Rocket Belt
History:
The
concept of a rocket belt stretches back to science fiction
of the late 1920's comic strip hero "Buck Rogers"
who is supposed to have travelled this way in the far
future. During the same period, an unknown young and foolhardy
German inventor attempted to roller skate more rapidly
than usual by attaching a pack of solid-fuel (gunpowder)
rockets on his back. The all-too brief experiment was
captured in the newsreels of the early 1930's and shows
his embarrassed quick and hard landing on the ground.
Similar rocket-propelled ice skaters tried the stunt with
like results. A rocket belt was also featured in several
movie serials of the late 1940's, notably, "King
of the Rocket Men" (Republic Pictures, 1949).
Technically
speaking, the idea of a workable rocket belt is credited
to Wendell Moore, an engineer with Bell Aerosystems in
1953. Moore then called the device the un-romantic name
of Small Rocket Lift Device, or SRLD. (Ironically, an
earlier concept of a rocket belt was conceived from about
1948 by another engineer named Moore, who was unrelated
to Wendell, and whose first was name was Tom, though his
efforts are less well documented. Some tests were made
by the Army in the early 1950's at Redstone Arsenal but
did not lead anywhere.)
Meanwhile,
Wendell Moore and his colleagues saw this as a great technical
challenge since they had to contend with the problem of
achieving stability of a man using the device. They also
considerable time work out the positions of the small
thrust nozzles for maximum efficiency and safety.
A nitrogen
gas-powered rig was first built and made entirely of steel
tubing. The nozzles pointed downwards and fitted with
small thrust control valves. The device was tethered by
a 15 ft flexible hose to a control system worked on the
ground by a test engineer on the ground operating the
valves which increased or decreased the nitrogen flow.
It was found that the flex hose restrained the users's
movements.
Wendell
Moore himself tried out the first self-operated version
in 1958, though there were ropes attached to control any
unexpected violent manoeuver. The hops were short and
rough but did succeed. In time, arm-control levers and
other refinements were added, but instability was still
encountered in which one of the flying test engineers
was almost injured.
Eventually
a stable flight and height of 15 ft was reached. The U.S,
Army began to show interest in the device by 1959 and
requested a study program. Another aerospace company,
Aerojet-General, was contracted to undertake one of these
studies. Reaction Motors, Inc. (RMI) likewise began experimenting
with similar rocket belts.
The
Army negotiated with Bell for the fabrication of the SRLD
and a contract was awarded to the Army's Transportation,
Research and Engineering Command (TRECOM) for military
feasibility studies and trials. Moore was named Bell's
Technical Director for the project. Under the contract,
a 280-lb thrust rocket motor was made and tested. Peroxide
was chosen as the safest fuel for personnel use as no
combustion took place, just the expulsion of pressurized
peroxide gases, while the operator wore a form-fitting
fiberglass corset for safety. Many tethered flight were
conducted, with Moore as the operator, at the Bell plant
at Buffalo. Jetavators, for controlling the yaw or pitch
were also tried. However, Moore sustained an injury of
a fractured knee in one flight and was never able to experience
a free flight in his invention.
It was
left to another engineer, Harold Graham, to continue the
test flights and to eventually achieve the first free
flight on April 20, 1961. Graham flew successfully at
7 to 10-mph for 13 seconds over a distance of 112 feet.
Other milestones were soon reached, including a flight
over a 30 ft. hill and a flight over a stream and circular
flights over obstacles like trucks. The first public demonstration
was made by the Army at Fort Eustice, Virginia, on June
8, 1961. The flight received wide acclaim and an even
more spectacular flight was made before a large crowd,
including general officers, on the Pentagon lawn.
Public
flights were made thereafter at fairs and similar events
across the country, including a flight before President
Kennedy at Fort Bragg, N.C.
However,
despite the belt's apparent popularity, it turned out
to be a commercial failure, mainly due to its limited
use because of its short duration use. The Army's higher
priority of missile development also contributed toward
the loss of Army interest. The Army, and also Marine Corps
which had considered the belt, did not adopt it and Bell
no longer became sought its further development. In January,
1970, a license to sell and manufacture the Bell Jet Belt
was granted by Bell Aerospace Textron to Williams International
(formerly Williams Research Corp.) of Walled Lake, Michigan.
Williams went onto to develop an improved, longer-duration
jet-powered version of the belt.
Today,
the rocket belt like the original, are occasionally used
for its entertainment and publicity value, at football
half-time shows and in movie stunts. One belt was also
flown at the 1984 Olympic Games.
The rocket belt is not
to be confused with the Manned Maneuvering Unit (MMU)
used by astronauts in space which was a totally different
technological development. The other existing original
Bell rocket belt is found at the State University of New
York, Buffalo campus.
