The B-36 Peacemaker’s wing was sufficiently deep to allow technicians to access it and maintain the engines while the aircraft was in flight
The B-36 Peacemaker was designed in 1941 to be primarily a “10,000-mile bomber” with powerful defensive weaponry, six engines, and a performance that would preclude interception by fighters in the event that Germany invaded Britain and US bombers lacked the range to retaliate.
Because it was one of the first aircraft to incorporate a significant amount of magnesium in its structure, the bomber earned the moniker “Magnesium Overcast.” Its enormous size and intricate design, which required 27 miles of wiring, had a wingspan longer than the Wright brothers’ first flight, 400 cars’ worth of engine power, three five-room houses’ worth of internal space, and 27,000 gallons of internal fuel—enough to drive a car around the globe 18 times—earned it many accolades.
There was a lot of emphasis placed on the fact that the wing was deep enough to allow engineers to enter it and maintain the engines while in flight, as Peter E. Davies explains in his book B-36 ‘Peacemaker’ Units of the Cold War.
The replacement of several spark plugs, which was one of the more time-consuming maintenance tasks (partly due to the high lead content of the fuel), was eventually sped up by employing plugs with platinum tips that last longer. Early B-36 aircraft’s alternators were also notoriously faulty, frequently putting them in danger of losing all electrical power. If circuit breakers needed to be reset while the aircraft was in flight, the engineer could reach each engine’s electrical panel by navigating the catwalk inside the wing.
An engineer could enter and work inside the wing while it was in flight because of the wing’s 7.5-foot depth at its root. This became one of the many reasons why people were astounded by the B-36’s enormous size. In order to do limited in-flight engine monitoring and maintenance, crew members pulled themselves along a crawl-way that passed over the wheel wells and above the inner engines while in flight. At altitude, this meant enduring extremely low temperatures while donning oxygen masks in these empty, unpressurized spaces.
All members of the crew were involved in the aircraft’s preflight. Gunners might be asked to help with a variety of challenging jobs, such as lowering the main landing gear manually if it didn’t retract when it was engaged while the aircraft was in flight. A pair of crewmen (typically gunners) could reach the open gear well through a zippered flap at its edge after climbing out a catwalk into the wing. From there, they could manually lock the down-lock mechanism at low altitudes by kicking against it downward.
After repeated failed attempts to make the gear lockdown, pilot Lt. Col. Ed Sandin of the 5th SRW invented a risky technique for reaching down and inserting a main landing gear down-lock in flight. The task required working without a parachute while attempting to avoid peering down into an open abyss below due to the tight crawlway to this location over the wheel well.
B-36 ‘Peacemaker’ Units of the Cold War is published by Osprey Publishing and is available to order here.
Photo by: Lt. Col Frank F. Kleinwechter / U.S. Air Force
