Primarily for general aviation discussion, but other aviation topics are also welcome.
User avatar
By MichaelP
#1698737
I’ve flown inverted in the Chipmunk and in the T67A neither of which has an inverted system or fuel injection.
In ‘Some Mothers Do ‘ave Them” Michael Crawford flies the Cessna Aerobat inverted.

What’s the problem?

You close the throttle, have enough speed, and when you finally roll level you gently open the throttle again.
Usually you will get a puff of black smoke as the initially rich (flood) mixture clears.
User avatar
By foxmoth
#1698754
What’s the problem?


No problem - but in the film the engine kept running - that won’t happen in a Chippie!
User avatar
By mikehallam
#1698797
Probably a useless addition to this discussion.......

But my carburetted chain saw runs at all angles (inc. inverted) with a diaphragm device; perhaps in WWII they too were up to it ?

mike hallam.
User avatar
By Lowtimer
#1698946
joe-fbs wrote:It's a film, they could have added the engine noise later.


They absolutely would have. But for that inverted flight past they added the whole Hurricane later. I've just watched it and while the flying before and after that inverted run is the real thing, the two shots of prolonged inverted flight area fairly obvious model shots.

The second shot of the inverted flypast cuts to a reaction shot of dude looking on admiringly from the wing of his own Hurricane (studio mock-up shot, note it's in the tail-up attitude, same with the guy watching from his cockpit on the ground) and then the roll back to level flight with a puff of smoke is back to the real thing, being the second half of a slow roll.

They then do a final low level run in, and repeat a shot of the same complete slow roll used earlier in the sequence.
User avatar
By MichaelP
#1699106
Experience with the Slingsby showed that if you did not close the throttle when inverted the initial dump of fuel would slowly be consumed and then as the mixture became acceptable the engine would suddenly produce power.
Maybe not so bad as the crankshaft was now in the ‘oil pan’ but not a good idea as there was no oil pressure.
Always close the throttle when inverted flying a float carburetted engine.

Except the BÜ131B, its HM504 engine had a carburettor with two floats, one for upside down flying, while a flame would come out of the exhaust when the g was zero, or passing knife edge.

The Stampes and Super Tigers had a crude fuel injection system for inverted flight, but no inverted oil system.
You switched the fuel off to the carburettor, then when the engine faltered you moved the mixture lever up beside the throttle and moved both levers together.

I always wondered why the O 240 in the Cessna F150, and the D62C Condor tug was rated at 130bhp while the injected IO 240 in the DA20-C1 is only 125bhp.
Fuel injection means poorer starting, and lower power in an aircraft engine...
I wonder if Me109s had more difficulty scrambling as fuel injected Continental and Lycoming powered engined aircraft have today?
Maybe they did running reload, refuels?
User avatar
By Paul_Sengupta
#1699112
MichaelP wrote:Fuel injection means poorer starting, and lower power in an aircraft engine...


Not necessarily. The carburetted Lycoming O-360 has 180hp. My fuel injected one has 200hp. However that is mostly because fuel injection also allowed the compression to be increased from 8.5:1 to 8.7:1.
User avatar
By Desert Rat
#1701583
The earlier marks of Merlin (Mk3 etc) fitted in early Spits and Hurricanes could be flown inverted for a short period with little issue (slow roll, slow 4 point roll etc), it is when increased negative G was applied that the fuel starvation became a problem, hence the 'Miss Shillings Orrifice' addition.