Curtiss XP-55 Ascender canard fighter (Model CW-24)

[Stargazer]

OK, I realize that I'm coming into this discussion way late, but I've always loved the look of the XP-55. My question is what lead Curtiss to go with swept wings? As far as I know, few if any American engineers knew of the benefits of swept wings (as far as trans-sonic speed is concerned). Was it to help move the CG back?

I still plan on building my own XP-55 rubber powered free flight model some day. Need to vastly improve my building skills first.

Although swept wing associated with jet engines came late during the war and originated in Germany, there were quite a few types and projects featuring wing sweep before that, notably in association with canards (but not only): think of the Miles Libellula, the Waterman Arrowbile and even long before that, some of Dunne's pre-WWI biplanes (see U.S. Army Air Service's very first war plane below).

 

[Jemiba]

I think, we have to distinguish between wing sweep applied purely because of keeping
the CG within limits, an wing sweep for solving aerodynamical problems at higher speeds.

 

[Retrofit]

For the tailless aircraft like the Waterman and Dunne's ones, swept wing are used along geometrical or aerodynamical twist to maintain longitudinal stability.

 

[Wahubna]

As ninjrk can attest, the AirZoo has some fantastic documents covering the flight test program and the accident report for the one that ended up on its back.

ninjrk, I used to volunteer there while going to WMU for my aero engineering degree! Greg Ward was kind enough to share the scans they made of the documents.

There was some real funky issues with the bird. Its stall was horrendous which is how one ended up on its back. It actually flipped over backwards in the stall if I remember the report details right.

I was told the AirZoo's never flew...is that wrong ninjrk?

 

[Vladimir]

Goblin engine

Please, more info about it

 

[ninjrk]

If I remember correctly you're correct, it never flew. I know if didn't have an engine when the Zoo got it. I was able to take pictures of it over the course of it's restoration; if you'd like a bit over 600 photos I put them up here: http://smg.photobucket.com/user/ninjrk/library/XP-55

 

[Jos Heyman]

I assume the latest items in this discussion refer to 42-78846. That one flew, see attached photo from 1000 aircraft website.

 

[pacopepe]

additional info-post-3

Fantastic project the last one. It´s one of my favourites.

 

[XP67_Moonbat]

Is that from Fantastic Plastic?

 

[pacopepe]

Is that from Fantastic Plastic?

It cames from the XP-55 kit on 1/72 of MPM; with the cockpit of a P-47; and a high work of scratch. The scheme is similar to Justo Miranda´s drawing on Reichdreams, Unknown! No. 5.

Regards
FRan

 

[Justo Miranda]

Hi

 

[XP67_Moonbat]

You're awesome, Justo! Gracias! :-D

 

[Steve Pace]

Thank You, Justo!

 

[Pelayo]

Gracias pacopepe; you´re AWESOME too!

 

[Justo Miranda]

 

[ACResearcher]

Who was the author of the AAHS article upon which your drawings are based?

AlanG

 

[overscan (PaulMM)]

Please, Justo, post your scanned material sources as requested many times before.

 

[Justo Miranda]

Who was the author of the AAHS article upon which your drawings are based?

AlanG

I am afraid I cannot give you any name. I just keep a photocopy of the page in my files that I included in post USN309

 

[Justo Miranda]

Please, Justo, post your scanned material sources as requested many times before.

Of course

 

[overscan (PaulMM)]

Author?

 

[Apteryx]

Author of the XP-55 article (second of two parts) was Gerald H. Balzer. The two-part article was the third of four articles on unconventional US fighters related to R40-C.

 

[ACResearcher]

Thank you, Apteryx. I thought that read like Gerry's work. He is an excellent researcher and writer. He greatly expanded the information in his articles into a great book covering the X-54, XP-55 and XP-56. Well worth picking up.

AlanG

 

[Apteryx]

Good to know! I'd seen the book listed, but assumed that, given the extensive treatment in the articles, the book would be, if not the same material, a "condensed" version. Thanks.

 

[GeorgeA]

Somehow I missed it when it first appeared, but just bought it recently. I heartily recommend it. It also has a brief but well-done overview on the Hyper program.

 

[blackkite]

Hi!
You already know what I want to say.
You can see radiator cowl flap and cooling fan in these pictures.
http://wiki.warthunder.com/index.php?title=XP-55_Ascender
"The ХР-55 prototype (Ser No. 42-78845) performed its first flight on July 19, 1943, at Scott Field Air Force Base, not far from the Curtiss-Wright factory in St. Louis. The tests showed that the ХР-55 had satisfactory controllability when flying horizontally or gaining altitude, but the pilots experienced some inconveniences when landing or flying at low speeds, as they could not feel any load on the elevator. There were also some cooling problems with the Allison V-1710-95 engine, which was located in the rear section of the airframe."
https://www.youtube.com/watch?v=ybEDawKLvjE

 

[XP67_Moonbat]

Any chance that Justo could re-post the Jet Ascender stuff he HAD posted here very recently?

 

[Boxman]

Here's some nice ground and ground-to-air newsreel footage of the Curtiss XP-55 Ascender (USAAF Ser. No. 42-78846) posted on YouTube by Buyout Footage Historic HD Film Archive.

Strangely enough, the most "startling" portion of the footage to me was the range of travel of the all-moving elevator.

