3, and leading to the identification of potential retrofit programs. Next the cost-benefit analysis of these programs has been carried out. Most promising programs can then either be ready for technology take-up by the industry, for which the industrial consequences have been analyzed, or may need further RTD to prepare for technology take-up.

The technology take-up phase WP5 “Technology take-up” hasl focused on the factors that will influence the market take up of retrofit projects that have potential positive cost benefit characteristics. It has addressed possible ways in which the European Commission, the EIB, and specific initiatives funded under the auspices of the CIP (Competitivess and Innovation Framework, DG Enterprise), which could stimulate the application of retrofits.
WP5 also addressed broad range dissemination of the projects results to emerging retrofit market stakeholders and potential opportunities for exchange and networking (via established internet professional networks, and the disseminations workshops).

Project Results:
3 Project Requirements Identification
3.1 The definitions
The definition of ‘retrofit’ is:
‘To change the design or the construction, or to include, modify or substitute parts or equipment of aircraft already in operation, in order to incorporate improvements that were not existing, available or used at the time of original manufacture.’
Modifications are defined as changes not covered by the original approved type certificate for the product.
Conversions are a special type of modifications as these change the original role or mission of the aircraft, such as converting passenger aircraft to freighters or aerial tankers, VIP aircraft, patrol or fire fighting aircraft. These types of modifications are not part of the study.
Retrofits are different from Maintenance Repair and Overhaul (MRO) activities, as these involve inspection, maintenance, repair and overhaul of aircraft and aircraft components without including novel parts or modifying the aircraft or its components.
The objective is to define suitable retrofit opportunities within the civil aviation sector by:
• Understanding the rationale behind previous retrofit projects
• Knowing the requirements and the decision factors relevant for future retrofit opportunities
• Identifying future research needs for retrofit technologies
• Identifying suitable (sufficiently mature, available, economically feasible and certifiable) technologies to incorporate in existing civil aircraft
• Performing a cost benefit analysis on these mature technologies
• Addressing certification issues
• Matching the opportunities for funding with European Incentives
• Identifying possible industrial conglomerates/partnership to take up possible retrofit opportunities and the effects on the workforce
3.2 The outcome of the initial questionnaire and workshop
To enable a better understanding of the market place and the drivers for retrofit actions the consortium formulated a questionnaire which was delivered to a representative group of stakeholders. The grouping of questions reflected general, specific and technical aspects of the project.
The following list is a summary of outcome of the questionnaire and the reference group input that was received in a workshop which was set up as an early project activity and held on 2 March 2011. More information about this consultation can be found in Appendix A.

The main conclusions of the initial consultation were:
• Retrofits could increase comfort levels for passengers. Company image can be an important incentive for retrofitting (green image, winglets, CO2 compensation, comfort etc.)
• Within the business segment there is a strong demand for state of the art interiors.
• Reduction of delays could be stimulated; Cost of fuel for holding patterns, shorter turnaround time.
• Problems with existing systems (reliability, maintenance costs etc.) create an incentive to modify or retrofit an aircraft system.
• Return on Investment (ROI) is the main decision factor; uncertainties and long ROI make retrofits unattractive.
• Leased aircraft are less attractive for retrofits as leasing companies often require that the aircraft will be returned to its original configuration and retrofits often benefit the user rather than the owner.
• A role for the EU could be to stimulate retrofits in order to reduce emissions, reduce noise, ensure mobility whilst reducing congestion and create extra high level jobs.

Note: The revenues from an Emission Trading Scheme (ETS) could be used to provide an incentive for “green” retrofits. (The revenue generated by the ETS is delivered directly to the Member States and not centrally distributed.)

