by Bob Mann

A lot of words have been written, and rightly so, about the men who flew the B-29's in World War II and in Korea. But outside of the standard cliché, "Ground crews worked through the night to get a maximum number of planes in the air", little mention has been made of the mechanics who kept the aircraft flying. The cuts, the burns, the gashes, the falls, the lousy weather, these did not make the job of aircraft mechanic one of the cushiest in the Air Force. Even now,fifty years later, I can count over forty scars on my hands and forearms.

When you talk about working on airplanes, you have to start with the weather you were working in. We were lucky (?) being on Guam where we did not have to put up with frostbitten fingers. But Anderson AFB, at the northern end of the island, gets close to 200 inches of rain a year (usually in twenty minute showers), the temperature seldom gets below 80 degrees, and the humidity is so high that you had to keep a 100 watt light bulb burning in your clothes locker to keep the fungi from eating your clothes. We worked in fatigue pants and tee shirts, the standard USAF-issue coveralls being just too hot to put up with. A few of the hardier souls with very high pain threshholds stripped down to PT shorts and GI shoes, but this was generally considered extreme. I tried it once and burned both legs and my ribs on sun-heated aluminum within an hour.

To all of us who worked on it, the Curtis-Wright R-3350 radial engine was an object of consuming hatred. Basically, it was two nine cylinder engines mounted on a double throw crankshaft. Voila! Instant eighteen cylinder engine. And a mechanic's nightmare. The aircraft itself was bad enough to maintain, but those engines! The two banks of cylinders created by the double mounting were so close together that the mounting bolt flanges on the cylinder bases had to have the edges planed down in order to fit next to each other on the engine housing. This engine had a reputation of being a voracious eater of valves and rings, as well as a prodigious swallower of oil, and cylinder changes were almost as common as engine changes. There is a Rule that allows only those cylinders on the bottom of the engine to fail. This is so that the oil can run out of the engine housing and drip ceaselessly into the mechanic's hair, ears, nose and down the back of his neck So. You have pulled the cylinder, gotten your oil bath for the day, and held the cylinder in place while your fumble-fingered partner got the mounting bolts started. You've run the bolts, all twenty-four of them, in tight and torqued them down to Tech Order requirements. Are we done yet? Hell, no! You still have to safety wire those twenty-four bolts. Picture the rough-cast, quarter inch thick aluminum cooling fins projecting from the bodies of each cylinder. Picture the cylinder mounting bolt heads three quarters of an inch away from each other and only an inch and a half away from the mounting bolts of the cylinders in the other bank. Picture the safety wire that had to be strung and pulled tight through each bolt head. Picture the bloody mess where your hands used to be after you finished safetying twenty-four bolts and repeatedly dragging your knuckles across those cooling fins on each and every one of them.

I have always maintained that I can look at a man's right wrist and tell you if he had been a B-29 mechanic. The secret mark of the fraternity is found there: a scar an inch or so long on the inside of the wrist directly below the thumb. A new mechanic collected his scar the first time he was assigned to drain the front oil sump. The front sump was located at the bottom rear of the nose section of the engine housing, a few inches lower than the lip of the ring cowl on the front of the engine. To supposedly make access easier, Boeing engineers, none of whom had obviously ever worked as mechanics, placed an eight inch square door in the upper surface of the air inlet. Theoretically, this allowed the mechanic to reach upward through the hole, put his 3/4 inch box end wrench on the sump plug, and by pulling forward, loosen the plug. Well, first of all, that plug NEVER just gradually loosened. It came loose with a snap, at the precise moment you were applying even more pressure to make it come loose at all. Secondly, Boeing did not believe in wasting production time or coddling mechanics by rounding edges on access doors and hatches. The edge of the hole you were putting your arm through was SHARP, very, very sharp. Plug snaps loose, arm jerks towards you, wrist hits edge of hole, and another cursing mechanic is seen carrying his bloody box end wrench in his equally bloody hand down to the welding shop, where he will have the wrench shaped so that he can get to the plug from above, through the ring cowl opening in front of the engine, where there are no sharp edges.

After you got the plug out, the sump drained, the magnet on the sump plug checked for metal chips (hoping you wouldn't find any and have an engine change on top of everything else), the plug back in, tightened and safety wired, your fun and games with engine oil were far from over. There was still the rear sump to be drained and checked. That was usually a real adventure. First you scrounged up a short work stand and placed it under the nacelle.

Stepping up on the stand, the first step was to remove an access door approximately eighteen inches square. This allowed you to reach a similar door above it which formed part of the lower surface of the air intake. Removal of that door brought you to still another same-sized door on the upper surface of the air intake. Removal of that door finally got you into the bottom of the engine accessory compartment. CORRECTION: It allowed access to the accessory compartment. You got there by putting your right arm, clutching the inevitable 3/4 inch box end wrench and a pair of dykes for cutting the plug safety wire, above your head and into the hole you had just opened. The work stand was climbed step by step until your hips were level with the bottom of the nacelle and you head and arm were in the accessory compartment. Putting the wrench down somewhere handy, the safety wire was removed and the dykes dropped in your breast pocket, it being the only one reachable. The wrench was retrieved and placed on the sump plug. One handed pressure was applied until the plug (eventually) loosened. It was then backed off until held in by only a couple of threads. The wrench was again stashed somewhere, and you yelled down to your buddy through the inch or so of space between your body and the edge of the hole to pass up the oil drain hose. He, of course, is not there, having been dragged off ten seconds earlier by the crew chief to empty ash trays, fluff the pilot's seat cushion, and to perform other similar critical maintenance tasks.

