2007 Homebuilt Fleet Size Statistics

[Ron Wanttaja]

Rollicking good time in the Wanttaja household lately, with another set of
homebuilt registrations statistics/homebuilt accident statistics analyses under
way.

Based on my 4 January 2008 FAA registration database, there are 30367
Experimental/Amateur-Built aircraft registered in the US. This does not include
homebuilt aircraft that are not listed as having airworthiness certificates
(which does not mean they don't, of course).

The fleet size increased by 940 aircraft vs. my January 8 2007 database. This
is roughly equivalent to the preceding few years, but is down a bit from the
early 2000s. However, in the past several years, the FAA has been
de-registering a bunch of aircraft. This may be affecting the statistics to
some extent.

The following table shows the percentage of the total homebuilt fleet of
particular homebuilt types:

Aircraft %
RV-6 5.5% (e.g, 5.5% of all homebuilts are RV-6s or RV-6As)
Kitfox 3.2%
RV-4 3.1%
Pitts 3.0%
Bensen 2.5%
RV-8 2.3% (Both taildraggers and trigear types)
Lancair (All) 2.3%
Glasair 2.1%
RANS (All) 1.9%
Challenger 1.8%
Long-EZ 1.6%
Stolp 1.6%
Rotorway (All) 1.6%
Avid 1.6%
Starduster/Acroduster 1.5%
RV-7 1.5% (Both taildraggers and trigear types)
Zenair 1.4%
KR-2 1.1%
Pietenpol 1.1% (Includes Grega versions)
T-18 1.1%
Glastar 1.0% (Includes Sportsman models)
Baby/Junior Ace 0.9%
Fly Baby 0.9%
RV-9 0.9%
Christen Eagle 0.8%
Quickie 0.8%
Velocity 0.7%
Lancair IV 0.7%
Sea Rey 0.6%
RV-3 0.6%
Murphy 0.6%
BD-4 0.5%
Sonex 0.5% (Includes Waiex)
Cozy 0.5%
RV-10 0.3%
BD-5 0.3%
Europa 0.2%

About 14% of the whole homebuilt fleet are Vans designs.

Accident analyses are fascinating, as always. Results should be in Kitplanes in
October.

Ron Wanttaja

[Gig 601Xl Builder]

Ron Wanttaja wrote:
> Rollicking good time in the Wanttaja household lately, with another set of
> homebuilt registrations statistics/homebuilt accident statistics analyses under
> way.
>

interesting data there Ron. RVs make up 14.2% of the fleet. That is
impressive.

How are you pulling the data for those folks that don't keep the
designer's name on the registration in any way?

[Ron Wanttaja]

On Wed, 02 Apr 2008 08:24:07 -0500, Gig 601Xl Builder
> wrote:

> Ron Wanttaja wrote:
> > Rollicking good time in the Wanttaja household lately, with another set of
> > homebuilt registrations statistics/homebuilt accident statistics analyses under
> > way.
> >
>
> interesting data there Ron. RVs make up 14.2% of the fleet. That is
> impressive.
>
> How are you pulling the data for those folks that don't keep the
> designer's name on the registration in any way?

No way of telling if they call their RV-6 a "Jones Special," of course. Most
keep *some* sort of relationship with the designer/kit maker's designation for
the aircraft.

When developing filters, I start with something fairly broad, then examine the
hits to discover what other designations might be used for the aircraft, then
tune from there.

For example, when trying to spot the Glastars, I initially ran a search on just
that name. Looking at the listings, I then see that a numeric designation of
the design can be "GS-1" or "SH-4". So I add variations of them to the
filter... I look for "GS-1", "GS 1", and "GS1", and the same variations on SH-4.

Unfortunately, when I search for "*GS 1*", it ALSO hits the Schweizer SGS 1-23
glider. So I have to add exclusions for similar but incorrect designations.
Sometimes I have to add a filter just to keep one sneaky incorrect entry from
popping up.

Here are my ultimate criteria for finding the Glastars:

(Like "*SH-4*" Or Like "*SH4*" Or Like "*SH 4*") And Not Like "*CONTROL*" And
Not Like "*Sportsman*"

or

(Like "*SH-4*" Or Like "*SH4*" Or Like "*SH 4*") And Not Like "*CONTROL*" And
Not Like "*Sportsman*"

I exclude "Sportsman" from my Glastar search because I have a separate filter
for the Sportsman (which, in itself, includes filters to eliminate the Wag-Aero
Sportsman and other planes using that name). I eventually had to include a
year-of-manufacture filter just to get rid of some of the non-Glastar variants.

