FLIGHT SAFETY article "Twin Trouble"
Grandpa Aerotart
Unfortunately ?... you can't put an old head on young shoulders.
I can't give you a name who will roll it all into a neat package and then say "off you go my son"...I doubt anyone can.
What's your background, why do you want it?
There's an ATO on the Gold Coast, who I have flown with, who strikes me as the type of guy you're looking for...or who could point you there...I have heard very good things about a guy in TL but I'm not certain he has the bit of paper that says he can give ME Training Approval Training.
It's a combination of real experience in a variety of ME aircraft in varying rolls and an enquiring mind...with those two variables sorted the actual 'doing it', ie C&T, part is not difficult...if you have the knack for teaching to begin with.
Chuck.
I can't give you a name who will roll it all into a neat package and then say "off you go my son"...I doubt anyone can.
What's your background, why do you want it?
There's an ATO on the Gold Coast, who I have flown with, who strikes me as the type of guy you're looking for...or who could point you there...I have heard very good things about a guy in TL but I'm not certain he has the bit of paper that says he can give ME Training Approval Training.
It's a combination of real experience in a variety of ME aircraft in varying rolls and an enquiring mind...with those two variables sorted the actual 'doing it', ie C&T, part is not difficult...if you have the knack for teaching to begin with.
Chuck.
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I can recommend Gordon Smith at Armidale (Aircrew Check & Training) who can do ME Training approvals as well as pretty much anything else associated with aviation up to and including Biz Jet ratings. He has bases in Armidale & SE Qld - 02 67715582.
Re the topic of 'Blue Line'; reading most texts and journal articles will lead the average pilot to believe that if they don't simultaneously nail blue line speed, PLUS Mix/Pitch/Power max, PLUS gear & Flaps up, PLUS wings 5 degree bank into live engine, PLUS ball in the middle, PLUS Identify/Verify/Feather/Secure....then they are doomed to become a smoking hole in a nearby paddock.
At the time I swore to myself that I would never divulge this, but to put a human angle on this topic - here it is:
When I did my endorsement for the Aztec, I literally stepped out of the left seat of a large turbine twin into the 'new' aeroplane. A takeoff, followed by a bit of airwork, then a few circuits and assy work. On the first deliberate EFATO (at sea level + 300' ) I went automatically into the immediate actions and was very happy with my smooth management and the resultant 500'pm SE climb; then on starting the second phase I noticed the C&T guy in the RHS looking at me a bit oddly....until I found that that on checking that the autofeather had functioned correctly I remembered that this aeroplane didn't HAVE autofeather
So here we are in a light twin, blue line + 10kt IAS, climbing through 1000' at 500'/min, with one fan windmilling...........oops.
........but the point is, we DIDN'T automatically and instantly turn into a tangled mess of twisted aluminium. There IS a degree of fudge factor built into the specs....although I wouldn't recommend the same procedure at, say, LRE on a 4500' DA day.
Re the topic of 'Blue Line'; reading most texts and journal articles will lead the average pilot to believe that if they don't simultaneously nail blue line speed, PLUS Mix/Pitch/Power max, PLUS gear & Flaps up, PLUS wings 5 degree bank into live engine, PLUS ball in the middle, PLUS Identify/Verify/Feather/Secure....then they are doomed to become a smoking hole in a nearby paddock.
At the time I swore to myself that I would never divulge this, but to put a human angle on this topic - here it is:
When I did my endorsement for the Aztec, I literally stepped out of the left seat of a large turbine twin into the 'new' aeroplane. A takeoff, followed by a bit of airwork, then a few circuits and assy work. On the first deliberate EFATO (at sea level + 300' ) I went automatically into the immediate actions and was very happy with my smooth management and the resultant 500'pm SE climb; then on starting the second phase I noticed the C&T guy in the RHS looking at me a bit oddly....until I found that that on checking that the autofeather had functioned correctly I remembered that this aeroplane didn't HAVE autofeather
So here we are in a light twin, blue line + 10kt IAS, climbing through 1000' at 500'/min, with one fan windmilling...........oops.