• When comparing the large commercial civil market to the defence market several key differences make it more attractive for military aircraft to be retrofitted. (Aircraft lifetime, mission requirements, regulations.)
3.3 Conclusions from the initial stakeholder workshop
Main barriers for retrofits are the non-recurring costs and risks involved accompanied by limited ROI or intangible benefits.
Another barrier is the ownership of the aircraft (leased vs. owned). Aircraft that are owned by airlines are more likely to be retrofitted than the ones that are leased.
In order to overcome the commercial risks a retrofit program should be shared by modifying a larger fleet of aircraft whist retrofit packages need to be optimised to reduce downtime of the aircraft.
From the first analysis of technologies one can see that retrofitting of new or advanced technology engines is seen as a potential on the side of the manufacturers. However airlines and MRO companies are more sceptical due to high risk and cost involved, and to the fact that such programs need to be performed on large fleets instead of individual aircraft. However upgrades of existing engines are seen as more beneficial.
Aerodynamic updates are more widely accepted. New upgrades that have little effect on the existing aircraft structure seem to have the best potential.
Modernizing the cabin is also seen as a potential retrofit activity. Retrofits can be applied when the cabin is refurbished (normally 5 to 7 years) giving 5 or 6 opportunities during the aircraft’s planned useful life.
The use of alternative fuels is only profitable if the price for alternative fuel is lower than kerosene.
Retrofit has the largest potential in advanced equipment solutions, and specifically in the area of ATM compliance
The use of onboard diagnostics systems is generally seen to have a potential for reducing the cost of maintenance and simultaneously increasing reliability (as it should help with quicker troubleshooting and therefore reduces man-hour cost and potentially unnecessary removal of components.) As the spectrum of these types of technologies is wide, the benefits of implementation of these systems are still unclear and the applicability of this technology as a retrofit solution is most likely on component level (for example, included in avionic upgrades).
Regarding passenger connectivity the participants had widespread opinions. Summarizing one can say that this technology will find its way into aviation as requirements for continuous connectivity to the internet. This would result in improved in-flight entertainment capabilities most likely in combination with social media.
Involvement of the Original Equipment Manufacturer (OEM) in retrofit programs is essential as supplier of certified data, certification and configuration management and having the potential to reach a broad customer base. However OEM interests of selling new aircraft are conflicting with investing in older aircraft beyond mandatory requirements.
If there is a good business case there seems to be little need for additional public funding opportunities except for small retrofit batches.
EU funding via the EIB would reduce costs and could act as a catalyst for retrofits assuming that the business case is good.
3.4 Experience with previous retrofit programs
The purpose of the investigation into the experiences with previous retrofit programmes was to obtain insight in the factors and conditions that impact the decisions for executing retrofit activities, in particular for fleet-wide retrofit initiatives (refer to deliverable report D2.3 [D23]).
The investigation into previous retrofit programmes was based on literature found on the internet. Results of retrofit programmes (for example, implementation costs, logistics, operational benefits), whether successful or not, are not made publicly available. The majority of such programmes are either conducted in-house by an airline or OEM, or are a result of private ventures between airline(s) and the retrofit solution provider, and in all cases propriety information is involved. Moreover the project did not include additional financial resources specifically for procurement of costly reports from studies conducted for specific retrofits market segments.
The results of the investigation into previous retrofit programmes consisted of a categorized listing of past and present retrofit programmes and solutions. The investigation could not cover all possible retrofits as the scope would be too broad given the limitations of information that is publicly available. Despite the limitations encountered, results found during the study do lead to an overall positive conclusion.
Retrofits are generally one-off endeavors that are driven by necessity rather than by market competition conditions or strategies for continuous product performance improvement.
However, cases included in the deliverable report D2.3 [D23] indicate that retrofits are carried out more frequently than thought and retrofits are becoming an activity for which the respective needs, business cases and market potential is constantly growing and diversifying. Retrofits are not necessarily targeted to ageing and/or out-of-production aircraft only.
The findings of this study included retrofits in the following categories:
- Avionics
- Engines
- Real-time large-volume data communications for aircraft operational monitoring and safety
- Aircraft cabin modifications and conversions
- In-flight entertainment
- Airframes and structural components (for flight efficiency and drag reduction, retrofits concerning airframe and structural components health (SHM) and usage monitoring (HUMS), and the associated information and communication technology (ICT) and communications capabilities)
From the varying cases over time identified in the study, reasons for aircraft upgrades and modifications vary. However on a top level main reasons and/or incentives include initiatives initiated by mandates (such for engines, avionics) and negative events (aircraft tracking and data communications), keeping the product up-to-date with improvements introduced by OEMs per customer requirements and expectations (increase in functionalities, energy consumption and emissions reduction) or by airlines per passenger requirements and expectations (weight reductions, increased capacity, comfort, connectivity) and rationalization of operational costs (maintenance, repair, reduction of spares count). In addition to the previous there is also an emerging need to retain and modernize certain aircraft types (whether in production or not) to either maintain certain segments and benefits of airlines routes business models (city-pairing, freight) in the face of absence of appropriate contemporary in-production aircraft models vs. older and out-production aircraft models that were designed to do so, or the need for airlines to maintain operational capacity to counter delays in new aircraft deliveries or for deferral of aircraft orders (in times of financial markets strain and reduced access to lending capital).
One of the promising trends that could contribute as a multiplier for access to and expansion of retrofits programs could be in the form of the so-called “Performance Improvements Packages” (PIPs) programs. These refer to programs mainly initiated and carried out by either Engine OEMs or Airframe OEMs or both. In the case for engines these are programs for development and fleet-wide deployment of technical improvement packages for the more popular in-service engines (addressing engine performance improvement per reductions in fuel-burn, emissions, and noise). Such programs are far more numerous than re-engining projects (that are initiated by airframe OEMs) as these do not require structural changes to pylons or wings of in-service aircraft. PIPs are not exclusive to long-time in-service engine models as they are also developed and deployed for clean-sheet aircraft models being delivered now (for example, Boeing B787 and B787-8). With respect to Airframe OEMs, PIP developments encompass a range of changes (including for engines in coop with Engine OEMs) mainly to improve aircraft aerodynamic characteristics to improve or reduce certain operational characteristics (access to airports, reduction of aerodynamic drag thereby increases or reductions in cruise performance, fuel-burn, range, MTOW accordingly) and avionics, as also the product offering in the form of new cabin concepts and cabin systems applicable through retrofit’s. Performance Improvement Packages have and are developed by such Airframe OEMs as Airbus, Boeing, and Bombardier.
Surprisingly, PIPs have been found to not be exclusive only to established Airframe OEMs nor only for contemporary aircraft models, there are also applicable to out-production aircraft models such as in the case of Super98 (USA) that in the past half-decade has been developing and certifying a range of PIPs to revive the DC / MD -series aircraft models as also the out-of-production Boeing B717 and B727–series aircraft models. Such aircraft are in wide use in US markets, and are not fully replaceable by contemporary aircraft models. However PIP development projects have been centered almost exclusively on turbo-fan aircraft models and much less on turbo-prop models for which in the market today only two main Airframe OEMs are present, ATR (EU), Bombardier (CAN). Other than turboprop aircraft models in-service today that are manufactured by ATR and Bombardier, all other in-service turboprop aircraft are no longer in production (for example turboprop aircraft produced by, Fokker, Fairchild, Dornier, Saab), hence retrofit market potentials are evident. The Performance Improvement Package (PIP) scheme could be seen as a blueprint for the creation of retrofit initiatives. The PIP scheme may also be extended to include aircraft systems upgrades or replacements. The PIP scheme may also allow the creation, access, and involvement of groupings (Tier-level suppliers, SMEs, Academic Institutes, Research Establishments) to cooperate or to oversight with OEMs. In this way the PIP scheme would broaden the spectrum of integration and allow for the introduction of newer technologies that are a derivative of long-time RTD initiatives.

