US Navy OS-117 Outline Specification (S-2 Tracker rivals)


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17 July 2006
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I know following projects:

Grumman G-89--------XS2F-1
Vought V-368---------XS2U-1
Lockheed TDN L-192-6
Curtiss-Wright Model ?

And that can tell about other competitors?
Do not forget the Douglas Model 603 and 604.

It was to have had a AN/APS-20 radar in a large ventral radome.
Two 20mm cannons in the nose, and sonoboys and offensive weapons in a forward fuselage bay and externally beaneath the wings.

It was to have been powered by two 1,525 hp Wright R-1820 radial engines.
Span of 15.24 m (50ft) and length of 12.37 m (40ft 7in)

Thats all I have on the Douglas submission sorry

Does anyone have any pictures, drawing and specifications for the Vought V-368---------XS2U-1 ?

I have never heard of the Lockheed TDN L-192-6
Any more info/pics etc on the L-192-6 also?


*Image from Rene Francillon's book McDonnell Douglas Aircraft since 1920: Volume I
Hi Pioneer.

Many thanks for the information.

Come in http: // and there there is a picture of mockup XS2U-1.

More any have no information about XS2U-1.

And the information about L--192-6 will be in two days.
Hi Sentinel Chicken.

Many thanks for image.

If is in book McDonnell Douglas Aircraft since 1920: Volume I the information (figures, 3-view drawings and specifications) about Douglas Model D-? (competitor XF3H-1), Model D-? (competitor YF-102 and XF-103) if it is possible show us.
Lockheed Model L-192-6:

gross take of weight(GTOW):------21800 lb.
maximum speed:------------------------247 knots.
patrol cruise speed:--------------------139 knots.
stall speed:--------------------------------67.5 knots.
minimum endurance:-------------------6.75 hours.
takeoff distance:------------------------300 feet.


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Many thanks for that drawing, Devi :D

What would have been the USN designation for this aircraft it would have been the winer design?....Lockheed SO-1?


Great work Sentinel & Devi finding the 3-view drawing of the Douglas & Lockheed submissions

Know we are getting places with this forum

Ok, comopared to the Devis's and Sentinel's submission this is way easy.. Anyway, this is the Northorp N-60, Northor submission to the comopetion to substitute Grumman Af-2S/-2W Guardian, later originating S2F Tracke. Data: lenght 18.59 m; span 14.66 m; height 5,13 m; wing surface 44,43 sqm.

By the way, to the Tracker competion took part 18 companies with 24 different desings... this is gonna be a loooooooooooooooog topic :D

Uh, source: Docavia's Northrop, what else?


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Hi Skybolt.

Name those eighteen firms with the projects if you can.
Hi skybolt.

If you can, please show us Northrop Model N-31, N-53, N-65, N-94,N-103 and N-132.
( as Northrop Model N-60 )
Eh, eh, N-31 and N-31a were all-wing bomber studies (1948). I'll post but in a new topic, not here (too off-topic). N-53 an interceptor (another topic...). N-65 was another interceptor, but I don't have images. N-94 a Navy fighter (it was tendered for the substituion onf the Cutlass, any idea which competition was?) N-103 another interceptor, don't have anything (I suspect was related to Scorpion). N-132, a strategic fighter (looks like a competitor to the Voodoo). No images. Anyway, in the next few days I'll start topics to cover the images that I have (they all come from Docavia Northrop, by the way...why not buy it ;) ?)

Thanks Devi,

What is your source ?

I suspect AAHS Journal 1999, this smells Bill Slayton a mile away...
Hi Skybolt.

Yes, the brother:

AAHS Journal,1999, Vol.44, Winter(N.4),p.288-297, The Lockheed that never were(part.IV)

I shall wait with the great pleasure on account Northrop.....
The project of firm Martin: Model M-255.

