An exchange on artemis-list@asi.org November 22, 2000
published in MMM #141 December 2000
Reprinted MMM #303 July 2019

Greg Bennett
We did not reuse the Apollo capsules, or any part of them. But, could we have?

I was just wondering if there were anything inherent in the design of the Apollo capsule that precluded reusing it. It was a tiny part of the spacecraft, but it did contain a lot of expensive equipment.

I often wonder whether flying a whole new spacecraft is really more safe than using one that has been proven in flight. Perhaps the fact that each capsule went through extensive testing made up for lack of operational experience with the spacecraft, Apollo 13 notwithstanding.

Wallace McClure
The short answer is yes to part of them, or at least some of them could have been refurbished to fly again. I also assume you are using a new Service Module with them. In particular, those used for Earth orbital missions could probably have been reused for Earth orbital missions.
• Structure — Could have been reused, but you would have to inspect to ensure no sea water intrusion or corrosion (e.g. don’t get salt water in the structure, particularly inside the pressure vessel.)
• Thermal Protection System — This was sized for a direct return reentry from the Moon. Run the numbers and you see the heat load from an Earth orbital reentry was less than 50% of that of a lunar return. The heat shield was not replaceable in sections, but you could have theoretically remachined down the uneven remaining unablated honeycomb and reused it for an Earth orbital mission. (With inspections, of course!) Theoretically, you could replace the entire ablative reentry shield. But that was never considered.
• Avionics — Reusable, yes, with replacement and testing of batteries, etc.
• ECLSS — Most of the ECLSS was in the service module. You would have to renew the ECLSS LiOH [lithium hydroxide] and it was reusable. You would have to replace the connections to the service module.
• ACS — The CM ACS was really only used post SM separation (and primarily for roll control). At a minimum, you would have to clean and replace all the burst disks, etc. But from a first look, you could probably reuse the tanks, valves, engines etc.
• Parachutes, etc. — Definitely replace them. They were rampacked and certified for only one use. Also the pyros, etc. would need to be replaced.
• Soft Goods — Inspect and replace seals, rubber gaskets, etc. You do need to look at them.
• Of course, if any vehicle was used outside of the expected operational conditions, reuse might not be possible — land landing, hot-hot reentry, sea water sloshing around inside for weeks, etc. But for a run-of-the-mill Earth orbital mission — probably most of it could have been refurbished and reused.

Dale Gray
As I understand, the capsules evolved over time even after Apollo 8. Reusing an old capsule would be to take a step backward in safety, performance, mass. The returned capsules were far more valuable as national treasures, complete and untouched than any conceived salvage part or in whole.

Andrew Newstead
I believe the Apollo 14 docking probe was reused with one of the Skylab Apollos or the ASTP Apollo. Because of the difficulties with it during the flight of Apollo 14, it was brought back for engineering analysis, which found nothing wrong with it and it was reused as an economy measure. It gave trouble again when reflown, so go figure!

Ben Huset
To date, all the Soyuz capsules have been used only once.