Eddie Rickenbacker:
His parents immigrated to the US from Switzerland and upon arrival in Ohio changed the spelling of their name from Rickenbacher to Rickenbacker so it would sound less German. Gaining fame as a popular race car driver at the start of he attempted to enlist in the US Army to become a pilot. However, US Army counter-intelligence became suspicious as to why his parents changed the spelling of their last name, and the fact that he drove a Duesenberg race car, a car built by a set of German Brothers, he was denied flight training.
A spokesman for the US Army Signal Corps stated:
"We don't believe that it would be wise for a pilot to have any knowledge of engines and mechanics. Airplane engines are always breaking down, and a man who knew a great deal about engines would know if his engine wasn't functioning correctly and be hesitant about going into combat."
Eddie Rickenbacker enlisted in the army as an automobile driver and in France was a driver on the staff of General Blackjack Pershing and met General Billy Mitchell who approved him for flight training. Eddie Rickenbacker then went on to claim 26 air to air kills in WWI becoming America's highest scoring ace.
Source: pg 86 & 87 Mavericks of the Sky The First Daring Pilots of the U.S.Air Mail by Barry Rosenberg & Catherine Macaulay 2006
Just proves that even in 1917 the military could do stupid stuff. ::)