Kelly Page 11
It was the forerunner of the P-80, later redesignated F-80, and its successor T-33 two-place trainer, and the derivative F-94 in A, B, and C versions. When the Air Corps ordered the plane into production, more than 6,000 were built in all. It became this country’s first tactical jet fighter. Robert Gross named it the “Shooting Star” in the Lockheed tradition of naming aircraft after stellar bodies.
Development was not without problems, of course. It was a complete new world of flying and testing.
The first problem we encountered had to do with compressibility again. But it was not the same as with the P-38. Here it came in shock waves jumping back and forth across the hingeline of the wing and aileron. Shock pressure changes would drive the ailerons and make them “buzz” at a very high frequency. We had known that we would encounter compressibility in some aspect with the airplane, and it was experienced at speeds of Mach .8 to .85. The pilot would get some warning. He would experience a little control stick shaking and feel the aileron “buzz” in the cockpit.
This effect we were able to overcome with hydraulic dampers acting as shock absorbers located on the aileron and attached firmly with no slop, or freedom, of movement.
Again, we used wind tunnels to find out what degree of safety we had. We fluttered a full-scale F-80 wing for more than 100 hours until it finally tore loose at the hinges and the ailerons flew down the tunnel. The NACA flew the airplane and exceeded that mark by flying to Mach .86. My hat is off to that pilot, because the test really made a shambles of the ailerons. But this top speed never became a limiting factor since the plane had more than enough speed for the competition.
A problem developed with the new engine. Test pilot Tony LeVier was flying F-80 No. 3 on a high-speed run at altitudes of 15,000 to 20,000 feet when suddenly there was a booming sound so loud that we could hear it on the ground. As we looked up, the airplane disintegrated and a parachute blossomed.
As Tony explained, “I was sitting there all fat and happy, when the airplane suddenly flipped over on its back, the wings broke off, and I was sitting out in space.” He had to release the cockpit canopy, of course, to get out. It took Tony about ten minutes of excited recollection to tell us this story once he had landed.
But a local farmer who had witnessed the same thing from the ground put it this way in less than ten seconds: “I looked up, there was a boom, and then a parachute.”
When we had collected all the aircraft and engine pieces. we found that the jet turbine disc had broken into three parts, slicing through the fuselage. The reason for the failure is a problem to this day. We do not have in this country a machine big enough to forge these large metal aircraft parts; they must be welded—and that always presents a possible failure point. The largest machines we have are the few we captured from the Germans after the war.
On the F-80, the engine had a weld in the main shaft that came off the big turbine disc, because the biggest press in the country at that time could not forge it—hub and disc—together. Six F-80s were lost for that reason.
We changed the design of the hub as much as we could, then spun each turbine with its shaft in a vacuum to speeds faster than operational. That always worried me—it seemed somewhat like seeing how far you could hang out a window of a ten-story building. The test procedure itself could have started a crack, which might then have been missed in X-ray, and the plane flown with this fault. However, this did not happen and the solution worked.
With the F-80, the Air Corps was able to develop tactics for flying against the German jets—both with bombers in defense and fighters in attack, not only with single aircraft but in formation. We spent several weeks flying with the military at Edwards. All the various U.S. fighters were there—P-38s, P-39s, P-47s, and P-51s—to be evaluated against the jet as escorts for our bombers. They were armed with gun cameras to record their “kills.” So were the B-17s and B-24s.
I spent more than five hours each day, at 25,000 feet—wearing tennis shoes, shorts, and a parachute—riding “piggyback” in a modified P-38 with Tony LeVier, watching them try to gun down the jet. We got into some very fancy maneuvers; all of us spun in trying to turn into the F-80. I must confess I enjoyed it; the P-38 was a good airplane for spins, easy to pull out.
“I got him! I got him!” the gunners would exclaim. But back on the ground, their film never showed a hit on the F-80.
The F-80 would make head-on passes at the bomber formation, roll over, and pass underneath inverted. Lateral and tail attacks were practiced. The fighters were flying defense. The air was crowded with airplanes.
