The military has quite a few aviation accidents every year even in peacetime. Military planes don't just cruise from place to place like airliners. They do things like low-altitude high speed flight, dogfighting, gunnery, carrier operations, etc. that by its very nature is dangerous. Throw into the mix the fact that military planes are often maintained by teenagers and the relatively low flying experience of military pilots and it's amazing the accident rate isn't higher. A military pilot can go from first flight to the cockpit of a fighter in less than 500 flying hours contrasted to thousands of hours required for airline pilots. Military pilots are lucky to get 250 hours a year of flying during peacetime as contrasted to 80 hours a month (FAA limit) for airline pilots.

Accident rates vary widely depending on the type of military plane we're discussing. Fighters crash more often than bombers or transports but they're flown a lot harder, too. Helicopters have the unfortunate tendency to crash in the best of times.

Even within a category like fighters, some planes have a much higher accident rate than others. For example, so many F-16s have gone down over the years that one derisive nickname for the plane is "Lawn Dart". Harriers are among the most crash prone planes in service for a variety of reasons. Still, the accident rates are lower than they were in the 1950s through 1970s. Old planes like the F-100 had a much higher accident rate than the F-16 despite it being a much simplier plane.

Throw in wartime in places like North Vietnam with some of the heaviest air defenses anywhere on Earth and commanded by morons like LBJ and McNamara the loss rate becomes very high. If you want to hear bitterness, ask a former F-105 pilot describe the utter stupidity of LBJ's and McNamara's role in commanding the air war over Vietnam.

From this source:

It was a poor set of Rules of Engagement (ROE) and overly centralized control of targeting which helped the North Vietnamese air defenders score so many American kills. An example of the former is given in "On Yankee Station", by Commander John B. Nichols:



SAM sites were another case in point. Secretary of Defense McNamara knew that Soviet technicians were installing and often operating the new surface-to-air missile batteries. Because of concern about harming 'neutral' Soviets, U.S. TACAIR crews were ordered by the Pentagon to pass up these sites even when they were vulnerable during construction. One F-4 squadron commander off USS Midway actually watched the SAM site being built that eventually shot him down in 1965. (23)

An example of the latter is:

Lyndon Johnson boasted that `they can't bomb an outhouse without my approval' and thought that was something to be proud of. But whether one regards that situation as laudible or ludicrous, the fact is it didn't work and it didn't make sense. At times it seemed as if we were trying to see how much ordnance we could drop on North Vietnam without disturbing the
country's way of life. (24)