 

[Motocar]

I have a cutaway of the XP-55 jet retouched from one published here, can I share it on the topic ...? Here I leave the link where I publish it in the themes "User Artwork":

http://www.secretprojects.co.uk/forum/index.php/topic,23005.msg307194.html#new

 

[hesham]

From Le Fana 224,

the early study for XP-55.

 

[Stargazer]

Le Fana simply reused these images from the AAHS article by Gerald H. Balzer (Part 3A, Summer 1996).
This particular part of the article had 24 pages, no less! Absolute must read for anyone interested in that program.
The article also contained two full general arrangement views of the CW-24B, both in its early and final configurations, which I'm reproducing here in a smaller size.

 

[sienar]

Le Fana simply reused these images from the AAHS article by Gerald H. Balzer (Part 3A, Summer 1996).
This particular part of the article had 24 pages, no less! Absolute must read for anyone interested in that program.
The article also contained two full general arrangement views of the CW-24B, both in its early and final configurations, which I'm reproducing here in a smaller size.

American Secret Pusher Fighters by the same author has the drawings too, and probably easier to come by.

 

[Stargazer]

American Secret Pusher Fighters by the same author has the drawings too, and probably easier to come by.

But the Fana article is quite an old one (July 1988, I think). At that time, there were no "Secret this" or "Secret that" books on the market, since except for the Third Reich Luftwaffe ones, which have always fascinated people somehow, virtually no-one would have spent a penny on a book dedicated solely to projects!

 

[riggerrob]

Here's some nice ground and ground-to-air newsreel footage of the Curtiss XP-55 Ascender (USAAF Ser. No. 42-78846) posted on YouTube by Buyout Footage Historic HD Film Archive.

Strangely enough, the most "startling" portion of the footage to me was the range of travel of the all-moving elevator.
http://www.youtube.com/watch?v=dQ-NQrtqoX0

————————————————————————————

That large range (canard control surface) reminds us of the (current production) Eurofighter Typhoon. That extra up travel helps two ways after landing. First, it forces the nosewheel onto the runway, improving directional control. Secondly, steeply raised canards work as air brakes after landing.

My general impression is that Curtiss Ascendef was primarily a flying wing with a small trimming surface on the nose. Many designers have experimented with this configuration, it few have succeeded. This contrasts with Burt Rutan’s - late 20th century - canards where the canard provides a significant amount of lift.

 

[sienar]

My general impression is that Curtiss Ascendef was primarily a flying wing with a small trimming surface on the nose. Many designers have experimented with this configuration, it few have succeeded. This contrasts with Burt Rutan’s - late 20th century - canards where the canard provides a significant amount of lift.

That is the case.

Also they expected the aircraft to have a higher critical mach than a normal configuration but this was believed to be because of the lack of a normal tail. Its possible that some of the observed wind tunnel results were due to the wing sweep and this simply wasnt recognized at the time.

 

[rinkol]

There was a widely held idea in the 1940s that a conventional tail would limit the achievable mach number. and that the elimination of tail surfaces would be advantageous for transonic flight. The good performance (for the time) of the Me 163 provided at least superficial support for this assessment. There were various attempts to implement this idea, such as the X-4, F7U and DH 108, but the aerodynamics of such aircraft were not well understood at the time and the results were mostly unsatisfactory.

I suspect that the wind tunnel investigations of aircraft such as the XP-55 and XP-56 provided optimistic results, though there is the possibility that adverse results may have been discounted.

 

[hesham]

Hi,

https://crgis.ndc.nasa.gov/crgis/images/4/41/FFT-TestLog.pdf

 

[ninjrk]

For people who like photos. . .

http://smg.photobucket.com/user/ninjrk/library/XP-55

 

[elmayerle]

I suspect that the wind tunnel investigations of aircraft such as the XP-55 and XP-56 provided optimistic results, though there is the possibility that adverse results may have been discounted.

I examined the wind tunnel data from the XP-55 for my graduate stability and control course. As I remember, the stability derivatives were rather adverse.

 

[GeorgeA]

I examined the wind tunnel data from the XP-55 for my graduate stability and control course. As I remember, the stability derivatives were rather adverse.

It seems the more you read about the flying characteristics of a number of those unconventional configurations of the era, the more you realize how much was still to be learned about aerodynamics and control, and perhaps more importantly, the divergences between model testing and actual flying articles. They were challenging aircraft to fly.

 

[blackkite]

Hi!

Curtis XP 55 Ascender

Moin, habe beim Rumstöbern ein interessantes Modell gefunden. Eine Curtis XP 55 Video: http://www.youtube.com/watch?v=4MEmHDvK9Sk# Wikipedia: http://en.wikipedia.org/wiki/XP-55_Ascender Irgendwo hatte ich in Ungarn auch mal einen Bauplan gefunden. Leider gibt es die Seite nicht mehr. Fragen...

www.rc-network.de

Curtiss-Wright XP-55 Ascender

The Curtiss-Wright XP-55 Ascender (company designation CW-24) was a 1940s United States prototype fighter aircraft built by Curtiss-Wright. Along with the XP-54 and XP-56, it resulted from United States Army Air Corps proposal R-40C issued on 27 November 1939 for aircraft with improved...

military.wikia.org