Draft Claim: The author has indicated this claim is in a draft state and not yet ready for review.
Claim
The Exit Airlock Mechanism Can Be Engineered to Work Reliably
Evidence
To exit the tube, the vehicle will pass through an already open fast-acting door first, and that door will start closing immediately. The other end of the airlock is covered with a burst disk. The ambient air pressure at the airlock’s altitude (15km) is around 12000 Pa and the pressure inside the tube is 5 Pa. When the vehicle breaks through the burst disk, the rarified outside air will start travelling into the tube at the speed of sound. The fast-acting door needs to finish closing before the ambient air rushing into the tube reaches it. The math in the model estimates that to meet these requirements the airlock needs to be at least 288 m long if the fast-acting door is engineered to close in 1 second. The fast-acting door can be backed by a second slower door that is designed to achieve a better vacuum seal.
Reviews
The following reviews are limited in scope to the validity of the claim made above, and do not imply that the reviewer has taken a position regarding any other claim or the overall feasibility of a concept that is supported by this claim.
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Reputation: 0Verdict: SupportsBachelor’s Degree in Mechanical Engineering with an Aerospace Track from the Colorado School of Mines (CSM). Co-authored an academic publication (doi: 10.2514/6.2024-4884) as an undergraduate researcher in CSM’s Space Resources Department as part of NASA’s 2023 BIG Idea Challenge. Co-founder and Chief Operations Officer of Unleashed Robotics, Inc. – a robotics startup developing novel robotic mining technologies with space resource applications. Incoming SpaceX Propulsion Engineer.“Double-checked the calculations made in this claim”
I read the claim and discussed it with Phil. I wanted to double check the 288-meter tube length figure asserted here. Assuming that the external air flows into the tube at the speed of sound at 15km (~295 m/s) immediately after the burst disk is ruptured, it will reach the fast-acting door in 0.976 seconds. For a vehicle traveling at Mach 40, if the fast-acting door starts closing immediately after the vehicle passes it, 1.0003 seconds will pass before the external air reaches the door. Thus, the fast-acting door will be capable of sealing the airlock before external air can reach it.
Submitted: