lacy@saturn.UUCP (Sharon Lacy) (09/18/84)
At the risk of contradicting someone who has first hand knowledge, I wanted to add some information that I got from my father. He was in the Air Force from 1950 - 1973 and worked on several of the planes that have been discussed. The B-36 did indeed have a smaller plane "attached" to its belly. The project was known as "Ficon" and the plane was an F84G. The Ficon was retrieved by a hook extending from the belly, a couple of stablizers secured it and the pilot left the Ficon and entered the B-36 via the bombay. The tube was used to connect the pressurized cockpit to the pressurized gunners compartment. You traveled from the cockpit to the gunners compartment by laying on your back on a sliding platform and pulling yourself along with an overhanging rope. He contends that the B-58 had less than a full "life" because it was difficult to maintain. Sharon Lacy hplabs!lacy
tggsu@resonex.UUCP (Tom Gulvin Root) (09/20/84)
You won't believe this, but my B-58 Hustler hand book says that it started life as a new drop plane for the B-36! The weapon/fuel pod would contain engines as well (dropped with the bomb (er, device) - I bet few practice runs would be made each year!). Though fairly detailed, it contains no real info on why it was withdrawn and replaced with the FB-111 (which is nearly as old but still around). BTW, does anyone know if the B-1B roto-tiller is going to replace the (almost forgotten by the media/etc.) FB-111? Tom Gulvin - Resonex, Inc. - Sunnyvale CA.
dsmith@hplabsc.UUCP (David Smith) (09/25/84)
I dug out my July 1976 issue of AIRPOWER, which has its cover article on
the B-58.
Re: B-58 as "drop plane"
"One of the more interesting Convair proposals at this time [1949-51]
was a parasite configuration designed to be carried by a B-36 to within
1,500 miles of its target. Like the actual B-58 finally rolled out
several years later, it was to carry its weapons load externally."
There is a picture of a B-58, less nose, being carried by a B-36. The
caption says
"Structural test equipment at Convair was not sufficient to thoroughly
test an airframe as large as that of the B-58. Accordingly, one was
pulled from the assembly line and temporarily mated to a Convair B-36F.
In March of 1957, this concoction flew non-stop from Fort Worth to
Wright-Patterson AFB, Ohio where the tests could be successfully
conducted. In order for the flight to take place, the two inboard
props of the B-36 had to be removed. The mother ship's landing gear
was left fully extended for the duration of the trip."
The picture makes it clear that the removal of B-36 propellers and B-58
nosecone, and nonretraction of B-36 landing gear, were necessary.
Re: jet-powered weapon pod
"By December of 1951, Convair's MX-1626 had evolved to the point where
it was superficially resembling the airplane that was soon to become
the B-58. By this time there were three crew members, the pod was free
falling and no longer self-propelled (though this possibility, along
with numerous others, was kept as an option) and the nose configuration
had taken on that rakish, distinctly beautiful, B-58 look."
"Numerous pod designs and approaches were submited for use with the
B-58, including the 100-mile range rocket-powered variant shown here...
Submisions covered the gamut of possibilities from reconnaisance
platforms to anti-satellite missiles."
Performance
"B-58 usually lifted off at 190 knots with a rate of climb at sea level
of 17,000 fpm. with a full load. Lightly loaded, this increased to an
incredible 46,000 fpm. with afterburner, which was faster than that of
an F-4 Phantom."
Structure
"One of the more significant advances afforded the B-58's structural
development was the incorporation of honeycomb sandwich as a major part
of its structure. Several types were utilized in the airplane,
including glass fiber, aluminum, and stainless steel core. Roughly 90
percent of the wing surface was honeycomb sandwich and about 80 percent
of the total airframe. The material itself offered a stiff, light
structure resistant to aerodynamic and sonic fatigue and easily
conformable to the critical tolerances necessitated by supersonic
flight.
"B-58 structural weight was kept at an absolute minimum. In fact, this
became one of the more successful [maybe too successful; see below
--drs] aspects of the development program, eventually resulting in a
dry airframe weight that amounted to only 14 percent of the total
weight of the airplane."
Strength, accidents
"Though losses were inordinately high, the test program continued
throughout 1957 and 1958. Accident causes varied, but some of those
that eventually came to light included loss of the vertical stabilizer
at high Mach due to assymetric yaw (usually attributed to the loss of
an engine), freezing of elevon ratio changers, malfunctioning of the
computerized fuel transfer system for maintenance of center of gravity,
and general structural failure due to over-control (under the most
ideal of circumstances the B-58 could not be subjected to more than +3
gs or less than -2 gs). Additionally, at least one accident occurred
when overheated tires exploded in the landing gear wells rupturing
hydraulic and fuel lines, and totally incapacitating the airplane."
"Very early in the flight test program, [Beryl] Erickson [Convair's
chief of B-58 flight test] had predicted a high loss rate due to
accidents. Unfortunately, his prediction was to prove all too
accurate. Of the first 13 airplanes, three were lost in fatal
accidents. Of the second lot of 17, no less than six were lost. Fully
one-third of the total test batch of 30 were destroyed before the B-58
test program ended."
"The B-58's safety record, later to become an overwhelming factor in
its removal from service, was nothing to write home to momma about.
Fully 20 percent of all B-58s built were eventually destroyed in
accidents, not a few of these occuring during the course of its service
career. A sophisticated airplane, it depended to a great extent on the
abilities of its electronic wizardry, the knowhow of its mechanics, and
the skill of its pilot to keep it in the air. Mistakes were forbidden
and it was rare that one got the chance to make another."
Gone, but why?
"Now that the B-58's days have come and gone, the nagging question
remains, why did it have to go -- and why weren't more B-58s built to
begin with?
"Many reasons have been presented, but only a few are valid. In truth,
the demise of the world's first supersonic bomber can be directly
traced to two things; (1) it was an extremely dangerous airplane to
fly, and (2) it was not configured for low-altitude weapons delivery
technique.
"The B-58's safety record was miserable. The fatality rate was the
highest in the Air Force. Some crews (and these were hand picked) when
questioned confidentially, admitted to being afraid of the airplane.
Their discouraging words were not long in reaching the ears of the 'big
boys' in the Pentagon.
"During the years of B-58 development, much thought had been given to
the airplane's capabilities at low altitude. In the years to follow,
the B-58's low-altitude flight characteristics were to prove exemplary.
However, at low altitudes, the airplane's fatigue life was shortened
considerably. It had been designed for high-altitude, high-speed enemy
territory penetration, at a time when a low altitude capability, flying
under enemy radar, had seemed of secondary importance. Now, despite
its obvious merits, it could not be utilized for what was, in effect, a
totally different mission.
"In the meantime, Russia's anti-aircraft defenses were known to be
improving almost by the hour. Loss of Gary Powers' U-2, most likely to
an anti-aircraft missile, in 1960, underlined this fact in red ink.
The writing was on the wall -- high altitude penetration was out, low
altitude penetration was in. Even so, the B-58, not readily applicable
to the low altitude job, was allowed to stick around for a while. But
by 1969 it was no longer considered a viable delivery system.