Multi-engine turboprop pop quiz

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PPC1052

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So, you're on take-off roll in your BE-200, and you have a sun gear failure. What do you do? Please explain your answer. (This is a like a law school exam, so I expect you folks to spot the issues.)
 
Im with Pilawt. Sunblock seems to be the only correct answer.
 
PPC1052 said:
So, you're on take-off roll in your BE-200, and you have a sun gear failure. What do you do? Please explain your answer. (This is a like a law school exam, so I expect you folks to spot the issues.)
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Nothing worse than a sun gear failure. ;)

:rofl::rofl::rofl:
 
Thats the one emergency scenario FlightSafety and Simcom won't pull on you in the sims. :hairraise:
 
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What speed are you at?

All else fails
9b6b7fa1e35cbab3ec4351d046e92fa4.jpg
 
Pull out the POH and flip to the section on how to fill out a warranty claim application?
 
PPC1052 said:
So, you're on take-off roll in your BE-200, and you have a sun gear failure. What do you do? Please explain your answer. (This is a like a law school exam, so I expect you folks to spot the issues.)
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Disclaimer: I know jack schitt[1] about turboprops, but

This is PoA, so what the hell: Sungear implies gearbox, and a sungear is in the middle (gussing) of a planetary gearset. So, if a sungear fails, the gearbox grenades, loud noises are made, and you lose power on that side. Depending on the damage, maybe you can't feather the prop? What do I win?

[1]
schitt-family-tree-blank-card-16.jpg
 
Oh, sun gear...like cheap sunglasses; mine fail all the time. What do I do? pull-out a new pair from the dozen in my flight bag. Why? Because they only cost about a dollar each - plus shipping and handling (magazine ad). Other important sun gear includes a broad-rimmed hat (I wear a sombrero with a hole on each side so the headset fits -- I used to roll-up the sides of the sombrero with headset on, but it looked really stupid -- lots of dirty looks).
 
King Air 200 is a Part 23 twin. If I'm on the takeoff roll, that means I haven't raised the gear handle yet. Barring extenuating circumstances (none were listed in the OP), if I haven't raised the gear handle, I'm aborting the takeoff.
 
You have lost an engine. If on the roll, wheels still on the ground, close throttles and use maximum braking. Regardless of gear position, if you are off the ground then this should have been considered before launching. Variables to consider: Take off weight, density altitude, obstacles, runway length. You should have a plan in place before take off for each phase of the flight through at least 1000 feet AGL. Know ahead of time what the plane is capable of for a given set of circumstances.
 
ronnieh said:
You have lost an engine. If on the roll, wheels still on the ground, close throttles and use maximum braking. Regardless of gear position, if you are off the ground then this should have been considered before launching. Variables to consider: Take off weight, density altitude, obstacles, runway length. You should have a plan in place before take off for each phase of the flight through at least 1000 feet AGL. Know ahead of time what the plane is capable of for a given set of circumstances.
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Gear position is a variable to consider...it's also a variable that you can control. If weight, altitude, & temperature don't give me the climb I need to clear obstacles single-engine, I'd rather land with the gear down than up. Many experienced pilots therefore, adjust the point of gear retraction to the point where the flight can be continued in the event of an engine failure.

"If you haven't raised the gear switch, abort...if you have, continue" then becomes a reasonable, and fairly important, statement.
 
Just hope it doesn't happen to a helicopter in flight. ;)
 
Why is this taking a serious tone with the past few posts? Let's get back on track! We're talking 'sun gear failure'!
 
You have a point but, we don't know which KA the OP is talking about. I assumed he meant a B200 (I don't think there is a Be 200) This is why I meant by that the plan needs to be made beforehand. A B200 lightly loaded, low density altitude is quite capable of climbing with gear down on one engine. Seems it would be hard to explain why you set it back down on a 3000 foot runway when you were 20 feet off the ground when you lost one. Thus I have to disagree with your comment. This is why IMO, when flying twin turbo props you must know the capabilities of your particular model (and pilot capability). Each TO is unique and needs to be planned out in advance as I mentioned. In a piston twin your comment has a lot more weight to it. Few piston twins with even a moderate load and moderate DA can even maintain altitude.
 
mscard88 said:
Why is this taking a serious tone with the past few posts? Let's get back on track! We're talking 'sun gear failure'!
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I assume this is a "tongue in cheek" comment. If you lose the sun gear in the gear box of a PT6 you have lost that engine. Just hope one of the governors prevent over speed and parts are not contained.
 
ronnieh said:
You have a point but, we don't know which KA the OP is talking about. I assumed he meant a B200 (I don't think there is a Be 200) This is why I meant by that the plan needs to be made beforehand. A B200 lightly loaded, low density altitude is quite capable of climbing with gear down on one engine. Seems it would be hard to explain why you set it back down on a 3000 foot runway when you were 20 feet off the ground when you lost one. Thus I have to disagree with your comment. This is why IMO, when flying twin turbo props you must know the capabilities of your particular model (and pilot capability). Each TO is unique and needs to be planned out in advance as I mentioned. In a piston twin your comment has a lot more weight to it. Few piston twins with even a moderate load and moderate DA can even maintain altitude.
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If I'm 20 feet off the ground in a lightly-loaded 200 (or B200, whichever you prefer...I don't think that's relevant to this discussion) with adequate performance to climb on one engine, the gear switch will be up...if I'm 20 feet off the ground in a moderately-loaded piston twin with a moderate DA such that it can't climb on one, the gear switch will still be down, and I'm reducing power to put it back down.

