Read Roaring Thunder: A Novel of the Jet Age Online
Authors: Walter J. Boyne
January 10, 1948, Inglewood, California
The only reason Vance hated to work on Saturdays was because it distressed Madeline, who liked him to be at home, doing the endless puttering required of their new house in the Malaga Cove section of Palos Verdes. She was amazingly inconsistent, behaving exactly like a wife in every way but the second-most fundamental: she would not get married. She stoutly refused to have her name on the mortgage papers, as if it were some sort of American stigma to be formally designated as a home owner. Vance had long since given up trying to understand her, knowing that he was lucky to have her and hoping to hold on to her for a few years more.
Normally he wouldn’t have gone in, but the problems with the North American XP-86 were severe and the first two orders for P-86As were due to start being delivered to the eager young pilots in the Air Force during the summer. The biggest trouble was the General Electric J47 engine, which was not putting out its required thrust and was failing at faster intervals than specified. Then
the three-thousand-pound-per-square-inch hydraulic system was giving trouble—the nose gear would just fold up on the ramp without any warning, and there were also problems with the aileron system. Vance knew he was getting old because he distrusted a powered aileron instinctively, even as a backup, although intellectually he knew it was the only solution at jet aircraft speeds.
He had done his bit for the XP-86 three years before, sending word from Germany to use a thirty-five-degree swept wing. North American had acted on his input and changed the fairly sedate straight wing design they were working on into a tiger of an airplane. Then he had kept his hand in from time to time on special projects after its first flight on October 1, 1947, with George “Wheaties” Welch at the controls.
Welch, who had gotten a Curtiss P-40 off the ground when the Japanese attacked Pearl Harbor, was rumored to have taken the XP-86 supersonic soon after the first flight. The story was that the Air Force suppressed the news because it wanted the honor of breaking the sound barrier to go to its expensive new experimental rocket plane, the Bell XS-1. Chuck Yeager had duly exceeded Mach 1 on October 14, and although the flight was classified, industry insiders were aware of it. Welch, a good and trusted friend, never told Shannon personally that he broke the sound barrier, so Shannon was inclined to discount the rumors.
Now Dutch Kindelberger, North American’s president, impatient with the progress at General Electric, had tasked him and a special so-called tiger team to come up with a solution to the engine problems. He excused himself with the task of increasing the thrust—he felt this would be solved with the later version of the engine that was due off the production line shortly. But he did think he could help with the reliability problem. To him an engine was an engine and it didn’t matter whether there were pistons or turbine wheels; they all rotated and they
all depended upon adequate lubrication. He was convinced that somewhere in the GE engine’s system there was a weak link in the lubrication that was causing the early shutdowns. Then, too, he hated the fact that electronics had become such an integral part of engine design. He didn’t mind the old-fashioned temperature gauges, but now the engine thermocouples, whose purpose was to sense heat and register its degree on an instrument, were exposed to such extreme heat that they were almost certain to malfunction.
The difficulty was that post-shutdown analysis reports were all over the waterfront, with blame being pinned on everything from turbine blade design to the shape of the engine inlet. He realized that it could be construed as arrogance on his part to believe that he could compete with General Electric, with all its tremendous talent, but he felt he knew intuitively where the problem must lie.
The huge North American hangar was almost vacant except for a company B-25, used as an executive transport, and a visiting Lockheed P-80 from Edwards Air Force Base. In the center of the hangar, a J47 engine was suspended on a carriage, and two GE engineers, Walter Baker and Steve Shaddock, were on hand to help him. On a table, bathed in the blaze of the hangar’s overhead lights, were stacks of drawings and manuals.
Vance knew both engineers from the days when he had helped bring Whittle’s prototype over and felt that they were comfortable with him, even though the meeting was an implicit criticism of General Electric. It was important not to appear to be one of the infamous “experts from out of town” who soured so many industry relationships.
“Well, boys, let’s begin tearing this beauty down.”
The three men worked silently together, carefully disassembling the engine, with Vance’s eyes searching each part as it was removed.
Four careful hours later, the J47 parts were laid out on the hangar floor in the same relative position in which
they were mounted in the engine. Vance walked among the parts, stopping occasionally to stare, to scratch his head, to pick up a piece, examine it closely, then move on. After an hour he called, “Walter, Steve—come take a look at this.”
