I performed a fairly in-depth study of homebuilt accidents towards the end
of last year. The October issue of KITPLANES magazine will include an
article summarizing my results and conclusions.

During my analysis, I looked at the records of individual designs, thought
I didn't include the results in the article. Even though I performed my
analysis on a three-year period, the number of accidents of most particular
types is still fairly low that minor aberrations cause significant changes.

For instance, if there are 2000 examples of type "A" and 200 examples of
type "B", one or two extra crashes will affect the stats for Type "B" a lot
more than Type "A". If 20 Type "A" planes and 2 type "B" planes crash,
they both have the same accident rate. If both have two additional
accidents, Type "B"'s rate will now be almost *double* Type "A"'s. But
does that truly mean that "B" is twice as dangerous as "A"?

We also get into the aircraft type and aircraft operating mode issues. On
my first pass, I found one type of homebuilt with a significantly higher
accident rate than the rest. When I looked closer, I realized that this
was an amphibian...and a lot of the accidents were during water operations.

So I'm reluctant to point fingers are individual aircraft types. Here's a
list of the fleet accident rate (what percentage of a particular type
crashes in an average year) for ten major homebuilt kit companies. Note
that the statistics for companies with multiple types are grouped together
(e.g. the RV series is lumped under one, not listed individually). Only
aircraft listed as being licensed were included...many homebuilts of these
types are on the registration rolls but have the certification type column
blank.

The aircraft included are (in alphabetical order): Avid, Glasair, Glastar,
Kitfox, Lancair, Long EZ, RANS, T-18, Vans, Velocity. Note that this order
does NOT match that of the table below, nor does it include the amphibian
type I mention above.

Annual Accident Rate
% of Fleet
A 1.3%
B 1.2%
C 1.8%
D 4.9%
E 0.9%
F 1.0%
G 0.7%
H 2.4%
I 1.9%
J 2.9%


Ron Wanttaja