Cat Driver: I am tired of your instructor bashing

[Hedley]

It is ok to fly below blue line

Yes, briefly However, if only one prop is
turning, and you are at low altitude and low airspeed
you will have a great deal of difficulty trying to achieve
any positive rate of climb, in a piston prop twin.

What pilots do in this situation is instinctively raise
the nose to a normal climb angle, which almost
always results in a Vmc demo and the death of
everyone on board.

Piston prop twins must be treated with great respect
at slow airspeeds and low altitudes. Often the
best choice for an EFATO is to pull both throttles
and LAND under control, instead of inverted after
a Vmc demo.

[Cat Driver]

Airspeed indicators are great, but they are not always accurate nor can any pilot read one or two knots as the needle is that wide.

There will be instances where you can live to fly another day by maintaining control by preventing yaw with rudder and to a lesser extent ailerons just above VMC and if it won't climb or maintain altitude you can at least have a chance of crashing in the softest place ahead of you still under control and right side up..

Remember should an engine fail at low altitude it is better have airspeed you don't need than need airspeed you don't have.

[jetflightinstructor]

Quote:
It is ok to fly below blue line


Yes, briefly However, if only one prop is
turning, and you are at low altitude and low airspeed
you will have a great deal of difficulty trying to achieve
any positive rate of climb, in a piston prop twin.

Yes briefly, agreed. One definition of briefly could be:
If the engine fails during the climb out in a clean configuration, establish VYXE and once you have cleared any obstacles, accelerate to VYSE (blue line).

*note: most of the time VYSE is below blue line. Blue line is calculated at see level, max weight, critical engine failed.
You can have a VYSE 10 knots below blue line, be aware. Better to check in your AFM before the take off, and at the same time better to check if you are going to climb that day with the temperature, alt. pressure....

What pilots do in this situation is instinctively raise
the nose to a normal climb angle, which almost
always results in a Vmc demo and the death of
everyone on board.

VMC demo is an exercice practiced with your instructor, no real engine failure. (VMC demonstration).
In this case you want to say: loss of directional control.

Piston prop twins must be treated with great respect
at slow airspeeds and low altitudes. Often the
best choice for an EFATO is to pull both throttles
and LAND under control, instead of inverted after
a Vmc demo.

Yes that is an option. if the gear is up though, that is not foolish to continue to fly, the AFM has to be checked before the flight though.
Especially: short runway, low temperature, low altitude pressure, obstacle at the end of the runway: in this case sure, it would be foolish to stop the flight.

Airspeed indicators are great, but they are not always accurate nor can any pilot read one or two knots as the needle is that wide.

Sure. However there is usually 25-30 knots between red line and blue line...

Remember should an engine fail at low altitude it is better have airspeed you don't need than need airspeed you don't have.

Sure, here is all our problem
But we cannot chose at what speed the engine will fail...

* note: if you have an engine failure with the gear still down, land in front of you, you won' t be able to climb. (we are still speaking about small twin here).

[Cat Driver]

* note: if you have an engine failure with the gear still down, land in front of you, you won' t be able to climb. (we are still speaking about small twin here).

Yes, most who read this training forum will be learning on low performance light piston engine twins.....these suckers can be flown looking out the windshield during the initial part of the take off / climb....

......a big jet on the other hand does not generally give you much to look at with the deck angle they climb at....and you don't learn on the airplane anyhow.

Lets put it this way..I'd far rather lose an engine on a Boeing during the initial climb than on a 150 HP Apache.

[Big Pistons Forever]

I really liked flying the VG equiped Cessna 340. It had a blue line of 100 kts. If the oleo's are properly inflated it also sat dead level so you could comfortably use zero flap 100 kts as V1 and Vr. The bottom line was rotate, positive rate and gear up and if the engine failed you were either still on the ground or in a good position to fly away. If the the runway was 5000 ft or longer and at or near ISO conditions you also had balanced field.

[jetflightinstructor]

Twins with One Engine Out, rate of climb.


Beech Baron 58
382


Beech Duke
307


Beech Queen Air
210


Cessna 310
327


Cessna 340
250


Cessna 402B
225


Cessna 421B
305


Piper Aztec
240


Piper Navajo Chieftain
230


Piper Pressurized Navajo
240


Piper Seneca
190


I won' t fly the same a piper seneca or a beech baron 58 if I have an engine failure after rotate.
The temperature, weight, alt. pressure have to be taken into account.
Sometimes you won' t be able to climb on one engine. Some times you will climb at 500 feet per minute.
It has to be calculated before each flight, it would change completely the procedure.

Example: piper seneca, you have no experience, the runway is at 4000 feet altitude. Better to land in front of you if you have an engine failure before blue line at very low altitude.

You are experienced, you are light, and you fly a Beech baron 58: better to continue to fly.

