V-Twin Down Janesville

[QUOTE="

With gear down (like this one), climb performance is impacted. I obviously don't know this plane, but compared to the 160 and 180hp V-twins, I would expect this 190hp version to climb at least 300-400fpm with full fuel and two people.[/QUOTE]

We’re finding little climb on one engine with gear down. We’ve also had to come back and land on one motor twice because of inflight failure of the Hartzell starters when testing shutdown and feathering. This happened on both sides.
 
Unfortunately the links from the Carol system are not static. Here's the report.
You can also get it along with the docket by searching in Carol for CEN21FA130.

Nauga,
and the missing link
 

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nauga said:
Unfortunately the links from the Carol system are not static. Here's the report.
You can also get it along with the docket by searching in Carol for CEN21FA130.

Nauga,
and the missing link
Click to expand...
So very odd that a co-pilot was "authorized".
 
Kenny Phillips said:
So very odd that a co-pilot was "authorized".
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The special flight permit limited occupancy to 'essential flight crew' then explicitly authorized a 'co-pilot,' probably because it was requested as such and the airplane was single-pilot.

Nauga,
who doesn't get what he wants without asking.
 
Read it and the docket the other day.

Not sure what to say, somewhat of a mess all around. Such a shame.
 
Kenny Phillips said:
So very odd that a co-pilot was "authorized".
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I think it would be because they were both there with the airplane away from home, both pilots, so the FAA decided to let them Ferry with a passenger so to speak. Using the term co-pilot seems like a reasonable enough thing to do even though it’s not a plane that requires a co-pilot. Seeing the request for the Ferry Permit would answer the question, but I doubt we will. Maybe there was another legitimate reason to have two pilots on board
 
mandm said:
What’s the verdict?
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If I read the report right, a faulty instrument indication caused the pilot to shut down (or feather) the operating engine. The prop on the good engine was damaged by a gear door that broke off from apparently flying too long at Vle.
 
mandm said:
What’s the verdict?
Click to expand...

Wire to oil pressure sending unit on left engine broke. Display showed a red "X" over the oil pressure. Pilot assumed this meant no oil pressure and shut down the engine. The right main main gear door then departed and went through the right prop. The previous flight from Appleton was flown 30-50kts above vLE. That probably weakened the gear door mounts. There were also drugs present in the toxicology report in the PIC. No idea if they were a factor.

So I guess the verdict is:
1) Know the systems of the airplane you're flying. On that system, zero oil pressure is indicated with a "0" and most likely an alarm (at least that's how I configured mine). Lost connectivity with the sensor is displayed with an "X" over the readout for that sensor.
2) Don't exceed the limiting V speeds. They are there for a reason. In this case, had they just stayed below 140kts they would have landed (on one engine) discovered the oil pressure sensor wire was broken, had it fixed and continued on their way.
 
Another point. In your oil gauge suddenly reads 0 oil pressure, the engine is almost certainly toast before you can do anything.
Therefore, take your time and verify before shutting down the engine.

Tim
 
donjohnston said:
So I guess the verdict is:
1) Know the systems of the airplane you're flying. On that system, zero oil pressure is indicated with a "0" and most likely an alarm (at least that's how I configured mine). Lost connectivity with the sensor is displayed with an "X" over the readout for that sensor.
2) Don't exceed the limiting V speeds. They are there for a reason. In this case, had they just stayed below 140kts they would have landed (on one engine) discovered the oil pressure sensor wire was broken, had it fixed and continued on their way.
Click to expand...
3) Don't pass up a good runway.

Just sayin'...
 
tspear said:
Another point. In your oil gauge suddenly reads 0 oil pressure, the engine is almost certainly toast before you can do anything.
Therefore, take your time and verify before shutting down the engine.
Click to expand...
You could also see if oil temp is rising...
 
This is the reason they do investigations. Without the data, it looked a lot like fuel contamination. With the data, looks like a perfectly good engine was shut down. This makes it even more sad. Hindsight being 20/20, retract the gear even though your permit requires it to stay down, and don't shut down the engine.
 
Not saying it contributed to the accident in any way but was anyone else shocked to read the left seat pilot had amphetamines in her system?? Wasn't she a career pilot and also in the guard? Seems like a massive risk to be taking drugs like that knowing you could get tested at any point... and I don't believe you can be flying on any prescription amphetamines... just wow. Again - not saying this caused the accident it just caught me by surprise.
 
srp_4737 said:
Not saying it contributed to the accident in any way but was anyone else shocked to read the left seat pilot had amphetamines in her system?? Wasn't she a career pilot and also in the guard?
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DoD prescribes amphetamines and barbiturates for their pilots. They also ground test you with those same meds.

