By Tommy H. Thomason

Tuesday, March 9, 2010

Procrustes at BuAer

BuShips and BuAer were independent kingdoms in the Navy. While BuShips cooperated and coordinated with BuAer and the Chief of Naval Operations ruled them both, once the constraints were agreed to and the ships built or altered accordingly, BuAer's aircraft manufacturers had to design their airplanes within those constraints of hangar deck height, elevator dimensions, catapult and arresting gear capability, etc. Although bigger and more capable was usually reflected in a new class of ships, after the Korean War most of the Essex-class carriers received major upgrades to be able to handle larger and heavier airplanes.

As it happened, BuAer almost invariably required new aircraft to operate from the smallest carriers then in the fleet. Because of austerity measures, however, before or shortly after these aircraft arrived in the fleet, the carriers for which the new aircraft were constrained to be compatible had sometimes been decommissioned or were about to be. In a few cases, a new airplane never deployed from the smaller, less capable carriers that it had been designed to operate from even though they remained in service. For example, the McDonnell F4H Phantom specification incorporated the limitations of the Essex-class carrier and one set of carrier trials were accomplished on Intrepid, but the Phantom was never deployed on one.

That led me to revisit the SCB-125 forward elevator extension on the Essex-class carrier described in my prior post. While the A3D wasn't even close to fitting on this elevator and the other carrier-based fighters and attack aircraft didn't need the added length per se, there was one mid-1950s new program that did, the North American A3J Vigilante. Its folded width was 42 feet, providing the requisite one-foot clearance on each side. With the radome and tail folded, it was actually a bit shorter at 65 feet and a few inches than absolutely necessary. (The nose looks a little odd because the radome has been tilted upward into the folded position.)

There's a chicken and egg element to this theory, since I'm not sure of the relative timing of the SCB 125 elevator change and the A3J design freeze. In any event, unlike the A3D which it was intended to replace, the A3J never flew to or from an Essex-class carrier.

10 March 2020 Update: It subsequently occurred to me when I realized that the forward elevator was completely enclosed except for its aft end that a more likely reason for the extension was the desirability of having a tow tractor pull an airplane onto the elevator when it was on the hangar deck and ride along with it. It would also make it much simpler going down, with the tow tractor pushing it off the elevator onto the hangar deck.

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