Mustang MkIII?

[Voyager]

So, some background to start, this all started with me trying to figure out how to deal with FW-190D-9's in a P-51. I was messing around in Il-2 compare v4.07, when I noticed the MkIII had high performance at sea level. I used HardBall's Aircraft Viewer 4.08 and found the following top speeds at sea level listed:

P-51B: 577km/h
P-51C: 580km/h
P-51D: 592km/h
Mk.III: 636km/h

What is it that makes the Mk.III 40km/h faster at sea level than any other Mustang in game? In fact, looking at it, it looks as though it has the highest speed at sea level of any of the conventional engined planes. Did the British use a lower altitude supercharger on their version?

Harry Voyager

[IvanK]

+25Lbs Boost ... or 75" MAP v the usual +18Lbs Boost 67" MAP in the stockmachines.

The higher boost only available with 150 Octane fuel.

[Voyager]

Originally Posted by IvanK

+25Lbs Boost ... or 75" MAP v the usual +18Lbs Boost 67" MAP in the stockmachines.

The higher boost only available with 150 Octane fuel.

Are you sure that's all that's going on in that one? The P-51B/C out perform it at higher altitudes. The curve looks more like an extension of the P-51D-20, than a C model.

Actually, let me re-ask that. Is the MkIII based off of the D's flight model, or the B/C's flight model?

Thank you,

Harry Voyager

[IvanK]

Thats exactly it the +25Lbs Boost is only available to a lower Full Throttle height than the standard +18Lbs boost At the higher levels performance should be much the same. Give or take a tad depending on Engine Full throttle height ratings.

The Mustang III is simply a B/C with more power at the lower levels and a slightly differrent Supercharger schedule.

The game uses the extra power in the FM though the MAP guage still reflects the lower rating. The MAP guage indications are earmarked for correction in the Mustang III.

What you see in IL2 Compare is close but not exactly what the FM sees.

[Voyager]

I probably wasn't very clear in what I was saying. What I was tryingto say was that the Il-2 Compair has the P-51C with a Speed of ~730km/h at 8km, with the Mk.III doing about 715, while the Mk.III does about ~730 at 6.5km. The P-51D did about 710km/h at 8km, which is why it looked to me more like the P-51D with boost, than a P-51B/C with boost, but if Il-2 compare is a faulty witness, this means flight tests!

Don't you just love having an OCD fanbase?

So I finished a basic round of testing, 25% fuel, no overheats, unlimited fuel, and no cockpits, over MTO, at 7500m +500m advantage, and the results are:
P-51B: 740-750 km/h
P-51C: 745-755 km/h
Mk.III: 736-745 km/h
P-51D-5: 730-740km/h

So, not much difference really, other than the D, which is sort of slow. They're all within the margin of error.

And continuing in the meme, I finished the P-51D-5 fight with a dive test, starting at 729km/h at 8km (I'd hit a thermal crossing the Itialian coast)
8km: 729km/h
7km: 827km/h Note: this was the first point at which the plane was full veritcal
6km: 951km/h
5km: 1061km/h
4km: 1141km/h
3.5km: 1166km/h Note: this was approximatly the alltitude/speed at which my tail fell off.
2.6km: 1189km/h Note: Now a wing comes off, and things go downhill from there.
0km: 0km/h Note: PK