Jet Aviation, which began business in Switzerland in 1967, is celebrating half a century in business. Now owned by General Dynamics, its history goes back further than 50 years to a decision by young Carl Hirschmann in 1940 to leave Paris for the U.S. ahead of the German blitzkrieg. In New York City, Hirschmann opened two successful delicatessens and ventured into the world of aviation, learning to fly and later acquiring a P-51 ...