4 Technology inventory
In the Technology Inventory a list of candidate technologies was composed of present and future technologies that may be retrofitted to existing aircraft. The inventory was executed in a number of steps, from an Initial Long List containing a first inventory of candidate technologies to the final version of the Technology Inventory as described and included in deliverable report D2.5 [D25]. In the course of setting up the Technology Inventory, recommendations with respect to Research and Technology Development (RTD) for retrofits were collected and experiences with previous (and current) retrofit programs were analysed.
4.1 Technology Long List
First, an Initial Long List of candidate technologies for retrofit was set up. The information about existing and new technologies that are considered for retrofitting presently or in the (near) future was initially collected from various sources, including the RETROFIT project consortium members who participated in successive Framework Programmes, national programmes (as far as available), European FP6 and FP7 projects, and the stakeholder interviews held in January and February 2011. The technologies were categorised according to topics in the following technology categories: Re-engining, Alternative fuels, Aerodynamics, Cabin, Structures, Avionics, Equipment, Security technology, Safety technology, and Other.
The technology inventory was originally set up as an MS Excel sheet of which the information is included in deliverable report D2.1 [D21]. In a schematic overview the detailed information is provided on all technologies, amongst other: specification of technology and relevant issues, Technology Readiness Level (TRL), references and required RTD for application. Each technology has been assessed to see if it provides one of the following benefits:
• Improving basic efficiency of flight;
• Reduction of operational losses;
• Reduction of airport noise;
• Reduction of pollutant emissions;
• Improvement of well-being of passengers;
• Improvement of ATM compatibility.
4.2 Stakeholder workshop
The Initial technology list in report D2.1 [D21] was presented to the participants of the Technology working session of the Reference Group meeting held at Fokker Services in Nieuw-Vennep on 2 March 2011. The working session’s participants were allocated to different teams, with each team supervised by a project partner and comprising a variety of stakeholders.
The participants of the workshop are presented in Appendix A.
The discussion was based on the initial long list of technical possibilities for retrofits as included in deliverable report D2.1 [D21].
The questions posed to the workshop participants were:
1. Which technologies are missing from the list?
2. Indicate in the Initial Long List those technologies that are potentially attractive in the timeframe from now up to 2020.
3. Present the top 5 of most attractive technology items.
Stakeholders, and in particular operators and system manufacturers, see little need for RTD. Manufacturers and MROs see some benefits and needs for specific research in particular areas.
The top 5 of most attractive technology items was:
• Wing tip devices;
• Weight reduction technologies in the cabin;
• In-flight entertainment (IFE) & communications;
• Avionics to improve flight efficiency & for ATM compatibility;
• Compatibility with alternative fuels.
The results of the workshop are reported in the combined project deliverable report D1.3/D2.4 [D13D24]. The Initial Long List was updated with feedback received during the discussions. Among other things, an indication of whether or not the technology is considered as potentially attractive by the stakeholders was added as a new property for each technology in the long list.
The team concluded that:
- The development of wing tip devices that would not require structural modifications to the aircraft wings would be an interesting RTD topic.
- Cabin weight reduction will use technologies that are already developed for new aircraft and interiors.
- IFE and communications can be derived from technologies developed for new aircraft. The integration into older aircraft needs attention however.
- Avionics for ATM compatibility should be investigated.
- Alternative fuels need demonstrations to test the long term effects on engines.
The long list was updated with the information collected during the workshop and the analysis of experiences with previous (and current) retrofit programs. As the initial long list is very extensive, a more concise variant was abstracted containing the most relevant technologies. This final long list is included in deliverable report D2.5 [D25].
4.3 Recommendations and short list for RTD activities
General recommendations with respect to Research and Technology Development (RTD) for retrofits include
• Research in particular areas;
• System or component integration into older, existing aircraft;
• Validation and demonstration;
• Long-term impact on technology and maintenance, and certification of retrofits (for example, allowing simulations for small retrofits).
Furthermore, it is recommended to include retrofit aspects in RTD programs, including integration / interfacing aspects of the new technologies in existing aircraft.
To prepare the recommendations for the European Commission, additional analysis was carried out by the consortium. The summary of RTD topics was updated with latest insight and analysed in a consortium meeting to develop a short list of RTD needs considering such issues as contents, relevance for the market, technological feasibility and the extent and kind of RTD needed.
The TRL levels in this table are the technology readiness levels from the point of view of retrofit application. Such a TRL level can be quite different from the TRL level of the same technology for application in new aircraft. For example major integration issues in existing aircraft lead to a TRL level of at most 4 from retrofit point of view.
The TRL levels are further explained and amplified in the “Report on initial long list” which is to be found in retrofit deliverable D2.1 [D21].
To give an insight as to the “Type of EC project” more information is explained in the executive summary.
The analysis resulted in the recommendation for the EC to stimulate the research and technology demonstration on the following 10 retrofit topics (refer to deliverable report D2.2 [D22]):
Technology TRL Level RTD Required
Type of EC project
Cost-efficient implementation of Single European Sky ATM Research requirements (SESAR) on existing aircraft, for example, through a validated and certifiable uniform SESAR box to be interfaced with existing avionics suites. 1 or 2 YES
Level 0/1
Feasibility and implementation of advanced, stand-alone (i.e. not tied into main avionics) Health and Usage Monitoring Systems (HUMS) for structures and none-critical systems on existing aircraft, supported by RTD on air-ground communication and more advanced data communication (integrated data-power, wireless transmission) in existing aircraft. 3 YES
Level 1
Wireless data communication in existing aircraft for integrated configurable network solutions for, for example, advanced In-Flight Entertainment and Connectivity, cabin management and safety. 3 or 4 YES
Level 2
Air-ground and at-gate communication in existing aircraft, for example, for Advanced Health and Usage Monitoring System (AHUMS), black boxes, turn-around operations, connectivity with maintenance base and IRU fault detection. 3 or 4 YES
Level 1
Engine systems and components retrofit development, rig testing, demonstration, and flight qualification such as combustion chamber retrofit for Nitrogen Oxide reduction. 4 YES
Clean Sky
Development of a retrofit kit for nacelle and composite fan casing, for weight reduction, aerodynamics benefits (laminar flow) and potentially also reduction of noise. 4 YES
Clean Sky
The long term performance of alternative, non-drop-in fuels (incl. synthetic fuel and biofuel) in existing engines without (major) modifications on existing aircraft, such as the effect on the gas path, the effect on the engine maintenance on the long term, and the effect on the engine washing. 3 YES
Clean Sky
Integration and validation of new parts for the exchange of secondary structures by composite parts, for weight reduction and other structural benefits. 3 Yes
Feasibility of a glass cockpit replacing analogue instruments in existing aircraft. (because of the differences in avionics and generic FMS applications the design and development is often per type for small / medium operators) Per type Yes
Per Type
Alternatives to main engine based taxiing for existing aircraft, such as taxiing on internal power using electric motors in the main undercarriage, to allow main engines on idle setting or switched off during taxiing. 4 Possibly
Clean Sky
5 Airworthiness and Certification
The final long list of the technology inventory has been reviewed to determine if certification of the proposed changes is feasible (certification guidance available) and if the certification effort becomes a limiting factor. The objective of the task number 3 was to provide an overview of the certification implications of the new technologies as presented in the technology inventory.
In deliverable report D3.1 [D31] the certification implications were discussed for each group of technologies from the technology inventory by identifying and describing aspects that may play a role in certification. (The extent of these aspects only becomes clear in an actual certification process.) Additionally several specific technologies were evaluated in order to provide an impression of certification issues that could exist.
It must be noted that it is difficult to give definite information about certification of certain technologies in a generic way. Certification of technologies is an interactive process with the certification authorities and the real extent of the effort can only be defined when the actual certification process is actually initiated and all details are known.
All proposed changes can be certified. An important question in the retrofit perspective is at what cost a change can be certified. Some of the proposal for “re-engining” will result in classification as a substantial change. For a substantial change a new Type Certificate must be applied for and the whole aircraft certification must be redone. In view of the certification cost involved it is highly unlike that a substantial change will be performed.
The discussed technologies are wide spread so that an accurate impact of the certification effort cannot be made. For this reason the certification chapters provided in the report are high level and generic. In addition it must be noted that a certification applicant can propose a certification plan, but final approval is provided by EASA. This means that the exact certification effort can only be established after agreement of the certification plan by EASA.
Even when EASA approves a certification plan then it is still possible that during the certification EASA requires compliance with additional certification requirements. This can happen when an accident investigation uncovers an unsafe condition.
In discussions with stakeholders it was stressed that the certification of retrofits is expensive and time consuming. It was suggested that the certification process could be shortened if EASA would apply procedures as used by the FAA. It was also suggested that certification could be quicker and more cost effective if the retrofits were to be certified by the OEMs. This would prevent a situation whereby individual retrofit providers need to certify retrofits on their own, leading to multiple certifications. If the OEMs would be more active in retrofits, time and cost could be saved. However in most cases the OEMs are focusing on new product development. Good experience has been gained with upgrades that for example Boeing developed for its products.

To explain the technology and the maturity thereof it was decided to include extra information with regards to the expected certification category the scale of usage up until now and also the need for further research and development.
The following EASA classifications exist:
• Substantial change;
• Significant change;
• Non-significant change.
The non-significant changes can be subdivided in major and minor changes.
A substantial change is a product level design change which is so extensive that a substantially complete investigation of compliance with the applicable requirements is required, and consequently a new type-certificate has to be applied for. A significant change is a product level change to the type-certificate to the extent that it changes the general configuration or the principles of construction are not retained or the assumptions used for the certification of the product to be changed do not remain valid, but not to the extend to be considered a substantial change.
For a substantial change the latest requirements must be used during the certification of the change. Both for the by the change affected areas as well as unaffected areas.
For a significant change the areas affected by the change need to comply with the latest certification requirements.

