BD5B

On Thu, 13 Nov 2003 23:23:22 -0600, Big John
wrote:



No one has posted a follow up with the name of the BD5 pilot, and
details of the accident (1000 ft short on final). You don't see many
BD5 accidents but there are not a lot flying so statically the
accident rate is probably pretty high vs other homebuilts with a lot
completed and flying?

Man those BD5's just don't seem like a good idea. Tiny, high stall
speed, tight engine compartment, and the pilot sits right on the
bottom of the fuselage.

The airplane has been discussed in this group previously and my
recollection is that it has a very high fatal accident rate. It's
first flight accident rate is also very high. Perhaps Ron Wanttaja
can step in with his always meticulous statistical analysis.

Corky Scott

On Fri, 14 Nov 2003 13:57:03 GMT,
(Corky Scott) wrote:

Man those BD5's just don't seem like a good idea. Tiny, high stall
speed, tight engine compartment, and the pilot sits right on the
bottom of the fuselage.

The airplane has been discussed in this group previously and my
recollection is that it has a very high fatal accident rate. It's
first flight accident rate is also very high. Perhaps Ron Wanttaja
can step in with his always meticulous statistical analysis.

Damn, Corky, were you lurking in the back of the EAA Chapter 26 meeting
last night? I'm in the process of doing a detailed homebuilt accident
analysis, and presented my initial results.

Unfortunately, the year I chose for my in-depth analysis didn't include any
BD-5 crashes, so it's of no use for us in this case. Let's do a simpler
comparison. I ran the NTSB database for the accidents since January 1,
1990:

Total Amateur-Built Accidents: 2881
Total BD-5 Accidents: 22

BD-5s were involved in 0.8% of all homebuilt accidents, and in 1.1% of all
fatal homebuilt accidents. Due to the small size of the sample, this may
not be a significant difference (it's only three accidents extra over 13
years).

Looking at the FATALITY rate:

Total Amateur-Built Fatal Accidents: 837 (# of accidents, not fatalities)
Total BD-5 Fatal Accidents: 9

Homebuilt fatal accident rate: 837/2881, or 29.1%
BD-5 fatal accident rate: 9/22, or 40.1%

But what of the accident ratio in comparison to the size of the homebuilt
fleet? Let me "Back Out" some data that might let us make a comparative
analysis.

The January 2003 FAA database listed 25,886 aircraft as being in the
Experimental Amateur-Built category. The same database has listings for
237 BD-5s, of which 81 are listed as having Experimental Amateur-Built
certification.

Before I go on, allow me to explain the difference. Database listings
include a field for the category the aircraft is certified in. If the
field is blank, the usual process is to assume the airplane has received an
N-number but has not yet been approved for flight. My past analysis
indicates this is not necessarily the case; for instance, John Ammeter's
RV-6 (which flew something like ten years ago) STILL doesn't have an entry
in the Certification block, and, with Juan's help, I uncovered one BD-5
(not one of his, BTW) that made its first flight about five years after
being listed as certified.

Back when I did my first registration analysis, I found about 36,000
aircraft listings with "homebuilt-like" names, but only about 22,000 of
them (this was in 1997) were actually listed as certified. The FAA and EAA
only count those listed as certified, so the published figure is in the
20,000 range instead of in the 30,000s.

So...officially, we should only use the 81 BD-5s for analysis. Due to the
uncertainty, I'll list the figures for the full fleet as well. BTW, I used
"BD-5", "BD 5", "BD5", and "BEDE 5" (with appropriate wild cards) as my
search terms.

Anyway, to the stats:

Total homebuilts in 2003: 25886
Total certified BD-5s: 81
Total listed BD-5s: 237

Lets compare the number of accidents over the past 13 years with the
current number of homebuilts. We'll add the accident airplanes back into
the current fleet for a baseline.

This doesn't, in itself, produce a viable statistic. But it is useful in
comparing between aircraft types.

