The A2A Simulations Community

Hey guys, I've got a few questions here again about the P-40. This time it's about several discrepancies between the official POH, and the aircraft in the simulator.

I just finished reading the P-40 POH from start to finish, and I jotted down some notes about things I noticed that mismatch the A2A Simulations P-40. Hopefully I can get an explanation as to why these are there. I know the A2A P-40 is a very early model, but the POH seems to account for the model differences when applicable.

So here we go.

1) The fuel quantities do not match. The A2A P-40 has a total fuel quantity of 135 gallons. The POH says it should be 148 for earlier P-40s (before the N model).
2) The coolant quantity in the POH says it totals 3.7 gallons. The A2A totals 14.1 gallons.
3) The wing tanks should read 10-15 gallons less than their actual quantity when at rest on the ground according to the POH. The A2A P-40 reads full fuel in the wing tanks, even at rest.
4) Why doesn't the prop need to be rotated to mix the oil? The POH says it should be cycled around. I know you guys implemented this into the Cub.
5) There is only one emergency hydraulic valve in the A2A P-40. The POH says there should be two, one on the left, and one on the right.
6) The A2A manifold pressure has a red radial line at 41", and it's A2A's suggested takeoff power. The POH suggests a takeoff power of 45".

I'm gonna hit the hay. I stayed up until the wee hours of the morning reading that handbook. Gotta love old USAAF books though. So much different than USAF handbooks today.

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My Guide On How To Fix Your X-52's Rudder!

Given A2A did their research on real material (including real aircraft and manuals etc..) I would guess they got their data right no?

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Lukas

Don't know about the others but there are 2 emergency valves in the P-40 but the one on the right is out of sight due to its location under the seat but it's there. Turning the left valve also turns the right I believe. I think this was mentioned in the accusim manual.

636,

1) The fuel quantities do not match. The A2A P-40 has a total fuel quantity of 135 gallons. The POH says it should be 148 for earlier P-40s (before the N model).
The P-40N is a very late model, so they may be referring to the E/F models. We used the P-40B manuals that show fuel capacities to be 132.6 imp / 159 us gal. Also note the Tomahawks and P-40C’s have self-sealing tanks that reduce capacity.

2) The coolant quantity in the POH says it totals 3.7 gallons. The A2A totals 14.1 gallons.
3.7 gallons of coolant wouldn’t have a chance of cooling an engine of this size. The manual is speaking of the cooling tank, whereas we are showing all the coolant in the system, including the engine, radiator, and lines.

3) The wing tanks should read 10-15 gallons less than their actual quantity when at rest on the ground according to the POH. The A2A P-40 reads full fuel in the wing tanks, even at rest.
We modeled the pitch changes for the Spitfire, but we chose to model the sloshing physics for the P-40 and beyond.

4) Why doesn't the prop need to be rotated to mix the oil? The POH says it should be cycled around. I know you guys implemented this into the Cub.
On any aircraft, if you choose to not rotate the prop and just fire the engine up, it will start and run normally. It is just, over time, it will wear down more if you immediately jump to start a motor w/o cycling the prop. Accu-Sim does model this, and you can do this by keeping the mags off for a few seconds after engaging. On the P-51, for example, you count 6 blades before turning on the mags for this purpose.

5) There is only one emergency hydraulic valve in the A2A P-40. The POH says there should be two, one on the left, and one on the right.
They are both there, but one is out of view. You can see it if you move your viewpoint forward and look down to your right. So, when you click on the valve, you will notice the other valve opens as well.

6) The A2A manifold pressure has a red radial line at 41", and it's A2A's suggested takeoff power. The POH suggests a takeoff power of 45".
This is different based on the engine variant you have, and can vary based on application. We used 41” for the -33 engine. You can use 45" for short periods, but make sure you have 100 octane.


Scott.

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A2A Simulations Inc.

Did that answer your question, son?


(just a light hearted ribbing to 636Castle; sorry couldn't resist)

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1)i7 980x 4.35 ghz, gtx 470s SLI, Matrox th2go, Creative x-fi
2)i7 2600k, Gigabyte z68x, gtx 285s sli

I have great admiration for A2A, Scott and his team. I was glad to see that some apparent discrepancies actually weren't discrepancies at all.
Having said that, I also admire 636Castle for doing the homework and reading the POH and bringing these things up. I'll bet Scott and crew encourage this type of thing- not only does it point up the fact that their products are extremely well researched, but it could also conceivably uncover something they may have missed, which I am sure they would correct if it could be substantiated.
Keep up the good work Scott- AND 636Castle!