[Hedley]

Better to land in front of you if you have an engine failure before blue line at very low altitude.

Excellent advice. And rarely heeded.

[iflyforpie]

Could somebody explain to me why retracting the gear after blue line is safest than below blue line?

Below blue line, you are on the back side of the single engine power curve. This means most of your now reduced power is going into overcoming induced drag and trying to climb. Retracting the gear is only going to have a minimal effect on overall drag before blue line.

Better IMHO to rotate, unstick the aircraft, fly in ground effect to accelerate to blue line (doesn't have to be totally level, but also not a positive rate), establish positive rate and THEN retract the gear. You will get to blue line just as fast or faster, and you will be in a position to plunk the plane back down if you are below blue line with an engine failure (we are talking underpowered twin here).

Considerations for pulling the gear up right away before blue line are:
Increased drag during cycling on some aircraft. No hydraulics if single pump is on the failed engine.

[Cat Driver]

Better IMHO to rotate, unstick the aircraft, fly in ground effect to accelerate to blue line (doesn't have to be totally level, but also not a positive rate), establish positive rate and THEN retract the gear.

Terrific idea especially on short strips and at night off runways in the boondocks where the black hole effect is so common.

[iflyforpie]

Sometimes you just have to decide when to crash and do risk management for the fields you use and the situations you operate in. In an underpowered twin (read Apache 150, Travelair, Seneca, Seminole, Dutchess, Cougar, etc) if you are below blue line it is going to be hairy accelerating and eeking a climb out of them-especially at high DA.

The worst thing that is going to happen if you decide that below blue line you are going to abort the takeoff is pretty much the same as what would happen in a high performance single with EFATO. Overrun the runway, take out some approach lights, run into the fence. Some cuts and bruises and an aircraft written off.

If I try to keep the thing airborne (in a case where it doesn't want to climb, I'm not going to crash a plane that is showing adequate performance) I run the risk of the whole stall, spin, die scenario.


If the position of the landing gear is the difference between life and death below blue line, you are cutting your margins too thin.

Terrific idea especially on short strips and at night off runways in the boondocks where the black hole effect is so common.

I'm not sure if this is sarcasm but I'd rather be cutting grass at the end of the runway than trying to maintain attitude and clear of terrain single-engine, underpowered twin, below blue line in a black hole situation.

[jetflightinstructor]

Below blue line, you are on the back side of the single engine power curve. This means most of your now reduced power is going into overcoming induced drag and trying to climb. Retracting the gear is only going to have a minimal effect on overall drag before blue line.

That' s forgeting that most of the time VYSE is below blue line. That' s forgeting that below VYSE you have VXSE.

If I calculate that I would climb at 500 feet per minute, and my gear is already up, I won' t stop the flight crash in the trees. I will continue.

And what about water at the end of the runway?

There is no only one answer. Performance of the airplane, abilities of the pilot, runway, environment.

If I try to keep the thing airborne (in a case where it doesn't want to climb, I'm not going to crash a plane that is showing adequate performance) I run the risk of the whole stall, spin, die scenario.

So here takes place the training. With 2 engines (small twin), blue line will be reached with an average of 8 degrees pitch up. With one engine out, an average of 1.5-2 degrees pitch up. If you monitor the speed, the pitch, and you are paid to be a pilot, a pilot properly trained (not only the TC minimums), you are able to avoid VMCA (red line) then avoid to spin. And if you have done your calculations on the ground, you know that you are able to climb.

Better IMHO to rotate, unstick the aircraft, fly in ground effect to accelerate to blue line (doesn't have to be totally level, but also not a positive rate), establish positive rate and THEN retract the gear.

Sorry but this is a weird procedure that you describe to us. If it had saved life in the past, we would know by now.
Fly in ground effect with the gear down until blue line... well well well...

Remember: one rule that really works because it has been used: positive climb, gear up.
Remember: easiest to gain altitude between VX and VY with 2 engines. If you have an engine failure near the ground with gear down, and propeller windmiling, and loose 3 or 4 meters (9 or 12 feet): you crash into the trees. Why? when you have an engine failure, it takes few seconds to feather, and set a proper angle of bank. By this time YOU DON' T CLIMB (blue line or 5 knots below the same). You level off without loosing speed. at 100 or 200 feet no problem. On 2 engines you climb at 1000-2000 feet per minutes, an average of 100 feet each 4.5 seconds. 20 feet each seconds.
with engine out, before you feather the prop, you don' t climb. Too bad you didn' t use the climb capabilities earlier on two engine because now instead of being at 200 feet in clean configuration (gear up), you are (yes maybe 10 knots faster) just above the ground gear down and propeller windmiling. You will be at blue line, select the gear up, but it takes an average of 5-10 seconds to raise.
You will pitch up (probabely more than 2 degrees-not recomended) because you are too low but have some speed, but because this landing gear is in transition now, (creating more drag than in down and lock position) you won' t climb but just decrease speed.Good luck to avoid the trees mountains power line building obstacles.