They looked at a short length of stainless-steel tubing, about three-eighths of an inch in diameter. “Vance, that’s the oil supply line. What about it?”
“I say it’s too large in diameter. At high altitudes, with the temperatures up, the oil is almost certainly foaming, at least a little, and this line probably doesn’t allow enough oil to get through to lube the bearings.”
Both men shook their heads. “That’s hardly likely, Vance. Jet engines don’t use oil like a piston engine does; you can run them practically dry of oil and they’ll keep on turning.”
“I’m sure you are right. But I feel in my bones that when the oil foams, it blocks the line, and the bearing temperatures go way up, way beyond anything you’d see in a piston engine. And we don’t have any sensors to tell us. I’m proposing that we put a temperature sensor on a J47’s oil line and see how hot it gets when it’s flown at high altitudes at a high Mach number. That’s what happens in combat, for sure, and probably in a lot of the training.”
Shaddock and Baker looked dubious, but Vance went on.
“If it has a sustained high temperature for most of a flight, almost no oil will be getting through, and it will be tearing the heart out of the bearings. That would explain a lot of failures.”
Steve stopped shaking his head long enough to say, “Well, putting a sensor in is no big deal. We can go back out to Muroc tonight, put the sensor in tomorrow morning, and do a test flight tomorrow afternoon. But I think you are wrong, Vance. Maybe we ought to have a little side bet on this. Tell you what. If it runs hot enough
tomorrow to indicate a problem, I’ll buy dinner for all of us at Pancho Barnes’s place. If it doesn’t—you buy.”
Pancho’s place, the Happy Bottom Riding Club, was a home away from home for the test pilots and the longtime regulars at Muroc.
“I hate to take your money, Steve, but a bet is a bet. You’re on! But that’s not the only thing.” Vance pointed to the wiring leading to a thermocouple used to monitor engine temperatures. “What would it take to get a bulletin out to the field having the thermocouples on the fleet checked for accuracy?”
Vance knew the North American system of communicating with its field representatives was first-rate. Every tech rep would have a bulletin in his mailbox in the morning. They would run the tests the same day, and the results would be fed back in that night to North American for analysis and distribution.
“I can write it up this afternoon. What do you want me to say?”
“Just ask them to recalibrate all the thermocouples as soon as possible, and then recalibrate them after the next flight. I’ve got an idea that they are malfunctioning, and not registering the actual heat being produced. That would account in part for the reports on rotor blade erosion.”
“Can do, but it will take a few days; they cannot get the results back faster than they fly the airplanes.”
“Sure, of course, but tell them to send the results as they get them, not to wait until the test is complete.”
Shaddock agreed willingly. He trusted Vance’s instincts.
The following afternoon they were installing the sensor on the fourth prototype XP-86 when there was a yell of, “Stand clear,” as the nose gear collapsed without warning. The aircraft’s nose came down with a bang that had people running from all over the field to see what happened, while the tail flew up into the air, tossing workmen aside like dolls. The stabilizer was ripped where it
had lifted up through one of the maintenance stands, and the gear doors were smashed. Fortunately, no one was hurt.
Shaddock shook his head. “Before we do anything else, let’s get an adequate hydraulic system installed here. We can pull one off a B-25 and modify it so that it will work better than this. What do you think, Vance?”
“Man, with three thousand pounds of pressure, I can’t believe that it’s the hydraulic system. Let’s take a look at it.” Within an hour the F-86 was put on jacks, and they had the damaged nose gear doors removed.
Shannon asked, “Where is the ground safety pin?” A red-flagged pin was designed to go through the gear scissors to prevent a collapse. “The pin’s not in. Who is the crew chief?”
A crestfallen staff sergeant named Jensen moved forward. “I’m crew chief on this airplane, sir. I guess I forgot to put it in. We don’t usually use them.” Jensen reflexively touched the stripes on his sleeve, obviously worried that he might lose them if the accident was blamed on him.
Shannon slapped him on the back and said, “We all make mistakes, Sergeant Jensen. How about helping me find out what caused this one?” He nodded to Shaddock and Baker, signaling that they were to let him and Jensen work it out.
