Preliminary report on F-1 accident
James & Shalise Cash
there was an F-1 Rocket crash in Houston, several weeks ago. An eyewitness
saw the aircraft impact the ground near vertical, at a high rate of speed.
The vertical stabilizer tumbled down moments later. This is Mark
Frederick's preliminary finding after talking to the FAA, NTSB, and viewing
the wreckage.
Jimmy
PRELIMINARY REPORT
CREEKMORE F1 ACCIDENT
Hi All:
I'm sure you have been waiting for some definitive data regarding Tom
Creekmore's accident. I was able to inspect the wreckage of the aft section
of the ship last Friday, along with the FAA. The following is my report to
you, not an official NTSB report.
Preliminary Results are as follows:
The builders did not fabricate nor install the upper attachment fitting for
the V Fin aft spar. This is a length of 1x1x.125 6061T6 angle that is
designed to absorb the Fin torque loads resulting from rudder deflections.
Four AN3 fasteners attach this fitting to the aft section of the fuselage,
and to the V Fin aft spar.
Lack of this fitting caused the HS-015 to absorb most of the Fin torque
loads, in addition to flexing the HS-015 past its fatigue life. It appears
that the HS-015 failed at one of the V Fin spar attach bolts, and separated
from the H Stab spar.
In addition, the V Fin fwd spar/HS-015 attach holes were not drilled per the
assy manual, with one hole appearing to have about 3/16" ED on the HS-015
(3/8" would be a standard distance). The separation at the HS-015 appears to
have started at this hole.
I will wait for the NTSB to publish their findings, and I'll add this to a
dedicated web page detailing what happened.
Regards,
Mark
Dennis O'Connor
Makes my stomach go hollow just to read about the missing bracket...
Denny -
RV7 - building and I fabricated the Vstab spar bracket just a few weeks
ago...
"James & Shalise Cash" <jc...@charter.net> wrote in message
news:v1jq4k3...@corp.supernews.com...
Dillon Pyron
<doco...@chartermi.net> wrote:
>Thank you for the heads up...
>Makes my stomach go hollow just to read about the missing bracket...
>
>Denny -
>RV7 - building and I fabricated the Vstab spar bracket just a few weeks
>ago...
I'm still in the "data acquisition" mode, but this sort of thing gives
me the willies.
10pm: I'll do that tomorrow.
Tomorrow is three weeks later, and you turned the page sometime in the
previous 21 days.
I hope everyone building takes an afternoon and puts a second
checkmark by every step you've done so far. I'd rather refer to
everybody in the present tense, even the PITAs.
dillon
Dave Hyde
> I'm still in the "data acquisition" mode, but this sort of thing gives
> me the willies.
It gives me 'the willies' too, but probably for different
reasons.
1) The bracket as described sounds similar to that on the
RV-4. If so, it's not a 'make once and forget' part, as
it ties into both the fuselage and the vertical stab...I
can't fathom how one could leave it out altogether.
2) I'm uncomfortable with a manufacturer releasing
such a damning cause to the public before the NTSB
has concluded their investigation. We only have
part of the story here.
Dave 'first one to the chalkboard wins the dogfight' Hyde
na...@brick.net
Kyle Boatright
My thoughts were that the kit supplier was "doing the right thing" by
posting critical information ASAP as a reminder to other F1 builders (and RV
builders, for that matter) not to leave out this brace.
Of course, it is also good for the kit seller if the conclusion is that the
airplane was incorrectly built rather than improperly designed.
KB
"Dave Hyde" <na...@brick.net> wrote in message
news:3E1B8C55...@brick.net...
Ed Wischmeyer
> > such a damning cause to the public before the NTSB
> > has concluded their investigation. We only have
> > part of the story here.
Mixed feelings on this one. There have been tons of accidents where the
real causes were not at all obvious, and considerable effort was
required to find out what went wrong. On the other hand, when there's
something so obvious and so compelling as a major piece not fabricated,
why not release that fact/observation/opinion right away? There will
likely be other facts later, but what good does it do to sit on that information?
Ed Wischmeyer
David Rahman
then its the end of that story.
David
Ed Wischmeyer wrote:
> ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> Name: edwisch.vcf
> edwisch.vcf Type: VCard (text/x-vcard)
> Encoding: 7bit
> Description: Card for Ed Wischmeyer
James & Shalise Cash
> such a damning cause to the public before the NTSB
> has concluded their investigation. We only have
> part of the story here.
>
> Dave 'first one to the chalkboard wins the dogfight' Hyde
> na...@brick.net
The entire F-1 building community is asking Team Rocket questions (not to
mention the RV's with a similar design). After inspecting the wreckage,
let's run thought the logical options and outcomes to see what makes sense:
1. Share observations with builders, to prevent a similar accident from
occurring in the future. I think Team Rocket felt that it was important to
share with it's customers the possibility that this accident may have
occurred do to deviations from the design (i.e. missing bracket), and that
all builders should check and double check their work. This can only have a
positive benefit to the builders, even if the NTSB comes up with a different
finding.
2. Keep observations a secret until the NTSB releases it's findings months
from now. As a supplier/supporter of this kit, keeping vital information
secret would seem irresponsible.
3. Create a lie about missing parts in the tail, to blame the builder and
divert attention from a design deficiency. Hmmmmm, that might work until
the NTSB releases it's findings and states the parts were not missing.
Creating such disinformation may not only be civil negligence, but also
criminal.
As a customer of any product, I would expect a responsible supplier to
choose option #1. I would be extremely upset if I found that the supplier
sat on important information that he could have released immediately. Just
my humble opinion.
Jimmy
Ron Wanttaja
<jc...@charter.net> wrote:
>The entire F-1 building community is asking Team Rocket questions (not to
>mention the RV's with a similar design). After inspecting the wreckage,
>let's run thought the logical options and outcomes to see what makes sense:
<Snipped for brevity>
Sound logic, Jimmy, and I can't really fault you. However, there are
dangers with early data release.
About four years ago, a Fly Baby shed its wings. While the pilot was
wearing a parachute and successfully bailed out, we in the Fly Baby world
were of course concerned. In forty years, the Fly Baby has had a fairly
large share of wing-failure accidents (12 out of fifty listings in the NTSB
report) and we were eager to find out if a new failure mode had been found.
I talked to the FAA that performed the initial investigation, and he
commented that the wing-attach plates didn't seem to have enough edge
margin. I, of course, leapt to send the word out to Fly Baby owners that
this accident probably was related to workmanship.
The problem was, the FAA guy was wrong. The cause of the failure was not
insufficient edge margin, but vibration cracking. The problem was not
workmanship, but the use of non-standard solid bracing wires that
transmitted too much vibration to OTHER parts of the bracing system.
(see http://www.wanttaja.com/flybaby/hinton.htm)
Certainly, warning people to watch their edge margin wasn't a bad thing to
do, but it really didn't have much to do with this particular accident.
A year later, another 'Baby shed its wings (this one fatal), and, again, I
was told information that seemed to wrap it up simply (aircraft missing
thimbles from flying wires). This time, I sat on it. And, again, the
actual cause was something far different.
I guess I don't fault getting the early word out. But everybody has to
understand that the data is tentative....
Ron Wanttaja