By
Scott Schwartz
Since the first flight of a Constellation didn’t take place until January 9, 1943, it should
come as no surprise that the United States Army Air Forces (USAAF) was very interested in
this fast, high-flying transport aircraft.
World War Two was well under way, and, after all, the Constellation could out run the
Mitsubishi Zero fighter, in level flight (theoretically, anyway).
Well, the initial plan
was to allow the eighty Constellations
being built for the airlines to be delivered to those airlines, but the
airplanes themselves would actually be owned by the Government. The USAAF would then receive another one
hundred, eighty Constellations (designated
as C-69’s) directly. In reality, the
USAAF decided to take all of the Constellations that were already on the
production line, and it ordered more. A
total of three hundred, thirteen Constellations
were ordered, but only a fraction of these were ever delivered to the Army.
This is because the
Wright R-3350 was turning out to be far from reliable. Many readers will know that the B-29 was
powered by the same engine- and that one of the XB-29 prototypes crashed due to
one of the engines catching fire-killing Boeing test pilot Eddie Allen and the
whole flight crew. Not to mention
fourteen people on the ground. This
didn’t bode well for the Constellation Although the initial test flights of the
XC-69 yielded favorable results (indeed, Boeing’s Eddie Allen was “loaned” to
Lockheed because of his experience with the R-3350 engine and is supposed to
have said that the aircraft worked so well, that he was no longer needed. This was a month before he lost his life in
the XB-29 crash.), all aircraft using the R-3350 were temporarily
grounded.
The trouble was
apparently traced to the design of the R-3350’s carburetor, and flight testing
of the XC-69 was resumed in mid-June of 1943.
Once again, problems-this time in the form of leaking fuel tanks
appeared. This problem was resolved in
April of 1944; but other problems like engine overheating and fires continued
to plague the aircraft. It became so
bad, that Lockheed flat-out accused Wright of poorly designing and building the
R-3350. Lockheed even went so far as to
recommend that the USAAF replace the R-3350 engines with Pratt & Whitney
R-2800’s. In response, the Army simply
insisted that R-3350 production cease until its problems were resolved.
Naturally, this delayed
the testing of the C-69 even further. On
top of this, the C-69 became less relevant to the Army’s needs as the war wound
down. So, most of the successes achieved
with the C-69 were symbolic in nature.
One such instance occurred in 1944, when Howard Hughes flew a C-69 from
Burbank to Washington D.C. The trip was
made in less than seven hours, and the aircraft averaged 346 MPH along the
way. Incidentally, this C-69 was painted
in TWA colors (but, it had a military serial number), and it was to be handed
over to the Army upon its arrival in Washington.
Another aircraft- the
original XC-69 had the distinction of being the last aircraft ever to be flown
by Orville Wright, who was allowed to briefly take the controls during a flight
that had departed from Wright Field.
And, finally, another C-69 was flown from New York to Paris, in August
of 1945. This flight was intended as a
demonstration of the C-69’s trans-continental capability. After all, the C-69 was intended to be a
high-speed trans-continental troop-transport.
Nevertheless, the war had more or less passed the C-69 by, with the Army
opting for the lower-flying, slower Douglas C-54 Skymaster. Further, as the
R-3350’s problems were ironed out, the needs of the B-29 program took
priority. Consequently, only fifteen
C-69’s were ever delivered to the Army. After the war, most of them were sold as
surplus. Eventually, Lockheed converted them into airliners. The old XC-69, which was briefly considered
for conversion to Pratt & Whitney R-2800 power, was sold to the Hughes Tool
Company. Lockheed then bought this
aircraft and converted it into the L-1049 “Super Constellation” prototype.
There is only one
surviving C-69; painted in TWA livery, this aircraft rests at the Pima Air and
Space Museum.
The lackluster success
of the C-69 did not mark the end of the Constellation
U.S. military service, however.
Lockheed introduced the
L-749A version of the aircraft, which was supposed to be a more “economical” Constellation, in 1947. With the ability
to carry 1555 gallons more fuel than the previous versions, the L-749A was
supposed to meet airline requirements for a long-range airliner. During the following year, the
newly-independent United States Air Force (USAF) bought ten L-749A cargo
aircraft, which were to be designated as C-121A’s. The chief differences between the C-121A and
the civilian Model 749A was the former’s reinforced floor and a large cargo
door in the fuselage. C-121A’s were
later used during the Berlin Airlift and as VIP transport aircraft (VC-121’s). Among the most famous of the VC-121’s was an
aircraft that was named “Columbine” (a one-of –a- kind VC-121E)- which was President Dwight D.
Eisenhower’s presidential transport aircraft.
By 1968, though, the C-121A had been completely withdrawn from
service.
But, still, the Constellation lived on in military
service-albeit in a different form.
Back in 1950, the U.S.
Navy had contracted for eleven cargo variants of the Lockheed Model L1049B Super Constellation. And, prior to this, the Navy had ordered
this same airframe as the WV-2- an early AWACS-type aircraft. Well, the new cargo aircraft – first
designated as the R7O and later becoming the R7-1-was actually delivered to the
Navy before the WV-2, because, as a cargo/passenger aircraft, the R7-1 was
easier to build. First flying in 1952,
the R7-1 could be converted from cargo to passenger aircraft relatively
quickly. Typically, the Navy removed at
least some of the passenger seats on long over-water flights, in order to make
room for life-rafts. A couple of R-71’s
were used to re-supply Arctic bases, and one of them is there to this day. It had crashed during a landing attempt in
1970. By 1962, there were fifty R7-1’s
in the Navy’s inventory; during that year, thirty two of them were transferred
to the USAF, which referred to them as C-121G’s. The eighteen aircraft which had stayed with
the Navy were re-designated as C-121J’s.
One of these remained in service as the Blue Angels’ support aircraft
until it was replaced by another Lockheed product- a C-130-in 1971.
For its part, the USAF
had ordered its own version of the Super
Constellation, which it designated as the C-121C. At first glance, the C-121C was similar to
the Navy version. However, there were
some differences. For one thing, the
C-121C had square windows instead of the round ones found on the “J”
model. Further, the C-121C could
accommodate troops (and their gear), passengers, or forty seven
stretchers. And, the seats could be stowed
under the floor, so that cargo could be carried.
Like the civilian
versions, the military variants of the Super
Constellation were powered Wright R-3350 engines that were equipped with
“power recovery turbines”. Also known as
“turbo-compound” engines, the theory behind their operation was simple: the piston engine’s exhaust gases were routed
through a turbine, which turned a drive-shaft that was connected via a fluid
coupling to the engine’s crankshaft. The
idea was that the turbine provided extra power to turn the engine’s
crankshaft. That was the theory. In reality, the system was prone to
failure-so much so, that the set-up was sometimes referred to as a “parts-recovery”
turbine.
Still, the USAF
received its first C-121C’s in 1955, and the type was retired in 1973. One variant of the turbo-compound Super Constellation remained in service
a little longer, though. This was the
EC-121 Warning Star.
The idea of using the Constellation as an airborne radar
aircraft germinated in 1949, when the U.S. Navy took delivery of two Model
L-749 Constellations and had them
fitted with large radomes on top of, and underneath the fuselages. The two aircraft were designated as PO-1W’s,
and their use confirmed the feasibility of operating powerful radar equipment
on aircraft. This paved the way for
development of the next airborne warning variant- the WV-2 (the PO-1W’s were
re-designated as WV-1’s in 1952), which was based on the L-1049 Super Constellation.
To
Be Continued…..
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