6 Integration
The project looked at the cost benefit of a few possible mature retrofit options that were chosen by the team as being worthwhile to investigate further. The purpose was to investigate if these potential retrofits would be cost effective and could ultimately be attractive for funding entities to support the retrofits. Also the European industrial involvement of these retrofits was studied.
In the deliverable report D4.1 [D41] a schematic overview of all technologies and the evaluation aspects is provided. Currently the main drivers are re-engining projects and winglet/sharklet programmes. Alternative fuel (bio-fuel) is a definite future technology that is being promoted by the European Union. Drop-in fuels do not require any retrofit and are therefore outside the scope of the study. Alternative fuel, including bio-fuel, is a retrofit technology whenever the alternative fuel is non-drop-in fuel.
Support and assistance to third world countries to replace old aircraft by modern aircraft could possibly be provided as a form of development aid or an initiative from the European Investment Bank. The employment in European MRO companies could receive a major boost by being part of consortia preparing and performing the retrofit work to make the aircraft conform to the service standards.
6.1 Proposals for Cost Benefit Analysis
In order to choose three mature retrofit candidates a proposal was made by the lead contractor and agreed upon by the members of the consortium. All retrofits were considered including the ones listed in Table . The table represents the choice of the consortium members made during work package 4 and explained in the deliverable report D4.1 [D41].

Technology EASA Classification Usage RTD Required
Replace whole engines with new ones; Significant Large scale No
Combustor / high pressure system performance and durability upgrade; (if thrust increases by more than 10% classed as significant) Significant Large scale Yes
Alternate fuels, not considered a retrofit by the consortium; (non-significant unless composition of fuel changes or thrust is increased above 10%) Non significant Trial stage Yes
Nacelle serrated trailing edges; Non significant Small scale Yes
Active or passive suction laminar flow; Significant Under development and trial stage Yes
Winglets / Sharklets for Boeing 737, Airbus A320; Significant Large scale PIP program Yes
Riblets in paint surface and other drag reducing coatings; Non significant Small or Large scale No
Zonal dryers; Non significant Large scale No
Exchange of secondary structures by composite parts for weight reduction; Non significant Small scale Limited
Cabin Operation, Functioning, Safety Network and Cabin Management System (hard lined or wireless); Non significant Trial stage Yes
In flight or on ground Advanced Health and Usage Monitoring Systems; Non significant Under development and trial stage Yes
Flight Data Management monitoring & improvement: Advanced flight data analysis; Non significant Trial stage Yes
Upgraded Flight Management System to meet SESAR requirements; (Normally cockpit upgrades are considered Non Significant). (Non) Significant Under development Yes
Taxi with internal power; (main undercarriage) Non significant Under development and prototype tests Yes
Lithium batteries for secondary power; Non significant Trial stage Yes
The Shear Thickening Fluid luggage Fly bag; Non significant Experimental Yes
Automatic Fire Suppression System; Non significant Large scale No
Lightweight surveillance system for cockpit access, cabin or cargo surveillance; Non significant Small scale No
Table 1: Retrofit technologies chosen by the consortium members of the RETROFIT project

As resources and time were limited it was decided that three potential mature retrofits would be subject of a cost-benefit analysis. The agreed technologies for cost-benefit analysis in Task 4.2 were:

• Avionics for SESAR compatibility
Reasoning: If only new aircraft would be adapted for the future SESAR ATM concept the full benefit will only be achieved when much of the current fleet in Europe would be replaced. This could take 30 years or more. With retrofitting the benefits for the community will be available much earlier. The team proposed to investigate the attractiveness of a newly developed SESAR box.

• New high bypass ratio engines to existing A320 aircraft
Reasoning: the A320 is one of the most numerous narrow body aircraft, burning a large fraction of the air transport fuel. The A320 NEO is developed using the latest state of the art Pratt & Whitney and General Electric engines. These promise a fuel saving of between 10 to 15% per flight, which will have a large economic and environmental benefit. Assuming Airbus involvement, a relatively low threshold retrofit programme could be accomplished.
• Taxiing by internal power
Reasoning: although the actual cost gain per aircraft movement will be relatively small, the accumulated benefits can be significant for the European and global air transport industry. This particular study is interesting because it involves benefits for the operators, benefits for the airports and benefits for the community as a whole.

Cost benefit of avionics retrofit for SESAR compatibility
The benefits of the SESAR ATM system for the operators and the European Community are dependent on the number of aircraft equipped with a compatible avionics system (navigation and communication). Currently delivered aircraft are already largely compatible (forward fit). However, most aircraft of the existing fleet are not SESAR compatible, and these are expected to remain in service for several more years or even decades.
Retrofitting existing aircraft with SESAR compatible avionics would enable the operators and the European Union to benefit much earlier from the potential SESAR benefits.
It is assumed for this cost benefit analysis that the ground infrastructure will be in place for SESAR and that a uniform SESAR avionics box could be developed and installed as soon as the SESAR ATC system becomes fully operational. It is therefore assumed that a generic unit will be developed which encompasses all capabilities required for SESAR compatibility. This is basically communication (digital upload and download), connection to the SWIM database and 4D navigation based on GNSS. For individual aircraft types different interface modules would need to be developed as an add-on device. It is assumed that for competitive reasons two manufacturers will independently develop and sell such a unit.
This study has been executed with simple financial models, with many assumptions concerning the fuel price, ETS charges and the future European financial situation. The results should therefore not be seen as absolute, but as indicative.
The assumptions and analysis applied are described in detail in deliverable report D4.2 [D42]. The cost benefit analysis was limited to 50% of the European A320 and B737 fleet. It assumed that 2000 aircraft would be retrofitted.
Figure shows the results, expressed as a payback time for the investment per aircraft by the operator, based on 2000 retrofits.

Figure 1: Payback time vs. aircraft conversion time dependent on average time savings

The Retrofit consortium analyzed the potential time benefit resulting from SESAR ATC. This would result in a 2.5 minute/ flight gain due to delay free flight and a 2.5 minute/ flight gain due to direct routing. (Note that other Single European Sky (SES) elements such as the unification of the European airspace and the use of military airspace by civil airlines will have an additional time benefit of up to 9 minutes). The investment in equipment and the cost of installing the SESAR box is estimated at 1.250.000€ per aircraft. Comparing a 5 minute gain in time and an investment of 1.250K€ would result in a payback period of a little over 2 years, again assuming that the SESAR box is feasible, the SESAR ATC system would be fully operational and investments in ground infrastructure is fully synchronized.

Table 2 provides the calculation for the community benefits, dependent on the number of aircraft converted and the time saved per flight, taking 1354 flights per year per converted aircraft.

Table 2: Community benefit of retrofit for SESAR compatibility under different assumptions

A realistic scenario, with 2000 aircraft converted and 5 minutes time saving per flight yields an overall benefit of about 1.3 billion€ per year for the European Community.
A business case would be dependent on the synchronous implementation of the SESAR ATC system, the large sales volume, the cost of developing the SESAR Box unit and the cost of interfaces for the different aircraft. As the total volume of available aircraft is realistically limited to about 2000 and more than one supplier may be in this market, the costs should be recouped and a profit realised with a market share of well below 1000 units. If the market expected is much smaller the price to be charged for a conversion would increase rapidly. Especially the timely availability of the total benefits of the SESAR system poses a substantial risk.

