Single-Seat Accident Records (Was BD-5B)

On Sat, 15 Nov 2003 20:44:32 GMT, Ron Wanttaja wrote:

OVERALL ACCIDENT RATE:

Let's look at the overall accident rate for the homebuilt fleet and the
individual types. The "Accidents" is the total number of accidents vs. the
number of that type on the Jan 2003 register, and the "Fatals" column is
the number of accidents in which the pilot was killed.

Accidents Fatals
All Homebuilts 11.1% 3.2%
Fly Baby 5.7% 1.9%
BD-5 27.2% 11.1%
RV-3 8.2% 2.9%

An email discussion with a fellow netter pointed out that these figures are
liable to misinterpretation.

The rates shown above are over the 14-year period of the data collected,
and are not *ANNUAL* rates! Divide by 14 to get the average annual
accident and fatality rate. Or, heck, just read it off this table:

Acc. Fatals
1990 1.33% 0.45%
1991 1.17% 0.38%
1992 1.36% 0.44%
1993 1.32% 0.36%
1994 1.24% 0.34%
1995 1.29% 0.43%
1996 1.14% 0.32%
1997 0.99% 0.34%
1998 1.19% 0.34%
1999 1.09% 0.30%
2000 1.14% 0.26%

Ron Wanttaja

On Sun, 16 Nov 2003 18:28:58 +0000, Ron Wanttaja wrote:
...
The rates shown above are over the 14-year period of the data collected,
and are not *ANNUAL* rates! Divide by 14 to get the average annual
accident and fatality rate. Or, heck, just read it off this table:
...

Thanks, Ron!

You used the number of registered aircrafts as of January 2003, right? How
many aircrafts do you think have been removed from the register during
these 14 years? If this is a substantial number, they would push the
accident rate further down.

- Holger

On Sun, 16 Nov 2003 11:16:39 -0800, "Holger Stephan"
wrote:

On Sun, 16 Nov 2003 18:28:58 +0000, Ron Wanttaja wrote:
...
The rates shown above are over the 14-year period of the data collected,
and are not *ANNUAL* rates! Divide by 14 to get the average annual
accident and fatality rate. Or, heck, just read it off this table:

Thanks, Ron!

You used the number of registered aircrafts as of January 2003, right? How
many aircrafts do you think have been removed from the register during
these 14 years? If this is a substantial number, they would push the
accident rate further down.

That was so for the 14-year rate in the first posting, but for the
annual-rate table, I used the number of homebuilts that the EAA said was on
the registry for that year. So the per-year data should be fairly
accurate.

I got that data several years ago, when I was researching my homebuilt
registration-statistics articles for KITPLANES. Here's the breakdown of
the per-year registration, with the net gain over the previous year.
"Total" is the total number of homebuilts on the registry that year, "Net"
is the net percentage increase in the number of homebuilts over the
previous year.

Year Total Net
1990 13432 6.1%
1991 14227 5.9%
1992 14916 4.8%
1993 15068 1.0%
1994 15995 6.2%
1995 16876 5.5%
1996 17837 5.7%
1997 18732 5.0%
1998 19643 4.9%
1999 20494 4.3%
2000 21087 2.9%

While the figures through 2000 were declining, they came up in subsequent
years:

2001 22186 5.2%
2002 24496 10.4%
2003 25656 4.7%

5.2% was the average annual net increase between 1990 and 2003. I took a
cut at adding the accident aircraft back into the totals to get an
approximation of the number of new homebuilts registered that year (the net
value above stems from the new-registered homebuilts minus those removed
from the registry in a given year). However, the FAA doesn't automatically
remove crashed planes from the registry, so the approximation wouldn't
work.

Ron Wanttaja

On Sun, 16 Nov 2003 21:00:00 +0000, Ron Wanttaja wrote:
...
That was so for the 14-year rate in the first posting, but for the
annual-rate table, I used the number of homebuilts that the EAA said was
on the registry for that year. So the per-year data should be fairly
accurate.

Ah - then it is good, thanks Ron. Of course, for us as individuals, the
probability of driving a vehicle that will kill us may be more important
than the probability of this happening during a certain year within the 14
year period.

- Holger