So you climb down off the stand, carefully avoiding the sharp edges, put the drain line up in the hole and follow it with yourself. The drain line was a piece of two inch hose about eight feet long. The lower end was in a five gallon can and the upper end slipped over the outlet in the bottom of a rectangular metal box. The theory was that when you pulled the sump plug the oil drained into the metal box and ran down the hose into the waste bucket on the ground. That was the theory. In the real world, ruled by Murphy and his Law, no matter what the size and shape of the collector box, one of two things ALWAYS happened: the box overflowed or the line came off the outlet. Either way you got drenched from the middle of your chest to your toes with black, slimy, yucky engine oil. If you were very, very lucky, and the airplane had come back at midnight instead of half an hour ago, the oil had had a chance to cool. One usually was not lucky. It goes without saying that when hot oil is sloshed on you, you tend to jerk in a reflex action. Remember that little door by the front oil sump that you put your wrist through? Well, now you have your entire body through THREE doors. The swirling patterns to be seen in a mixture of black oil and fresh red blood are truly fascinating.

Difficult as the job of safety wiring the cylinder mounting bolts was, it did not even come close to the sheer frustration and muscle cramps that were the lot of any mechanic who had to change a fuel injection pump. On later models of the R-3350 engine, the old carburetor system was replaced with direct fuel injection. The required gasoline was sprayed directly into each cylinder through a nozzle mounted above the rear spark plug. The flow of fuel to these nozzles came from two pumps, each about fifteen inches long and eight inches in diameter, mounted on opposite sides of the upper accessory section of the engine. The forward edge of the pump mounting flange was no more than three inches from the firewall separating the power section from the accessory section of the engine. When a pump was replaced it was not the bolts on the rearward half of the flange that were a problem. It was the bolts on the forward side that were bad news. Because of the spacing involved, to reach the forward-side bolts you had to reach around both sides of the pump, rather like putting your arms around a horizontal log. In order to do this, the mechanic had to lean in through the main access hatch on the side of the nacelle and feel for the holes on the forward side of the pump. With no more than three inches of total clearance back there, you were reduced to the use of fingertips just to start the threads on several of the bolts. Once the bolts were started by finger (and you were reasonably sure they weren't cross-threaded), it was just possible to get a socket with a universal joint drive on the bolt heads. Forget the torque wrench; no way. Unfortunately, there was barely enough room to move the rachet one click. Turn one click, fingertip it back one click, forward one click, back one click ad nauseum. Finally, with cramps in every finger, the bolts were tightened down with what you hoped was sufficient torque to prevent any gasoline leakage. With the easy part of the job finished, those rotten bolts that couldn't be seen and could barely be touched had to be safety wired. This was strictly a feel job, and the accepted practice on my crew was to cut off a piece of wire about three feet longer than you really needed. The wire had to be run through each bolt head from the upper left quadrant to the lower right quadrant to prevent the bolts from vibrating loose. The technique generally used was to feel for the appropriate wire hole with the tip of the wire. When you found it, you pushed a minimum of twelve inches of wire through the hole. This brought the end of the wire below the pump, where it could be grabbed with a pair of pliers and carefully drawn tight without kinking the wire. If it kinked, you ripped everything out and started over. All this was going on while the mechanic was bending sideways and the edge of the hatch was digging into his ribs. Just to add a little more joy to the mechanic's day, there was usually an Airplane Driver down on the ground yelling up something encouraging, like, "Sergeant! What the hell's the holdup? We would like to get off the ground sometime soon so that we can get back in time for Happy Hour at the Club tonight. Speed it up, will you?" Exactly what was needed for motivation. It usually motivated me into dropping a bolt and spending an additional twenty minutes trying to find it.

My personal all-time favorite for raising the blood pressure was the reinstallation of the heat shield shrouding following a turbosupercharger change. Each nacelle on the B-29 held two turbosuperchargers, driven by engine exhaust gas diverted from the exhaust manifold, with a heat shield shrouding between the exhaust manifold and the engine accessory compartment. You had to pull the shrouding off when you changed a turbo, and reinstall it after the turbo was mounted and the holddown bolts safetied. There were several pieces of shrouding, and they fit together like a three dimensional jigsaw puzzle. In addition, they were usually badly distorted from the extreme temperatures that they were subjected to. Four pieces, the center, the upper center, upper forward and forward, had multiple planes, and all four overlapped forward and above the turbine bucket wheel. At the point of overlap, there was a bolt hole that ran through all four pieces. I defy anyone to get that hole lined up on the initial installation. The only way to handle it was to loosely install the shroud mounting bolts on all four pieces and then, starting with the bolts farthest away from the overlap, tighten here, loosen there, back and forth, back and forth, until eventually the holes in all four pieces lined up and you could run a bolt through them. Attacking the problem from the other direction, putting in the bolt and then trying to install the shroud mounting bolts never seemed to work, although I think every mechanic has wasted a half a day on it.

