Twin Engine Failure With A/P Engaged

Fearless Tower

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Saw this posted on Beech Talk and thought it was worth sharing.

http://youtu.be/dW2bINfbGsY

BE58 in cruise with A/P on. No pilot input. Mixture pulled to cutoff on the critical engine.

Many ME instructors and seasoned pilots will often insist on kicking off the A/P as soon as something goes wrong.....but is that really the best advice?

Take your time. You have it. There is no rush.
 
In my Travelair you could hardly tell a motor was out,if the auto pilot was engaged. With the auto pilot engaged you have time to run the checklist and trouble shoot,the problem.
 
That was the crappiest engine failure demo I have ever seen. Not that I disagree that you have plenty of time to calmy go about dealing with things and running through procedures, but that demonstration and presentation was such crap it showed nothing. Just cut the mixture, and leave it alone and see what happens, quit messing with crap, and give a broader view of what is going on, maybe even a PIP of the ASI in the corner of a full panel shot.
 
Saw this posted on Beech Talk and thought it was worth sharing.

http://youtu.be/dW2bINfbGsY

BE58 in cruise with A/P on. No pilot input. Mixture pulled to cutoff on the critical engine.

Many ME instructors and seasoned pilots will often insist on kicking off the A/P as soon as something goes wrong.....but is that really the best advice?

Take your time. You have it. There is no rush.

In THE COMPLETE MULTIENGINE PILOT I counsel my readers to "Don't just do something, sit there!!" Unless an engine fails immediately after liftoff during initial climb there should be no rush to do anything, autopilot or no autopilot.

Bob Gardner
 
In THE COMPLETE MULTIENGINE PILOT I counsel my readers to "Don't just do something, sit there!!" Unless an engine fails immediately after liftoff during initial climb there should be no rush to do anything, autopilot or no autopilot.

Bob Gardner

Well, except when you know it's coming and you reach down real quick to switch the fuel tank before the engine fully cuts out as the aux tank runs dry.;)

Yeah, engine failures in cruise are pretty much a non event. Once I have 200'/clear and Blue+5 I start to relax. I do however buy myself that relaxation with weight discipline and horsepower, I am always well below gross, with the 310 I always operated at weights that would give me a solid rate of climb on a single below 4000' and a positive to 7500', and that was in hot, humid, south Florida summer. Baron gives the same performance, heck, even my Travelair I could get 500fpm in SoCal.

The habit you have to give up when you start flying twins is to always top off the tanks. You need greater preflight fuel management discipline (and a totalizer really really helps here) to just take the fuel you need on any flight. When you stop, you figure out how much you need to the next stop plus whatever you need to make a happy margin, and just add the fuel you need to make that number.
The saw of "3 useless things in aviation, altitude above you, runway behind you, and fuel on the ground" has to get modified when you get in twins.
 
Our King Air will hold the plane just fine in cruise if an engine fails. In the Citation, the checklist requires AP off, retrim and back on as auto trim won't keep up.

Best,

Dave
 
Our King Air will hold the plane just fine in cruise if an engine fails. In the Citation, the checklist requires AP off, retrim and back on as auto trim won't keep up.

Best,

Dave

Huh, I'm surprised it makes that big of a difference on a Citation.
 
One time I was flying right seat in a T310R on a long cross country from Long Beach to Atlanta, and we went way up high to catch a good tail wind. We made some O2 calculations and decided we should limit flow during the daylight hours so we were sure to have plenty after dark. We had just done a bunch of turbo work, and when the right engine died, it was assumed we still had a mechanical issue and started dealing with it, got a diversion to another airport, started going through things when finally it hits him, he switches fuel tanks, and BRRRRRR....:lol: As hypoxic as we were, control of the aircraft was never really an issue.
 