Retracting the gear is only going to have a minimal effect on overall drag before blue line.

You have a special idea about the amount of drag the landing gear creates on a small twin. Minimal effect?

[Cat Driver]

Sorry but this is a weird procedure that you describe to us. If it had saved life in the past, we would know by now.

That is a new one to me to jetflightinstructor.....that is why I questioned his method.

Fly in ground effect with the gear down until blue line... well well well...

Yeh, I'm also amazed by that one, unorthodox is the only description I can think of.

[jetflightinstructor]

Yes sure Cat. We seem to have the same understanding about an engine failure after T/O.

On a jet we just have to folow the SOPs (that are from the AFM, concerning the engine out procedures). And there is no place for creativity: after V1: FLY!!!

On a small twin though I understand that the procedure may vary with:

-pilot experience
-aircraft
-weather
-runway
-environment

After the engine out calculation BEFORE the flight, the procedure has to be established.
Decision point at altitude or not?
Obstacle or not? initial climb at VX or VY?
Able to climb or not (is 50 feet per minute a climb? the answer is no).

A safety T/O briefing has to be done accordingly.

So I really can understand that some can be creative. But this creativity has some limit, the AFM one.

The huge problem behind that is the training. An engine failure in a small twin will end up in a fatal crash 4 times more than in a single engine....
A sim training has to be done (FTD), VMC demo has to be demonstrated, and the exercice (engine failure after T/O) in addition has to be done (simulated) at altitude in the aiplane. But who does that??? I always hear around me "get the cheapest multi training you can find". So when you go to the super market you buy the cheapest food you can find, whatever the result on your health?

Here it is the same. What ever the result on the safety?
With a proper training nobody would rise the nose 10 degrees up if an engine failure occures after T/O. (the max is 1.5 - 2 degrees). But if you never practice it, how would you know?

So because of the lack of training and knowledge, we tend to touch nothing before blue line.
I guess tis is maybe the safest way with the actual level of training.
The safest would be: apply the proper procedures by well trained pilot. And know before each flight your aircraft performance. A dream?

[Big Pistons Forever]

Yes sure Cat. We seem to have the same understanding about an engine failure after T/O.

On a jet we just have to folow the SOPs (that are from the AFM, concerning the engine out procedures). And there is no place for creativity: after V1: FLY!!!

On a small twin though I understand that the procedure may vary with:

-pilot experience
-aircraft
-weather
-runway
-environment

After the engine out calculation BEFORE the flight, the procedure has to be established.
Decision point at altitude or not?
Obstacle or not? initial climb at VX or VY?
Able to climb or not (is 50 feet per minute a climb? the answer is no).

A safety T/O briefing has to be done accordingly.

So I really can understand that some can be creative. But this creativity has some limit, the AFM one.

The huge problem behind that is the training. An engine failure in a small twin will end up in a fatal crash 4 times more than in a single engine....
A sim training has to be done (FTD), VMC demo has to be demonstrated, and the exercice (engine failure after T/O) in addition has to be done (simulated) at altitude in the aiplane. But who does that??? I always hear around me "get the cheapest multi training you can find". So when you go to the super market you buy the cheapest food you can find, whatever the result on your health?

Here it is the same. What ever the result on the safety?
With a proper training nobody would rise the nose 10 degrees up if an engine failure occures after T/O. (the max is 1.5 - 2 degrees). But if you never practice it, how would you know?

So because of the lack of training and knowledge, we tend to touch nothing before blue line.
I guess tis is maybe the safest way with the actual level of training.
The safest would be: apply the proper procedures by well trained pilot. And know before each flight your aircraft performance. A dream?

50 yrs ago accidents following an EFATO in large aircraft were not that unsual. Now they are virtually unheard of. More reliable engines and systems certainly help but IMO the main reason was the adoption of defined go, no go criteria that removed the requirement for the pilot to make a judgement call in very time compressed and stressfull situation. Engine failure procedures were also refined so that the pilot flying did not do any actions that were not absolutely essential, and the importance of keeping the airplane under control is the paramount objective of the training.

So I asked myself how could I operate a light twin as close as possible to the proven methods of large aircraft ? I came to two conclusions for dealing with an engine failure at takeoff ( or any other circumstance where the ground is close ).

1) Light twins will only have the small amount of promised positive climb performance if the gear and flaps are up and the prop is feathering/feathered the airspeed is at the blueline value. Therefore any attempt to try to continue without all these criteria existing, probably will not be succesfull and therefore the automatic reaction should be to close both throttles and land straight ahead.

