Merlin negative G cutout too quick?

[41Sqn_Banks]

Originally Posted by JtD

The Mk.Va came with a float type carburettor. The Tilly orifice would only have an effect when flying at 12lb boost and 3000 rpm, if you did not do that, it was pretty much meaningless. If you did, however, the engine would continue to work under negative g just fine.

To me it sounds as if combustions stops during the inverted flight and the engine spools back up thereafter, which indicates the behaviour to be typical for a Merlin with a standard float type carburettor.

On the other hand the engine spools up quite nicely (though on a very rich mixture) immediately after returning to positive g's, so maybe a fuel flow restrictor (i.e. Tilly orifice) was in place. The Merlin handbook states up to 10 seconds of recovery after a neg g situation, which clearly isn't there.

Which Merlin handbook are you referring to? Don't you mean Pilot's Notes General? Standard procedure for inverted flying was close the throttle to allow a smooth recovery.