accident in Knoxville, IA

Please understand I wasn't there and am not being critical of the pilots decisions.

I often spend time with students trying to learn from others misfortune and reinforce my somewhat extensive safety precautions.

I feel it is best to only fly passengers with a properly running gyroplane.
The continuing challenges with the engine would have restricted me to flying the pattern solo until I had the issues resolved.

Part of becoming familiar with an airport is to look for emergency landing spots and identify obstructions (wires in this case).

At 500 feet agl I can glide 1,500 feet to find a suitable emergency landing zone. The runway at OXV is 75 feet wide and 4,000 feet long. There are lots of open fields at the departure end of runway 15.
https://www.google.com/maps/@41.2984.../data=!3m1!1e3

I assume the engine is going to go quiet on every takeoff and prepare for that.

I do not need to check the altimeter to see that I am descending.

Part of the takeoff procedure is to make note of the rate of climb with the vertical speed indicator.

I suspect earlier recognition of the problem would have allowed them to return to the airport.

I feel flying closed traffic the pattern should always be within gliding distance of the runway.

Before I leave the runway environment I check that the temperatures and pressures are in the green.

I suspect the engine tachometer and manifold pressure gage provided information that the engine was not at takeoff power long before they left the runway environment.

I wasn't there so I don't know what other challenges existed.

These are just some thoughts to perhaps make your takeoff procedures safer.
 
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Yes it was last year Don Randle.

The factual report was recently issued.
 
When turbocharging an engine you can gain 7% in HP for every 1 lb of boost,a intercooler is not needed with only 5-6 lbs of boost,

The more pressure that's put on the engine the less reliable it becomes,there is a breaking point for reilabllity Vs HP gain.

A little 1200 cc engine will have smaller/weaker parts,ie the crankshaft.rods ,pistons and valve train.I would think that much HP is

taking it to its limits.

Also turbocharging an engine with carbs is a really bad idea to me.The carbs would have to be designed to work with external

air pressure applied to them as opposed to pulling a vacuum to operate them properly.
 
The 912 ULS is a 1352 cc engine. The 914 is 1211 cc, basically, a turbo'd 912 UL. All three use the same pressed crank which seems to be a weak link, especially for those with upped power. Not a huge point here, just clarification.
 
magknight;n1132765 said:
The 912 ULS is a 1352 cc engine. The 914 is 1211 cc, basically, a turbo'd 912 UL. All three use the same pressed crank which seems to be a weak link, especially for those with upped power. Not a huge point here, just clarification.

A point of note is that Rotax pushes that crankshaft only to 115hp in the 914. Not to the 135 hp that Xenon pushes it to.
When they decided to go to make the 915 at 135hp, they redesigned the whole thing and went to fuel injection to eliminate the Carbs running on turbo boost issue.
 
Up to 125 HP the crank should be able to handle with reserve for safety a bit. 135 HP IMO requires welding and rebalancing the crank.
915iS is not ready for fixed pitch prop or ground adjustable prop. The whole mapping in the ECU is done for a constant speed prop. There is a single lever operation constant speed prop being developed by MT prop from Germany using a Searey Technology Demobstrator here and I have had extensive hours long conversation with the engineer helping do it.
Min about 6 months time Rotax plans to have an ECU mapping appropriate for a ground adjustable or fixed pitch prop done. Instead of getting 141 full HP,we may see only 135 hp out of it
 
Glad they walked away from that one.
Vance made several valid critical points.
A gyro engine out from 500' AGL over pastures shouldn't result in a wrecked machine.
Lots to learn from this incident.


______
Please understand I wasn't there and am not being critical of the pilots decisions.

A woman I knew had a little boy who hadn't much nuance in his interpersonal communication, and would often blurt out rude things to people.
So, she taught him to say, "I don't mean to be rude, but ______." He would reliably preface with that, and then say the same rude thing, lol.

When Vance pointed out that the pilot shouldn't have flown with a passenger with a funky engine problem, didn't early enough discern his looming trouble,
apparently didn't know he was descending until he saw his VSI, and missed ample safe landing spots south of Runway 15, etc., it is patently criticizing the pilot's decisions.

I've done so many times on the forum. We generally hope to criticize in an empathetic and helpful way.
But let's simply call criticism for what it is, vs. trying to couch it in transparently pious terms and thus allege that we aren't criticizing at all.
It comes across to me as phony.