Thanks Scott!

I wanna start getting to know these warbirds inside and out, and all of those things were going to bug me if I couldn't turn around and give explanations to somebody else if they asked me the same things. I guess the fact that we're reading different manuals for earlier/later P-40s might have something to do with it.

Happy Mother's Day to everyone.

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My Guide On How To Fix Your X-52's Rudder!

636Castle,

You will find this of some interest:
http://www.keyos.org/avia/usa/curtis_to ... anual1.htm
http://www.keyos.org/avia/usa/curtis_to ... anual2.htm
http://www.keyos.org/avia/usa/curtis_to ... anual3.htm
http://www.keyos.org/avia/usa/curtis_to ... anual4.htm

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1)i7 980x 4.35 ghz, gtx 470s SLI, Matrox th2go, Creative x-fi
2)i7 2600k, Gigabyte z68x, gtx 285s sli

That is why i am a proud customer of A2A accusim. The whole developement team know what they do, and why. To develope at an high standard you need people in the team, or the team takes several system specific specialists for each real system to know how that all works - and why it has to work like this.

I like it

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FSX SP2 DX9.Addons:FSG2010,REX OD, AS2012, PMDG, DA Do27, Dodosim, A2A accusim all, Katana4X,Coolsky DC9 Classic, Swiss Pro,ORBX all, Fly Tampa, DRZEWIECKI DESIGN, FS Dreamteam, FranceVFR Haute Normandie 3D...

Also be aware guys that, without exception, the WOP3 birds are researched with not only the Pilot's Notes (POH, if you like) but with the E&M's as well. Often the Pilot's Notes will give slightly vague or imprecise information that can sometimes be misleading (the US notes less so than the British), after all, they are for Pilots, not engineers. With the E&M's the aircraft can literally be assembled or torn down, piece by piece and these clarify any misleading information and give the exact lengths, volumes etc etc. Often several different versions are examined and changes tracked as there are often variations between serial ranges of the same model and more often between manuals for the SAME aircraft at different dates!! (As and aside, the AVG took British manuals to China as they had "hijacked" British allocated Tomohawks...so their manuals are quite unlike the equivalent US manuals)

As an example, I re-read almost my entire collection of Spitfire PN's and E&M's (OK, I skived off and didn't re-read the Griffon models ) along with the Merlin engine manuals and "E&M" equivalents for the Merlin I/II, III, XII, XX, XLV, 45M, 50, 50M, 60, 61, 70, 71... while researching the WOP3 Spitfire I/II....Also 35,000 General Assembly (Engineering Drawings) provided the dimensions, placement and characteristics of every piece that needed modelling (for instance, the diametre of the cooling vent hole and the length, angle of bend and degrees of movement of the Mk I undercarriage pump handle.

That is the sort of research and detail that has gone into the WOP 3's and that tradition continues with the Mustang...oh..damn, sorry, forget that..not allowed to talk about the M.U.S.T.A.N.G. in front of the C.H.I.L.D.R.E.N...

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...Some say he never blinks, and that he roams around the woods at night foraging for Merlin parts...

Really hot day here in Washington State. Mid 80s.

I loaded her up and checked my oil temperature...a little below 80 degrees while cold!

By the time I got her running, I barely had any time to do a quick ground check before she was red lining at 85 . I got up in the air quickly, and did a few dives to get the radiators cooled...finally my coolant was down to about 85 and my oil temperature dropped to about 78.

I kept my shutter fully open during the entire 30 minute flight, came back, and shut her down. My prestone had stayed nice and cool from the wind, now my engine is colder after flying than when I did a cold startup! Haha. Around 60!

Might considering servicing with 1120 oil early if we keep having these warm days.

Also I've programmed my starter to a switch on my joystick. Makes it way easier to prime and enrich the mixture all together while throwing the starter.

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My Guide On How To Fix Your X-52's Rudder!

636,

Keep in mind, using autostart automatically warms the engine.

Scott.

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A2A Simulations Inc.