........but the point is, we DIDN'T automatically and instantly turn into a tangled mess of twisted aluminium. There IS a degree of fudge factor built into the specs....although I wouldn't recommend the same procedure at, say, LRE on a 4500' DA day.
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This has been a very interesting thread. But we are all still stuck on this airspeed thing......... I agree that most GA aircraft don't have Angle of Attack indicators but the angle of attack is important in all of this debate.....
Now I am sure that plenty of people will correct me if I'm wrong.
Vy is the speed that produces the best rate of climb. This speed relates to the angle of attack that produces the best Lift/Drag ratio for the aircraft, this is achieved at an angle of attack of approximately 4 degrees and the speed varies.... But rate of climb is then also dependent on excess power......... Something we loose a lot of in a engine failure of a multi engine aircraft.
If you want to gain height in minimum time then climb at Vy.......
Now Vx is the speed that produces the best angle of climb. This speed relates to an angle of attack that produces minimum drag..... But why minimum drag???? because it is excess thrust that gives us angle of climb, rather than excess power..... Again a lot of thrust is lost when you suffer an engine failure.....
If you want to gain height for them minimum distance travelled then climb at Vx......
So therefore regardless of whether you are climbing on one engine or two.....
If you want to clear an obstacle after take off, climb at the airspeed that relates to the angle of attack that gives you Vx.
If you want to gain height quickly climb at the airspeed that relates to the angle of attack that gives you Vy.
Remember that the airspeed indicator is a poor mans angle of attack indicator. It is the angle of attack that is the important factor with regards to the airframe when considering performance with limited thrust or power
Two basic important things should be remember in a Engine failure after take off
1. Control the aircraft. Vyse and Vxse has nothing to do with this. People die in engine failures after take off because they loose control. If you can't control the aircraft you will die.
2. Performance. Once you have control and if lucky enough have feather the engine. The next question should be is the aircraft performing? You won't be able to assess this if you don't have control. If it is performing what do I want to do????? If it is me get back on the bloody ground safely. So I use Vx to avoid obstacles and Vy to climb to a safe height.
Now I am sure that plenty of people will correct me if I'm wrong.
Vy is the speed that produces the best rate of climb. This speed relates to the angle of attack that produces the best Lift/Drag ratio for the aircraft, this is achieved at an angle of attack of approximately 4 degrees and the speed varies.... But rate of climb is then also dependent on excess power......... Something we loose a lot of in a engine failure of a multi engine aircraft.
If you want to gain height in minimum time then climb at Vy.......
Now Vx is the speed that produces the best angle of climb. This speed relates to an angle of attack that produces minimum drag..... But why minimum drag???? because it is excess thrust that gives us angle of climb, rather than excess power..... Again a lot of thrust is lost when you suffer an engine failure.....
If you want to gain height for them minimum distance travelled then climb at Vx......
So therefore regardless of whether you are climbing on one engine or two.....
If you want to clear an obstacle after take off, climb at the airspeed that relates to the angle of attack that gives you Vx.
If you want to gain height quickly climb at the airspeed that relates to the angle of attack that gives you Vy.
Remember that the airspeed indicator is a poor mans angle of attack indicator. It is the angle of attack that is the important factor with regards to the airframe when considering performance with limited thrust or power
Two basic important things should be remember in a Engine failure after take off
1. Control the aircraft. Vyse and Vxse has nothing to do with this. People die in engine failures after take off because they loose control. If you can't control the aircraft you will die.
2. Performance. Once you have control and if lucky enough have feather the engine. The next question should be is the aircraft performing? You won't be able to assess this if you don't have control. If it is performing what do I want to do????? If it is me get back on the bloody ground safely. So I use Vx to avoid obstacles and Vy to climb to a safe height.
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Jamair
And that my friend is exactly the point, it is only "fudge" at ISA temps because of the bit of extra HP required to satisfy other certification requirements.
As you know FAR 25 does not have "fudge" it is a "requirement".
The unititiated think that because it has two then all is well.
BIK_116.80 as usual gets it exactly right.
Yo, Stallie thanks for your kind words but I did not invent the ideas, some very experienced and well informed "intructors and checkies" that I had the privilege to sit beside and generated an intense interest n the subject with me, can be thanked for my education and I feel an obligation to pass it on.
