Phenomena in the highest layers of the atmosphere play an important role in day-to-day life. They have a large influence in large-scale, long-term weather effects and climate, but also on satellite navigation and communication and re-entry or satellite orbit decay: issues of growing importance in modern society. Nonetheless, data from the middle- and upper atmosphere (50 – 120 km altitude) is scarcely available, because the means are currently not available to deploy a sensing system in this region in a cost-effectively manner. Atmospheric balloons have a maximum altitude of approximately 40 km, whereas satellites cannot orbit lower than 200 km. Remote sensing techniques can be used in some cases, but this does not work for all parameters, and discrimination in altitude proves difficult with these methods. Because of this knowledge gap, the region is therefore sometimes called the “ignorosphere”.
The only available way to perform in-situ observations in these layers is by means of so-called sounding rockets: rockets that are launched almost vertically to a certain altitude and then fall back through the atmosphere. These rocket systems are expensive both in product cost and operational cost. This limits their practical use to few yearly launch campaigns, with one or two launches each, and for this reason they provide scarce data from single-point measurements, and not the continuous datasets, or datasets over larger areas that are necessary to improve and validate atmosphere models.
As a solution to this problem, T-Minus Engineering is developing the T-Minus DART: a small and cost-effective rocket system for fast and easy access to space and the highest layers of the atmosphere. By making full use of the trend of miniaturizing electronics, applying a smart and fully integrated design, and using state-of-the-art materials and manufacturing techniques, estimates show that the product- and operational cost can be reduced by a factor 10 with respect to other rocket systems.
The T-Minus DART can reach an altitude in excess of 120 km, as verified by validated trajectory simulation software. It is designed to accommodate a variety of miniaturized payloads: from highly integrated, electronic multi-sensor packages to simple chaff or chemical tracers. The payload diameter is limited at 30 mm, but sufficient for plenty of sensor systems due to the current trend of miniaturizing electronics and sensors.
In this project, T-Minus Engineering answers all questions regarding technical, economical, legal and operational feasibility of the DART product. The steps needed to bring the production process to the required Technology Readiness Level (TRL) are identified to assess the technical feasibility. The main focus in this respect is on the development of key enabling technologies: the propulsion module (the rocket motor) and the electronic flight computer. Conclusions on economic feasibility follows from a detailed market survey, resulting in a target sales price, and an analysis of the production cost. Acceptance in the conservative sounding rocket market is very much driven by product reliability and safety. For this reason, conducting a product qualification test campaign in a representative operational scenario is essential. During the SME-instrument project, it is attempted to formalise a consortium with which such a test campaign will be carried out. Finally, the production and operation of a rocket system shall conform with specific legal requirements. An in-depth study thereof is carried out during this project as well.