Just to avoid the whole comparison of apples and oranges that you made, if I'm taking off in a moderately-loaded 200 at moderate DA where I can't climb on one, the gear switch would still be down, and I would reduce power and land.

I DO know the performance and pilot capabilities in either case, which is WHY I adjust my go/no go point.
 
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Bill Jennings said:
Disclaimer: I know jack schitt[1] about turboprops, but

What do I win?
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Unfortunately, I can't give you any credit because you did not ask the question I asked. ("What do you do?") This is not to say that you didn't give a valiant effort, or that you embarrassed yourself.
 
ronnieh said:
You have lost an engine. If on the roll, wheels still on the ground, close throttles and use maximum braking. Regardless of gear position, if you are off the ground then this should have been considered before launching. Variables to consider: Take off weight, density altitude, obstacles, runway length. You should have a plan in place before take off for each phase of the flight through at least 1000 feet AGL. Know ahead of time what the plane is capable of for a given set of circumstances.
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I fear I may have misled. This is after rotation. No positive rate of climb. If it helps, V1=VR.
 
Bobanna said:
Sun gear failure seems irrelevant: All I could know as pilot is that I've hatched an engine and lost power.

All of the "issues" pertain to multi-engine operations on any takeoff (hence a detailed takeoff briefing every time), and the esoteric notion of a sun gear failure is a distraction of sorts (no annunciator specifically for sun gear failure). How would the pilot know, and why would he/she care? Hopefully, close the throttles, stop, and sort it out with maintenance.
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Now we're getting to something interesting (to me, at least).

Can you elaborate on this issue--no annunciator, in particular. What should the confused pilot think?
 
The OP did ask what would "you" do. So perhaps that is the correct answer for you. Most turboprops require recurrent training in a sim and the point is that in turbo props the answer is it depends. If you are using the gear position as a go/no go then fine. It is not the way it will be taught in sim training. The B200 has better performance than a straight 200 so I assumed the B model. I will concede that if the gear is down and you don't know the performance of the aircraft then it may be safer for you to simply set it back down. In fact even if you do know the performance and you do know it will continue to climb with gear down it still might be safer for you to set it back down. Running off the end of the runway is safer than nosing in from 50 feet. However if I know the plane will climb and the gear is still down and I am on a typical GA runway I am going to continue and get things cleaned up and engine secured as soon as practical.
 
ronnieh said:
The OP did ask what would "you" do. So perhaps that is the correct answer for you. Most turboprops require recurrent training in a sim and the point is that in turbo props the answer is it depends. If you are using the gear position as a go/no go then fine. It is not the way it will be taught in sim training. The B200 has better performance than a straight 200 so I assumed the B model. I will concede that if the gear is down and you don't know the performance of the aircraft then it may be safer for you to simply set it back down. In fact even if you do know the performance and you do know it will continue to climb with gear down it still might be safer for you to set it back down. Running off the end of the runway is safer than nosing in from 50 feet. However if I know the plane will climb and the gear is still down and I am on a typical GA runway I am going to continue and get things cleaned up and engine secured as soon as practical.
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depends on the sim instructor.

And as I said in my first post, extenuating circumstances may change things, but the OP didn't present any that would.
 
PPC1052 said:
I fear I may have misled. This is after rotation. No positive rate of climb. If it helps, V1=VR.
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Is VR>VMC ? I know in the P180 that it was usually not greater than VMC. In this case you hope auto-feather works as tested. Still probably try to stuff it back on the runway if there's reasonable reason to believe enough exists and that was in the briefing.
 
ronnieh said:
The OP did ask what would "you" do.
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Yes, I did. I am looking for perspective, not necessarily the book answer. That is, unless the book answer is your perspective.
 
PPC1052 said:
Now we're getting to something interesting (to me, at least).

Can you elaborate on this issue--no annunciator, in particular. What should the confused pilot think?
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You will not have any indication in the cockpit that you had a sun gear failure. For example if you lost oil pressure you will have a specific warning on the annunciator panel as well as an oil pressure indicator. A gear box failure will of course cause loss of torque on that engine, you may get some turbine overspeed indications. I am not familiar at all with the B200 so I don't know all of the annunciators. Suffice to say if you lose a gearbox you are flying on one engine at best. Appropriate engine out procedures are called for.
 
Without a doubt. A dead give away is the plane trying to swap ends.
 
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