5 - 38 LM ECS BUDGET GROUND RULES AND ASSUMPTIONS 1. Cabin O2 leakage rate was 0.2 lb/hr while pressurized 2. Metabolic rates were varied according to Volume 2 of the Spacecraft Operational Data Book 3. Metabolic O2 consumed was (1.643 x 10-4 ) x (metabolic rate) 4. LM pressurization requires 6.62 lb of O2 5. Cabin pressure regulator check requires 2.65 lb of O2 6. H2O consumed because of sublimator cooling was total heat removed divided by 1040 (btu per lb) of H2O 7. H2O lost due to urination was 0.11 lb/hr per man 8. Cabin temperature control was set to 72° F 9. Average glycol fl ow rate was 250 lb/hr 10. Budget was performed on the operational trajectory and may change when the revision 1 is analyzed. TABLE 5-13 LM ECS Summary (a) Descent Stage Description O2, lb H2O, lb Loaded 48.00 210.6 Unusable 3.40 16.4 Available for mission 44.60 194.2 Required for mission 26.17 142.4 Usable remaining in tanks 18.43 51.8 (b) Ascent Stage Loaded 4.86 85.00 Unusable .74 4.20 Available for mission 4.12 80.80 Required for mission 1.95 45.48 Usable remaining in tanks 2.17 35.32