Cost benefit of re-engining the A320 family
The A320 is one of the most numerous narrow body aircraft, burning a large fraction of the air transport fuel. The A320 NEO will be developed by Airbus Industries to use the latest state of the art Pratt&Whitney (P&W) and General Electric (GE)/Snecma engines. This promises a fuel saving of between 10 to 15% per flight, which will have a large economic and environmental benefit.
Currently several thousands of A320 family aircraft are in service, re-engining these with the new engines like foreseen for the NEO could result in a very large fuel and emission reduction. Assuming Airbus involvement, a relatively low threshold retrofit programme could be envisaged, where new engines are retrofitted to a significant percentage of the fleet of existing A320 aircraft.
For the retrofit case only the A319, the A320 and the A321 were considered. The cost benefit analysis is generally based on re-engining with the P&W GTF engine, but the numbers will be comparable when using the GE/Snecma Leap-X engine
The assumptions and analysis applied are described in detail in deliverable report D4.2 [D42].
The results of the analysis performed are presented below. Table 3: summarizes the savings assumed, based on an improvement of 12% on fuel consumption:

Table 3: Operator benefits of re-engining

Table 4 summarizes the operator capital cost for re-engining

Table 4: Operator capital related costs due to re-engining

The societal benefits of re-engining would exist in terms of emissions and noise reduction.

Table 8: reduction of external costs

The analysis suggests that re-engining will not result in a good business case for the operator and the suppliers if no more than 2000 aircraft would be converted. Calculations show that for a sufficiently attractive ROI, the fuel efficiency improvement should be more than 20% unless other cost benefits are identified (such as maintenance costs).

Cost benefit of electrically powered taxiing
Conventional aircraft use the power of their main engines to taxi. However, the main engines of typical commercial aircraft are very inefficient and polluting in this kind of operation, because of the low thrust levels involved. In many cases the aircraft speed is controlled by braking as the idle thrust of the engines is too high. This leads to additional brake wear. Therefore, alternative means to propel the aircraft on the ground are researched by the industry.
This study treats the possible benefits with regard to emissions of taxiing on electrical power generated by the auxiliary power unit (APU). The assumptions and analysis applied are described in detail in deliverable report D4.2 [D42].
The cost savings are based on a fuel price of €1/kg and an Emission Certificate market price of €15/tonne CO2. Costs incurred by the operator are mostly the purchasing costs of the equipment. The effect on maintenance, training and gate pushback costs have been ignored as they consist of a large number of relatively small contributions, dependent on the particular circumstances at each airport. No additional financing costs are assumed.
Data are calculated for 3 types of aircraft assuming that electrical power is used during a large portion of the taxi time.
B737 series A320 series A330 series
Fuel quantity savings/trip (kg) 247 215 631
CO2 quantity savings/trip (kg) 777 676 1989
Fuel cost savings/trip (€) 247 215 631
Emission certificate savings/trip (€) 12 10 30
Cost savings/trip (€) 258 225 661
Trips/year 1249 1301 904
Cost savings/year (Mil€) 0.323 0.293 0.598
Table 6: Cost savings per year to the operator

Assuming a ‘reasonable time frame’ to break-even to be 3 years or less, this allows an maximum acquisition price to the operator of about 1 M€ per aircraft for the B737 and A320 series and about 2 M€ for the A330 series. These prices seem to be well feasible. The feedback from one manufacturer of electric wheel tugs demonstrated that the calculations by the Retrofit team were consistent with the calculations made by that commercial company.
The potential external cost benefits of modifying all jets in the narrow body group could amount to 237 M€ per year.
It is concluded that electric taxiing may well be cost effective on its own economic merits for the European airlines, and provide a business case also to the suppliers for such equipment.
However the ROI period is quite long. Large scale introduction would provide sizeable benefits due to lower acquisition costs and for the European society.
6.2 Industrial Consequences
It can be imagined that a consortium with OEM support will have a lower risk profile than a consortium that has little or no support from an OEM. In this section the following criteria are evaluated for each of the three technologies and for each of the three consortium types in order to be able to indicate industrial potential and potential issues involved.
It is likely that no large scale retrofit programs will be undertaken by a single company. It is expected that to spread risks and to combine multidisciplinary capabilities consortia will be formed. This will ensure that the capabilities and capacities of various parties are combined to produce an acceptable end product.
For each conceivable retrofit program there will be a different consortium possible, both in capabilities and in individual companies and, the legal requirements for the consortia are in essence exactly the same.
For the 3 possible retrofit programmes as identified in the deliverable report D4.2 [D42], an initial overview of possible consortia has be identified at a high abstraction level. The possible consortia combinations are, while not endless, extensive and show the expertise in the European aviation sector in the fields of Design, Supplemental Type Certificate (STC) and MRO.
Three different consortia are identified:
- Consortium 01: including the following: OEM & TCH airframe, OEM Engine or OEM System and a MRO organisation.
- Consortium 02 including the following: STC organisation, OEM Engine or OEM system. MRO organisation. No or limited support from OEM & TCH airframe.
- Consortium 03 including the following: STC organisation, MRO organisation. No or limited support from OEMs. An important element of this study is the ‘Fleet wise Implementation of Technology’. In view of the important role of capacity for fleet wise implementation, the constitution of the consortium is important.
Based on generic consortia the following risk aspects are analyzed. More details about the approach and the retrofit actions and the generic consortia can be found in deliverable report D4.3 [D43].

Risks of consortia
Six different criteria were analysed to show the requirements and associated risks for the 3 types of consortia. The results of the risks for each combination are shown in Table where the risks are indicated to be low, moderate or high.

RETROFITTING
Minimum expected airworthiness requirements Risks
Consortia Certification Showing compliance to the requirements 1 Capacity 2 Capabilities 3 Location 4 Commercial 5 Environmental 6 EU Support
Avionics for SESAR compatibility
1 OEM OEM low low low high low high
2 Partial OEM Partial OEM mod mod low high low high
3 No OEM No OEM high high low high low high
New high bypass ratio engines to existing A320 aircraft.
1 OEM OEM low low low high low high
2 Partial OEM Partial OEM mod mod low high low high
3 No OEM No OEM high high low high low high
Taxiing by internal power.
1 OEM OEM low low low low low mod
2 Partial OEM Partial OEM mod mod low mod low mod
3 No OEM No OEM mod mod low mod low mod
Table 7: Consortium risk overview
Besides capabilities specifically needed for the retrofit programme at hand also general capabilities for co-operation in a consortium are needed such as an open mind to innovation and a drive to support existing aircraft to continue their competitive operation. Important aspects are the ‘Integrator’ knowledge and capabilities. These are present at the OEM therefore consortia risks are very dependent on OEM involvement. Besides information required on an aircraft configuration the key capability is the presence of ‘Design Organization Approval’ in a company or consortium. Companies that have a DOA on a large range of fields are more capable of applying extensive retrofits. Retrofitting engines by a consortium type 3 is regarded as commercially impossible due to lack of specifications of the baseline configuration.