There was only room for one of them to get inside the narrow nose gear aperture, and they alternated, one moving in and one moving out. Shannon spotted the problem early but didn’t identify it—he wanted Jensen to find it. Finally Jensen said, “Sir, it looks like this drag brace is what’s wrong.” They knelt together on the ramp, peering upward. Jensen put his hand on the slim steel billet that was designed to go over-center when the gear was extended and keep the gear locked down. “Look, it’s rigged wrong—it’s not going down over-center.”
“You’re right, Jensen; congratulations, you’ve solved it. When this happens, the only thing that will keep the
gear from collapsing is the safety pin. We need them to redesign the part so that it has to go over-center every time.” Jensen grinned in relief, a little more confident about keeping his stripes.
Two days later, the XP-86 was ready to fly. Steve had carefully placed two sensors on the oil line connecting them to two instruments he had attached in the only space available, crowded on the left side of the cockpit.
Shannon talked to the test pilot, George Welch. “Georgie, my boy, you don’t have to do anything fancy. Just fly a normal intercept profile—rapid climb to altitude; cruise at high Mach for thirty minutes; make a high-speed descent and landing. Keep your eye on the two gauges, and note what they do temperature-wise. Don’t put any excessive g’s on the airplane—and don’t go supersonic.”
Welch didn’t even acknowledge Vance’s jest, just nodded and climbed into the airplane.
Forty-five minutes later Welch landed. “Both gauges went off the clock, Vance! I don’t know how hot they got, but they were pegged ten minutes into the climb and they stayed that way. Made me nervous! I don’t like it when the needles are bent into the side of the case.”
Shaddock and Baker were convinced—despite all the nonsense about jet engines running forever without oil, it was evident that the bearings in the J47 were being starved for lubrication at high altitudes and airspeeds. Best of all, it was a fairly cheap fix—existing engines could be retrofitted inexpensively, and the newer engines coming down the line could be fixed at virtually no cost. Then they checked the thermocouples, and Vance was right again. They needed to be recalibrated. When the reports began to come in from the field, they confirmed the problem. To get the correct engine power and to cut down on overheating, the thermocouples had to be recalibrated after every flight. It was tedious, but it would save engines.
Baker put his arm around Shannon’s shoulder. “Vance, I guess this means that we are buying you dinner at
Pancho’s. They are going to love you at North American and hate you at GE. The last thing they want is for the airframe manufacturer to be changing their engine design, even when they need it.”
“Well, Walter, what’s the problem? You and Steve fixed it; you are GE reps—you ought to get a bonus out of this. You write up the reports, I’ll sign them for North American, and you’ll be the most popular guys at GE headquarters.”
Shaddock shook his head. “I don’t know, Vance; that doesn’t seem right—I don’t want to cash in on your insight. You saw the problem; you should get the credit.”
“No, Steve, let’s do this my way. I’ll tell Dutch what happened, he’ll be happy with me, I’ll be happy with GE, and GE will be happy with you. It’s the government that benefits in the long run, so what difference does it make to any outsider who gets the credit inside GE? None, that’s what.”
They shook hands, but as they started to leave, Vance said, “Tell you what, though—give me and Sergeant Jensen credit for pointing out the gear problem. That’s out of your bailiwick and right in mine, and it’s the sort of thing Dutch loves, finding problems in the field.”
Vance was especially intent on keeping in Dutch’s good graces, because he had to tell him he was leaving Inglewood for at least four months, maybe more, to go to Seattle. This was one of the hazards of being an independent consultant. Tom and Harry were great for test work and were beginning to learn the maintenance and engineering end of the business, but Aviation Consultants, Incorporated, remained a one-man operation in the eyes of the major aircraft companies. When they had a problem, they wanted Vance, not one of his sons.
At Boeing, his old friend George Schairer had put in a special plea for him to come up and check into the beautiful but trouble-prone XB-47, which had flown for the first time on December 17, 1947. It was a revolutionary
airplane, with six jets and thirty-five degrees of sweep in the wing, but there were myriad problems. There had to be in such a radical step forward, but there was constant pressure from the Strategic Air Command to get the airplanes fixed and into operation. The B-47s were a weapon the Soviets could not counter, and the Air Force wanted them to be ready on twenty-four hours’ notice to attack with nuclear weapons.