Total homebuilts plus accidents: 28767
Total certified BD-5s plus accidents: 103
Total listed BD-5s plus accidents: 259

(Note that the NTSB accident listings make no differentiation whether the
accident aircraft had a blank in the certification status field)

Percentages:

Total homebuilt accident rate: 10%
Total certified BD-5 rate: 21%
Total all-listing BD-5 rate: 8.5%

So whether the BD-5 is twice as bad as the main fleet or a little bit
better really depends on your interpretation of the certification data. By
the FAA and EAA's interpretation, the BD-5's accident rate is twice that of
the main homebuilt fleet.

Ron Wanttaja

In article , Ron Wanttaja
writes:


Total homebuilt accident rate: 10%
Total certified BD-5 rate: 21%
Total all-listing BD-5 rate: 8.5%

So whether the BD-5 is twice as bad as the main fleet or a little bit
better really depends on your interpretation of the certification data. By
the FAA and EAA's interpretation, the BD-5's accident rate is twice that of
the main homebuilt fleet.

Ron Wanttaja



What would be more telling would be the accident rate per hours flown. Even if
the 236 BD-5s were accurate, I suspect the accident per hour would be
significantly higher for the BD5 than your figures indicate. Unfortunately,
there is no available database that would give that information.


Bob Reed
www.kisbuild.r-a-reed-assoc.com (KIS Builders Site)
KIS Cruiser in progress...Slow but steady progress....

"Ladies and Gentlemen, take my advice,
pull down your pants and Slide on the Ice!"
(M.A.S.H. Sidney Freedman)

"RobertR237" wrote in message
...
In article , Ron Wanttaja
writes:


Total homebuilt accident rate: 10%
Total certified BD-5 rate: 21%
Total all-listing BD-5 rate: 8.5%

So whether the BD-5 is twice as bad as the main fleet or a little bit
better really depends on your interpretation of the certification data.
By
the FAA and EAA's interpretation, the BD-5's accident rate is twice that
of
the main homebuilt fleet.

Ron Wanttaja



What would be more telling would be the accident rate per hours flown.
Even if
the 236 BD-5s were accurate, I suspect the accident per hour would be
significantly higher for the BD5 than your figures indicate.
Unfortunately,
there is no available database that would give that information.


I haven't spent that much time looking at the accident reports but it seems
that TTAF and TTE might be listed somewhere on, if not all, a good number of
accident reports. While you wouldn't get a total time for the fleet you
could get a total time for the accident involved fleet. Might be telling.

"Gig Giacona" wrote:

I haven't spent that much time looking at the accident reports but it seems
that TTAF and TTE might be listed somewhere on, if not all, a good number of
accident reports. While you wouldn't get a total time for the fleet you
could get a total time for the accident involved fleet. Might be telling.
+++++++++++++++++++++++++++++++++++

Any body ever see a BD5 flying cross country?
Anybody ever see a BD5 fly?

I'd ask jaun for some figures, but I doubt he
would ever confirm that most flying BD5's have
far less than 50 hours TT on 'em.....
and this would be a lot of taxi time. g

At one time jaun did claimed there was one
with over 350 hours. However, if credibility is
an issue, the figure should be considered bogus.


Barnyard BOb -- over 713 hours TT on my RV3

Yo Bob,

There was a BD-5J that was used as the "Coors Silver Bullet" and then was used
for shows at Oshkosh, etc. I could see that particular BD-5 as having more than
350 hours on it. I don't know if this particular bird is still flying.

After each airshow, the wings were pulled off and it was put in a trailer. Makes
sense as far as having a car and tools at the airshow as well as your plane.

I think a BIG indication of how difficult it is to fly is that a Ex- Blue Angel
was flying it for the demos! There is a gentleman in my EAA chapter that has one
and is rebuilding it after bleeding too much speed and ending up a bit high on
landing. He did mention that he really couldn't see the ground from the almost
fully reclined position that is the pilot seat. His BD-5 uses a Turbomecha
turbine with a PSRU prop reduction for power.