Conclusions
The three retrofit actions chosen for cost-benefit analysis in deliverable report D4.2 [D42] gave an indication that the various aspects regarding retrofit are not easy bedfellows.
Fleet-wise retrofit programmes need to be undertaken by consortia to spread risks and to provide sufficient capacity. Three types of consortia have been studied: consortia with only STC and MRO organisations, consortia extended with engine and system suppliers, and consortia further extended with aircraft manufacturers. The risk elements for the consortia to undertake a retrofit programme have been identified.
The risk has been analysed on the three retrofit programmes that had been selected previously:
- avionics for SESAR compatibility
- new high bypass ratio engines to existing A320 aircraft
- taxiing by internal power
Overall it can be said that risk in terms of capacity and capabilities are strongly dependent on the type of consortium and the amount of support of OEMs. Location risks do not seem to be an issue for any consortium; however it will be a point of attention in the initiation of a retrofit project. .
For the three retrofit programmes investigated the specific conclusions are as follows.
For the new high by pass ratio engines to existing A320 aircraft retrofit program it is concluded that from a commercial perspective the consortium needs to include at least the engine suppliers. Even if the aircraft manufacturers are in the consortium the commercial risk is high.
For the avionics for SESAR compatibility retrofit programme the commercial risk is high. Support from avionics system suppliers and aircraft manufacturers would increase the capabilities of the consortium. The consortium should be large enough to provide sufficient capacity for fleet wise implementation.
For the taxiing by internal power retrofit programme the commercial risk is moderate and even low when the aircraft manufacturers are part of the consortium. Capacities and capabilities of the consortium are at most moderately critical and even low when the aircraft manufacturer is involved.
6.3 Workforce related to the three retrofit technologies
In order to assess the consequences for the employment in the European industry, an assessment was done on the number of jobs that the three retrofit programs would create.
Apart from a direct effect of employment in the manufacturing and MRO industry, there would be additional employment in the European society due to indirect and induced effects. Oxford Economic Forecasting is using a multiplier of 3.26 for these effects.
A very rough estimate of the effects on employment would result in the following data:
1. SESAR equipment retrofits would cost € 1.250.000 per aircraft, of which 1,1 million relates to the equipment and € 100.000 for the installation effort. Assuming 2000 aircraft would be retrofitted, the total investment would be € 2.5 billion. It has been estimated that the investment in SESAR will create 42.000 additional jobs in the major air transport industries. Employment created by the indirect and induced impacts of SESAR would add another 116.000 and 170.000 jobs respectively, taking the overall job creation generated by SESAR to an estimated 328.000 (refer to the McKinsey report on SESAR: http://www.sesarju.eu/news-press/news/new-macroeconomic-study-sesar-mckinsey-873. Assuming that half of these jobs would be created in Europe, the retrofit would create more than 21.000 new jobs in the major European air transport industries and 164.000 new European jobs overall.

2. The new engine would cost about € 10.5 million per engine. If a program is started for 2000 aircraft, the purchasing discount could be as much as 35%. The total investment would be € 4.78 million per engine. It is assumed that conversion cost would be € 0.61 million per aircraft. Total investments would therefore be € 10.2 million per aircraft. Assuming that 2000 aircraft are modified, the total value of retrofits would be € 20.4 billion. Assuming a ratio of 17 jobs per € 1 million, the investment would lead to the creation of 346.800 jobs. Again assuming that 50% would be realized in Europe, the direct jobs created in Europe would be in the order of 173.000. The indirect and induced jobs would be in the order of 560.000 jobs.
3. Assuming a € 1 million investment for the electric drive for an A320 type of aircraft and a € 2 million investment for an A330 type of aircraft, whilst 2000 narrow body aircraft and 200 wide bodies would be retrofitted, the total investment would be in the order of €2.4 billion.
Again assuming that 50% of the benefits would be realized in Europe, a total of 20.000 jobs could be added. Indirect and induced effects would result in an additional 66.000 jobs.
These calculations show that these programs would enable an increase of the highly skilled workforce in Europe of considerable size.
7 RTD funding and Technology take up
The technology take up issue is discussed in the elaborate deliverable report D5.1 [D51].
The RETROFIT study has also considered the role that European Commission funded programs could play in the area of retrofits. Basically two roles can be distinguished: stimulating research and technology development and the role of stimulating implementations of retrofits.
The reasons for market intervention by the Commission have to be linked to the European policies:
- ensuring mobility,
- enabling a strong industrial base and growth in jobs, assist in solving market failures
- protecting the environment,
- improving safety and security and setting world standards
- reduce the dependence on oil derivatives etc.

7.1 Support for RTD
The Commission Framework Program supports RTD on a European scale. Up to now an air transport and aeronautics focus exists in the transport program. Specific RTD actions for retrofits could be supported under this scheme if the Commission policies will benefit from such actions.
The RETROFIT project has identified RTD topics that are unique for retrofitting and strengthen European policies as listed above. These 10 technology areas are mentioned in the short list.
Support for these RTD activities could range from level 1 to level 3 projects.
Feasibility of retrofit solutions can be investigated in Level 0 projects. The proposed SESAR box could be a good example of a feasibility study to investigate if such a solution would be possible.
Funding for specific retrofit technologies and related certification that cannot be derived from RTD for new product development could be realized via Level 1 projects of the Framework Program. The advantage of doing this research in a European setting is that the work will attract the best capabilities in Europe. The Framework program will also allow SMEs that are normally not integrated in the supply chains of the OEMs and SMEs that focus on retrofits or focus on out of production parts, to participate in the European research. Focus in the last call of FP 7 could be on clever HUMS systems, smart logistics for retrofits, virtual certification, customization of cabins etc. As became already apparent in the workshops with the stakeholders, many see the need for integration activities as a major challenge to integrate new technologies into existing aircraft and their systems. Therefore specific Level 2 projects could address the integration of retrofit technologies in existing systems. This refers to basically all 10 proposed retrofit technologies.
In the last call of FP7 the Commission intends to call for Level 2 projects that have a direct impact on retrofits. It is the intention to call for a Level 2 project for large scale demonstration of extended distributed modular electronics, seamless aeronautical networking through integration of data links, radio's and antennas as well as for integrated environment for optimized airline maintenance and operations.
It is recommended that the topics in the call will also address the issue of retrofits in these domains.

The Level 3 project Clean Sky already addresses the demonstrations to integrate modifications to existing engines. If the market requires a qualification and quantification of the benefits of retrofits, the Commission may consider using Level 3 activities within Clean Sky to prove the benefits of applying specific retrofits to potential customers.
As Clean Sky is heavily focused on greening, retrofits for engines, composite parts, alternative fuels and electric taxi could be part of the (future) Clean Sky program. If other Level 3 projects would be started in the next Framework program (Horizon 2020), cabin data communication as well as air ground communication and retrofitted HUMS systems could be demonstrated as well.
SESAR is another Level 3 demonstration project. The added value of integration of novel equipment in existing fleets to become SESAR compatible, the SESAR Box proposed, is to be demonstrated in SESAR.

