Curtiss XP-21...

[lark]

Is there any one of the specialists who ever have seen or who have an illustration
labbeled as Curtiss XP-21 fighter.

The XP-21 was a XP-3A (26-300) fitted with the new
300Hp Pratt&Whitney R-985 Wasp Jr. engine.

Only one XP-21 constructed.

Despite years long search in published sources (Book- mag's -series-libraries ) not a single
illustration of the XP-21 fighter was located...

Thanks in advance.

 

[hesham]

My dear Lark,


I saw a drawing to it,90 % in a magazine,but you know my memory.

 

[lark]

Do you have a hint about that ? magazine Hesham...
(English , American, French , Deutsch..)

 

[hesham]

My dear Lark,


may be Le Fana,L + K or a Russian magazines,for the last one,leave it to me,I will search about
all Russian magazines I have.

 

[joncarrfarrelly]

According to Bowers Curtis Aircraft 1907-1947 and Dean/Hagedorn Curtis Fighter Aircraft
there were two XP-21, the first converted from a P-1A (26-300), the second from a P-3A (28-189).

P-1A (26-300) - R-1454 Pursuit (Curtiss R-1454 engine) - XP-3A (R-1340-3) - XP-21 (R-985-1)

P-3A (28-189) - XP-3A (R-1340-3, NACA cowl development, racer) - XP-21 (R-985-1) - P-1F

The only real visual difference, sans cowling/speed ring, would be in the smaller diameter of the R-985.
The big question is, was the R-985 on the XP-21s full-cowled, partially cowled, speed/Townend ring
or none of the above. ;D

 

[Jos Heyman]

In December 1930 two XP-3As were converted as XP-21. They had serials 26-300 and 28-189. Aircraft 26-300 was later converted with a Wright R-975 engine and was redesignated as XP-21A. The other aircraft was modified to P-1F standard.

I do not know the source of the enclosed photo.

 

[Arjen]

The big question is, was the R-985 on the XP-21s full-cowled, partially cowled, speed/Townend ring
or none of the above. ;D

...and there's your answer.

Jos, nice find. All the books I looked at had the same irritating gap: images of P-20, P-22 - and always the P-21 missing.

 

[lark]

Thanks both Johnc and Jos H.

As was indeed aware that 2 airframes were used for the XP-21 fighterprototype.
I'll check my files , maybe I can locate the source for the pic that Jos posted..

 

[lark]

The picture posted by Jos Heyman shows us the initial version
of the Curtiss YP-20.
The airframe ,less engine, was almost identical to the P-6/P-6A exept for the tailwheel.
There were also more refined versions with faired landing gear strutts and wheel pants.

Same pictures in:
Forgotten Fighters and Experimental Aircraft part II - U.S.Army 1918-1941. p.64
by Peter M.Bowers.

There's also an illustration of in : United States Military AC since 1908. Putnam.

The search for a XP-21 illustration continue's...

 

[hesham]

My dear Lark,


I have more than 800 of Russian magazines,so the searching will take sometimes.

 

[lark]

Think there is a bigger chance in U.S magazines or books
rather than in others Hesham.

For exemple : Le Fana issue Nr.1 to Nr.100 produced no results..
(nor did the many books about U.S. Fighters (paperversions) which I consulted)

 

[Stargazer]

Being quite the Curtiss buff myself, the XP-21 has always resisted my investigations. I was kind of surprised that a photo of it even showed up in this thread, because I have none in the numerous books/magazines I have on Curtiss or U. S. military aircraft.

 

[hesham]

My dear Lark,


as you said,in US magazines or books is the big chance,but also British magazines
can be consider.

 

[Steve Pace]

In December 1930 two XP-3As were converted as XP-21. They had serials 26-300 and 28-189. Aircraft 26-300 was later converted with a Wright R-975 engine and was redesignated as XP-21A. The other aircraft was modified to P-1F standard.

I do not know the source of the enclosed photo.

Pilot's eye visibility is non-existent to say the least. -SP

 

[Arjen]

The picture posted by Jos Heyman shows us the initial version
of the Curtiss YP-20.
The airframe ,less engine, was almost identical to the P-6/P-6A exept for the tailwheel.
There were also more refined versions with faired landing gear strutts and wheel pants.

Same pictures in:
Forgotten Fighters and Experimental Aircraft part II - U.S.Army 1918-1941. p.64
by Peter M.Bowers.

There's also an illustration of in : United States Military AC since 1908. Putnam.

The search for a XP-21 illustration continue's...

You're right, lark. I checked my copy of United States Military AC since 1908. See first attached image.
Second image shows YP-20 from 'Profile 45 - The Curtiss Army Hawks'by Peter M. Bowers.

 

[Stargazer]

Which means we STILL don't have a photo for the XP-21... :-\

 

[lark]

Indeed Sky...

The list of consulted sources is long and distinguished
( to cite an actor in Top Gun but still not the
slightest sign of the subject.

 

[hesham]

My dear Lark,


I will mention a names of rare books,may be you can find it in them;


- American Combat Planes


- Climb to Greatness; the American Aircraft Industry 1920-1960


- Over Land and Sea; Glenn A. Curtiss


- United States Army and Air force Fighters 1916-1961


- United States Military Aircraft since 1909


- U.S. Army Aircraft 1908-1946


- U.S. Fighters - Lloyd S. Jones- Aero Publishers Inc.

 

[Steve Pace]

I found this in my files and as I've marked it I don't know if it's a Curtiss A-3 or XP-21. I wish I could be more help. -SP

 

[Arjen]

Serial number 27-243: O-1B, converted to A-3 , then back to O-1B.
Source: 'Curtiss Aircraft 1907-1947' by Peter M. Bowers, Putnam 1979, p.289

 

[lark]

What I found...

....The two XP-21's were two XP-3A's converted at Wright Field and used as
testbeds for the new 300Hp Pratt & Whitney R-985-1 Twin Wasp Jr.engine....

**And now it comes: Unfortunately for historians,no photo's were taken.

...26-300 became the XP-21 when fitted with a later R-985 and was surveyed on March 7,1931 with 283 hours...

So far Peter M.Bowers in :The Great Fighter Fly-Offs - Curtiss vs. Boeing part II 1927-1933
page 18 - chapter 1930 in :
Wings (Sentry Group) February 2001 Vol 31 No 1.
(I found the mag.on Ebay)

I think with these info , the search for a picture has come to an end...

Only hope for an illustrattion is perhaps that one of the artists on this forum can create a sideview of the XP-21
based on existing fuselage drawings and engine.

 

[Artie Bob]

Perhaps the problem in finding photos of the XP-21 is, if I remember correctly, that much of the photographic archiv material from Wright Field prior to WWII was intentionally destroyed during the 1950s because the negatives were an "obsolete format". I believe that the young AAHS tried to save the material, but the USAF officer responsible for the process was non-cooperative. Much of what still exists came via the 1361st(?) photo squadron, which was the still photo archiv in Washington, DC, a collection which later was moved to the Smithsonian along with the curator, Dana Bell.
So, probably every protoytpe that flew at wright Field during the 20s and 30s was probably pretty well recorded in photo images, it is just that many did not survive.

Best Regards,

Artie Bob