help flying the corsair

[dflion]

Last year I drew up a 'prop pitch' diagam to help my son better understand the principles of manual prop pitch as it applies to aircraft in IL2 - 'a picture is a thousand words'.

The percentages I have used in this diagram may not suite every aircraft using manual pitch in IL2 - you will have to experiment with the Corsair. I used the excellent Tempest as the basis for these percentages.

You can type in to your aircraft controls in the game the 'Shift values' I have shown. 'Fine pitch' (higher rpm) is used for takeoff and landing. 'Course pitch' (lower rpm) is used for fast cruise and air combat. You will need to experiment with various aircraft to really understand how varying pitch will help through the whole range of flight - stationary, taxying, take-off, climbing, air combat, descent and landing.

I have also included real pilot notes on prop pitch for the Spitfire II. Later Mk's of Spitfires had their throttles linked to the prop pitch mechanism, which could be overided.

Anyway I hope this diagram helps you understand how it all works.

DFLion

[Shrike_UK]

Yes very good examples of the propeller pitch guys ^^, i particularily like the part about thinking of it as gears in a car 100% like 1st. However, my point was just about landing, and i still beleive its best to run a low prop pitch with higher throttle. Think about this, and even test it...

Which is fastest to gain speed if you are too low and about to hit the back of a carrier:
Landing @ 40% Throttle with 20% prop pitch
Landing @ 20% Throttle with 100% prop pitch

Time for Throttle to reach 100-110% will be less if the throttle is already at 40%, and the prop pitch takes less time to adjust to 100% than the engine spool up. This means your acceleration will be faster for an emergency abort. It also allows for fine tuning of your speed on landing using prop pitch rather than throttle.

I maybe wrong and feel free to correct me, but in either case above that you guys have talked about, general flight and takeoff. Is there any particular reason why you would want 100% prop pitch on landing? As far as i can think of the only result would be increased drag, (as your descending) and increased engine labour as you throttle from 20% to 110%.

@dflion, the picture you've given, thanks for that, is interesting as is shows 50% prop pitch as being a good setting for takeoff. however would this be incorrect for carrier takeoffs where you need maximum acceleration or you end up in the sea?. Thanks and i really fancy trying out your values in your diagram now and see if its better. I hope im surprised!

[TheGrunch]

My knowledge is restricted to aircraft with constant speed propellers, but as far as I know it's the other way around. Engine RPMs take far longer to respond than manifold pressure - try flying the Spitfire IX, set to manual pitch (Shift+0). Set prop pitch to 0%, then to 100%, and watch how long it takes for engine RPM to change. Then change the throttle setting, and watch the boost gauge. It should move almost instantaneously. When you say it takes longer for the engine to 'spool up', you're right, because the engine revolutions do take longer to change, but given for that the majority of the aircraft in the game, prop pitch controls the governed RPM, not the actual propellor pitch, this means that it takes longer for 'Prop Pitch' to change the engine's functioning than 'Throttle'. So for landing, better to have Prop Pitch set to 100% and vary the throttle since you'll already be operating at max revs if you need to go around.

[dflion]

Thanks Shrike_UK, its all about experimenting with each IL2 aircraft, they are all different in weight and power values. You will find a 'happy medium' in the prop pitch percentages for each aircraft.

Just a note about your reply 'TheGrunch' - you are right about prop pitch governing RPM. For the Tempest, I use a 'finer pitch' of 50% and this gives me a slower initial take-off speed yet a higher RPM which gives me more control of the aircraft. The same situation applys for landing. Fine pitch was used by most WWII aircraft for take-off and landing - higher RPM - more control. You can use a courser pitch of 100% or 90% for take-off and landing, though theroretically you have less RPM and less control.

For Ctrl E on the subject of Superchargers for the F4U - quote straight from IL2 1946 aircraft pilot notes " Switch supercharger speeds at 2,600m (8,500ft) and 8,200m(26,900ft)". I have also attached real pilot notes from the Spitfire IX explaining supercharger operation. I would also recommend Googling Wikipedia under 'aircraft superchargers' for a very comprehensive explanation on how superchargers and 'turbo' supercharges work on WWII aircraft.

[TheGrunch]

Originally Posted by dflion

Just a note about your reply 'TheGrunch' - you are right about prop pitch governing RPM. For the Tempest, I use a 'finer pitch' of 50% and this gives me a slower initial take-off speed yet a higher RPM which gives me more control of the aircraft. The same situation applys for landing. Fine pitch was used by most WWII aircraft for take-off and landing - higher RPM - more control. You can use a courser pitch of 100% or 90% for take-off and landing, though theroretically you have less RPM and less control.

100% Prop Pitch in the game = Max RPM, so I don't see what you mean. The reasons I can see for dabbling with prop pitch in an aircraft with a CSU are to gain more speed in a dive, prevent the prop overspeeding in an abrupt powerdive or for fuel economy and oil/radiator coolant temperature reasons, although for some reason I HAVE always felt more comfortable flying the with prop pitch on manual. You CAN get an extra jot of speed by reducing pitch slightly when you're fast and level, but other than that, 100% in combat most of the time, and definitely for takeoff, landing and maximum climb rate.

[dflion]

Originally Posted by TheGrunch

100% Prop Pitch in the game = Max RPM, so I don't see what you mean. The reasons I can see for dabbling with prop pitch in an aircraft with a CSU are to gain more speed in a dive, prevent the prop overspeeding in an abrupt powerdive or for fuel economy and oil/radiator coolant temperature reasons, although for some reason I HAVE always felt more comfortable flying the with prop pitch on manual. You CAN get an extra jot of speed by reducing pitch slightly when you're fast and level, but other than that, 100% in combat most of the time, and definitely for takeoff, landing and maximum climb rate.

I have just had a test fly of the Tempest and explored the prop pitch situation in the game. The diagram that I originally posted was taken from an English 'Aeroplane Mag' - I know that the finer the prop pitch is, (see diagram) the higher the RPM. And if you set a courser pitch the lower the RPM (real WWII aircraft situation).
What I have noticed, in the take-off situation, Oleg and Co. may have reversed this situation in IL2 (he may have resolved the situation in BOB) - if you set the pitch to 100%(course) in the game the higher the RPM.
Once the aircraft gets to altitude in IL2, the courser the propellor pitch (100%), the aircraft travels at higher speed - good for combat. It appears that Oleg may have compromised the situation for the sake of gameplay?
I have a friend that flys a real Kittyhawk and Spitfire at Temora NSW Australia - I will try and contact him to further discuss this situation.
Anyway we have a real discussion point in this thread. Suggest you 'test fly' the Tempest and see what you think?

DFLion

[TheGrunch]

Originally Posted by dflion

I have a friend that flys a real Kittyhawk and Spitfire at Temora NSW Australia - I will try and contact him to further discuss this situation.
Anyway we have a real discussion point in this thread. Suggest you 'test fly' the Tempest and see what you think?

DFLion

I don't think it's really an issue, all you need to remember is that Prop Pitch actually just means RPM. It's like the propeller control lever in an early Spitfire IX. It should be called Governed RPM or just RPM.