7.2 Support for certification
From the interviews during the project it became clear that the time and cost of certification is a potential barrier to the application of retrofits. It is recommended that the Commission urges EASA to simplify the procedures so that retrofits once developed can be implemented as soon as possible. Already in the new ACARE Strategic Research and Innovation Agenda the issue is addressed as well. New simulation tools can help to shorten the certification process and lower the cost. This is of particular interest in retrofits as promising retrofits will bring quick gains to the industry and the society at large.

7.3 Support for near term retrofit opportunities
The Retrofit project contacted the Commission (DG Move), SESAR, the EIB, a commercial bank and a financial investor to discuss the outcomes of the project. The outcome of the discussions is as follows:

Outcome of discussion on the electric taxi proposal.
The financial market sees this as a possibility as the benefits are clear and related to a single entity. Although the Return on Investment period would be quite long, the direct and intangible benefits make it a proposition that would be worthwhile to further investigate. Perhaps some sort of stimulus from the European Commission in view of the environmental gains could expedite the introduction of such a system. This stimulus could be in the form of soft loans.
One supplier of electric taxi equipment offers the equipment on a monthly lease basis. The ownership remains with the manufacturer. This financial scheme increases the attractiveness especially for leasing companies.
Respondents made it clear that the taxi system should be fail safe. Any malfunction should not result in blocking runways or airports. The risk of adding yet another system to an aircraft should be mitigated.
One suggestion was to combine the electric taxi with electric braking and use KERS energy to taxi. Although this looks like a promising approach, the combination would multiply the potential problems and prevent an early application of electric taxi in the fleet. Already several companies, including companies in Europe, are developing the electric taxi systems. It would be appropriate to demonstrate the retrofit of the new taxi system for the main gear in Clean Sky as the system will bring benefits to the environmental protection.
In conclusion the electric taxi is seen as a promising candidate for retrofits, especially if some incentive by the European Commission could be provided.

Outcome of discussion on the The re-engining proposal
The financial market agrees to the conclusion that the current proposal is not attractive. The improvement needs to be in the order of 20% fuel reduction to be justified, or the number of aircraft retrofitted with new engines needs to be substantially larger thereby reducing the fixed cost further. This would require a joint action by Airbus and Boeing which would damage the sale of new aircraft that are already fitted with new engines.
The bank consulted noted however that older aircraft are more difficult to sell on the world market as the BRIC countries (Brazil, Russia, India and China) are developing new aircraft that can compete with modern Western technology. As a result, western airlines may be forced to use their aircraft longer than in the past. This could make retrofitting of new engines attractive. If the European Union would support this retrofit in view of the positive effects on the environment, for example to subsidize the difference between cost and benefits, the retrofit could become attractive.
Banks stipulated that - as with all major retrofits - the ownership of aircraft is a major issue.
All agree that this retrofit cannot be done without the full support of the aircraft and engine OEM.

Outcome of discussion on the the SESAR retrofit
By far the most difficult issue is the retrofit for SESAR compliance.
The commercial banks and investor stated that there is no interest in funding these retrofits as the benefits are not clear and will not be easily traced to the aircraft operator whilst the risks are very high. Even if aircraft are well equipped there is no assurance that the ground infrastructure will be ready as well. So basically there is no interest in the financial market. SESAR is viewed as a political program not as a business case.
The uncertainty of benefits is also recognized in the USA. There is strong opposition against NEXTGEN investments in the USA as the benefits for the commercial operators are uncertain and the benefits for general aviation and the military are nil, although they also need to procure ADSB and other equipment. In order to speed up the investments at airlines, the FAA is developing a best equipped, best served model, although the details are still unclear. Also the FAA together with an investment company developed the idea of an equipage fund. This fund would buy NEXTGEN equipment and lease it to operators. It would receive support by the FAA and could attract private capital.
DG Move stated that the equipage fund will not be implemented as private investors and industries would no longer be willing to participate. That would leave the FAA as the sole funding source, but the FAA seems not to have the money to enable the fund. Besides, the expert in the EIB explained that ATM equipment will be fully integrated in the avionics of the aircraft and thus cannot be leased as a separate item.
The Commission cannot afford SESAR to fail. It has therefore already claimed € 3 billion for investments but these would probably be needed for ground infrastructures. It also has made data links mandatory by 2013 (CPDLC). It also looks at ways to stimulate the technology take up. One idea is to provide loans to operators to buy the equipment needed. These loans would cover 50% of the cost. However the operators would not be obliged to pay interest as long as the SESAR system is not operational. The interest due would be subsidized by the Commission for a few years after which Member States would need to subsidize the interest until the SESAR system is declared operational (the transition point). These loans would need to be provided by the European Investment Bank whilst interest would be paid from TEN T funds.
However there is a problem with subsidizing as this would be in conflict to GATT regulations.
SESAR stated that the Return on Investment period would be quite long (up to 12 years) as the equipment would be procured piecemeal in time.
The expert at the EIB was quite critical on the SESAR developments. He stated that ATM developments will be dictated by the USA rather than Europe. There needs to be much more development before the SESAR technologies are mature and can be demonstrated. This is true in particular for the SWIM data and data link.
In his view the Commission should provide system benefits if it makes certain equipment mandatory. Looking at the USA, the compensation could be to provide free ATM services and SWIM services. He also stressed that a single SESAR Box would be impossible as equipment differs from aircraft to aircraft and the retrofits need to be integrated in the existing on board systems. He stressed that more work is needed to understand the type of equipment needed for SESAR. It would be too early to decide now and the cost of equipage could prove to be substantially lower than currently estimated. Also he argued that the Commission should be vigilant that the manufacturing industry would not make the equipment too expensive by adding unneeded functionalities in case the equipment would be subsidized. In conclusion he feels that it is too early to decide on any retrofits related to SESAR.

In conclusion it seems that:
- there are serious doubts if a SESAR Box as proposed in the RETROFIT project can work. A feasibility study is recommended to be done as a Level 0 project in Framework 7.
- there are too many uncertainties to start retrofits at this point of time.
- better understanding of the equipment required for SESAR is needed before investments can be made. This could also lead to lower investment costs.
- if the Commission decides to make equipment mandatory it should compensate the cost by providing funding or other benefits.
- if equipment needs to be procured on a voluntary basis, financial incentives are needed to reduce the risks. But financial incentives may not be sufficient and additional benefits should be provided.
- incentives cannot be provided to European operators alone. Therefore Europe has to start a global ATM approach.
- the financial world is not interested in investments related to SESAR.
8 Final Workshop
The final workshop held at NLR on February 14, 2012 was attended by a representative group of aviation specialties and specialists; the EC was represented along with a Dutch government (“Agentschap NL”) representative.
8.1 Presentations by the RETROFIT consortium members
Coordinator of the RETROFIT project Martin Knegt welcomed all of the participants and thanked everyone for taking the time to attend.
Next, he provided a summary of the project dwelling on some of the highpoints and informing the workshop about the chronology of the project, from the initiation through to the request for extension submitted in September 2011 and honored by the EC
The workshop proceeded with the following presentations by the various consortium partners:
1. Harry Tsahalis on “Investigation on Previous Retrofits”, about experience with previous retrofit programs, cases and findings.
2. Erik Baalbergen on “Technology Inventory and Recommended RTD Topics”, followed by discussion on retrofit RTD topics recommended to the European Commission.
3. Dave Chilton on “RETROFIT possible future programs”, presenting a selection of potential retrofit technologies.
4. (intermezzo) Jan Vana from Wheeltug about an onboard system that moves aircraft on the ground using electric motors attached to the nose wheel, as an example of a retrofit for emission reduction.
5. Evert Jesse on “Cost-benefit studies”, analysing the cost / benefits of SESAR compatibility retrofits, Retrofitting existing A320 aircraft with GTF/NextGen Engines.
6. (intermezzo) Tom Milder from Fokker Services on “Modifications”, presenting examples in the areas of GNSS, seats, LED lighting, ADSB-out, and the iPad® Class 2b electronic flight bag.
7. Ad de Graaff on “RTD funding and Technology take up”, discussing possible public funding support.