Thanks,
Kolibri
 
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Kolibri;n1134905 said:
Glad they walked away from that one.
Vance made several valid critical points.
A gyro engine out from 500' AGL over pastures shouldn't result in a wrecked machine.
Lots to learn from this incident.


______


A woman I knew had a little boy who hadn't much nuance in his interpersonal communication, and would often blurt out rude things to people.
So, she taught him to say, "I don't mean to be rude, but ______." He would reliably preface with that, and then say the same rude thing, lol.

When Vance pointed out that the pilot shouldn't have flown with a passenger with a funky engine problem, didn't early enough discern his looming trouble,
apparently didn't know he was descending until he saw his VSI, and missed ample safe landing spots south of Runway 15, etc., it is patently criticizing the pilot's decisions.

I've done so many times on the forum. We generally hope to criticize in an empathetic and helpful way.
But let's simply call criticism for what it is, vs. trying to couch it in transparently pious terms and thus allege that we aren't criticizing at all.
It comes across to me as phony.

Thanks,
Kolibri

I have studied enough accidents and been in enough difficult situations that I would never imagine that I knew what was in the mind of someone where something didn’t work out.

I don’t know what should have been done or why the pilot did what he did.

I feel any emergency landing in any aircraft is a challenging situation and I would not suggest I could have done it better.

I will say where I suspect things went amiss and try to identify the accident chain.

I feel there is value in the thought process even I am wrong.

The Pilot is not my client and it is not my job to teach him how I think.
 
Kolibri,
Vance was polite and showed restraint in my opinion. Did you read the report? Read pages 4 and 5 please. They had engine problems for the last 37 hours of flying.

Let me summarized the report facts that jump out at me at the risk of being rude:

- Built to 51% rule in four 12 hour days - really?
- No annual recorded in the log book after 300 + hours on the aircraft.
- Neither of the two brothers knew what the "turbo" knob function did but their excuse is that they never got a book for the turbo kit. The dealer also stated that the manufacturer didn't provide any instructions for the turbo kit to the dealer.
- claimed that it had run flawlessly for 37 hours after changing floats but go on to talk about repeated manifold probe problems

I am sorry but any pilot who BUILDS an experimental aircraft and doesn't know every nut, bolt, switch, and knob function is not taking his life or the life of other souls on board seriously. I think the pilot did well to put it down but the signs were there to stop flying it and haul it 100 miles back to the dealer! Put me in the rude camp too.
 
I don’t know what should have been done . . .
I feel any emergency landing in any aircraft is a challenging situation and I would not suggest I could have done it better.

That's not what came through to me about your criticism, a criticism by the way that I wasn't objecting to.
I objected only to its "I'm not judging the pilot" qualifier which rang false to me.

Of course you knew what should have been done . . . you enunciated very clearly several undone/poorly done items.
And, you certainly implied that one c/should have landed better. (Partial power from 500' AGL above pastures? What's the big deal?)
They should have known safe paths after takeoff from their own airport, as you pointed out. I agree.

Look, they screwed up on many levels. It's not wrong, or evil, or sh*tty to simply say so.
Criticism was indeed called for. When it is, let's not whitewash that we're not being critical. This is all I meant.

_____
HighAltitude, my point was not that criticism ("rudeness") was wrong, or avoidable.
Sometimes it's necessary. Be polite, of course, but don't feign that it's noncritical.

Regards,
Kolibri
 
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Kolibri;n1134913 said:
That's not what came through to me about your criticism, a criticism by the way that I wasn't objecting to.
I objected only to its "I'm not judging the pilot" qualifier which rang false to me.

Of course you knew what should have been done . . . you enunciated very clearly several undone/poorly done items.
And, you certainly implied that one c/should have landed better. (Partial power from 500' AGL above pastures? What's the big deal?)
They should have known safe paths after takeoff from their own airport, as you pointed out. I agree.

Look, they screwed up on many levels. It's not wrong, or evil, or sh*tty to simply say so.
Criticism was indeed called for. When it is, let's not whitewash that we're not being critical. This is all I meant.

_____
HighAltitude, my point was not that criticism ("rudeness") was wrong, or avoidable.
Sometimes it's necessary. Be polite, of course, but don't feign that it's noncritical.

Regards,
Kolibri

I have no control of what you read into the things a write and I don't want to diminish the learning opportunity here by pretending to know it all.

If you imagine you would not make these errors in my opinion you are being dishonest with yourself and missing a learning opportunity.