I've actually had people say to me in the past , if you are trying to sell these light twins, then why are you "carrying on like this"?
There IS a degree of fudge factor built into the specs....although I wouldn't recommend the same procedure at, say, LRE on a 4500' DA day.
As you know FAR 25 does not have "fudge" it is a "requirement".
The unititiated think that because it has two then all is well.
BIK_116.80 as usual gets it exactly right.
Yes I know that many CAR 3 / FAR 23 aircraft can easily exceed this minimum certification standard given certain weight and airfield conditions. It should be rather obvious to all concerned that the longer the runway and the lighter the load the greater the chance that an engine failure event might result in a successful outcome.
But any fancy ideas beyond that are the mental equivalent of changing deck chairs on the Titanic. Sure it might make you feel good - but in the end it isn't going to make any significant difference. These airplanes are simply not built for it.
These aircraft have two engines because they need two engines - not so that they have a spare one.
If you fly these aircraft around thinking that they might have an engine failure at any time then you are destined to be disappointed.
These aircraft come with two engines. I strongly suggest that you use both of them....ALL THE TIME.
.
But any fancy ideas beyond that are the mental equivalent of changing deck chairs on the Titanic. Sure it might make you feel good - but in the end it isn't going to make any significant difference. These airplanes are simply not built for it.
These aircraft have two engines because they need two engines - not so that they have a spare one.
If you fly these aircraft around thinking that they might have an engine failure at any time then you are destined to be disappointed.
These aircraft come with two engines. I strongly suggest that you use both of them....ALL THE TIME.
.
I've actually had people say to me in the past , if you are trying to sell these light twins, then why are you "carrying on like this"?
Like the joke says: Why do light twin engine a/c have two engines?
Because they need both of them...
Wagit, I'm sure we all realise that using IAS is really a second level approximation of what really counts ie AoA, but without direct access to an AoA indicator trying to define performance in accordance with AoA is meaningless. So, we have to be stuck on the airspeed. Without an AoA it's only instrument left to set a critical performance parameter - even if it is just an approximation.
On another matter, it's interesting the perception that 5deg bank is a performance issue when it's really a control issue.
5deg bank is set as a limit in the rules otherwise the manufacture can demonstrate astonishingly low Vmc speeds, upon which other speeds (not Vx's & Vy's) are dependent.
J Chesterfield at Coolangatta has maintained for years that the best performance AoB is around 2-3 deg in typical light twins. I did an aviation physics course years ago & could show the same thing mathmatically. Can't anymore because I....er....um....have forgotten how.
Because they need both of them...
Wagit, I'm sure we all realise that using IAS is really a second level approximation of what really counts ie AoA, but without direct access to an AoA indicator trying to define performance in accordance with AoA is meaningless. So, we have to be stuck on the airspeed. Without an AoA it's only instrument left to set a critical performance parameter - even if it is just an approximation.
On another matter, it's interesting the perception that 5deg bank is a performance issue when it's really a control issue.
5deg bank is set as a limit in the rules otherwise the manufacture can demonstrate astonishingly low Vmc speeds, upon which other speeds (not Vx's & Vy's) are dependent.
J Chesterfield at Coolangatta has maintained for years that the best performance AoB is around 2-3 deg in typical light twins. I did an aviation physics course years ago & could show the same thing mathmatically. Can't anymore because I....er....um....have forgotten how.
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?... Wagit etc
Want to find the right instructor?
Firstly, stay away from the sausage factories, their experience is usually limited to ideal conditions ( BIG sealed runways, ISA conditions and minimum takeoff weights).
For the very best, try Lester Niedeck at Sunshine Coast Air Charter, Caloundra, before he retires. Lester teaches "Attitude Flying", based on the premise that "Power plus Attitude plus Configuaration equals performance. Nothing magic about this but it is alien to the "chase the airspeed till blue-line" crowd.
He will actually teach you to set all the parameters to get the performance you want i.e. Blue Line.
He will also teach you about banking to the live engine and zero sideslip in phase two of the drills and you will actually see for yourself the difference.
