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Studies of midair collisions reveal certain definite warning patterns. It may
be surprising to learn that nearly all midair collisions occur during daylight
hours and in VFR conditions. Perhaps not so surprising is that the majority happen
within five miles of an airport, in the areas of greatest traffic concentration,
and usually on warm weekend afternoons when more pilots are doing more flying.
Not What You Might Expect
Also surprising, perhaps, is the fact that the closing speed (rate at which two
aircraft come together) is relatively slow, usually much slower than the airspeed
of either aircraft. In fact, the majority of in-flight collisions are the
result of a faster aircraft overtaking and hitting a slower plane.
Statistics on 105 in-flight collisions that occurred from 1964 to 1968 show that
82 percent had convergence angles associated with one aircraft overtaking another.
Specifically, 35 percent were from 0 to 10 degrees - straight from behind. Only
5 percent were from a head-on angle. These numbers, plus the fact that 77 percent
occurred at or below 3,000 feet (with 49 percent at or below 500 feet) imply
accurately that in-flight collisions generally occur in the traffic pattern and
primarily on final approach. Collisions occurring enroute generally are at or
below 8,000 feet and within 25 miles of an airport.
No Pilot is Immune
The pilots involved in such mishaps ranged in experience from first solo to
15,000 hours, and their reasons for flying on the accident day were equally varied.
Some examples:
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A 19-year-old private pilot flying a VFR cross-country in a Cessna 150 collided
with two seasoned airline pilots flying a Convair 580 under IFR control.
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A 7,000-hour commercial pilot on private business in a twin Beech overtook a
Cherokee on final, which carried a young flight instructor giving dual to a
pre-solo student pilot.
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Two commercial pilots, each with well over 1,000 hours, collided while ferrying a
pair of new single-engine aircraft.
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Two private pilots with about 200 hours logged between them collided while on
local pleasure flights in Piper Cubs.
There is no way to say whether the inexperienced pilot or the older, more experienced
pilot is more likely to be involved in an in-flight collision. A beginning pilot has
so much to think about he may forget to look around. On the other hand, the older
pilot, having sat through many hours of boring flight without spotting any hazardous
traffic, may grow complacent and forget to scan. No pilot is invulnerable.
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