SE ops in a AMEL?

Pi1otguy

Pi1otguy

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Wondering about the KVGT crash today. Are most light twins able to maintain level flight on one engine? If not, is there a specific reason why it design consideration why?
 
if the plane weighs under 6000lbs it is not required to be able to maintain altitude on 1 engine.

in my experience, it can really depend on the conditions of the day (weight of plane/ payload/ fuel / density altitude/ temp)
 
They can, however the single engine ceiling is a lot lower than the normal ceiling. In the ones I've flown it's been around 4000 ft in standard conditions at max weight. If the terrain is higher you'll eventually meet the ground. Hope that helps.
 
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Pi1otguy said:
Wondering about the KVGT crash today. Are most light twins able to maintain level flight on one engine? If not, is there a specific reason why it design consideration why?
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Manufacturers of light twins with gross weights <6000 pounds with stall speeds less than 61 knots m
need only determine the engine-out climb or descent rate, they don't have to prove that it can maintain level flight; airplanes weighing > 6000 pounds must demonstrate a positive climb rate with one prop feathered.

Proficiency is the great leveler among twin pilots faced with an engine out.

Edit: Now I see that the poor devil had an engine fire. Absent a nacelle extinguishing system, normal procedures and regulatory niceties go out the window. He did what he could with what little he had available. Do not read normal engine-out procedures into this accident.


Bob Gardner
THE COMPLETE MULTIENGINE PILOT
 
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ntbjounin said:
if the plane weighs under 6000lbs it is not required to be able to maintain altitude on 1 engine.

in my experience, it can really depend on the conditions of the day (weight of plane/ payload/ fuel / density altitude/ temp)
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And pilot. From my limited experience, single engine ops on a light non-turbo twin (Seminole) are dicey. They climb like a quadrapeligic grandmother on quaaludes.
 
flyersfan31 said:
And pilot. From my limited experience, single engine ops on a light non-turbo twin (Seminole) are dicey. They climb like a quadrapeligic grandmother on quaaludes.
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But this was a Navajo. There are non-turbo PA-31s but I have never flown one. Richard L. Taylor once told me that he would not go around on one engine in anything smaller than a King Air.

Bob Gardner
 
All twins have a single engine service ceiling. This is the altitude where the airplane can maintain a 50 FPM rate of climb on a single engine in the most favorable configuration (other prop feathered, flown properly, clean, etc).

This ceiling is a density altitude (or, put another way, is dependent on atmospheric conditions like temperature and pressure).

The single engine service ceiling published for the Seminole I've got a POH handy here is about 5000 feet at max gross. That means that if I'm at 8000 and I lose an engine - I'm going to have to descend (drift down), and somewhere around 5000 I'll be able to maintain altitude.

This can be BAD if I'm in a spot where the minimum enroute altitude or safe altitude is say.... 6000. Even Boeings will drift down - of course it will be from 35000 to 22000 or so, depending on the model and weight/weather.

Back to the Seminole or other light twins - losing one engine can mean losing 80% of excess thrust (which is what makes the airplane climb). That means that in some conditions a failure after takeoff means you come back to earth more slowly than in a single, but you're coming back.

Where most people kill themselves in light twins is by doing the same thing they do in a single with an engine failure - they ignore airspeed and pull back and increase pitch. In a single, you get a stall and possibly a spin. In a twin with one out, you get an uncontrollable yaw followed by a roll and end up UWOF (Upside-down in the Weeds, On Fire) and very very dead.

My drill in a light twin is that if I lose one after rotation, unless I'm already clean, and I KNOW (by having done it at altitude) that I can climb in this configuration in this airplane, I'm gonna pull back BOTH engines, and crash straight ahead under control.

As noted above, in this incident with a fire on board - the drill is to secure fuel to that engine, and get down and out of the airplane as fast as possible. Maybe pulling both back and gliding would be a good choice, but I don't know enough about this situation.
 
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Actually, there is a requirement for light twins to be able to climb on one engine at a 3% (or is it 3 degree?) gradient -- at sea level, standard day, cleaned up. However, like all other performance specs, it need only be met with a brand new airplane with a brand new engine and a brand new prop and a test pilot flying it. In most cases, the non-turbocharged light twins run out of climb by book specs around 4000-6000 feet.

That said, if you're a couple-three hundred pounds below max gross, most all light twins will fly and even climb pretty well on one engine at 5000 or below as long as they're clean.

But beyond that, when you throw fire into the equation, it's a whole 'nother story. It can be pretty hard to focus on flying a perfect single-engine procedure when there's a fire blazing four feet from you with nowhere to get away from it. Further, if you can't extinguish the fire pretty quick, that aluminum structure burns through in short order, and then you're out of options.
 