Lester also teaches workload minimisation for the single pilot IFR workload environment and generally how to make things happen as opposed to watching things happen. I am still alive as a result of his thorough training after suffering a broken crankshaft in IMC.
As a matter of statistic, none of his trainees have killed themselves yet in IFR operations.
You might also try, as suggested, Gordon Smith or John Chesterfield. Both very good at what they produce.
As for Airspeed indicators, they have two inherent problems in the takeoff phase, (i) they have lag ( hysteresis) and (ii) they under read whilst in ground effect ( study what you can on all aspects of Ground Effect to see that pressure instruments are affected in ground effect). When you see the speed you're looking for, you've actually just gone past it, a bonus for you.
Whilst you don't normally have an AoA indicator in GA aircraft, you do have an ATTITUDE Indicator ( Artificial Horizon). This instrument does not have lag and can be used to accurately set a predetermined attitude that will deliver a predictable PERFORMANCE.
As for the article that prompted this thread, the author will have no problems with safety as long as he sticks to his long sealed runways at ISA and sea level. HOWEVER, when he operates where most of us ply our trade ( less than 1,000 metres, ISA +25, wet grass or dry sand/gravel, above sea level) he is bound to make the pages of an ATSB report.
to summarise:
POWER i Both engines operating at takeoff power or one operating at take off power and one windmilling
ATTITUDE : The correct predetermined attitude for either both engines operating or for one engine inoperative ( two different attitudes)
CONFIGURATION : Gear and flap up or retracting
EQUALS
Performance : Vxse or Vyse, whichever you set the attitude for will be guaranteed. If not exactly where you want it, adjust the ATTITUDE slightly to attain it
How many accidents could have been avoided if this common sense approach had been taught to all multi pilots ?
And yes, the bank to the live engine with zero sideslip will optimise the rate of climb and is verifiable in most charter aircraft, but not always in lighter training twins ( Seminole/Duchess).
Want to find the right instructor?
Firstly, stay away from the sausage factories, their experience is usually limited to ideal conditions ( BIG sealed runways, ISA conditions and minimum takeoff weights).
For the very best, try Lester Niedeck at Sunshine Coast Air Charter, Caloundra, before he retires. Lester teaches "Attitude Flying", based on the premise that "Power plus Attitude plus Configuaration equals performance. Nothing magic about this but it is alien to the "chase the airspeed till blue-line" crowd.
He will actually teach you to set all the parameters to get the performance you want i.e. Blue Line.
He will also teach you about banking to the live engine and zero sideslip in phase two of the drills and you will actually see for yourself the difference.
Lester also teaches workload minimisation for the single pilot IFR workload environment and generally how to make things happen as opposed to watching things happen. I am still alive as a result of his thorough training after suffering a broken crankshaft in IMC.
As a matter of statistic, none of his trainees have killed themselves yet in IFR operations.
You might also try, as suggested, Gordon Smith or John Chesterfield. Both very good at what they produce.
As for Airspeed indicators, they have two inherent problems in the takeoff phase, (i) they have lag ( hysteresis) and (ii) they under read whilst in ground effect ( study what you can on all aspects of Ground Effect to see that pressure instruments are affected in ground effect). When you see the speed you're looking for, you've actually just gone past it, a bonus for you.
Whilst you don't normally have an AoA indicator in GA aircraft, you do have an ATTITUDE Indicator ( Artificial Horizon). This instrument does not have lag and can be used to accurately set a predetermined attitude that will deliver a predictable PERFORMANCE.
As for the article that prompted this thread, the author will have no problems with safety as long as he sticks to his long sealed runways at ISA and sea level. HOWEVER, when he operates where most of us ply our trade ( less than 1,000 metres, ISA +25, wet grass or dry sand/gravel, above sea level) he is bound to make the pages of an ATSB report.
to summarise:
POWER i Both engines operating at takeoff power or one operating at take off power and one windmilling
ATTITUDE : The correct predetermined attitude for either both engines operating or for one engine inoperative ( two different attitudes)
CONFIGURATION : Gear and flap up or retracting
EQUALS
Performance : Vxse or Vyse, whichever you set the attitude for will be guaranteed. If not exactly where you want it, adjust the ATTITUDE slightly to attain it
How many accidents could have been avoided if this common sense approach had been taught to all multi pilots ?
