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Comment by wazokazi | Hacker News Reader

Was there ever any consideration given to building a "testing harness" to physically simulate the F35 landing? Something like the "dead load" testing that the EMALS undergoes. Just in reverse. Anyway, that was great read.

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There was a lot of static load testing done, and things like a drop test [0] of a full scale article. But to my knowledge, the only way to test the dynamics of a carrier arrestment is to actually do an arrestment. We do them on land; NAS Patuxent River and NAS Lakehurst (among others) have a full set of Mark 7 arresting gear like you would find on a Nimitz class. Lakehurst also has the advanced arresting gear present on the Ford class.

[0] https://www.youtube.com/watch?v=lGPseVNfZO0

How much of a difference is there between dry land arresting and carrier arresting? I would guess some since the carrier represents a somewhat dynamic surface, and flight conditions might likewise vary. Is there enough that a second round of carrier based testing is required that might trigger significant changes?

All of this was done as a work up to a carrier deployment. In software terms, trying the arrestments on land is deploying to test, doing them on a carrier is production. There were three separate developmental test deployments to carriers for the F-35C. Each deployment sought to expand the understood envelope and and handling procedures. The hook redesign happened before the first deployment. The hard landing story in the post happened during the work up to the third and final deployment.

Had the hard landing occurred on a carrier, how would the gentle, flared landing be accomplished? Try to reach an airport on land, ditch the plane in the water, maybe catch the plane with the net on the deck? Our just do a normal carrier landing and hope for the best?

The Navy developmental test community does carrier suitability testing of every new airframe, and there's a whole program of nominal and off-nominal arrestments they have to test in order to prove the jet can recover in all expected scenarios.

I don’t know if it’s significant but on the carrier the arresting system is going 25-30 mph. The ship is moving.

Again, maybe not enough to really matter, but enough to at least take into consideration.

I imagine it means that the arresting system is being tested to greater limits on the ground than at sea, all else being equalish?

Since the relative speed of the aircraft to the ship will be reduced.

That is all correct. I have flown gliders and studied physics :)

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