As with all things if it goes hellishly fast it probably doesn't do slow very well.

--
Bart D. Hull

Tempe, Arizona

Check http://www.inficad.com/~bdhull/engine.html
for my Subaru Engine Conversion
Check http://www.inficad.com/~bdhull/fuselage.html
for Tango II I'm building.


- Barnyard BOb - wrote:

"Gig Giacona" wrote:


I haven't spent that much time looking at the accident reports but it seems
that TTAF and TTE might be listed somewhere on, if not all, a good number of
accident reports. While you wouldn't get a total time for the fleet you
could get a total time for the accident involved fleet. Might be telling.

+++++++++++++++++++++++++++++++++++

Any body ever see a BD5 flying cross country?
Anybody ever see a BD5 fly?

I'd ask jaun for some figures, but I doubt he
would ever confirm that most flying BD5's have
far less than 50 hours TT on 'em.....
and this would be a lot of taxi time. g

At one time jaun did claimed there was one
with over 350 hours. However, if credibility is
an issue, the figure should be considered bogus.


Barnyard BOb -- over 713 hours TT on my RV3

On Fri, 14 Nov 2003 16:34:32 -0700, "Bart D. Hull"
wrote:

Yo Bob,

There was a BD-5J that was used as the "Coors Silver Bullet" and then was used
for shows at Oshkosh, etc. I could see that particular BD-5 as having more than
350 hours on it. I don't know if this particular bird is still flying.

Hmmm.
Come to think of it....
I've seen the Coors Silver Bullet fly.
Maybe it has 350 hours, maybe it doesn't...
given the trailering operation.

After each airshow, the wings were pulled off and it was put in a trailer. Makes
sense as far as having a car and tools at the airshow as well as your plane.

By any stretch of the imagination, the
BD5J is hardly an amateur endeavor and
it's value is mostly as an oddity. As you have noted,
it ain't no poor boy or rich boy cross country machine.

I think a BIG indication of how difficult it is to fly is that a Ex- Blue Angel
was flying it for the demos! There is a gentleman in my EAA chapter that has one
and is rebuilding it after bleeding too much speed and ending up a bit high on
landing. He did mention that he really couldn't see the ground from the almost
fully reclined position that is the pilot seat. His BD-5 uses a Turbomecha
turbine with a PSRU prop reduction for power.

I've been told that the "B" wing is NOT at all difficult to fly.

Keeping a liquid cooled engine running without it spewing it's
contents on the inhabitant is but one of the many frightful engine
reliability challenges. Landing out with tiny wheels and NO
crush room rounds out the rest of a very plague ridden machine.

The reclined position is no big deal for any high performance
sailplane jockey.

The BD5 in the hangar next to me does not recline as much
as my old sailplane. This is a beautiful BD5 that is just waiting to
hurt anybody that dares think its untested Kawasaki watercraft
engine is worth risking life and limb in lieu of a proven engine.

As with all things if it goes hellishly fast it probably doesn't do slow very well.

How fast is hellishly fast?
A prop powered SX 300 can do 300...
and actually GO SOMEWHERE.... RELIABILY.

From what I've read about the "B" wing,
it's pretty much of a pussycat with a nice
stall around 65 mph?

For me, the problem is that no proven cost
effective engine exists for this aircraft, and landing
out dead stick is very risky business since you wear
this little rascal without an inch of room to spare.
None for your feet. None for ass. None for your
rib cage. None for your head... and the engine
sits at the back side of it. Hardly engineered
for human longevity in case of emergency.

Barnyard BOb -- over 50 years of successful flight

"Bart D. Hull" wrote ...
There was a BD-5J that was used as the "Coors Silver Bullet" and then was
used
for shows at Oshkosh, etc. I could see that particular BD-5 as having more
than
350 hours on it. I don't know if this particular bird is still flying.

