1. AAE450 Senior Spacecraft Design Poliskie - 1 T.J. Poliskie Week 5: February 15, 2007 Propulsion Earth Taxi, Mars Taxi Group Zero Boil-Off Cryogenic Propulsion

2. AAE450 Senior Spacecraft Design Poliskie - 2 Zero Boil-Off Cryogenic Storage Passive Storage –Boil-off occurs at a constant rate –0.36 kg/hr LOX –0.45kg/hr LH2 Zero Boil-Off –Active cooling using cryocooler/mixing unit –Power requirement depending on tank size and temperature (50-200W) –Additional equipment needed (radiator, heat exchanger, pump)

3. AAE450 Senior Spacecraft Design Poliskie - 3 Updated Storage Mass/Volume Earth Taxi – Payload: 17.5 mt – ZBO Storage Mass: ~500kg –Propellant Mass: 20.9 mt –LH2 Storage Volume: 68 m^3 –LOX Storage Volume: 24 m^3 Mars Taxi – Payload: 12 mt –ZBO Storage Mass: ~500kg –Propellant Mass: 29.5 mt –LH2 Storage Volume: 90 m^3 –LOX Storage Volume: 30 m^3

4. AAE450 Senior Spacecraft Design Poliskie - 4 Thrust Determination Earth Taxi –ΔV: 3.25 km/s –Burn Time: 200 s –Thrust: 461 kN Mars Taxi –ΔV: 5.02 km/s –Burn Time:250 s –Thrust: 520 kN Source: Poliskie, 2/14/07

5. AAE450 Senior Spacecraft Design Poliskie - 5 Backup Slides

6. AAE450 Senior Spacecraft Design Poliskie - 6 Propellant Mass Calculation

7. AAE450 Senior Spacecraft Design Poliskie - 7 Propellant Storage Volume mlh2 = m_p./(1+mixr) mlox = mixr.*mlh2 v_t_lh2 = mlh2/70.9*1000 v_t_lox = mlox/1149*1000 Note: 50% propellant storage volume added to accommodate zero boil-off