New answers tagged apollo-program
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For lunar flights, the Apollo command and service module did not require retrorockets to return the command module to Earth, as the flight path took the module through the atmosphere, using atmospheric drag to reduce velocity.
Retrorockets were used to back the S-IC and S-II stages off from the rest of the vehicle after their respective shutdowns during the ...
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No it didn't, Apollo was designed with a parachute assisted water landing in mind. However there was one contingency for which considerations for a hard landing (landing on the ground with parachutes instead of the water) were made.
During the launch the Apollo spacecraft went through several stages and during each one there was an abort plan. For the most ...
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No, the Apollo Command Module (the part that made it back to Earth) did not have braking rockets. Instead, it had several parachutes and landed in the water.
The descent was first slowed by two drogue chutes. These deployed at about 7 km above sea level and slowed the spacecraft down enough so the three main chutes could be deployed at about 3 km. These ...
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Absolutely not
Origins of NASA Names, SP-4402, is the 242-page official NASA history of the names of launch vehicles, spacecraft, manned spaceflight programs, sounding rockets, and NASA field installations. The entry for Apollo is three pages long and makes no mention of it being an acronym. Notably:
Abe Silverstein, Director of Space Flight Development, ...
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Why wasn't the Apollo spacecraft made so that the astronauts would simply lie on the bottom of the capsule during launch and reentry, without their legs up? They would just need to be tied to the bottom somehow (to a mattress perhaps).
Actually, it sort of was, later.
While the standard and ideal configuration had three seats suspended from shock absorbing ...
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The water impact deceleration was short but it could be strong. Vertical speed with only two parachutes was 36 foot/sec or 11 m/s, horizontal wind speed during a storm could be more. Apollo 8 wind speed was 32 ft/s or 19 knots or 9.75 m/s.
There were attenuator struts to reduce the landing shock. When the capsule hit the water, the attenuators extended and ...
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For more details on how the Apollo guidance computer was designed and built, and the people who did it, take a look at We Hack the Moon, the 50th anniversary website of the MIT lab that led the work. During the open to the public museum display in their lobby from June to October of 2019, they had a mockup of the LEM that let you try to land it yourself, ...
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It's all hard.
Try operating a basic ascent to orbit simulator where YOU control eg just the thrust. See how many attempts it takes you to reach orbit.
Decades ago I did this many, many .... times. Even with vast experience, achieving orbit was a pleasant surprise.
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Chariots for Apollo NASA SP-4205 (1979) By Courtney G. Brooks, James M. Grimwood and Loyd S. Swenson, Jr. (web version) (pdf version)
Moonport NASA SP-4204 (1978) By Charles D. Benson and William Barnaby Faherty (web version) (pdf version)
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Interesting that some simple astrodynamical problems indeed can be solved without a computer, just by pen and using high-school algebra.
For example mass of payload a rocket launches can be calculated by Rocket equation. The caveat is we don't account for 1)atmosphere drag and 2)non-straight trajectory of rocket.
Also orbit transfer can be calculated easily, ...
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As just one example consider the Lunar landing. If you think about a vehicle sitting on top of a rocket, with the thrust vector of the rocket passing through the centre of mass of the system for a moment you'll realise that it's not stable: there's nothing making it want to point in any particular direction. But you need it to face in some very particular ...
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Your spacecraft would need to be several orders of magnitude larger than the Saturn-Apollo.
No human pilot has successfully performed a rendezvous without a computer. Note that rendezvous is bringing two spacecraft close together in orbit, position, and velocity. Docking is the actual physical contact between two spacecraft. The latter can and often is ...
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According to this article, the nave & guidance computer had 36K of ROM, and 2K of RAM.
https://history.nasa.gov/afj/compessay.html
It lists 30 different “programs” that it could run.
The programs probably measure things like temperature, pressure, gyroscopes, etc. as input. The software then decides how to do motor control to keep the vehicle stabilized ...
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“Do I have a very naive concept of space travel?“ - honestly, yes you do. Here is an excerpt from Don Eyles’s wonderful book Sunburst and Luminary: An Apollo Memoir:
Guidance would be processed every two seconds, repeatedly correcting and refining the trajectory based on new data from navigation. Into the guidance equation, with each turn of the crank, went ...
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Assuming this isn't a troll question and you are serious about wanting to know what computers are used for in spaceflight (prior to 1988), NASA has a great resource for you:
Computers in Spaceflight (PDF, 494 Mb)
From the introduction:
Computers are an integral part of all current spacecraft. Today
they are used for guidance and navigation functions such as ...
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I don't understand why a computer was needed at all, either on the ground or inside the space craft.
As Ben (PearsonArtPhoto) pointed out, computers have always been a part of launching rockets. By no means an optional one. Computers are needed to avoid collisions with the debris around earth, to auto-pilot spacecrafts and to monitor mission data (sensors, ...
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First of all, the ground team could have, and in fact did, do most of the orbital navigation remotely. This report mentions the fact that the on board computer was secondary for Apollo 8, with primary being systems from the ground. The spacecraft did have to do a few things, including making some realtime adjustments during the landing based on the actual ...
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