These mock flights were very valuable. We discovered that while it was impossible to stop a frontal attack by the jet, it didn’t matter much. At a closing speed of more than 700 miles an hour the probability of an Me-262 pilot’s scoring a hit in the few seconds’ firing time he had while avoiding collision with the bombers and fighters was so remote that we decided not to worry about it. The main concern turned out to be attack from the rear quadrant, where the German jets could overtake our aircraft, fly at any matching speed, and have considerably more time to aim and fire. To counter this, the Air Corps developed the tactic of having the fighters watch the rear. These exercises with the F-80 saved the Eighth Air Force from having to discover in combat that characteristic of the German jet fighter.
One night test that provided valuable information also resulted in a tragic loss. An F-80 took off with a B-25 as observer to determine whether the jet left a telltale glowing exhaust trail. It didn’t, and the two planes collided in the darkness. Lockheed test pilot Ernie Claypool and the military pilot were killed.
Before World War II ended, four F-80s were sent to the European theater. They were there for indoctrination flights only, on patrol from England and Italy. We didn’t want them shot down where the Germans might capture them. The Air Corps needed familiarity with the airplane, with its high fuel consumption, high speed, and operating characteristics in varying weather conditions. We lost one of these planes and its pilot. Very skilled and experienced, Maj. Frank Barsodi completing a high-speed, low-altitude pass apparently decided he was going too fast for a landing and pulled back on the engine throttle in flight. The result was more pressure from ram air on the outside of the tailpipe than from within, and the tailpipe collapsed inward. At least, that is what I think happened. This was an unforeseen occurrence because its pipe had been designed to withstand inside pressure. The modification here was to vent the pipe so never again could the pressure become higher on the outside than inside.
Development of the F-80 was to cost yet another life—that of our long-time Lockheed test pilot Milo Burcham. In the first production model, as distinguished from the experimental models trucked to Edwards for flight test, Burcham took off from the east-west runway at what then was Lockheed Air Terminal, now Burbank-Glendale-Pasadena Airport. In those days there was a lot of open space where a pilot could pancake in if necessary. But there also was an open gravel pit near the runway. Barely off the ground at 200 feet, Milo lost all power. The drive to the fuel pump shaft had sheared the spline. He couldn’t avoid the gravel pit, and the plane exploded on impact. The design result was an improved spline and pump and installation of an emergency fuel system.
Ever since then, Lockheed aircraft always have had standby fuel systems, either double fuel pumps on the engine or a fuel pump on the engine and another with electric drive. Some other jets do not have this. Redundancy in systems since then became a mania with me. With everything we build, we make sure that we can relight, restart, and keep flying if the main engine pump fails. Milo’s death contributed to future safety for others.
The war in Europe ended before the F-80 could be proved in combat there. But development, testing, and production continued.
When the Air Corps team went to Germany after the war to inspect military capabilities, we at Lockheed were invited. I stayed home to work on the F-80 development, but my assistant, Ward Beman, made the trip and picked up a great deal of informa
tion.
We found that the Germans had been flying the only axial flow jet engine in the world, fundamentally more efficient than the centrifugal compressors of the British jets because it was of simpler design. The flow went straight into the inlet and progressed in a straight line through the engine and out the exhaust. In centrifugal flow, the air goes in two sides of a rotor, flows perpendicular to the flight path of the airplane, enters the burner cans, then goes through the rest of the machine; so that it changes flow 90 degrees at least twice. But we and the British had a great deal of experience and knowledge of centrifugal compressors from use with steam power plants so that had seemed a surer and safer development.
Postwar, the Air Corps dramatically demonstrated the capability of its new air-defense weapon. In January 1946, three F-80s departed the West Coast on the same day for cross-country flight—two with a refueling stop, one nonstop.
