LS2022 23 Call3

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First name Last name Personal ID number Score Launch systems (8 credits) June 20th, 2023 First part - Closed book Each question is worth 1 point. The student must obtain at least 6 points (without rounding) otherwise the second part of the exam will not be corrected. WRITE THE ANSWERS IN THIS SHEET Scenario – Airborne space launcher A winged space launcher is launched from a subsonic aircraft at 20000 m altitude with zero-flight- path angle. • Payload 500 kg @ 220 km altitude • Number of stages: 2 (Kerosene / Oxygen) 1. Coffee-time discussion with one of your colleagues Do you agree? Mark them as true (T) or false (F) (correct answer +2, wrong answer -1, no answer 0) I launch from higher altitude so gravity losses are lower than drag ones Ignition delay from the instant of detachment is a performance requirement (not a programmatic one) The missile is launched from the thermosphere to ease orbit insertion Recovery of even the first stage is impractical due to high-altitude launch Given the payload reported above, the launch platform can be a small aircraft with max payload of about 1500 kg. 2. What are the requirements that are applicable to this kind of launcher? (Three valid answers. The selection of a wrong answer invalidates the question.) T/W may be lower than 1 Use of green propellant Storability Specific impulse of the propulsion unit is less than 300 s Guidance via infrared homing Ramjet propulsion Launch Systems Page 1 3. Consider the detachment from the launch platform. The system will have a free-fall trajectory before ignition to ensure safety of the aircraft. You want it to be stable. Briefly discuss the options you can implement. Remember the presence of the launch platform. 4. What if we change the propulsion system and we move to solid rocket motor?…