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In THE COMPLETE MULTIENGINE PILOT I counsel my readers to "Don't just do something, sit there!!" Unless an engine fails immediately after liftoff during initial climb there should be no rush to do anything...
...other than to control the airplane with your hands and feet on stick/yoke and rudder -- that you gotta do before things do get out of hand. Just don't get crazy about grabbing for other things like engine levers, mag switches, fuel valves, and the like in any kind of big flaming hurry. Case in point was the Piper twin pilot flying at night who reached over to the bank of switches on the left wall to turn off the fuel pumps, and had an engine failure as he did it. Long story short is how after feathering the engine he went to turn off the mag switches and discovered they were already off but the fuel pumps were still running. oops. :redface:

FOr those unfamiliar with that design...

Picture6.jpg
 
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...other than to control the airplane with your hands and feet on stick/yoke and rudder -- that you gotta do before things do get out of hand. Just don't get crazy about grabbing for other things like engine levers, mag switches, fuel valves, and the like in any kind of big flaming hurry. Case in point was the Piper twin pilot flying at night who reached over to the bank of switches on the left wall to turn off the fuel pumps, and had an engine failure as he did it. Long story short is how after feathering the engine he went to turn off the mag switches and discovered they were already off but the fuel pumps were still running. oops. :redface:

FOr those unfamiliar with that design...

Picture6.jpg

I think that we kind of agree: Doing something wrong really fast will ruin your whole day. I have had only one shut-down-and-feather and it happened in cruise at 14,000 feet. My takeaway is that you have time to think before doing except in the circumstance I described.

Bob
 
Our King Air will hold the plane just fine in cruise if an engine fails. In the Citation, the checklist requires AP off, retrim and back on as auto trim won't keep up.
In our Citation we can leave it on. :)
 
I think that we kind of agree: Doing something wrong really fast will ruin your whole day. I have had only one shut-down-and-feather and it happened in cruise at 14,000 feet. My takeaway is that you have time to think before doing except in the circumstance I described.
Right with you there, Bob. Like Captain "Tooter" Teague told me back in 1974 the first time I (then a very young ensign) I flew with him -- "If an emergency starts, wind the clock. Once you've done that, take a deep breath, then get out the checklist and deal with it." Too bad all the clocks are electric now.
 
In our Citation we can leave it on. :)

Well depending on which citation you are flying you are either in one of the fastest certified business jets in production of one of the slowest. I'm sure the auto flight capability across the various versions of aircraft called citation is very diverse. :wink2:
 
Well depending on which citation you are flying you are either in one of the fastest certified business jets in production of one of the slowest. I'm sure the auto flight capability across the various versions of aircraft called citation is very diverse. :wink2:
I am in the 680, which is not the fastest but on the larger side, for Citations that is.
 
I am in the 680, which is not the fastest but on the larger side, for Citations that is.

Never flown one but have had the dime tour. Its a nice airplane. I am typed in the the 500 series and flew a II for a few years. Definitely the slowest jet I have ever flown. It was however a super easy aircraft to operate. Have a few hours of pulling gear in a 7 for a friend when his normal gear monkey was unavailable. That was a really nice aircraft.
 
I always thought our 680's were a easier/simpler
Airplane than any of the 500 series.
I just wish I would have gotten a chance to fly the +.
Dave
 
To to OP. It depends on the aircraft. Look in the limitations section for ap limitations and review the checklist for engine out procedures. Some aircraft/ap systems are designed to handle an engine failure some are not. Even with the ones that are not, I have not found one yet that couldn't quickly be turned back on after the engine was secured and aircraft trimmed.

Bottom line is I use the AP as much as safely possible during emergencies. Frees me up to deal with the problem.
 
I always thought our 680's were a easier/simpler
Airplane than any of the 500 series.
I just wish I would have gotten a chance to fly the +.
Dave

I've never flown any other Citation besides the 680. My background was in older Lears (35 and 55) and the Hawker 800. The 680 is definitely simpler (and much more modern) than any of those. Design has come a long way since the 1970s and 80s.
 
Citation II (550) Engine Failure During Coupled Approach:
1. Power (operating engine) INCREASE as required.
2. AP and yaw dampener OFF.
3. Airspeed - VREF plus 10
4. Rudder trim - TRIM toward operating engine.
5. Flaps T.O. & Approach

For a precautionary shut down, AP isn't mentioned.

Citation V seems to be the same.

