With the upcoming attempts to simulate a landing over water with the Falcon IX first stage comes a possible opportunity to expedite actual re-usability. It just might be possible to grab a stage that has reached zero velocity over the water with a helicopter and return it to a barge or dry land for inspection and possible early reuse.
My understanding is that over the next several Falcon IX flights SpaceX is going to try to reenter the first stage and bring it to at least a momentary hover above the Atlantic before the stage goes swimming. Saltwater immersion is unlikely to result in a re-flyable stage even if it enters the water at near zero velocity. The recently fired hot nozzle will probably object among other things less dramatic.
Landing on a barge has been suggested several times and is even the target of a patent attempt by Blue Origin. In this early case, a barge may not be the best choice. The barge would either have to be exactly where the stage reaches the surface or the stage would need enough propellant to ensure reaching a possibly out of position vessel. The landing gear would have to be fully developed for the first landing (barging?) attempt, which is a mass and complexity issue. The tall and skinny visuals of the Grasshopper would concern me for a barge landing in anything other than a perfect sea state.
Starting with attempt one at reaching near zero velocity water relative with a Falcon IX, it might just be possible to rendezvous with a helicopter before the stage goes swimming. The factor of ten or so speed difference between a chopper and a barge might make the difference between possible and not for the vehicle meeting at the precise time of hover. The first rendezvous attempt might be no more than a tag-you’re-it with a fast maneuverable bird with a light line with fail-safe breaking strength. A momentary hook up with controlled line tension before the connection is released or breaks. It may not be possible to perform the rendezvous in this manner which would make a full blown recovery attempt questionable until a few answers are obtained.
Even before attempting a full stage rendezvous, it would make sense to try this with either the Grasshopper or a vehicle supplied by others like Armadillo or Masten. An over land demonstration with known vehicles would seem to be a low risk method of training pilots, rocket controls, and developing effective rendezvous techniques. The first trip several hundred miles off shore with few witnesses should not be the first try at a recovery.
If all the preliminaries point to a useful possibility of recovery, then it might make sense to go get a real one. I have no idea of the possible attach points on a Falcon IX first stage in simulated landing configuration. There might be something in the inter stage area that would be just fine for a simple hook from the chopper to snag, or there may not. If there is not, it might make sense to hang a cargo net under the chopper and simply net the stage. It seems possible that loads could be distributed in such a way as to eliminate damaging stresses on the stage so that it could be reused without rebuilding.
The hooked or netted stage could be gently lowered into a soft cradle specifically designed for the stage on a barge or land within range of the helicopter. With air refueling it might be possible to return to launch site for fast turnaround after some experience is gained.
It might just be possible to reuse the Falcon IX first stage earlier than commonly expected without even the mass and cost of landing gear. This would certainly be performance enhancing compared to a full return to launch site vehicle requirement.
These ideas are not all mine or all new. I just thought that it was a good time to mention them again.
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