F9 engine out at launch.

[speedevil]

In the recent interview, Gwynne Shotwell said:

Block 5 Merlin 190k lbf thrust, have tested current Merlin to around 240.

Does this imply ability to do engine out, even just after it's cleared the tower?

Neglecting a pile of stuff.
190*9 ~=240*7.

This means that in principle, F9 could perform a completely nominal mission, with an engine out immediately as it clears the tower, even if it needed to shut down the opposite engine completely. (assuming no other damage).

As it does not need to shut down the opposite engine completely, but can take the opposite couple of engines to ~85% thrust, and the rest to ~118, with modest gimballing, it would seem there is moderate margin there.

Even if we accept (as seems reasonable) 240 is not reliable, if 230 is 'will not explode and will work for one flight 90% of the time', you can also modestly crank the thrust to the point you expect an engine loss 1% of the time, and get >3 nines reliability as you can cope with an engine out.

This of course assumes that there is a predictable and known relationship between thrust profile and likelyhood of engine failure, and that engine failure is benign, and that this design methodology is acceptable by the customer.

(I am aware of CRS1 - but this was 0:37, after a quarter of the fuel had been burned).

[Lars-J]

All F9 engines gimbal. There is no need to shut down the opposite engine if a failure occurred. So why the talk of taking the opposite engine to 85%??