I don't know what was in the field or why the landing didn't work out and neither do you. I feel your question; "What was the big deal?" showcases your ignorance and inexperience.

When I had my last FAA check ride for my class two medical statement of demonstrated ability he didn't have me actually land in the fields because despite what you imagine that would be dangerous. He wanted to see if despite my monocular vision I had the knowledge and skill to set up an emergency landing. We did the engine at idle to the ground over the runway to SIMULATE an emergency landing to test my skills.

Pilots with more skill and experience than I have put together accident chains and I suspect they were able to justify each decision in their mind.

I have put together accident chains and was saved by luck from the consequences of my errors. One day my luck may run out.

In my opinion your unwillingness to recognize your own poor decisions makes it harder for you to learn and grow.

I feel imagining you would never do anything that stupid and you have the skills to make every emergency landing work out limits your ability to learn from accident reports and your own experiences.

I hope pilots here will learn from thinking about this accident openly and honestly and will not be sidetracked by your desire to make others appear wrong.

There are links of this accident chain that I would have done differently; that does not make me right or the accident pilot wrong.
 
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If you imagine you would not make these errors in my opinion you are being dishonest with yourself and missing a learning opportunity.
I would not have made those errors. Neither would you have, because you clearly called out what you would have done that they did not.

. . . and will not be sidetracked by your desire to make others appear wrong.
There are links of this accident chain that I would have done differently; that does not make me right or the accident pilot wrong.
Oh, so they were not wrong?
And you'd have made their same mistakes? C'mon.

You pointed out their errors, and implied that you wouldn't have made them. Fine. I agreed.
I wouldn't have made them either. Perhaps others, but not those.

If you're going to be critical and judge, then at least don't try to allege that it's something else than that.



In my opinion your unwillingness to recognize your own poor decisions makes it harder for you to learn and grow.

I feel imagining you would never do anything that stupid and you have the skills to make every emergency landing work out limits your ability to learn from accident reports and your own experiences.
Vance, feel free to quote me on such an attitude, or even point out a fair implication of such.
I have indeed made poor decisions. We all have. I try to scrupulously learn from mine, with personal after-action accounts that I write for myself.

Once, only a few miles away from an airport with <1000' ceilings on an SVFR approach, the overcast quickly lowered and began to shrink about me.
I had only a couple of minutes to pick out a pasture below me that hadn't cattle, was long enough to land and takeoff from, and oriented favorably towards the wind.
I found one, drug the field at 200', and then landed. This was in a FW. An hour later, ceilings had lifted enough for me to takeoff and land at the nearby airport.
I wrote a report about it later for myself. I did many things right (primarily keeping my cool, and greasing a near-stall landing), and a few things wrong (such as chancing a SVFR approach).

So, you're welcome to FINALLY cease imagining what I think, and stop projecting on to me thought processes I don't have.


Thanks,
Kolibri
 
Kolibri;n1134934 said:
I would not have made those errors. Neither would you have, because you clearly called out what you would have done that they did not.


Oh, so they were not wrong?
And you'd have made their same mistakes? C'mon.

You pointed out their errors, and implied that you wouldn't have made them. Fine. I agreed.
I wouldn't have made them either. Perhaps others, but not those.

If you're going to be critical and judge, then at least don't try to allege that it's something else than that.




Vance, feel free to quote me on such an attitude, or even point out a fair implication of such.
I have indeed made poor decisions. We all have. I try to scrupulously learn from mine, with personal after-action accounts that I write for myself.

Once, only a few miles away from an airport with <1000' ceilings on an SVFR approach, the overcast quickly lowered and began to shrink about me.
I had only a couple of minutes to pick out a pasture below me that hadn't cattle, was long enough to land and takeoff from, and oriented favorably towards the wind.
I found one, drug the field at 200', and then landed. This was in a FW. An hour later, ceilings had lifted enough for me to takeoff and land at the nearby airport.
I wrote a report about it later for myself. I did many things right (primarily keeping my cool, and greasing a near-stall landing), and a few things wrong (such as chancing a SVFR approach).

So, you're welcome to FINALLY cease imagining what I think, and stop projecting on to me thought processes I don't have.


Thanks,
Kolibri

I have no desire to discuss this further with you.

I am not interested in what you imagined I wrote and I feel your attitude prevents you from learning so there is no point in continuing.
 
