Aviation Ancestry - August 2012
Seeing Stars- The Military Constellation – Part II
By Scott Schwartz
VC-121E “Columbine III”, which was used by President Eisenhower. Presumably, this photo was taken prior to the complete restoration of the aircraft. (Courtesy of the National Museum of the United States Air Force)Since the first flight of a Constellation didn’t take place until Jan. 9, 1943, it should come as no surprise that the U.S. Army Air Force (USAAF) was very interested in this fast, high-flying transport aircraft. World War II 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 80 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 180 Constellations (designated as C-69s) directly. In reality, the USAAF decided to take all of the Constellations that were already on the production line, and ordered more. A total of 313 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 14 people on the ground. This did not bode well for the Constellation though 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 was 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-2800s. In response, the Army simply insisted that R-3350 production cease until its problems were resolved.
“Columbine III” on display at the National Museum of the United States Air Force. This aircraft was named by the then First Lady for the official flower of her adopted home-state, Colorado.(Courtesy of the National Museum of the United States Air Force) 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-69s 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 1,555 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-121As. 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-121As were later used during the Berlin Airlift and as VIP transport aircraft (VC-121s). Among the most famous of the VC-121s 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 11 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-71s were used to re-supply Arctic bases, and one of them is still there to this day. It had crashed during a landing attempt in 1970. By 1962, there were fifty R7-1s in the Navy’s inventory; during that year, 32 of them were transferred to the USAF, which referred to them as C-121Gs. The 18 aircraft, which had stayed with the Navy were re-designated as C-121Js. 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 47 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-121Cs 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-1Ws, 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-1Ws were re-designated as WV-1s in 1952), which was based on the L-1049 Super Constellation.
To Be Continued…..
