Conceptual Design of a Reusable TSTO: Guess Data estimation and Matching Analysis

Nowadays space access is guaranteed by expandable launchers which, once the mission has ended, can’t be reuse for the successive mission. This involves a big waste of resources and necessarily high costs. One solution to reduce the costs and gain flexibility in space missions is the use of reusable or partially reusable vehicle. Reusable launch vehicles are facing a great evolution in the last years, and in particular reusable two-stage-to-orbit have been identified from many studies as the vehicle of the future in the aerospace field because they have the capability of delivering a wide range of payload in orbit at low cost, with a greater flexibility using conventional airports and infrastructures even gaining many operative and legal advantages. This thesis has a twofold target: the first is to find a useful method to define the most important data, called guess data, which are used to start the conceptual design of a TSTO vehicle and the second is to adapt the matching chart analysis to this type of vehicles; for both the points it has been developed a Graphical User Interface in Matlab environment using App Designer. In chapter 1 the concept of the two-stage-to-orbit and its historical evolution will be introduced, the most important state of art typologies of staging and a brief explanation of the types of engine. In chapter 2 statistical analysis will be developed, a database of vehicle will be created on the basis of the type of propulsion of the first and the second stage, and then a methodology generated for the calculation of guess data is presented, at the end of the chapter the GUI is shown with an example of its use. In chapter 3 the method to execute the matching chart analysis is explained and all the requirements that both the first stage and the second stage must fulfil are introduced, in particular, for the first stage will be analysed the take-off req., second segment req., climb req., cruise req. and landing req.; on the other hand, for the second stage the requirements analysed will be the orbit-achievement req., the re-entry req., the payload req., and lastly the landing req. Finally, in chapter 4 a method for the weight estimation will be submitted and a Graphical User Interface to calculate the matching charts is shown to the reader with an example of its use.