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Comment by maccam94 | Hacker News Reader

It only needs one or two of its three engines to land.

I think the flip maneuver is a big issue as it happens near ground and if it fails there is not time to recover irregardless if there are other engines that could perform it.

The flip starts with 3 engines and should work even if 1 of them doesn't start.

It still failed on SN9.

they weren't trying to light all 3 for SN9.

now they light all 3 and turn 2 off when one lights.

So a single failure of a prototype means its never ever ever gone work? What kind of logic is that?

Also you are wrong. SN9 actually used 2 engines for the flip, not 3.

They only swapped to 3 for SN10 and the flipped worked perfectly there. The problem with SN10 was the temporary helium system they put after SN8 in so the engine was ingesting helium.

The point is that you have engine out capability both on the flip and during landing. Of course over time SpaceX need to test some of these profiles in more detail, just as they did for Falcon 9 where they tried various ways of landing.

Of course not. But you can't assume that anything will work 100% of the time. So what will be done if in a rare case the flip maneuver fails? Engines fail but a plane can still land with just one engine. If we are going to be doing intercontinental flights it needs to be as safe as flying.

What happens to a plane if the tail falls off?

What happens if all the engines fail?

What happens if it flies into a mountain?

The Wright Model A crashed, and actually killed someone. That's why aircraft are so unsafe.

They can do the flip at a higher altitude to provide more time for recovery.

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