Free Freedom's Forge by Arthur Herman Page A

section. More than a thousand test drawings had to be thrown away for every one incorporated into the overall plan.
    For their pressurized cabin, Wells and his team worked out a three-“bubble” system instead of trying to pressurize the entire plane—much less complicated and much safer, since sudden loss of pressure in one “bubble” wouldn’t mean loss of pressure in the rest. The first bubblewas the cockpit area, where the pilot, co-pilot, engineer, and radio operator would sit. The second was in the midsection where the gunners were, and the third was for the gunner in the rear. He would be effectively locked in for the duration of the flight, sometimes for eighteen hours—doomed to be the loneliest man in the Army Air Forces. 24
    The guns were a problem. Conventional turrets like those on a Flying Fortress or Liberator couldn’t be pressurized, and areodynamics expert George Schairer pointed out they would also add exterior drag on a plane that could tolerate very little drag. So Schairer proposed leaving them out altogether. After all, the B-29 was designed to fly higher and faster than fighters could reach, anyway. Why worry about protection against a theoretically nonexistent threat?
    The Army thought about this. Then, a few days after Pearl Harbor, General Kenneth B. Wolfe, the man who would eventually head the B-29 program, sent his assistant Jake Harmon out from Wright Field along with tech chief Roger Williams. They read Wells and Schairer the riot act. There not only would be gun turrets on the B-29, he told them, but retractable ones, both below and above the fuselage. The Boeing men retorted that this would make pressurizing the interior cabin impossible. They explained the unacceptable drag and other technical problems that would arise. Harmon was sympathetic but adamant.
    “The general will bust us both to second lieutenants,” he told Wells, if he and Williams didn’t come back with a pledge from Seattle to install those gun turrets. 25
    There was some silence in the room. Then Roger Williams happened to mention something he had seen demonstrated at Wright Field by the General Electric Company, an electronic device for aiming and firing the machine guns of fast-flying aircraft: the first onboard airplane computer.
    GE’s little machine was like the fire-control systems that had been on Navy warships for years—but they were bulkier and slower and far less precise than a fighter pilot would need. This one could not only aim every gun on a warplane but fire them as well, while correcting errors in direction and angle of deflection simultaneously. Its “brain” was a tiny black box connected to a motor called a selsyn, which wasable to compute in fractions of a second the speed and direction of an incoming plane, including variables like wind speed and exterior temperature, then could either aim weapons for firing separately at a fighter making a sweeping pass, or have the guns all converge on a single “aiming point”—all at the touch of a button. 26
    Wells made a call to General Electric, and working with Sperry Gyroscope, Boeing and GE were able to create a remote fire-control system for the superbomber—the first “smart” automated weapons system and ancestor of today’s precision-guided munitions and “smart bombs.”
    That left what to do about the wings. The B-29 would be twice the size of the B-17, but had to have the same drag in order to get the high-altitude performance the Army was demanding. Aerodynamics expert Schairer designed the wing with sleek narrow lines and new lighter metals for the engine nacelles and supercharger system for the Wright 2200-horsepower R-3350 engines. But it was still not enough.
    The result was Fowler flaps, developed by aviation engineer Harlan Fowler. They were in effect airfoil spoilers that—unlike most flaps—didn’t just hinge down from the wing. Boeing built them so that they actually slid out from inside the wing and then rotated down,