The A2A Simulations Community

Rate of climb seems to be way high after installing the 1.41 update, well over 3000fpm sustained at 160mph with all fuel tanks full and 35" @ 2,600rpm.

Temp was 70f with 41f dew point and 29.92".

The Accusim P-40 flight dynamics are not meshing with all the core updates from 1.3 and higher, at least for quite a few of us here. The affected among us are seeing the same kind of thing across the board, but A2A are preparing another update that will at least address some of these issues. They are testing the update now.

There are some other problems as well; I can't get close to the reported top speed of 360mph @ 16,000. Even with 40"mp and 3,000rpm with cowl closed, best I can do is low 320's. Hopefully Accusim v1.5 fixes the gross performance issues.

Some of the new stuff is pretty neat though. Love the high oil pressure until warmed up and the fuel return feed to the reserve tank is great. Not sure with this feature whether the wise tank sequence is start on reserve until almost empty then to fuselage then wing then back to reserve if necessary. Otherwise how would you be able to estimate how much is left in reserve ?

Burt, I've almost touched that top speed with the P-40, but by effectively making the prop' fixed-pitch by switching it to manual, and over revving the motor, this was done in level flight near sea level, I only tried this the once, and was not able to sustain it for long before the motor sounded like it was going to shed parts.

John.

- edit - having a ganders around the 'net ~360mph+ @15/16,000 appears to be for the E variant. Figures for the other types are a little less, speed-wise.

I wonder if top speeds would also be greatly affected by temperature, humidity, weight, and fuel-grade. I'm sure others will know the details.

http://www.historyofwar.org/articles/weapons_P-40_stats.html

Figures vary a little from source to source.

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~ Make love to the sky, don't shag it.

In the B model, I start/taxi/runup/takeoff with Aux tank. After 5 mins or so switch to fueslage tank. If fuselage tank is empty, switch to wing tank. That way I can use the fuel gauges until they are empty...switch back to aux, start looking for places to refuel...using the red low fuel light as an idication to land 'soon'. Unless I plan on a long cross country flight, I keep the Fuselage tank empty for better CG and stability. If I were in the C model, I would go Aux(start/taxi/TO/+5min)->Fuselage->Drop->Wing->Aux

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"The knack of flying is learning how to throw yourself at the ground and miss." - Douglas Adams

Rusty, can you get close to 360 mph at 16,000 with the 1.4 update ? That is the figure in the A2A manual. I think I could get very close to that before with mp and rpm near redline and cowl closed. I can't get 325 now. Interestingly I can get more speed at a higher altitude where I expected less speed.

No maybe the mph number in the F2 panel is wrong.

I use the virtual 'pit only, without the tooltips - I'm away from my PC at the moment, when I'm back I'll see how close I can get to that speed @FL160. It shouldn't do 360mph though, as that's recorded for other variants, like the E, but i'll push it as far as I can.

_________________
~ Make love to the sky, don't shag it.

Perhaps I can elaborate here

P-40B (Tomahawk IIa)
Max Speed: 352mph @~ 15,000ft/15,500ft
Climb Rate: 2860ft
Ceiling: 32,400ft
Empty: 5590 lbs
Gross: 7326 lbs
Maximum: 7600 lbs

P-40C (Tomahawk IIb)
Max Speed: 345mph @~ 15,000ft/15,500ft
Climb Rate: 2650ft
Ceiling: 29,500ft
Empty: 5812 lbs
Gross: 7459 lbs
Maximum: 8058 lbs

These are just figures however and one must understand what Accusim and A2A do and it is not just about achieving within 1% of a specific static figure but a range of figures as the result of numerous factors. There may be many reasons why at present the models do not match the figures including updates and bug fixes.

The 360mph is indeed the P-40E figure. Currently I used to get around 346mph on all variants on the 1.2 patch. Now I get around 333mph top speed and yes the climb rate up to at least 8000ft is a bit too good, I too get around 3000/3200ft a minute until the climb rate bleeds off around 12,000ft. Also it is apparent to me that all the models are the same in terms of flight performance, there being no major differences in climb rate and top speed between the B and C (Tomahawk IIb) variants. However there may be good, even intended reasons for this including the fact that the variants are not too dissimilar anyway

Either way one must give great credit to A2A This is a small nit picking grievance in view of the fact that the A2A P-40 represents the most accurate P-40 ever designed for FSX, and it is perhaps without the climb rates and top speeds pretty much as real as it gets (everything else 99.9% of everything is great and works 100% accurately) One must also consider how difficult it is to replicate these things. Also the earl P-40 models are difficult to find information on, I am surprised A2A did not indeed do the P-40E or later models as they would have been much easier to develop. The poor quality and quantity in general of flight performance data of all USAAF and USN aircraft is apparent, with only relatively few popular examples like the P-47 and P-51 easy to find. A lot of the information appears to have been destroyed unlike similar information one would find on the RAF aircraft conducted by the Aeroplane and Armament Experimental Establishment, infact much of the best information on US WWII aircraft concerning flight performance is referenced to such and can be found all the way at the National Archives at Kew, UK (I love the UK )

Also one must understand that one change in one piece of code can lead to another piece of code breaking out of line.



Regards,
Colin