After each airshow, the wings were pulled off and it was put in a trailer.
Makes
sense as far as having a car and tools at the airshow as well as your
plane.

There's a dirty little secret about the Microturbo TRS 18 engine used in the
BD-5J that the owners don't like to talk about. It only gets 50 hours
between hot section overhauls and a hot section overhaul costs $5,000. The
plane is trailered to airshows because the owners don't want to pay the $100
per hour in maintenance costs for the hot section. Well, that and the fact
that the airplane doesn't even have enough fuel for VFR reserves when it
takes off.

Juan's engine, the Microturbo Cougar, on the other hand is a different sort
of animal. It was designed for target drones and has a much lower thrust
rating. Basically it's a disposable engine but if he ever gets it flying
he'll sell it and the airframe to you for $100,000.

Rich

Ron

Tnx for the stats. Validated my gut feeling from seeing scattered
reports through the years.

Of benefit to those thinking about building , if you massaged your
figures to show which birds had the best safety rate, might help some
rethink their possible choice of home built? Of course your gross
figures would include stupidly on pilots part but total percentage
number would still be a good indicator. As chinese say, "Hot airplane
and stupid Pilot, accident make" G

Robert (Borovec) made Crater Lake, OR last night on their way to boat
in FL. They started east through the mountains and with the bad Wx
(ice and snow and cold temp) that came up think they rethought and
moved west to get in the 'Valley' to go south to LA and east into the
dessert and stay south rest of 'voyage' )

Big John


On Fri, 14 Nov 2003 16:04:17 GMT, Ron Wanttaja
wrote:

On Fri, 14 Nov 2003 13:57:03 GMT,
(Corky Scott) wrote:

Man those BD5's just don't seem like a good idea. Tiny, high stall
speed, tight engine compartment, and the pilot sits right on the
bottom of the fuselage.

The airplane has been discussed in this group previously and my
recollection is that it has a very high fatal accident rate. It's
first flight accident rate is also very high. Perhaps Ron Wanttaja
can step in with his always meticulous statistical analysis.

Damn, Corky, were you lurking in the back of the EAA Chapter 26 meeting
last night? I'm in the process of doing a detailed homebuilt accident
analysis, and presented my initial results.

Unfortunately, the year I chose for my in-depth analysis didn't include any
BD-5 crashes, so it's of no use for us in this case. Let's do a simpler
comparison. I ran the NTSB database for the accidents since January 1,
1990:

Total Amateur-Built Accidents: 2881
Total BD-5 Accidents: 22

BD-5s were involved in 0.8% of all homebuilt accidents, and in 1.1% of all
fatal homebuilt accidents. Due to the small size of the sample, this may
not be a significant difference (it's only three accidents extra over 13
years).

Looking at the FATALITY rate:

Total Amateur-Built Fatal Accidents: 837 (# of accidents, not fatalities)
Total BD-5 Fatal Accidents: 9

Homebuilt fatal accident rate: 837/2881, or 29.1%
BD-5 fatal accident rate: 9/22, or 40.1%

But what of the accident ratio in comparison to the size of the homebuilt
fleet? Let me "Back Out" some data that might let us make a comparative
analysis.

The January 2003 FAA database listed 25,886 aircraft as being in the
Experimental Amateur-Built category. The same database has listings for
237 BD-5s, of which 81 are listed as having Experimental Amateur-Built
certification.

Before I go on, allow me to explain the difference. Database listings
include a field for the category the aircraft is certified in. If the
field is blank, the usual process is to assume the airplane has received an
N-number but has not yet been approved for flight. My past analysis
indicates this is not necessarily the case; for instance, John Ammeter's
RV-6 (which flew something like ten years ago) STILL doesn't have an entry
in the Certification block, and, with Juan's help, I uncovered one BD-5
(not one of his, BTW) that made its first flight about five years after
being listed as certified.

