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6

Yes and No. The altitude data presented on the altitude indicator (tapemeter) depends on the mode select switch setting. MODEL SEL switch LGD RADAR: Radar altitude, altitude rate... are displayed. PGNS: LGC-computed altitude, altitude rate... are displayed. AGS: AGS-computed altitude, altitude rate... are displayed. Source: LM Apollo ...


1

No. The "LM altitude" computed from the Landing Radar slant range is only corrected for the altimeter beam angles, not the vehicle attitude angles. The altimeter beam angles are used by the LGC in the computation of LM altitude from LR slant range output. Source: LMA790-3 -LM APOLLO OPERATIONS HANDBOOK pp. 2.2-25 and 2.2-26 On Figure 2.2-9 you can ...


9

The J-2 was, to use a technical term "kind of throttleable". The engine incorporated a Propellant Utilization (PU) valve that could change the mixture ratio and thrust during operations. Picture from the J-2 Fact Sheet (really a whole, fabulous book). During engine operations propellant sensing devices in the vehicle propellant tanks control the ...


7

A single axis rotation (SAR) was performed from the initial to final attitude, unless they were avoiding gimbal lock, in which case it was split into two rotations. It has been shown in MIT/IL Report E-1832 that it is convenient to perform attitude maneuvers by simultaneous maneuvers in three axes. However, under certain ...


5

The order in which rotations are applied matters. 260 roll around REFSMMAT x followed by 90 pitch around REFSMMAT y is the same orientation as 90 pitch around REFSMMAT y followed by 260 yaw around REFSMMAT z.


6

Frank O'Brien in his book "The Apollo Guidance Computer: Architecture and Operation", on p. 229 concludes that effect from sublimator vapour thrusting could've been measurable: A quite real source [of unaccounted in state vector translation] arises with the exhaust from the LM sublimator, used to cool the vehicle's electronics. Although producing the ...


21

What happened to the old canisters after they were used up? Were they manually replaced? Were they tossed behind the seats? @OrganicMarble's answer covers this with reliable sources quoted. I only wish to add (after going through Apollo-7 to Apollo-11 flight journals), the exact mentioned in communication compartment numbers with (square type Command ...


19

The canisters were manually replaced. Here is the appropriate checklist section. From CSM Operations Checklist Section 10 Systems Management Used canisters were stowed in the container that the unused canister was removed from. The CO2-odor absorber filter change sequence involves numerically identified filters and alphabetically identified filter ...


7

The National Archives website has the stock footage for the NASA documentary "This is Mission Control". In the footage they show closeup shots of several screen in the MOCR and the staff support rooms. The footage is from October 1970, so it's probably safe to assume the screens show data for an Apollo 14 simulation run. Here are two examples from it. Lunar ...


6

These are the best I've seen. They are from the recent restoration of the Apollo MOCR but are accurate AFAIK. Source: https://wordpress.accuweather.com/wp-content/uploads/2019/07/mission-control-7.jpg


2

1) In June 2007 there was a major computer failure on International Space Station, which left the station without thrusters, oxygen generation, carbon dioxide scrubber, and other environmental control systems, causing the temperature on the station to rise. The root cause of the failure was found to be [the] condensation inside the electrical ...


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