Col. William Councill took his F-80 from Long Beach to La Guardia Airport in New York in the record time of 4 hours, 13 minutes, covering the 2,470 miles at an average 584 miles an hour. The feat was widely heralded in the nation’s press. Councill’s plane had carried 300-gallon wingtip fuel tanks dropped over Kansas farmland when empty. We heard later that the tanks were cut in half by farmers and used as feed bins. Refueling stops—at Topeka, Kan.—for the other two planes were completed in just a few minutes, so there was very little difference between the one-stop and non-stop flight times.
There was an amusing aspect to the record-setting takeoff. The official FAA timer came over to our chief flight test engineer, Rudy Thoren, pulled out a dollar watch, and asked Thoren the time! Of course, the quality of his watch didn’t really matter. All he had to do was establish the starting time in any manner. Someone at the finish would record landing time. But the official image suffered somewhat.
More records fell. In 1947 when the Air Force became a separate service, Col. Albert Boyd averaged 623.8 miles per hour over a measured course for a world speed record. Incidentally, jet fuel in those days, more like kerosene than gasoline, cost about 13 cents per gallon, not the $1.50 it costs today in the ’80s.
Congratulating Tony LeVier following a successful test flight during development of the F-80, the nation’s first tactical jet fighter. Below, even by today’s standards the Shooting Star looks sleek and swift in this earlier photo.
The F-80 had proved so easy to handle that it took an effort to interest the Air Force in a training version. We made a piggyback version first—that is, with an enlarged cockpit so an observer could ride behind the pilot. Then we took a plane off the production line—had it disappear from the books temporarily—and converted it to a two-man model for demonstration purposes to convince the military of the need for a two-place version. Once convinced, the Air Force bought thousands of them, as the T-33. The Navy bought a trainer version, too, the TV-1.
Sometimes it’s awfully difficult to convince the customer of what we think he needs, and sometimes we don’t succeed. One such proposal was our Universal Flight Trainer.
In 1954 we suggested equipping the T-33 with “black boxes” to simulate performance of any other kind of aircraft—long before we had such flight simulators in the laboratory. But I could not sell the idea. Airplanes have been used in this manner since—both the JetStar and the F-104 Starfighter have been instrumented to simulate various phases of Space Shuttle performance, for example.
The current “new generation trainer,” I believe, will have some of this capability. Such a “universal trainer” still would be practical and productive in research and development.
The F-80s in the Air Force were able to prove themselves in combat when North Korea invaded South Korea in 1950. In history’s first jet battle, an F-80 shot down a Russian-built MiG-15. And that dual fuel pump that resulted from Milo’s death brought a lot of pilots home from combat in the war zone. Jet combat in that theater provided other lessons we would use in aircraft development. We knew we had enough to keep us busy for some time.
12
Lessons from Korea
WHEN TEST PILOT TONY LEVIER FIRST SAW the F-104 Star-fighter, he asked, “Where are the wings?”
It is true that the wings were short, straight, and almost razor thin, but they carried quite a load. They were the result of tests on some 50 wing models fired on instrumented rockets attaining speeds of 1,500 miles an hour.
The “Missile With a Man in It” resulted from my tour of the Korean battlefields in 1952. Lt. Gen. Benjamin Chidlaw, chief of Materiel Command, and other Air Force officers wanted to discover—and wanted the aircraft designers to know—how our aircraft were performing and what our combat pilots needed in confrontation with the enemy. This was the first war in which both sides had jet aircraft. The North Koreans—in effect, Chinese—had the MiG-15. The South Koreans—in effect, USA—had the F-80, F-84, and later the F-86.
It was an education to see our pilots operating from forward bases like Taigu, their aircraft so heavily laden on takeoff with wingtip fuel tanks to fly into enemy territory that the tanks would scrape the runway. The runway was made of steel planking and there was danger of fire, but they did it day after day.
We interviewed these pilots as they climbed out of their aircraft on return from missions. What did they want in a fighter? It was unanimous. They wanted speed and altitude. In combat at fighting altitude the two sides were about equal in speed. We were much more maneuverable with power controls, and our pilots had the advantage of the latest gunsights. Overall, our margin of victory was something like ten to one.