At 500 feet agl I can glide 1,500 feet to find a suitable emergency landing zone.
The runway at OXV is 75 feet wide and 4,000 feet long.
There are lots of open fields at the departure end of runway 15.
https://www.google.com/maps/@41.2984.../data=!3m1!1e3


OVX.png


Please understand I . . . am not being critical of the pilots decisions.
So, posting a link to GoogleMaps of OXV and mentioning that "there are lots of open fields at the departure end of runway 15"
is an example of "not being critical of the pilots decisions"? Yeah, sure.


_________
I have no desire to discuss this further with you.
I am not interested in what you imagined I wrote and I feel your attitude prevents you from learning so there is no point in continuing.

Great, suits me!

Psychological projection is a theory in psychology in which humans defend themselves against their own unconscious impulses or qualities
(both positive and negative) by denying their existence in themselves while attributing them to others.
 
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The pilot taxied to the end of the runway and did a full-length departure. He stated that the
taxi, runup, takeoff, and climb to 500 ft above ground level (agl) were normal. The engine was
running fine. He had planned to climb to 1,000 ft agl, circle around, and come back to the
airport. However, while continuing to climb through about 500 ft agl, the gyroplane stopped
climbing and started to descend. He didn't remember hearing any change to the sound of the
engine and he thought the engine was still running, but he was aware that the gyroplane wasn't
climbing anymore. He checked the altimeter and confirmed that they were in a descent. He
started to turn back to the airport but realized he couldn't make it back and tried to land in a
field. He saw that he would not clear the powerlines, so he turned sharply, but the gyroplane
hit the powerline and crashed on the side of the ditch. He turned the engine and fuel off and he
and the passenger climbed out the aircraft. A small grass fire had started in the ditch by the
fallen powerline about 20 yards from the gyroplane and it was quickly extinguished; it did not
affect the gyroplane wreckage.

The pilot rated passenger reported that the takeoff was uneventful. He stated that during the
initial climb [i.e., from 500' AGL to 1000'], he heard a change in the sound of the engine, like a decrease in engine RPMs. The
pilot told him that they were losing power as he was attempting to troubleshoot the problem.
The pilot turned to an open field to the right side of the gyroplane but was unable to avoid
hitting the powerline. He reported that it was about 10 to 15 seconds from the time of the loss
of power until impact.
The accident site was located about 800 ft south of the departure end of
runway 15.

https://app.ntsb.gov/pdfgenerator/Re...Final&IType=LA

I realize that time estimation under stress can be inaccurate, but to have crashed from 500' AGL in 10-15 seconds
means a descent of 2000-3000fpm. A power-off descent in level attitude would be around 1100fpm, so they apparently
had some downward pitch.

They probably wish they'd stayed in the pattern vs. flying south of the runway. An emergency landing from 500' AGL pattern
would have likely been mostly drama free. Whenever I do any significant work on my gyro, my initial flying is several laps
around the pattern just in case anything feels weird or quits on me.

Once, I'd installed the carb throttle return spring in the wrong location from memory (and was suspicious of it), and it stuck on WOT
after takeoff. I realized at once why, set up for a short final, and killed power for my first unplanned dead-stick landing. (Another
way to have handled it was to descend with excessive pitch, hanging on the prop until touchdown, and then killing power.)

An early CFI had me do a power-off spiraling descent over the runway from about 1000' AGL, and then land. Very instructive.
I.e., in a gyro one can land within a very small footprint from directly above, if necessary. Coming from FW, it's a different sensation.

Anyway, I'm glad they both walked away from that one. Going through a power line, it could have been horrific.

One good thing they did was to use a full-length departure. Intersection departures are tempting in a gyro or other STOL aircraft,
but, as they say, runway behind you on a takeoff roll is useless. A gyro engine-out over a long runway can often be a non-event.

Regards,
Kolibri
 
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If I the engine goes quiet in The Predator I plan a three to one glide ratio. In other words 500 feet I have a circle with a radius of 1,500 feet that I can reach to touch down. A wind can shorten this dramatically.

It is my observation wires are not at ground level and depending on the wires may be as high as 200 feet above the ground in flat terrain, higher across a canyon.

I am always looking for places to land and noting the locations of obstructions. As I fly out or a place more often I work on creating a clear mental picture of the wires, trees, fences and ditches.

Some wires are very hard to see and I find it best to look for the poles and fly over them if I need to cross the wires.
 
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