Transcript Lessons-Apollo

Lessons from Apollo*
•Data from NASA Apollo 11 Press Kit
•Shows spacecraft weight delivered to LEO
(Low Earth Orbit)
•Shows weights for each portion of Apollo 11
•Command & Service Module
•L.E.M. (Descent and Ascent stages)
•Various sub-systems (water, ECS package,
etc.)
•Propellant weights for each stage, engine specs
•Allows calculation of “Parametric” values
Lessons from Apollo*
Lessons from Apollo*
Lessons from Apollo*
Lessons from Apollo*
Trans Lunar Injection Summary
•Total vehicle weight in LEO
= 296,379 pounds
•Total propellant weight
= 157,010 pounds
•Stage 3 engine - one J-2 using Lox/LH2
•Command/Service Module weight = 67,164 pounds
•Lunar Excursion Module weight
= 33,205 pounds
•Total Weight delivered to Low Lunar Orbit
= 100,369 pounds
•Lunar Orbit Weight Fraction = .33
•So, for every 10,000 lbs in LEO, Saturn put 3300 lbs in LLO
(using LOX/LH2 J-2 class engines)
Lessons from Apollo*
Trans Lunar Injection Summary
•For every 10,000 lbs in LEO, we can put 3300 lbs in LLO
•Requires LOX/LH2 J-2 class engines
•Limited amount of time from launch to TLI burn
•Not generally used for shuttle-based upper stages
•Good for un-manned launches, like Delta’s II thru IV
•Other propellants (MMH/NTO4), deliver lower performance
•Isp LH2 = 450
Isp MMH = 338
•MMH/NTO4 can be stored for longer periods
•Used for CSM & LEM engines
•For MMH engines, 10,000 lbs LEO puts 1125 lbs in LLO
Lessons from Apollo*
Current Launchers Improvements
•Delta II (7925H-10L) can place 10,120 lbs in LEO
•Current MB-60 engine is higher performance than J-2
•Isp = 467 versus Isp = 420 for J-2
•Required propellant = 10,120*.666*(420/467) = 6019 lbs
•Payload to LLO = 10,120-6019 = 4101 lbs (extra 761#)
•Good for launching cargo, supplies, etc.
•Delta IV (5,4) can place 25,300 lbs in LEO
•Propellant = 15,048 lbs
•Payload to TLI = 10,252 lbs
Lessons from Apollo*
Lunar Orbit Insertion
•Apollo Summary
•Command Service Module/LEM weight at TLI = 100,369
•LOI Propellant used = 12,011 lbs MMH/NTO
•Apollo Isp = 318 versus Isp = 338 for RS-72
•Fuel fraction = .112 ……. Payload fraction = .887
•Delta II (TLI = 4101 lbs) payload to LLO = 3,639 lbs
•Delta IV (5,4) (TLI = 10,252) payload to LLO = 9,099 lbs
Lessons from Apollo*
Lunar LANDING
•Apollo Summary
•LEM weight 33,205 (Apollo 11)
•Descent Propellant used = 18,100 lbs MMH/NTO
•Payload to Lunar Surface = 14,501 lbs ….
•Apollo Isp = 318 versus Isp = 338 for RS-72
•Apply to LEM weights, current fractions are …
•Fuel fraction = .513 ……. Payload fraction = .487
•Delta II (LLO = 3639 lbs) payload to Lunar Surface = 1,772 lbs
•Delta IV (5,4) (LLO = 9,099) payload to LLO = 4431 lbs !!!!