From: jfb@ihlpl.att.com (Joseph F Baugher)
Newsgroups: sci.military
Subject: Re: In-flight refueling in WWII
Summary: More B-36 variants.
Date: 29 Sep 92 12:59:48 GMT
Organization: AT&T Bell Laboratories -  Naperville, Illinois


From Joseph F Baugher <jfb@ihlpl.att.com>

In article <Buq573.JJF@lawday.DaytonOH.NCR.COM>, pierson@empror.enet.dec.com (dave pierson) writes:
> 
> From pierson@empror.enet.dec.com (dave pierson)
> 
> In article <BuKotn.Aw3@lawday.DaytonOH.NCR.COM>, umteghts@ccu.umanitoba.ca
> (david teghtsoonian) writes...
> 
> >  Thanks to those who responded to my original post. Some interesting
> >technical points were raised:
> >1)Where do you put the refueling booms?  Well mounting the boom on the
> >bomber wouldn't seem to pose a problem. Just stick it on the bottom rear
> >of the fuselage. Unfortunately the turbulence from the prop wash of the 
> >bombers engines would probably be severe enough to make the entire process
> >impractical.
> 	Both B29s and B36s were modified as tankers.  Both are propellor
> 	propelled.  "propwash" didn't seem to bother things.
> 
> [ mod note -- I'd like to see a reference to a B-36 that was converted to a
> KB-36.  Never heard of one.  The B-36 varients I've heard of are --
> 
> 	RB-36 Recon Version
> 	B-36 FICON conversion
> 	B-36 TOM-TOM conversion
> 	B-36 with an on-board nuclear reactor
> 	XC-99 Cargo conversion 
> 
> Steve ]
> 

Here are the experimental versions of the B-36 which I have been able 
to get from various sources.  I'm sure there may be others which I 
have missed.  

The first experimental B-36 was of course the prototype XB-36 
(42-13570).  It flew for the first time on August 8, 1946.  Power was 
provided by six 3000 hp Pratt and Whitney R-4360-25 radials driving 
pusher propellers.  It had extraordinarily-large (110 inch) 
mainwheels.  One of these wheels is on display at the WPAFB museum in 
Dayton, Ohio.  This tire is huge! 

YB-36 (42-13571) was the second prototype.  It had a revised canopy 
with a raised cockpit roof.  It was later redesignated YB-36A when 
fitted with four-wheel bogie main undercarriage units, replacing the 
big main wheels of the XB-36.  

YB-36C was a projected development with R-4360-51 tractor engines 
which went no further than the drawing board.  

YB-36G was the designation given to a swept-wing, pure jet version of 
the basic B-36 design.  Two examples were built and flown as the 
YB-60.  The YB-60 lost out to the Boeing B-52 for production orders.  

GRB-36F was the designation given to RB-36F #49-2707 converted into a 
FICON (Fighter-Conveyor) aircraft.  It was used in tests with a 
Republic YF-84E Thunderjet in 1951.  The Thunderjet would fly up 
underneath the GRB-36F, A cradle would be lowered from the bomb bay of 
the GRB-36F, and the modified Thunderjet would fly up underneath and 
hook onto the cradle.  The Thunderjet would then be lifted up and 
would nestle underneath the B-36.  Tests were made with a swept-wing 
Republic F-84F Thunderstreak in 1952.  

The Tom-Tom trials using the GRB-36F and two RF-84Fs were similar in 
concept.  The fighters had clamps which attached to wingtip hookup 
assemblies on the B-36 so that they could be towed into a combat zone.  
Only a few hookup attempts were made, the wingtip vortices and the 
turbulence ensuring that the operation was a dangerous affair.  After 
one RF-84 was torn loose from the B-36's wing, the experiments were 
terminated.  

GRB-36D was a conversion of the B-36D for the FICON program.  In May 
1953, a contract was issued for ten of these to carry a 
specially-modified RF-84K reconnaissance plane on an H-shaped cradle 
in the bomb bay.  These saw only limited service, and only a year 
later the program was abandoned.  

DB-36H was the designation given to three B-36H bombers modified as 
director aircraft for the Bell GAM-63 Rascal air-to-surface missile.  

NB-36H was the designation given to B-36H #51-5712 when used as a 
flying testbed for an airborne nuclear reactor.  The first flight of 
the NB-36H was on September 17, 1955.  The reactor did not actually 
power the aircraft, and was intended merely to test the effects of 
radiation on the structure, instruments, and equipment of the aircraft 
itself.  These tests were performed in conjunction with the WS-125A 
nuclear-powered bomber project of the late 1950s.  47 flights of the 
NB-36H were made.  The program ended in 1957, and the aircraft was 
finally scrapped in 1958.  A project to built a nuclear-powered B-36 
under the designation X-6 was later abandoned.  

The XC-99 (43-52436) was not a conversion of the B-36, but was rather 
an independent project.  It was a two-deck military transport capable 
of carrying up to 400 troops or up to 100,000 pounds of cargo.  Only 
one was built.  It was withdrawn from use in 1957.  

So far as I am aware, the B-36 was never used as a flying tanker 
aircraft.  

Sources: 

  United States Military Aircraft Since 1909, Gordon Swanborough and 
  Peter M. Bowers, Smithsonian Institution Press, 1989.  

  General Dynamics Aircraft and Their Predecessors, John Wegg, Naval 
  Institute Press, 1990.  

Joe Baugher       AT&T Bell Laboratories    2000 North Naperville Road 
		  Naperville, Illinois 60566-7033.   (708) 713-4548
Newsgroups: sci.military