ETA: the docket shows the co-pilot tox report is where the medication was found. Looks like wellbutrin, which can cause a false positive for amphetamine in urine tests. Don’t know if that’s the same for blood tox screens.
 
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dtuuri said:
You could also see if oil temp is rising...
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be aware that it requires oil circulating in the system to make the Oil Temp gauge rise !

old story / warning from my racecar days: (liquid cooled engines)

If your engine temp gauge suddenly goes _down_ while racing, that (usually) means you’ve lost your coolant because there’s no longer any hot coolant bringing heat from the engine to the sensor.
 
ChopAndDrop said:
be aware that it requires oil circulating in the system to make the Oil Temp gauge rise !

old story / warning from my racecar days: (liquid cooled engines)

If your engine temp gauge suddenly goes _down_ while racing, that (usually) means you’ve lost your coolant because there’s no longer any hot coolant bringing heat from the engine to the sensor.
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Good point. In this case, though, the gage was inop and the engine was shut down on that basis apparently.
 
Take away that broken wiring harness. This flight was doomed for a big failure. That gear door was coming off on that flight and whacking the prop.
 
benyflyguy said:
Take away that broken wiring harness. This flight was doomed for a big failure. That gear door was coming off on that flight and whacking the prop.
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Possible, maybe even probable; but without the broken harness chances are the other engine would not have been shut down when it happened.

Nauga,
unhinged
 
nauga said:
Possible, maybe even probable; but without the broken harness chances are the other engine would not have been shut down when it happened.
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True. But after spending the entire previous flight well above vLE, they would have probably made the rest of the trip above vLE as well. So it's possible (almost probable) that at some point on that next flight one gear door was going to come off and once that happened, the other would have followed soon after.

Don,
departed
 
donjohnston said:
True. But after spending the entire previous flight well above vLE, they would have probably made the rest of the trip above vLE as well. So it's possible (almost probable) that at some point on that next flight one gear door was going to come off and once that happened, the other would have followed soon after.

Don,
departed
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We don't know how the second gear door would have reacted to the loss of the first one and that engine. Sideslip could have ripped it off immediately. Or it could have lasted forever. Indeed, the first gear door failure may have had help from the aerodynamics of the first engine being shut down. There are a few layers of Swiss cheese here, and from the cockpit it may have been quite difficult to recognize any of the pieces before the holes lined up.

Do you have any special considerations when you fly a retractable pusher, such as designing in a lower VLE, to account for the risk of airplane parts going through the propeller? Obviously we all respect VLE and friends, but if there is a buffer between the book VLE and VLGCFT (V-landing gear comes from together) I would want that buffer to be larger in a pusher.
 
iamtheari said:
We don't know how the second gear door would have reacted to the loss of the first one and that engine. Sideslip could have ripped it off immediately. Or it could have lasted forever. Indeed, the first gear door failure may have had help from the aerodynamics of the first engine being shut down. There are a few layers of Swiss cheese here, and from the cockpit it may have been quite difficult to recognize any of the pieces before the holes lined up.
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Had that oil pressure sending unit wire not broken, I see no reason that the pilot would have begun flying below vLE during the subsequent flights. After a few more hours of 30-50kts over vLE, I would not be surprised if one of the gear doors would have come off without any aerodynamic loads from a shutdown engine.

iamtheari said:
Do you have any special considerations when you fly a retractable pusher, such as designing in a lower VLE, to account for the risk of airplane parts going through the propeller? Obviously we all respect VLE and friends, but if there is a buffer between the book VLE and VLGCFT (V-landing gear comes from together) I would want that buffer to be larger in a pusher.
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Other than avoiding runways with loose gravel, no.

I will say that vLE on my XL-RG is 125kts. I thought it was the same on the twins.
 
The report states the left engine oil pressure sending unit harness had damage "not consistent with impact". Based on the photo, what do we suppose happened to it? Knicked accidentally during maintenance?
 

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Without knowing how the wires were routed and what was nearby, there's really no way to know for certain.

I would guess the wires were up against something that wore through the insulation.
 
The green wire looks like it has a worn in spot from chafing. The left end of the red wire looks pretty clean..
 
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