I've seen listings where they *spell* out the number (e.g. "BD FIVE"), but
they're rare enough that I don't routinely add that kind of filter. The
filtration is never perfect, of course. I don't catch the misspellings
("Glassair") or name abbreviations ("STRD HMLTN SUPER IIS") and other such
variations. In my experience, though, the variations are rare enough that they
don't really impact the numbers much.

The list I posted accounts for about *half* the total number of Experimental
Amateur-Built registrations. The remaining types are a wide variety...
Breezies, CA-65s, Stephens, Miniplanes, Jungsters, Cassutts, Sonerais, etc. A
few dozen of one type, a hundred or so of another, it adds up. If anyone feels
I left a major type off my list, let me know.

Ron Wanttaja

[es330td]

On Apr 2, 10:55*am, Ron Wanttaja > wrote:
> On Wed, 02 Apr 2008 08:24:07 -0500, Gig 601Xl Builder
>
> > wrote:
> > Ron Wanttaja wrote:
> > > Rollicking good time in the Wanttaja household lately, with another set of
> > > homebuilt registrations statistics/homebuilt accident statistics analyses under
> > > way.
>
> > interesting data there Ron. RVs make up 14.2% of the fleet. That is
> > impressive.
>
> > How are you pulling the data for those folks that don't keep the
> > designer's name on the registration in any way?
>
> No way of telling if they call their RV-6 a "Jones Special," of course. *Most
> keep *some* sort of relationship with the designer/kit maker's designation for
> the aircraft.
>
> When developing filters, I start with something fairly broad, then examine the
> hits to discover what other designations might be used for the aircraft, then
> tune from there.
>
> For example, when trying to spot the Glastars, I initially ran a search on just
> that name. *Looking at the listings, I then see that a numeric designation of
> the design can be "GS-1" or "SH-4". *So I add variations of them to the
> filter... I look for "GS-1", "GS 1", and "GS1", and the same variations on SH-4.
>
> Unfortunately, when I search for "*GS 1*", it ALSO hits the Schweizer SGS 1-23
> glider. *So I have to add exclusions for similar but incorrect designations.
> Sometimes I have to add a filter just to keep one sneaky incorrect entry from
> popping up.
>
> Here are my ultimate criteria for finding the Glastars:
>
> (Like "*SH-4*" Or Like "*SH4*" Or Like "*SH 4*") And Not Like "*CONTROL*" And
> Not Like "*Sportsman*"
>
> or
>
> (Like "*SH-4*" Or Like "*SH4*" Or Like "*SH 4*") And Not Like "*CONTROL*" And
> Not Like "*Sportsman*"
>
> I exclude "Sportsman" from my Glastar search because I have a separate filter
> for the Sportsman (which, in itself, includes filters to eliminate the Wag-Aero
> Sportsman and other planes using that name). *I eventually had to include a
> year-of-manufacture filter just to get rid of some of the non-Glastar variants.
>
> I've seen listings where they *spell* out the number (e.g. "BD FIVE"), but
> they're rare enough that I don't routinely add that kind of filter. *The
> filtration is never perfect, of course. *I don't catch the misspellings
> ("Glassair") or name abbreviations ("STRD HMLTN SUPER IIS") and other such
> variations. *In my experience, though, the variations are rare enough that they
> don't really impact the numbers much.
>
> The list I posted accounts for about *half* the total number of Experimental
> Amateur-Built registrations. *The remaining types are a wide variety...
> Breezies, CA-65s, Stephens, Miniplanes, Jungsters, Cassutts, Sonerais, etc.. *A
> few dozen of one type, a hundred or so of another, it adds up. *If anyone feels
> I left a major type off my list, let me know.
>
> Ron Wanttaja

Maybe this will help you in classifying entries. In real life my job
is database programming and data management. In situations like this
I'll put the data into a temporary table with an additional column
called "Processed" I'll run my statements wherein I am trying to find
a particular pattern and when I get a good match, e.g. Schweizer SGS
1-23, I would mark it as processed. When I later try to match the GS
1 entries I can exclude the ones that were already processed so that
my pattern that is a little broader than I'd like has most of the
potential bad matches already moved from its source list.