Back when I did my first registration analysis, I found about 36,000
aircraft listings with "homebuilt-like" names, but only about 22,000 of
them (this was in 1997) were actually listed as certified. The FAA and EAA
only count those listed as certified, so the published figure is in the
20,000 range instead of in the 30,000s.

So...officially, we should only use the 81 BD-5s for analysis. Due to the
uncertainty, I'll list the figures for the full fleet as well. BTW, I used
"BD-5", "BD 5", "BD5", and "BEDE 5" (with appropriate wild cards) as my
search terms.

Anyway, to the stats:

Total homebuilts in 2003: 25886
Total certified BD-5s: 81
Total listed BD-5s: 237

Lets compare the number of accidents over the past 13 years with the
current number of homebuilts. We'll add the accident airplanes back into
the current fleet for a baseline.

This doesn't, in itself, produce a viable statistic. But it is useful in
comparing between aircraft types.

Total homebuilts plus accidents: 28767
Total certified BD-5s plus accidents: 103
Total listed BD-5s plus accidents: 259

(Note that the NTSB accident listings make no differentiation whether the
accident aircraft had a blank in the certification status field)

Percentages:

Total homebuilt accident rate: 10%
Total certified BD-5 rate: 21%
Total all-listing BD-5 rate: 8.5%

So whether the BD-5 is twice as bad as the main fleet or a little bit
better really depends on your interpretation of the certification data. By
the FAA and EAA's interpretation, the BD-5's accident rate is twice that of
the main homebuilt fleet.

Ron Wanttaja

[Answering two postings in one message]

On Fri, 14 Nov 2003 09:59:19 -0600, Big John wrote:

Ron

Tnx for the stats. Validated my gut feeling from seeing scattered
reports through the years.

I did a quick scan of the BD-5 accident reports. Due to my recent analysis
work, I'm a bit attuned...it seemed to me that the BD-5 had a higher
percentage of "Builder Error" accidents than I was used to seeing, and
lower pilot error. This may be a function of people buying kits on the
cheap and trying to finish them; it might be a function of the aircraft not
having a "standard" power package. I may take an in-depth slice at the
BD-5s and compare them to the Fly Baby, whose accident reports I already
have.

Still, though, the actual number of cases make a pretty small statistical
sample.

Of benefit to those thinking about building , if you massaged your
figures to show which birds had the best safety rate, might help some
rethink their possible choice of home built? Of course your gross
figures would include stupidly on pilots part but total percentage
number would still be a good indicator.

Had that experience at EAA last night. I presented a list of the airplanes
that had the highest rate (I used a criteria of having a minimum of 5
accidents in that year), and one of the guys had been interested in that
design. But when we looked at the individual reports, nothing really stood
out. Mostly pilot error, one pilot incapacitation (!). Nothing in common,
in any of the accidents, that one could point at as indicating there was
something wrong with the design. And it was an amphibian, which gave more
opportunity for problems (e.g., hitting a sunken log...).

In another example, there were two similar aircraft produced by opposing
companies. Similar fleet sizes on the registration database, but one type
had five accidents and the other had nine (in a single year). Almost
identical designs, the same engine(s).

So I'm not sure how useful the by-aircraft rates are. Fun to look at,
though.

On Fri, 14 Nov 2003 16:23:27 -0600, - Barnyard BOb wrote:

] Any body ever see a BD5 flying cross country?
] Anybody ever see a BD5 fly?

Actually, other than at fly-ins, I actually see very few of ANY homebuilts
other than the ones based at my home field. I don't think I've ever been
at an airport when a Lancair dropped in, nor a Wheeler, nor a Venture, nor
a Rotorway Exec, nor a Rans, nor a Pietenpol, or dozens of other common
homebuilts. Maybe I just don't get out much. :-)

But when you think about it, about one in ten small aircraft you see should
be a homebuilt. Doesn't seem that way. Probably because of all those 152s
and 172s with students flying 'round and 'round.

Ron Wanttaja