Author Topic: Inverted P-51 question..... (Read 4146 times)

Mace2004 · « **Reply #15 on:** April 06, 2007, 10:27:43 AM »

The term "Inverted" is a bit misleading. What's important is positive or negative G. As long as you have some positive G on an airplane it doesn't care if it's inverted or upright.

Kweassa · « **Reply #16 on:** April 06, 2007, 11:21:26 AM »

So why isn't any of this modelled in the game?

dtango · « **Reply #17 on:** April 06, 2007, 11:22:33 AM »

Probably only applies to 1-g inverted level flight.

Here are some Mustangs performing acrobactics that are in inverted or semi-inverted flight for 10+ seconds in some maneuvers. Pay attention to the opening and around the 3:00 min mark.

http://www.airshowbuzz.com/videos/view.php?v=022754bc

It's a great video anyway

. Gives a Mustang fanatic like me goosebumps!

Tango, XO
412th FS Braunco Mustangs

Mace2004 · « **Reply #18 on:** April 06, 2007, 01:09:42 PM »

Quote

Originally posted by Kweassa
So why isn't any of this modelled in the game?

I don't think it's really much of an impact, I don't know of many that do negative G for more than a few seconds anyway. The most important G effect on engines is modeled, that's the engine starvation in the carbureted planes like the Mk I Hurri and Spit.

Kweassa · « **Reply #19 on:** April 06, 2007, 02:17:14 PM »

Quote

I don't think it's really much of an impact, I don't know of many that do negative G for more than a few seconds anyway. The most important G effect on engines is modeled, that's the engine starvation in the carbureted planes like the Mk I Hurri and Spit.

Since when did flight/plane modelling accuracy rely on 'impact'?

Wolf14 · « **Reply #20 on:** April 06, 2007, 03:50:51 PM »

Ty Treize

Ack-Ack · « **Reply #21 on:** April 06, 2007, 05:30:44 PM »

Quote

Originally posted by Kweassa
So why isn't any of this modelled in the game?

IIRC, in another thread about this (this was during AH1 days), HiTech replied it had to do with game play issues. Do a search of the BBS for the original thread, it was really interesting.

ack-ack

dtango · « **Reply #22 on:** April 06, 2007, 11:22:23 PM »

Quote

Originally posted by Kweassa
So why isn't any of this modelled in the game?

Probably for the same reasons that the P-51B's guns don't jam during high g-maneuvers though being mounted at an odd angle in the wings...

...or why the A6M2 or A6M5 doesn't catch on fire much more easily compared to other aircraft because of unreliable self-sealing tanks...

...or why the Ki-84 doesn't lose engine horsepower from a faulty fuel line assembly that lead to a loss in fuel pressure which plagued it's career...

etc., etc.

Tango, XO
412th FS Braunco Mustangs

SAS_KID · « **Reply #23 on:** April 07, 2007, 12:44:00 AM »

Quote

Originally posted by dtango
Probably for the same reasons that the P-51B's guns don't jam during high g-maneuvers though being mounted at an odd angle in the wings...

...or why the A6M2 or A6M5 doesn't catch on fire much more easily compared to other aircraft because of unreliable self-sealing tanks...

...or why the Ki-84 doesn't lose engine horsepower from a faulty fuel line assembly that lead to a loss in fuel pressure which plagued it's career...

etc., etc.

Tango, XO
412th FS Braunco Mustangs

A6M's do catch fire easily.

AquaShrimp · « **Reply #24 on:** April 10, 2007, 07:50:41 AM »

Quote

Originally posted by dtango
Probably only applies to 1-g inverted level flight.

Here are some Mustangs performing acrobactics that are in inverted or semi-inverted flight for 10+ seconds in some maneuvers. Pay attention to the opening and around the 3:00 min mark.

http://www.airshowbuzz.com/videos/view.php?v=022754bc

It's a great video anyway . Gives a Mustang fanatic like me goosebumps!

Tango, XO
412th FS Braunco Mustangs

Didnt see any negative g maneuvers that lasted more than 1 second.

dtango · « **Reply #25 on:** April 10, 2007, 12:09:44 PM »

Quote

Originally posted by AquaShrimp
Didnt see any negative g maneuvers that lasted more than 1 second.

That's my point. So what does "inverted" mean exactly (as Mace points out)? The POH statement is not descriptive because if it meant any inverted attitude regardless of g then the real acrobatics involving inverted attitudes of 10+ sec performed by the Mustangs in the movie should not be allowed.

Tango, XO
412th Braunco Mustangs

frank3 · « **Reply #26 on:** April 10, 2007, 12:30:46 PM »

It sounds rather strange that a fighter aircraft, designed for air-to-air combat, wasn't able to fly upside down for too long.
You'd think the designers would think of that

Treize69 · « **Reply #27 on:** April 10, 2007, 01:10:12 PM »

Any piston aircraft ever built for combat will eventually either seize from lack of oil (or oil flooding the cylinders, depending on the type of engine) or conk out from fuel starvation if flown inverted too long.

Aerobatic aircraft don't have that problem, but they aren't usually built with redundant systems designed to survive hours and hours of constant high-performance operation at high altitudes either. Civilian aircraft are funny that way.

Since very, very little real combat takes place with negative G for more than a few seconds at a time (it puts a real strain on the pilot and the airframe, and its nearly impossible to shoot straight on your back), most aircraft never really have a problem with it.

gripen · « **Reply #28 on:** April 11, 2007, 02:23:06 PM »

I dug out the Corky Meyer's article on the Joint Fighter conference (Flight Journal WWII Fighter issue):

"The Seafire had such delightful upright flying qualities that knowing it had an inverted fuel and oil system, I decided to try inverted figure-8s. They were easy as pie, even hanging by the complicated, but comfortable, British pilotrestraint harness. I was surprised to hear myself laughing as if I were crazy. I have never enjoyed a flight in a fighter as much before or since or felt so comfortable in a plane at any flight attitude."

Anyway, the Seafire in the Conference might had had a some sort of special engine. There were two kind of lubrication systems in the Merlin and the late models got improved, so called end-to-end, oil system. That was supposed to be introduced in the Merlin 100 series (and V-1650-9 got it as well) but I don't know if it was used in the Merlin 55 of the Seafire III.