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by rdtsc 20 days ago
Some are on a gimbal and they specifically talked how others gimbaled out a bit to compensate. This is specifically something they designed in and not an accidental lucky save. In this flight they didn’t intend to test “one engine out” feature but it worked out that way.
1 comments
SilverElfin 20 days ago
See my other comment. The vacuum engines are NOT on a gimbal. None of them. The sea level engines on starship and several of the engines on the booster are on a gimbal. But not the vacuum engines for space.

EDIT: I cannot reply further in this thread, but my understanding is that the non vacuum engines are not intended to stay lit throughout the orbital flight in a typical mission. If they are, they can gimbal and compensate.

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rdtsc 20 days ago
> The vacuum engines are NOT on a gimbal. None of them

I said some raptor engines are on a gimbal, not vacuum engines.

To be precise, the three central engines can gimbal up to 15 degrees. That can control the thrust vectoring when an engine fails, and that’s what happens in the last flight.

Since the flight already happened and we know it didn’t spin out of control (unless you imply their diagnostic and telemetry was completely off and the engine was actually on) something must have compensated for the failure. It wasn’t magic, it was in fact the central 3 engines that did that.

You may be confused because those are called sea level engines, but that doesn’t mean they can’t work in vacuum.

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adgjlsfhk1 20 days ago
I think previous comment means "on a gimbal" as in "angled at a non completely prograde direction" (presumably angled such that each engine points through center of mass so that none of the engines impart a torque)
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labcomputer 20 days ago
The person you’re replying to is trying to play rhetorical word games.

The upper stage has six engines. The outer three engines are “vacuum engines” (optimized for operation in space). The inner three engines are “non vacuum engines” (optimized for operation in the atmosphere, at sea level).

The outer three vacuum engines are not gimbaled, but the inner three sea level engines are. Thus, it is completely accurate to say that they gimbaled some of the engines to compensate for the engine failure.

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