Dave
 
In THE COMPLETE MULTIENGINE PILOT I counsel my readers to "Don't just do something, sit there!!" Unless an engine fails immediately after liftoff during initial climb there should be no rush to do anything, autopilot or no autopilot.

Bob Gardner

Bob, I have recommended your CMEP book to folks for 15 years. It's the best book on multi-engine flying there is. Simple, precise, and effective.
 
In THE COMPLETE MULTIENGINE PILOT I counsel my readers to "Don't just do something, sit there!!" Unless an engine fails immediately after liftoff during initial climb there should be no rush to do anything, autopilot or no autopilot.

Bob Gardner

Bob, I have recommended your CMEP book to folks for 15 years. It's the best book on multi-engine flying there is. Simple, precise, and effective.

I own a copy as well, great book.
And I have occasionally quoted your "sit there" phrase as well, it is a good one. I've heard of some MEIs requiring that a student identify, verify and secure a failed engine in under 2 seconds. Let me just say that I choose not to fly with those MEIs.
Thank you, Bob.
 
I've never flown any other Citation besides the 680. My background was in older Lears (35 and 55) and the Hawker 800. The 680 is definitely simpler (and much more modern) than any of those. Design has come a long way since the 1970s and 80s.

Interesting. I thought APs controlled roll with ailerons alone and didn't put in rudder trim; that's what lead some planes to stall when left in AP after an engine failure. Does your AP also adjust rudder trim? My KA doesn't. The AP will hold it in cruise, but a good idea to trim the rudder manually.

I think a Korean Airlines plane got in deep dodo when the AP was left on and the plane rolled right (when aileron trim ran out) while the captain had his head down trying to fix the engine problem.
 
Interesting. I thought APs controlled roll with ailerons alone and didn't put in rudder trim; that's what lead some planes to stall when left in AP after an engine failure. Does your AP also adjust rudder trim? My KA doesn't. The AP will hold it in cruise, but a good idea to trim the rudder manually.

I think a Korean Airlines plane got in deep dodo when the AP was left on and the plane rolled right (when aileron trim ran out) while the captain had his head down trying to fix the engine problem.

Depending on the plane, the autopilot will trim the rudder. The AP on the Airbus does. During a V1 cut after airborne you can engage the AP and let it trim out the rudder for you.

You are refering to an China Airlines Flight 006 on a B747SP.
 
Interesting. I thought APs controlled roll with ailerons alone and didn't put in rudder trim; that's what lead some planes to stall when left in AP after an engine failure. Does your AP also adjust rudder trim? My KA doesn't. The AP will hold it in cruise, but a good idea to trim the rudder manually.

I think a Korean Airlines plane got in deep dodo when the AP was left on and the plane rolled right (when aileron trim ran out) while the captain had his head down trying to fix the engine problem.
There is such a thing as a 3axis autopilot which I would assume means integrated control of rudder as well as pitch and roll. OTOH, a simple yaw damper would probably keep the ball centered and leave the plane in a sideslip unless you dialed in some yaw damper trim.

And chances are the sideslip would be much worse at approach speed vs cruise so it makes sense that more pilot input would be required then.
 
...other than to control the airplane with your hands and feet on stick/yoke and rudder -- that you gotta do before things do get out of hand. Just don't get crazy about grabbing for other things like engine levers, mag switches, fuel valves, and the like in any kind of big flaming hurry. Case in point was the Piper twin pilot flying at night who reached over to the bank of switches on the left wall to turn off the fuel pumps, and had an engine failure as he did it. Long story short is how after feathering the engine he went to turn off the mag switches and discovered they were already off but the fuel pumps were still running. oops. :redface:

FOr those unfamiliar with that design...

Picture6.jpg

Looks like a nice Seneca.
 
Interesting. I thought APs controlled roll with ailerons alone and didn't put in rudder trim; that's what lead some planes to stall when left in AP after an engine failure. Does your AP also adjust rudder trim? My KA doesn't. The AP will hold it in cruise, but a good idea to trim the rudder manually.
With the exception of yaw damp, the 680 AP doesn't put in rudder trim but you can do it yourself even with the AP engaged.
 
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