Merlin negative G cutout too quick?

[robtek]

Originally Posted by Fenrir

There is nothing more sinister going on here than crummps partisanship. For some reason there's a selection of people with an axe to grind against the Spitfire and Crummp falls particularly into this particular sorry species.

The fact is if he had done ANY research on ANY of the readily available tomes of the Spitfire (the volumes by Alex Henshaw and Jeffrey Quill for one, both Spitfire pilots and people with a far more qualifed opinion on practical aerodynamics than Crummp I am sure) he will know that the various quotes he has selected are, as typical, cherry picked examples of well known and quickly corrected faults with the Spitfire.

1) Spitfire Stability in Pitch: The Spitfire was certainly not UNSTABLE in pitch but the stablity it did have was MARGINAL. Big difference. as long as the CofG was kept within limits then the a/c was perfectly safe. The issues that affected only Mk.V aircraft of vicious spin characteristics and some strcutural failures were as a result of Squadron a/c being poorly loaded and supermarine directives not being followed at squadron level regarding the loading of new equipment and pushing the CofG out of limits. Bob weights and eventually a redesigned elevator mass balance actually cured this. See Quills book.

2) I suggest he actually reads Henshaws description of his fairly standard aerobatic routine that he was regularly called on to display and is accurately described in his book, Sigh for a Merlin:



Though according to Crummp that couldn't possibly have happened could it?

Agenda boi much!?!?!

I, at least, see your agenda, Fenrir.

Crummp says that the spits/hurris are not outfitted for inverted flight!

That is 100% correct!

That doesn't say that said aircraft cannot endure inverted flight for a very limited time.

To be outfitted for inverted (neg g) flight the engine must get metered fuel AND oil-pressure during the inversion.

Afaik all piston drive AC during that time only could endure neg-g, some better than the others.

[VO101_Tom]

Originally Posted by robtek

I, at least, see your agenda, Fenrir.

Crummp says that the spits/hurris are not outfitted for inverted flight!

That is 100% correct!

That doesn't say that said aircraft cannot endure inverted flight for a very limited time.

To be outfitted for inverted (neg g) flight the engine must get metered fuel AND oil-pressure during the inversion.

Afaik all piston drive AC during that time only could endure neg-g, some better than the others.

Many people do not know, but the DB 605 operating instructions also write, that prohibited the long inverted flight, because of the lubrication system.

I always was a bit astonished with the infinite inverted flight capabilities in old IL2...

[lane]

Originally Posted by VO101_Tom

Many people do not know, but the DB 605 operating instructions also write, that prohibited the long inverted flight, because of the lubrication system.

Motor und Triebwerksanlage des Flugzeuges sind nicht zur Durchführung von Rückenflügen geeignet. Hingegen ist Motor und Triebwerksanlage geeignet für Kunstflug in jeder anderen Form, wo nur ganz kurzzeitige Rückenlagen in Verbindung mit anderen Flugfiguren vorkommen.

[VO101_Tom]

Originally Posted by lane

Motor und Triebwerksanlage des Flugzeuges sind nicht zur Durchführung von Rückenflügen geeignet. Hingegen ist Motor und Triebwerksanlage geeignet für Kunstflug in jeder anderen Form, wo nur ganz kurzzeitige Rückenlagen in Verbindung mit anderen Flugfiguren vorkommen.

I have it in Hungarian, but the same thing there written:
"Műrepülés: Ezzel a motortípussal rövid ideig bármilyen műrepülést végezhetünk, háton repülést is. Kivétel a kizárólag háton repülés, amelyre a motor kenőberendezése nem alkalmas."

[lane]

Kunstflug: Mit dem Motor können jede Art Kunstflugfiguren auch kurzzeitig in Rückenlage geflogen werden. Ausgenommen sind reine Rückenflüge, für die das Schmiersystem des Motors nicht eingerichtet ist.

[JtD]

Originally Posted by robtek

Crummp says that the spits/hurris are not outfitted for inverted flight!

No, he says it is a cut scene from a movie that has nothing to do with reality. That's not only outright wrong, it's bordering insanity.