View Full Version : P-40 model and name clearification.

03-13-2007, 06:42 PM
Hi all!

I got to looking into the names and models and wanted to see if I have a clear understanding.

Here is what I found.

Curtiss Model....USAAF....British............Export
Model 81..........P-40......TomahawkI.....H81-A1
Model H81-B......P-40B....TomahawkIIA.....H81-A2
Model H81-B......P-40C....TomahawkIIB.....H81-A3
Model H81-B......China Hawks (AVG)........H81A-2 (not typo)

RAF serials were AH991/999 (all to USSR), AK100/570 (36 to China), AM370/519 (64 to China), and AN218/517.

Check this out:
There persist to this day some confusion about which version of the Tomahawk that was actually delivered to China. Was it the Tomahawk IIA (equivalent to P-40B) or Tomahawk IIB (equivalent to P-40C)? Curtiss company records list them as Model H81-A3, which would seem to make them Tomahawk IIBs (equivalent to the P-40C). There are some discrepancies between Curtiss records matching Tomahawk designations to RAF serials and to equivalent US Army P-40 models, so there is confusion on this point. However, the AVG planes couldn't be Tomahawk IIAs, since only 172 of these were built and there is no record of any of them being delivered from the RAF to China. Therefore, many historians have concluded that the AVG planes had to have been Tomahawk IIBs, which would make them equivalent to the USAAF P-40C. However, Erik Shilling, who was a member of the AVG and who was also a flight leader and an engineering officer for the group, maintains that the airplanes with the AVG were actually export models of the P-40B and not the C. After all, he was there and he ought to know! He says that the Flying Tiger airplanes did not have the equipment to carry the external 52-gallon drop tank, nor were they equipped with bomb shackles. In addition all of the fuel tanks had external self-sealing material, not internally-mounted sealing material as in the "C" model. Also the Model "C" had armor plate in the front, ahead of the pilot, installed on the firewall between the two fifties, but the AVG's planes did not.

The resolution of the problem seems to be be in the fact that the AVG Tomahawks were actually built to a special order. The planes were indeed diverted from Tomahawk IIB contracts, which was equivalent to the P-40C, but when the the planes were actually built they were equipped with the externally-sealed fuel tanks that had been used on the Tomahawk IIA. It seems that Curtiss had some surplus externally-sealed fuel tanks lying around that the British did not want, and decided to use them on the Chinese contract. In addition, the Chinese contract did not specifically ask for plumbing or shackles for an external fuel tank, so this was deleted. Consequently, the AVG Tomahawks were functionally equivalent to Tomahawk IIAa, even though they were taken from a Tomahawk IIB production batch. So they are basically P-40Bs and not P-40Cs.

Cool huh?

I'll stop there. What you guys think? Any other feedback?

03-13-2007, 06:48 PM
This is pretty much what I've found

Guys like Dan Ford have uncovered a lot of info on this stuff

This may interest you as well:


03-13-2007, 06:54 PM
Cool stuff cid...is this why Oleg has the H81-A2 for the China Hawk and not the TomahawkIIB? What I mean is....the fact that the China Hawks "Flying Tiger airplanes" did not have the equipment to carry the external 52-gallon drop tank, nor were they equipped with bomb shackles as did the TomahawkIIB?

Also, noted and changed..."The difference between these two models was that the H81-A2 had fuel tanks internally sealed instead of external, it had shackles that could carry a 500 pound bomb, and was plumbed for a 52 gallon belly tank for longer range, and armor plate was installed between the two forward firing synchronized fifties.

Unfortunately on the later P-40C, had a big draw back in that it was that the slowest of all of the P-40 built. The AVG's H81A-2 was 355/360 mph at 14,500 feet compared to the H81-A2's speed of 340 mph. Since the Allison's on the AVG's airplane developed higher HP than the Standard Allison, it is quite likely that the AVG's fighter had a top speed in the 370 mph range."

03-13-2007, 08:30 PM
Well, the reason that we have the H81A-2 as the AVG plane is that the Flying Tigers were simply not known to Oleg and it was a late addition. In general, the H81A-2 is simply the "non US Army" P-40B, the version for export sale. Britian could call the plane whatever they liked, but it was still an H81A-2 in essense, with equipment specified by the RAF, and installed, sort of like options on a car I suppose

What really went into the AVg planes, which fuel tanks, where the guns came from, why some equipment was missing, if it was the two gun or one gun wing originally...I don't think anyone will ever know for sure, and it's probable that some planes had unique aspects. It's possible Curtiss itself was confused in 1941, and that's why the airframes got the unique model number

It's interesting to note that historicans like Carl Molesworth and Terill Clements refer to the planes as "H81A-2s" and "H81-A-2s". Personally I think somebody over at Curtiss got fed up with the 'custom' aspect of the RAF order transferred to China, and simply used a new number to keep track of what was what and keep a clear paperwork record. They were using any old parts sometimes...internally sealing tanks, externally sealing tnaks, some AVG pilots claim there were no self sealing tanks...it's likely that Curtiss was using up old inventory to clear room in it's warehouses

03-14-2007, 06:49 AM
Thats what I think...Curtiss used up parts that were not wanted by British nor USAAF specs. Saw where they were assembled (built) in a separate **EDITED*** "assembly line" to keeps the parts from getting "mixed up".

The H81 number is certainly the Curtiss Model number. I see where the model number is wrote different depending on who is telling the story. Looks like China ordered 100 of the H81-A3 but got modified TomahawkIIbs, the H81-A2s maybe re designated H81A-2 to keep confusion down when assembling the fighters. We may never know the truth. Its no big deal of course, I just like to know details. Definitely a nice story nevertheless!

03-14-2007, 10:28 AM
Oh, there's no doubt about the basic Curtiss model number. H81 was the model. The designation after that is the trouble http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif For example, the P-40E was, if I recall, the H87 model

The prototype Hawk 81 was made from the tenth H75, taken from the assembly line and modified with an inline engine. The Brits called their H75s "Mohawks"

03-14-2007, 03:19 PM
Same thing with the famed Curtiss P-6E Hawk. Take a look here...BTW is my webpage!
Curtiss P-6E Hawk (http://www.curtisshawkp6e.com/_mgxroot/page_10774.html) Which is were my callsign came from http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif