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Cosmic
Canberra
Roger
Cook looks at the most unique aircraft to visit the UK in a long while,
the NASA WB-57F at Mildenhall. Pictures by the author, Gary Stedman
and Matthew Clements
To the delight
of many aviation enthusiasts in the UK, the much-anticipated and long-awaited
NASA WB-57F arrived at RAF Mildenhall on the evening of 11 October.
While
in the United Kingdom the aircraft will carry out at least four missions
to collect samples of cosmic dust from the upper atmosphere, flying at
altitudes up to 65,000 feet as part of the Airborne Remote Earth Sensoring
Program (ARES) to build a worldwide database of cosmic dust present in
the atmosphere. Most of the United States has been sampled, but the scientists
are now looking to see if the levels of dust are evenly spread throughout
the atmosphere round the world. The aircraft carries two under-wing pylons,
each with four collectors that are deployed when the aircraft has reached
altitude. The samples collected are sent back to the Johnson Space Centre
at Houston, Texas for analysis. The aircraft has a two-man crew; a pilot
and a systems operator, both of who wear high-altitude pressure suits
when flying on the collecting missions. The pilot station has all the
essential equipment for flying the aircraft with an upgraded glass cockpit
while the sensor operator station contains both navigational equipment
and controls for the operations of the various payloads carried.
 Mildenhall
was selected as the United Kingdom base as it has all of the facilities
to support the NASA missions - the aircraft uses JP-8 fuel and also requires
a supply of liquid oxygen for cooling of the avionics, and Mildenhall
also has a runway of suitable length and with suitable hangarage. To support
the aircraft operations NASA had a motorhome flown in by C-5 Galaxy, which
acts as a mobile office escorting the aircraft to the runway for final
preparations before take off. Each mission takes about four hours preparation
time before the aircraft can get airborne and each mission last between
four and five hours. Cruising at 65,000 feet with a 4,500 pounds payload,
the WB-57 has a range of 2,500 miles.
Registered
as N928NA, NASA 928 was built as a B-57B and entered service with the
USAF serialled 52-1536. It, along with twenty other B-57Bs, was converted
to a WB-57F in 1963 and was re-serialled as 63-13298. The primary user
of the WB-57F was the 58th Weather Reconnaissance Squadron based at Kirtland
AFB in Albuquerque,
New Mexico, and these aircraft were used extensively throughout the world
to sample the upper atmosphere for nuclear debris where there was suspected
atmospheric testing of nuclear devices. Wing spar corrosion cracks were
discovered in the aircraft and it was decided to replace the wing spar
and ribs with a different type of aluminium, but it was not financially
feasible to replace the entire fleet and nine aircraft were put into storage.
Shortly thereafter, the 58th deactivated the remaining aircraft in 1974.
Shortly before
this in 1968, NASA contracted with the United States Air Force to operate
an RB-57F, which flew many missions as part of the Earth Resources Technology
Satellite program. In 1972 the Air Force thought the expense was too high,
and transferred the aircraft to NASA. This aircraft was re-numbered NASA
925 (ex 63-13501) and operated until 1982 when it was retired. This machine
is currently on display at the Pima Air Museum, Tuscon, Arizona.
When the
58th WRS high altitude program was cut in 1974, they also transferred
NASA 926 (ex 63-13503) to Houston. While this aircraft was out of service
for some time due to budget restraints,
it is still flying today, alongside NASA 928, operating out of Ellington
Field in Houston, Texas.
During the
conversion of the aircraft to WB-57F models only the fuselage, landing
gear, and horizontal tail surfaces were kept from the original aircraft.
Although the original Canberra design had excellent high altitude performance
it was significantly improved by addition of greater wing area and extra
engine thrust. Two Pratt and Whitney TF33 turbofans were fitted, each
rated at 18,000 lbs static thrust, almost doubling the power of the original
B-57. The wing was replaced by a completely new three-spar wing, incorporating
honeycomb construction with a marked anhedral, and of almost doubled span
of 122 ft 5 in. The fuselage tank was deleted to allow a pallet system
for the various sensors to be carried, with all fuel now carried in the
wings outboard of the engines.
NASA
928 will remain at Mildenhall until 22 October before returning home to
Texas. With its new wing spars and new avionics upgrade NASA has no plans
to retire 928 and will continue to fly it alongside 926 for the foreseeable
future. Further visits back to the UK are anticipated, so if you missed
it this time, don't despair!
With thanks
to Lt Jamie Humphries, 100th ARW Mildenhall and to all the NASA personnel.
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