But our pilots were insulted constantly by “High-altitude Charlie,” sitting at 50,000 feet and directing the MiGs in Chinese or Russian.
“Don’t worry about the American airplanes. Your airplane will take care of you. Just come up here. They can’t get up to you,” our pilots heard constantly.
On our tour of the Korean battlefronts, we covered more than 23,000 miles and visited 15 air bases, flying in an Air Force Constellation.
On night flights, my civilian companion, Lee Atwood, vice president of engineering for North American Aviation, and I slept on a piece of plywood placed on the floor. I could detect vibrations from number three engine coming through a rear spar. The engine ran rougher and rougher but held together as we flew to Hawaii, then Wake, up to Japan, around the Korean air bases, down to Okinawa, and on to Manila. Just as we attained cruising altitude on takeoff from Manila, there was a big bang and number three was dead. We dumped fuel and returned. The Air Force had carried enough spare parts for a minor overhaul, so within 12 hours we were on our way again.
When we returned to the U.S., I set out to design a jet fighter that would fly higher and faster than anything flying anywhere. There was no formal requirement from the Air Force yet for such a plane, but that was cleared up very quickly with a visit to the Pentagon. When I showed my proposal to Gen. Don Putt and Don Yates and Col. Bruce Holloway, they were very receptive. The only obstacle to a contract was the absence of a document specifying what the next fighter should be.
“Well, if there isn’t a requirement, I’m going to make one,” Colonel Holloway decided. “Stick around, Kelly. Come back in a couple of hours.”
He then wrote a page and a quarter on what the Air Force required for its next fighting plane. It should be lightweight, capable of certain performance at sea level and high altitude, and carry specific armament, radio, and other instrumentation. In that short span, he had obtained the approval of all the appropriate generals.
“Here are your requirements,” he told me. Generals Putt and Yates agreed. “Go see what you can do with this.”
The result was the F-104 Starfighter, which would become the SuperStarfighter, and evolve through eight different models and production in the U.S. and six other countries of the Free World over a period of more than 25 years. This was to be the largest international industrial collaboration in the world. The airplane eventually would be flown by 14 allied air forces as well as the USAF. A tw
o-place version also was built, not only for training but for tactical use.
The F-104 became the first operational airplane to fly twice the speed of sound in level flight.
Development of those short, thin wings utilized a new test technique—out of necessity. We didn’t have a wind tunnel capable of going to Mach 2, the speed for which we were designing the airplane, so I visited Lt. Gen. Earle E. “Pat” Partridge, in charge of the Air Research and Development Command in Baltimore, and described the problems we were having in testing the thin wing as well as the tail and air intake ducts for the new fighter.
“What can I do for you?” he asked.
“Well, if we had a bunch of five-inch rockets, we could put the wing models on the rockets. If we shot enough of them we could find out how to make a wing with the thickness we want—about twice that of a razor blade. We can see if it flutters or not in supersonic flight.”
Immediately, General Partridge sent a message to Korea, “Stop shooting rockets for one morning and send them all to Kelly.”
Two weeks later when I returned to Burbank, the Skunk Works was in an uproar. There were about 460 rockets on hand and no one knew what to do with them. It wasn’t a good idea to store them in the middle of Burbank, and, of course, we couldn’t fire them from the city. We moved them all to Edwards Air Force Base, where there was plenty of open country within the security of the test base boundaries.
We fitted the rockets with automatic cameras and telemetering equipment to radio data to ground observation stations. We put wing after wing on instrumented rockets and fired them from the desert base. Wings with different stiffness, different shapes, different designs, at speeds up to 1,500 miles an hour. There had been some question within the industry about the advisability of making a wing as thin as we proposed. Not only did the final design prove solid in test flight and in service, but we later hung wing tip fuel tanks on it, a great deal of armament, and even added A-bomb carrying capability.