I'm working on a replica 1913 airplane, in which the pilot's shoulders stick out a ways above the fuselage, so that it's impossible to install shoulder harness with the proper angle without having them outside the airplane. It would be possible to install a second seat belt under the pilot's armpits, across his chest, attached to the upper longerons, to perform the same function as shoulder harness, but are there physiological reasons why this would be a bad idea??
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