8.2 Questions and answers
A plenary open forum with discussion on the three Cost-benefit cases and public funding resulted in a series of questions and answers summarised here below.

8.3 Cost benefit considerations
It was understood that the cost benefit considerations used as examples were never meant to represent an extensive analysis that covered all of the facets of a retrofit modification. However the comparison between the retrofit calculations on electric taxi and the business case presented by a manufacturer of the device showed a good similarity.
It was agreed that the consortium had done a good job in identifying and illustrating the possible development fields of retrofit technology along with the research into previous retrofit projects and results (refer to deliverable report D2.3 [D23]).

8.4 Points of discussion
During the discussions there were three main points of interest raised along with several secondary points. The main points during the plenary discussion were:
- Performance Improvement Package (PIP) instead of major modification retrofits;
The financial community is not convinced that the market will be able to afford the cost and potential disruption of the major retrofit modifications.
On the other hand there are PIP retrofits available in the market for both aerodynamics and engines, normally initiated by an OEM or in collaboration with a specialist company. Individual companies have developed retrofit PIP modifications but they are very rare indeed (the level of approved data supplied by the OEM is not always evident).
- Intellectual Property (IP) rights and release by OEM’s;
There are some advocates of forcing the OEMs to release source data to recognized and approved retrofit organisations but there are so many pros and cons that they are not anywhere near the majority. There are also other parties that are willing to go it alone without the OEM source data and accept the financial consequences for the complete certification effort (specialist knowledge is a pre).
- By using the technology being developed by Airbus for the A350 to improve the cabin as part of a routine upgrade to the cabin, the possibilities of weight reduction are available to the owners/users.
Another section of the workshop added a word of caution by pointing out that the idea of only doing a retrofit modification for the weight reduction would not be financially viable if not combined with a planned regeneration and renewal.
During the discussion there were several proponents for cabin regeneration and renewal, one comment was very relevant “the cabin is upgraded as a rule every 5 to 7 years”. This generates an automatic retrofit window of opportunity for the owner/user of the aircraft.
- Lack of emphasis on cabin improvements, not only IFE-systems.
Attention was directed to include items relevant to cabin retrofits that are either less well-known or the result of more current needs or availabilities (for example, LED-lighting, safety, management, monitoring, environment - energy improvements) and are also very relevant for addressing maintaining ageing aircraft.

Other aspects of cabin design deserve to be considered one example being; the Lufthansa Star Alliance modular economy-class cabin seat concept for long-haul services, where members of the alliance may further customize the seat when implementing cabin retrofits (for example, choice of IFE, upholstery and the like features). Such innovations also have positive impact on wider-level on acquisition, maintenance, and spares costs and availability issues.

Wireless internet technology (for example, in the IFE context) is available but there is no common network available in Europe (due to lack of political agreement by EU countries) as opposed to the GoGo network in USA.

Furthermore, the potential replacement of conventional cabling (used either for communication and/or power) to achieve reductions in weight, power requirements and maintainability, as well as to increase levels of functionalities could be considered.

The secondary points of discussion were:
- Certification costs in time, money, location and safety restrictions:
All certification efforts are based on the safety assessment and the hazard assessment during the design of the system or unit. Retrofit organisations in general have no access to flying prototype platforms/airframes that have a special status from EASA/FAA.
- The nature of new concepts often result in properties or functionalities that are evident on the ground but cannot always be replicated in the air or have integration issues to be solved. It was proposed to use virtual/simulator certification if the cost can be acceptable.
9 Conclusion and future work
9.1 The RETROFIT project has concluded a number of activities:
- It consulted operators and the industry to understand the basics of retrofits
- It has identified technologies that are candidate technologies for retrofits
- It has looked into the rationale for previous retrofits
- It has identified research topics that could be beneficial for retrofitting
- It has looked at funding opportunities for the implementation of retrofits
- It has investigated the benefit/cost of retrofits, both in terms of commercial benefits and societal benefits

9.2 The RETROFIT project recommends:
- To stimulate the air transport sector and the research community to look for retrofit opportunities in view of the extended use of aircraft in the European theatre.
- To stimulate the sector to come forward with new retrofit proposals in the future.
- To stimulate PIP initiatives.
10 Recommendations to the European Commission
Pre-amble
• This section presents recommendations to the European Commission with respect to RTD for retrofit to be used for the Work Programmes of the Framework Programme FP7 as well as for the Horizon 2020 – the Framework Programme for Research and Innovation
Considering
• Aircraft have a long life to serve. Consequentially the global commercial air transport fleet consists for a large part of aircraft flying with technologies of the past. To obtain the maximum societal benefits from new technologies for aircraft, retrofitting needs to be encouraged. The European industry should take a competitive role in the retrofit market.
• In current European RTD projects on new aircraft technologies the potential application for retrofits gets hardly any attention. The global society is therefore missing benefits from new technologies, whereas the potential retrofit market is hardly explored by European companies.
The following is recommended
• It is recommended to require any RTD proposal for technology development for new aircraft to address the potential for retrofit. In promising cases for retrofit the RTD proposal should in addition dedicate a work package to this topic.
• It is recommended to take specific action to decrease the certification cost and time of retrofits. The high certification cost due to the currently needed repetition of costly tests is preventing the economic application of many new technologies. On the other hand, the recent progress in virtual (that is, software model based) testing reveals a potential to reduce the certification cost of retrofits. It is therefore recommended to stimulate the research on virtual testing and to encourage virtual certification.
• It is recommended to stimulate the research and development on the specific retrofit topics.
- To incorporate research topics for retrofits in the next call of the RTD Framework program, through feasibility studies ( level 0), maturing promising technologies through Level 1 projects and integrate retrofit technologies in Level 2 projects.
- To demonstrate retrofit technologies in Clean Sky and SESAR.
- To stimulate and facilitate the implementation of retrofits that also benefit societal issues like environmental protection, reduce oil dependency, increase safety and security and ensure mobility by the use of TEN T, structure and regional funds

Potential Impact:
please refer to previous paragraph.

List of Websites:
www.fokkerservices.com/RETROFIT_FP7
final1-265867-1150877-retrofit-d6-3-publishable-final-summary-report-fs-v2-1.pdf