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meteorite impact physics item

The statistics are a very interesting matter to explore concerning
meteorites for many classes of potential targets from people to houses,
but I would agree you should use stats for general guides and not as a
definitive scientific examination of individual incidents.  As an
experimental physicist, I would certainly want to know if expected forms
of meteoritic material were or were not found if I were concerned about
a particular case.  

A physics point that may help us during discussions of consequences of
meteorite impacts is that the composition and size of the impactor is
critical even at the fairly high altitudes of aircraft.  If you plug in
the drag forces and types of ballistic coefficients you expect for
smaller meteorites (grams to many kilograms) you find that even the
"slight" amount of atmosphere above a few kilometers is enough to
eliminate most of the original resultant velocity of the meteoroid, and
you are likely left with something traveling at several hundred miles
per hour; i.e., terminal velocity, akin to the notion of someone
dropping from a high altitude and ceasing acceleration at some point. 
You do not have to do the physics yourself, a number of books on
meteorites show one such set of graphs that illustrate this (did I see
this reproduced for vertical arrival in Norton's excellent book?).  The
remaining kinetic energy that can be converted is proportional to the
square of the speed, thus the kinetic energy is *much* less at a
potential impact point than would be the case if there were no
atmosphere.  (Of course the graphs show that for a much larger mass
penetration at high fractions of the original relative speed is
possible.  This line of discussion is relevant to people discussing the
composition and size of objects that penetrate to particular altitudes
before exploding with dramatic effect.)  

It is probably reasonable that at such velocities a meteorite would
leave physical evidence scattered about a vehicle. The effect of the
environment before collection has to be considered of course (e.g., in
Revelstoke only a couple of grams of C1 was recovered despite a large
bolide- check out the British Catalogue; and Pasamonte was huge but only
3-4 kg were recovered; of course, a vehicle acts something like a trap,
so presumably evidence should be there if struck unless it were
unexpectedly water soluble??).