had an "iteresting" L2 certification flight, a PML Endeavor on a J350.
It went up about 100 ft, and then went off at an angle. It continued
up, arced over and started down, and down, and down. When the
parachute finally came out, most people thought it would be damaged,
but it was found in perfect shape about half a mile away.
Ready to take off:
http://members.aol.com/jimn469897/smoke.jpg
Missed most of the rocket, but you can see the J350 in action:
http://members.aol.com/jimn469897/fire.jpg
Safely back on the ground:
Should be "L2 failure". Part of the cert is a "safe flight" and this
clearly didn't fit the bill.
Who signed your cert?
Has certification sunk this low? A clearly bad flight and it's a "success"?
Damn.. No wonder the BATFE wants to over-regulate us! The cert team here
showed the brain power of a slug!
Really? Was it a perfect flight? By no means. Was it a 'safe'
flight? It certainly appears that way, based on both the description
and the pictures. Firstly, there was no indication of what the 'angle'
was. Secondly, if the angle was sufficent that the ejection charge did,
indeed, deploy the recovery system in a safe manner, then the individual
performed a safe flight.
He certainly had one that was close to the margins -- and got very
lucky. If the rocket wasn't stable, it wouldn't have ejected the
recovery system in time. If it was too much of an angle, it wouldn't
have ejected in time. If the ejection charge was too long, the rocket
would have been damaged. If the angle was such that there was a
dangerous situation, it appears that would have been discussed.
There's no indication as to what went wrong with the flight to cause it
to cock after a 100' initial flight -- it might be a bad reload, or
improper assembly, or any of a number of other things. However, if it
wasn't a bent/cracked fin (which would have disqualified the
certification since the model would not be ready to fly again), then
according to the certification procedures, this was a valid flight.
The procedures have been hashed out over a period of time. As indicated
above, they don't require a 'perfect' flight, but a 'safe' flight. All
indications are that this flight was 'safe'.
I have to admit that if I'd been doing the certification, I would have
been going over the rocket with a fine-tooth comb to find any damage,
and attempting to discover if there was a motor or assembly failure, but
that information wasn't provided here. Given the information provided,
this was a (borderline) safe certification flight.
This isn't any different than someone passing their driving test with a
70% (presuming that's the minimum passing grade). Would I want to drive
with that person, or am I thrilled that they're on the road? No, but
the line is drawn at a point, and that's where it is. The same is true
for HPR certification -- he got lucky that everything worked, but the
point is that the safety margins ALLOWED it to work.
This reminds me of the old joke about what do they call the guy who
graduates last in his class at medical school...
They call him "Doctor".
David Erbas-White
David Erbas-White wrote:
One minor addendum...
If the person signing off on the certification had chosen not to do so,
I would have supported that decision, because AFAIK that person has the
final say, period. My point was that according to the description of
the flight and the rules, that 'should' be ruled a safe flight -- but
the certifying person does have the 'final say'.
If you disagree with that assessment, then the rules need to be changed
-- for example, a rule that initial ejection should occur within 2
seconds of apogee, or something similar. Barring that, the flight
appears to have conformed to the rules, as stated.
David Erbas-White
The rocket landed safley in a field a half mile from the nearest
person. I have no idea how anyone could consider that unsafe. An
angle could be anyting from 1 degree to 179 degrees. A number of other
rockets went off at a similar angle, none of them came anywhere near
the spectators. If the flight was unsafe, I would not have presented
it for certification, and if i had it would not have been certified.
There was absolutly no talk of not certifying the flight. Except for
some residue and dirt, it is impssible to tell that the rocket has even
been flown.
Congrats on the cert, Jim. Don't let the Monday Morning Quarterback get
you down. It seems to be a rule of rmr that any post about a cert
flight that even hints at anything remotely out of the ordinary will
generate responses condemning the flyer, the person who signed the
cert, the cert process, the national org, the local club, the RSO, etc.
-- and predictions of the downfall of Rocketry As We Know It.
¿
Probably if the rocket had gone over people with that flight profile,
most would be saying it was an unsafe slight. I think the question is
would you have considered it unsafe if that had happened? If so, it
should not be considered sucessful. When something malfunctions as in
the case being discussed, the direction it will go is unpredictable.
A good flight is a good flight no matter where it goes.
Phil Stein
Hi,
Would be curious if the next flight is routine. That would point to
the particular motor being the issue. Everyone should lighten up as the
flight did turn out successful for Jim, the field looked like it was
wide open and he did say there were no spectators near the model.
How many folks would confess to flight failures after achieving
certification? I mean one can certify and then go out and experiment
and if the area is isolated the danger is minimized. I sure as heck
wouldn't spend a bunch of time and money on a model to see it crash.
Trying to pimp the guy to look for a "hairline" fin crack is inappropriate.
Kurt Savegnago
Jim,
Congratulations on your cert flight. Don't worry about what other people
say. A very small portion of the folks that frequent here want to criticize
everything. It gives them the illusion of power and superiority.
I know on my cert flights all of my rockets went off a straight vertical
flight pattern. I think it was called apogee :-)
Andrew
It's crap like this that really makes me wonder who should be able to sign
off on a cert. (I checked out your links) You could drop your bird from
100' without a chute on to the grass field you used and not have any damage!
Your cert was a failure, and if you want to take pride in it, I can't stop
you, but any reasonable cert team would have laughed you off the field if
you claimed a "good flight" for this. You got your merit badge, but you
didn't earn it...
(former NAR section advisor and TRA Prefect - currently just TRA L3)
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http://members.aol.com/jimn469897/smoke.jpg
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http://members.aol.com/jimn469897/ground1.jpg
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