Merlin negative G cutout too quick?

[JtD]

Originally Posted by ZaltysZ

Engine starves briefly at first and then gets flooded with fuel, because things get reversed: the more fuel you have in float chamber, the more fuel you get into it. Tilly orifice simply restricted fuel flow to amount engine needs at max power setting, so even when things are reversed, float chamber gets no more fuel than engine can burn (at max power setting). Lower the fuel usage (cut the throttle or lower the RPM), and Tilly orifice won't prevent the flooding anymore. Without orifice things are the same, except engine gets flooded even at max power setting.

Running engine at max RPM and open throttle softens the flooding by some extent, but recovering with same settings can indeed result in overrev. It is probably better to cut the throttle just before recovery and not the moment cut out occurs - this seems more optimal.

Yes but...

if you cut throttle there's less air flow to suck the fuel out of the jet nozzle, so the engine does not get flooded as much. It's true what he said, it was recommended to cut throttle during neg g manoeuvres, in order to get the engine "get going earlier".

Throttle also had to be reduced and was not to be applied quickly due to low oil pressure in (longer) neg g manoeuvres.