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Landing a first stage rocket (F9R) in the ocean has been stated that it is corrosive and will damage rocket components, thus making rapid reusability impossible or too expensive to repair each component. The other goals are to land on a barge or return to a launch pad on land. While we're still waiting for success, what is the affect of fresh water on a rocket? Would dropping a first stage rocket in a fresh water lake allow for rapid reusability? I don't know what the affect of fresh water, perch, walleye, and catfish is on a first stage rocket, but I imagine it is less than a fireball after smacking a barge or salty ocean water.

One site I had in mind would be the Great Lakes, specifically, Lake Erie. In Cleveland it has rail connecting the docks at the Lake to a NASA flight center and international airport (8km from lake).

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  • $\begingroup$ Related: Could Falcon 9 splash down IN water? $\endgroup$ – kim holder Apr 27 '15 at 15:16
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    $\begingroup$ "While we're still waiting for success, what if we consider a completely new and different approach that's going to have its own problems that we haven't been thinking about and designing for for the last five years?" $\endgroup$ – Russell Borogove Apr 27 '15 at 15:29
  • $\begingroup$ It isn't impossible to recover high value rocket propulsion and avionics components in sea water. You just have to work at the engineering of protecting the vehicle during the landing and design the entire system around it. (Then of course, you have to sell it :) ) Boeing's design (with significant testing) for recovering a three SSME pod, from the 1990s: forum.nasaspaceflight.com/index.php?topic=19388.0 $\endgroup$ – Matt Jessick Dec 16 '15 at 13:02
  • $\begingroup$ The problem with "Rapidly reusable" is the time of inspection. Theoretically for (truly) reusable vehicles all you need is to refuel them and launch again. Practically first they are meticulously checked for any damages, then none are fully reusable and need some maintenance, and only then you can refuel them and prepare for launch. $\endgroup$ – SF. Dec 16 '15 at 13:23
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Lake Superior is much much bigger, colder, and less populated on its rim.

However, the core issue with the F9R landing in the ocean has been survival of the impact in the water.

Unlike an SRB, the Falcon 9 first stage is not very strong. The SRB being a solid, requires that the entire case take the pressure of the burning engine. (To terminate an SRB, you pop the top off with explosives, or unzip it down the length so that there is no net thrust). But the SRB's are very strong, and STILL they would get bent out of shape on landing in the water.

The Falcon 9 first stage while not pressure stabilized like an original Atlas first stage (which could not support its own weight, unpressurized) it does rely on some pressurization for support during launch.

But not strong enough to hit the water and survive, as the attempts to land in the ocean without an ASDS barge to land on demonstrated. It can get to zero height, zero velocity, but the topple over into the water destroys it.

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    $\begingroup$ For missions where the chutes worked properly, I'm not aware of SRB structural problems due to splashdown. $\endgroup$ – Organic Marble Apr 27 '15 at 16:09
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    $\begingroup$ Google solid rocket booster "out of round" (and optionally throw Feynman in there). When the SRBs fell over, they'd get very slightly flattened as they impacted the surface. The way the refurbishment process measured and corrected the out-of-round condition was inadequate, and that may have contributed to the Challenger disaster. $\endgroup$ – Russell Borogove Apr 27 '15 at 16:16
  • $\begingroup$ The booster from the Ares I-X flight buckled upon impact. $\endgroup$ – Tristan Dec 16 '15 at 18:10

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