2) Therefore for a normal takeoff I will use zero flap and keep my fingers only on the throttles. After lift off and positive rate I will select gear up. When the the aircraft has accelerated to blue line I will remove my fingers from the throttles and put it on the prop levers. If there was an engine failure signalled by the rapid yaw I will move the prop lever in the direction of the yaw to the feahterd poistion set a slight nose up attitude and concentrate on flying the aircraft straight and maintaining a positive rate of climb

The bottom line is the position of my hand dictates my actions. If it is still on the throttles then I will retard both throttles and land ahead, if it is on the prop levers than I will feahter the engine and continue to fly

I mentioned in an earlier post about why I liked the vg equiped Cessna 340. It has a 100 kt blue line which allows a 100 kt V1 and VR. Except for the very few seconds between lift off, positive rate, selecting the gear up and moving your hands from throttles to props there is no ambiguity you either stop or are in apoistion to continue flight.

Finally I am not suggesting this is the only or even the best way to operate a light twin. I am sure there are pilots out there that could and have flown away from EFATO's well below blueline by cleaning up the airplane, feathering the prop and getting it to accelaerate and climbing away. Maybe on a good day I could do it but I feel more comforable that I would survive even on my worst day using this method. If that meant I wrote off the airplane sliding off the end of he runway when maybe I could have made it go.... well that is a risk I will accept.

[767]

many under-skilled pilots are not teaching because they are good at it, or even because they enjoy it, but only in order to build hours to get to another job. Nobody is going to be very good at their job if the only reason they are doing it is as a stepping stone to get somewhere else.

I see that every single day, pretty much all the flight schools.

[jetflightinstructor]

When we speak about creativity.... :

1) Light twins will only have the small amount of promised positive climb performance if the gear and flaps are up and the prop is feathering/feathered the airspeed is at the blueline value. Therefore any attempt to try to continue without all these criteria existing, probably will not be succesfull and therefore the automatic reaction should be to close both throttles and land straight ahead.

2) Therefore for a normal takeoff I will use zero flap and keep my fingers only on the throttles. After lift off and positive rate I will select gear up. When the the aircraft has accelerated to blue line I will remove my fingers from the throttles and put it on the prop levers. If there was an engine failure signalled by the rapid yaw I will move the prop lever in the direction of the yaw to the feahterd poistion set a slight nose up attitude and concentrate on flying the aircraft straight and maintaining a positive rate of climb

That is an idea...maybe a good one who knows.

But 2 points: no everybody does the same thing, which is pretty scarying,
second point is that I don' t think the EFATO procedure you describe is in accordance with a small twin AFM.

I feel more comforable that I would survive even on my worst day using this method

And me I feel it is dangerous to write procedures just following our feelings... I beleive in numbers, rate of climb, AFM, experience, training.

I am sure there are pilots out there that could and have flown away from EFATO's well below blueline by cleaning up the airplane, feathering the prop and getting it to accelaerate and climbing away

So that is a problem. the small twin pilots have to agreed on some "standard" procedure.

If that meant I wrote off the airplane sliding off the end of he runway when maybe I could have made it go.... well that is a risk I will accept.

There is not such a risk that we can accept. Training, and before flight calculation should be the answer.

For example: would you accept to take off with a twin knowing that the day you fly, you will have NO POSITIVE CLIMB in case of engine out?
Would you accept that, close the throttles and crash in front of you? Or just change the weight of the airplane, or cancel the flight?

I am not trying to be against you here, your post can give some good idea. I just think this is an interesting subject and like to know your opinion on what I ask.

[Big Pistons Forever]

jetflightinstructor: I fully agree that a full understanding of the available performance should be determined before the throttles go up. Unfortuantely the certainties offerd in Part 25 aircraft operations are not available in small twins. With respect to my post above I believe this proceedure provides the highest likelyhood of success but it certainly does not guarantee it. If the takeoff is continued the most important thing you will do is after completeing the drills maintain blueline. If the aircraft will not climb then you have no choice but to close both throttles and land.

Unfortunatly there is no certification requirement for light twins to able to survive an engine failure at any part of the takeoff. This makes it very difficult to have the one size fits all procedures you get in transport aircraft.

I also have found that many light twin POH's are not very usefull in getting a full appreciation of the possibilties for any one set off takeoff conditions. The most usefull chart I ever saw was a home grown one for a light unturbocharged twin. It distilled the single engine climb performance to a table. You go to the temp on one side and the field elevation on the bottom. The intersection is the max takeff weight which will give a 200 FPM climb. any takeoff weight above this figure and you are feffectively flying a single untill you are at least 500 ft AAE.

Finaly jetflightinstructor I would appreciate if you would describe how you handle the EFATO issue. Please describe the specific actions you will take at each part of the takeoff. I am asking because I am looking for other opinions on how to handle this situation in the hope I may be able to improve my own flying techniques.