We mechanics were really pressed to prove the adage that where there's a will there's a way during the first six months of the Korean War/Conflict/Police Action/Whatever. The 19th Bomb Group was stationed down at the other end of the field, and on the 27th of June, 1950, they moved out for Okinawa and four years of combat missions. The maintenance people of the 19th stripped the base shops of every engine and spare part they could put their sticky little fingers on. In fact, they snuck up into our area in the dead of night and stole all four engines off 44-86267, one of our shiny new airplanes. When the crew of 267 got out to the flight line the morning of the 27th, the Bomb Group was gone, there was a jack under the tail and four gaping holes in the wings where the engines used to be. With the Bomb Group taking everything loose, and some things that weren't, the only parts we had available to us were those we had on hand in the Squadron Tech Supply hut. It wasn't much to keep twelve airplanes flying. Whenever we had to replace an engine, we had to send a wire to Japan, and then wait for them to pull an engine out of the pipeline and divert it to Guam. As for getting replacement parts, forget it. So, to paraphrase a current expression, we went into creative maintenance. One of our band of Rock Happy Fools spent all of his spare time boondocking (wandering through the jungle looking for Japanese souvenirs). Most of the time his finds were highly useful items such as 155 mm cannon barrels without breech blocks, rusted out jeeps and weapons carriers, fifty-five gallon drums filled with unidentifiable liquids, and similar goodies. In our hour of travail he came through. In a small overgrown WW II dump between Anderson and Northwest Fields he came across a dozen large crates containing brand new R-3350 engines. They had been sitting there since 1945, but the cosmoline was still thick and, when we got the crates open, found that the desiccant bags were still active. We had our engine parts. A veritable plethora of magnetos, distributors, fuel and oil pumps, cylinders, injection valves, prop governers, all those good things. To keep the paper shufflers (and the Inspector General) off our necks, whenever we replaced a bad unit, say a magneto, with a dump part, we also swapped the manufacturer's data plates. This apparently kept the same model and serial number on the engine that the paperwork said was supposed to be there. If we hadn't covered our tracks on this, half the brass at FEAMA (Far East Air Material Area) would be swarming all over us, grounding everything in sight, while they tried to determine what to do about a problem that was not covered by The Book. It should be pointed out that the 'dump parts' were used for interim replacement only; they were carefully checked for interchangeability and performance, and were immediately replaced when legitimate parts became available. Needless to say, we didn't tell the Operations people what we were doing, either. The flight crews were insecure enough without knowing that some very essential parts of their engines had come out of a dump.

All I've talked about to this point is the problems B-29 mechanics had with the engines. Don't get the idea that the airframe maintenance was any easier; it wasn't. In fact, I am convinced that Boeing had a crew of people that went over all prototypes, saying things like, "This fitting is too easy to get at for maintenance, weld a panel in front of it." Have you ever changed a rudder in a fifteen to twenty mile an hour crosswind and have a hinge bolt hang up? Gotten drunk on, and suffered the world's worst hangover from, gas fumes flowing into your face while changing a center wing tank fuel booster pump? Had a main gear wheel dropped on your foot when pulling it for a brake change? Had to dump the relief can after a flight because the flight crew "forgot"? Spent two weeks scrubbing exhaust stains on the flaps and nacelles because the CO thought they looked "messy"? Tried to talk reason to a know-it-all Second Lieutenant, without getting court-martialed, who insisted that the clutch was slipping on a direct-drive electric flap motor? Passed out from the 120 degree heat in the tail section while installing the cables on a new elevator? Spent seven hours on a Saturday "looking busy" on the engines of an in-commission airplane because the CO thought a visiting VIP might want to inspect the flight line? And then have him drive past without stopping anywhere but the Officer's Club? Had a brand new junior assistant deputy OJT engineering officer order you to spend ten hours changing a cylinder because of low compression when experience told you it was probably only carbon on the valve seat that could be popped off in a few seconds by rapping the rocker arm with a mallet? Risked losing a hand every time you reached across the edge of the bomb bay doors to put a down lock on the door actuator? Got second degree burns from putting your hands on the aircraft skin in the middle of the day? Worked through the night to have the plane ready for an 0800 takeoff, only to be told at 0730 that the flight was canceled? I don't regret my years as a B-29 mechanic; in fact, I loved them. But it would have been so much nicer, if even just once, someone from the clean khakis crowd in Engineering, Operations and the CO's office had come out to oil and grease land and said, "Nice job, guys."

Bob Mann
rambert094@msn.com