Source of Lockheed TDN Model L-192-6: AAHS Journal,2000, Vol.45, Spring ( N.1 ),
p.53-63, The Lockheed that never were ( pt.V )

I wish to know, when have begun competition.
I wish to know, when have begun competition.
This is easy, Devi:
Navy issued an Invitation to Bid (which is a type of document more generic than an RFP) on January 20th 1950. The contents were: a carrier based airplane with the capability to find, track and destroy a sumbarine without assistance from other aircrafts or from ships; the plane had to be suitable for use from the CVE-105 escort carriers (which was the more stringent specification of all).
Bids came in on April 27th 1950 (fairly fast) and comprised 24 proposals from 14 companies.
The short list eneded up with Douglas (Models D-603 AND D-604), Vought Model 368 (XS2U-1) and Grumman.
As of now we know/have:

Anyone for the other 8 (eight!) companies? Convair? Bell? Ryan? McDonnel? Boeing? North American? Fairchild? Curtiss (still in business in 1950?)?
Many thanks Skybolt.

and what source?

100 % I know, that firm Curtiss-Wright too participated.

Curtiss-Wright Model CW-4? or C-? or P-?
Surce is Grumman Aircraft - Naval Institute/Grumman, in the Tracker chapter. If you have the collection of AAHS Journal, there was an article in 1997 or 1998 on the end of the Aircraft Division of Curtiss and the rejected bid (mainly on the XP-87, by I think other info)
Hi Skybolt.

you, look....It is written about Curtiss-Wright

page:12 (pdf page:14)---"Grumman Wins Competition"
Thanks, Devi! Aside from the stuff on Curtiss-Wright, I was fascinated by the article on the Skyraider with the internal spin-stabilized rocket launcher! As an old Spad-lover with many hours in the right seat as an observer/photographer, this was a total surprise! :eek: Really appreciate your sharing this PDF with us!
Republic NP-52, from Aviation Week 5th December 1958, via Tony Buttler.

Must be a competitor to Type Spec 146, which led to the Lockheed P-3 Orion; 4 manufacturers responded altogether.
Opened fine for me today. That spin-stabilized rocket launcher sure sounds interesting. I thik carrying standarad fin-stabilized rockets makes more sense, though. The launcher sure sounded like a "big brother" to the old Gyrojet pistol.

It was interesting to see that Curtiss was the runner-up to teh S2F. I wonder if that could've kept them in business despite their other ineptness.
Do you have any pics or drawing and specifications for this NP-52 design?

Pic only, which I accidentally forgot to attach :)


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Hay Overscan

Is it just me or does the NP-52 look a little on the small side to be in the race or capability of the Lockheed P-3 Orion, let alone the P-2 Neptune it was to replace - in terms of its size, range capability?

It looks more to me as if it was in the race with the USN's requirement for a carrier-based ASW aircraft, as won by the Grumman S-2 Tracker?

What do you think?

Hi Skybolt

You have told, that 14 firms participated in competition.
What source?

And in the book (Grumman Aircraft Since 1929) 18 firms are told.
Hi Sentinel Chicken

Here the resulted drawing, What from them, Douglas D-603 or D-604?
The two differed by the radar arrangement, AFAIK. There is a picture in Putnam's McDonnel Douglas aircraft vol. 1 of a certain configuration, but not mentioning if it's 603 or 604... :(
Sure! ;D
Alain Pelletier "Les Avions et Engins Northop. Des origines à nos jours", Minidocavia n.21 Editions Larivière 2006, ISBN 2-84890-078-4, 24.00 € in Italy
A much recommended book, by the way.
Sometime they (the topics..) come back..

Boeing Model 490. Same wing and impennage of XF8B, 4-person crew, R-2800. From new and beautiful (and pricey...) "Boeing XF8B Last of the Line" by Jared A. Zichek, Schiffer.


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Thanks for the tip on the book as well as the drawing. I just ordered the book. The XF8B is one of my favs. Since the USAAF tested it as well, any thoughts of what its designation would have been had it entered USAAF/USAF service? Fighter? Attack? I think P-73 or 74, which were unused, or maybe one of the desigantions assigned to an unbuilt design. For attack, maybe in the A-40-something range.

Skybolt said:
Sometime they (the topics..) come back..

Boeing Model 490. Same wing and impennage of XF8B, 4-person crew, R-2800. From new and beautiful (and pricey...) "Boeing XF8B Last of the Line" by Jared A. Zichek, Schiffer.
Hi frank,

but the P-73 was actaully allocated to Hughes D-2.
Looked: no P-XX number assigned to the XF8B. Actually, the test didn't go well, at least for the role the AAF was interested in: long range, high altitude escort fighter. I suppose the competitor was the Twin Mustang.
Skybolt, on the drawing it is not visible specifications. If it is possible, these data show precisely.
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