Tim, you mention driftdown. Your numbers are pretty close. The E-3(707) can climb to approx. 31000ft at 320,000 lbs. on a standard day, but if we lose an engine we are drifting down to about 23,000ft. One thing that plays into the solution for us at least is the airspeed in which we drfitdown. At that weight it will be about .66M to 250kias. Any faster/slower and we fall to the driftdown altitude and maybe not clear the high terrain.

Ron, I think It's 3 degrees. For USAF Heavies, we are required at least 250' per nm. That translates in our book to about 3.3 degrees I think.
 
AWACSEng said:
Ron, I think It's 3 degrees. For USAF Heavies, we are required at least 250' per nm. That translates in our book to about 3.3 degrees I think.
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After further review, it's 1.5% at 5000 feet for light twins. Ref: 14 CFR 23.67(a).
 
OK, sounds good. Another differnce between civil and mil flying.
 
bobmrg said:
Manufacturers of light twins with gross weights <6000 pounds with stall speeds less than 61 knots m
need only determine the engine-out climb or descent rate, they don't have to prove that it can maintain level flight;

Bob Gardner
THE COMPLETE MULTIENGINE PILOT
Click to expand...

Ron Levy said:
Actually, there is a requirement for light twins to be able to climb on one engine at ....
Click to expand...

Ron Levy said:
After further review, it's 1.5% at 5000 feet for light twins. Ref: 14 CFR 23.67(a).
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But if you continue to 23.67(b), it appears that Bob is right...
(2) For each airplane that meets the requirements prescribed in §23.562(d), or that has a VSOof 61 knots or less, the steady gradient of climb or descent at a pressure altitude of 5,000 feet must be determined with the—
(i) Critical engine inoperative and its propeller in the minimum drag position;
(ii) Remaining engine(s) at not more than maximum continuous power;
(iii) Landing gear retracted;
(iv) Wing flaps retracted; and
(v) Climb speed not less than 1.2VS1.
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Fly safe!

David
 
Greetings all, new to PoA, and picked up on this thread. The Navajo at VGT should have been able to maintain altitude back to the airport. One report was that the SE service ceiling is about 13000MSL. He was solo with about 200gal of fuel on board.
He had a reported fire on one engine and was making his way back. There was one unconfirmed report that the second engine also failed so he did not make it back.

BTIZ, VGT Pilot
 
BillTIZ said:
Greetings all, new to PoA, and picked up on this thread. The Navajo at VGT should have been able to maintain altitude back to the airport. One report was that the SE service ceiling is about 13000MSL. He was solo with about 200gal of fuel on board.
He had a reported fire on one engine and was making his way back. There was one unconfirmed report that the second engine also failed so he did not make it back.

BTIZ, VGT Pilot
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Thanks for the info... I think fire is a "get it down NOW wherever" rather than a "get back to the airport" scenario. (Right, Chip? :eek:) Yikes. :hairraise:
 
Short of airplanes with remote extinguishers in the engines, I've never seen a fire checklist that didn't end with LAND IMMEDIATELY. To me that does not mean waiting for an airport.
 
About the only place worse than an airplane to have a fire is a submarine -- no way out at all, and it's a lot easier to get a plane down than a submarine up. I have personally watched a light twin go down in flames because the pilot tried to get to an airport rather than shut down the affected engine and land on the first available piece of dirt. It's just another example of folks making bad decisions in light twins that they'd never make in a single.
 
Ron Levy said:
I have personally watched a light twin go down in flames because the pilot tried to get to an airport rather than shut down the affected engine and land on the first available piece of dirt. It's just another example of folks making bad decisions in light twins that they'd never make in a single.
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Seems to me a contributor to this board put his Baron 55 into the woods when it had a heater fire once upon a time.
 
Ken Ibold said:
Seems to me a contributor to this board put his Baron 55 into the woods when it had a heater fire once upon a time.
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I think it was a 58P and from what I remember the 'only tree in kansas' can't be considered a wooded area :) but im sure he can straighten us out.
 
tonycondon said:
I think it was a 58P and from what I remember the 'only tree in kansas' can't be considered a wooded area :) but im sure he can straighten us out.
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Obviously he was trying to fly between two trees to shear the wings off, and lessen the impact of the crash...
 
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SAS ran the checklist. The box-haulers said screw it and landed. One group watched the airplane burn from the ramp, the other from inside as they plunged into the ocean. Which sounds better?

TMetzinger said:
Short of airplanes with remote extinguishers in the engines, I've never seen a fire checklist that didn't end with LAND IMMEDIATELY. To me that does not mean waiting for an airport.
Click to expand...
 
flyingcheesehead said:
Thanks for the info... I think fire is a "get it down NOW wherever" rather than a "get back to the airport" scenario. (Right, Chip? :eek:) Yikes. :hairraise:
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From where he was in the valley.. it was just as far to a suitable landing in the desert or any open area.. as it was to get back to the airport.
BT
 
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