And yes, the bank to the live engine with zero sideslip will optimise the rate of climb and is verifiable in most charter aircraft, but not always in lighter training twins ( Seminole/Duchess).
Last edited by Mainframe; 25th Apr 2003 at 10:08.
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Mainframe, Chimbu and Wagit...
Thanks, those references have been a great help.
Chimbu quite correct on saying you can't put an old head on young shoulders, but that is why I asked this very question, what I may lack in experience
I can somewhat make up for in enthusiasm and thirst for knowledge 
Why do I want it? Because I want to learn as much as I can about how to fly twins safely and efficently in a more thorough and indepth way than I can remember about my Initial Twin. This is only a reasonable request that passenegers deserve to feel that their pilot knows what he/she is doing.
Cheers All and Safe Flying
Chimbu quite correct on saying you can't put an old head on young shoulders, but that is why I asked this very question, what I may lack in experience
I can somewhat make up for in enthusiasm and thirst for knowledge Why do I want it? Because I want to learn as much as I can about how to fly twins safely and efficently in a more thorough and indepth way than I can remember about my Initial Twin. This is only a reasonable request that passenegers deserve to feel that their pilot knows what he/she is doing.
Cheers All and Safe Flying
Lester retiring! What a shame.
I did my CIR with him 15 yrs ago. Very recommended. Does he still use that Seneca 1? VH-SMM, I think?
I did my CIR with him 15 yrs ago. Very recommended. Does he still use that Seneca 1? VH-SMM, I think?
Last edited by Tinstaafl; 26th Apr 2003 at 21:53.
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Tinstaafl
Stated:
On another matter, it's interesting the perception that 5deg bank is a performance issue when it's really a control issue.
I agree!!!!!!!!!!
There is a benefit for the 5 degrees angle of bank and that is it reduces drag.....
Mainframe
Thanks for the tip with regards to your twin instructor and I agree with what you are saying, but don't fall into the fatal trap that attitude of an aircraft is the same as angle of attack. Because you can have a different nose attitude but the same angle of attack........
Stated:
On another matter, it's interesting the perception that 5deg bank is a performance issue when it's really a control issue.
I agree!!!!!!!!!!
There is a benefit for the 5 degrees angle of bank and that is it reduces drag.....
Mainframe
Thanks for the tip with regards to your twin instructor and I agree with what you are saying, but don't fall into the fatal trap that attitude of an aircraft is the same as angle of attack. Because you can have a different nose attitude but the same angle of attack........
Moderator
Wagit, good sir ...
I suspect that you need to re-read the earlier posts regarding bank angle as you appear to have misinterpreted those comments.
(a) the 5 degree thing relates to Vmc determination and is a limitation (ie max bank angle permitted) imposed by the Design Standards. It relates to a handling matter rather than climb performance ...
(b) best OEI climb performance, other things being equal, will occur with zero sideslip (recall how you cause a single on a high approach to increase the flight path angle - you introduce an intentional slip - slip increases overall drag and increases descent/reduces climb performance)
Most aircraft (from bugsmasher twins to widebodies - however many motors ...) will achieve zero sideslip somewhere about 2-3 degrees bank into the operating engines which should be the target bank angle if you are out to achieve those last few FPM.
With the climb performance at 5 degrees being somewhat similar to that achieved wings level (similar sideslip but in opposite directions), why bother with 5 degrees when it is easier to fly wings level ?
A Tech Log thread on V2 Cuts is quite relevant reading. It is worth noting that several of the participants in that thread are/were heavyweights in the design and flight test community and their observations carry significant weight
Then again, a Concorde pilot just follows the gauge which tells you the bank angle to fly for best performance .....
I suspect that you need to re-read the earlier posts regarding bank angle as you appear to have misinterpreted those comments.
(a) the 5 degree thing relates to Vmc determination and is a limitation (ie max bank angle permitted) imposed by the Design Standards. It relates to a handling matter rather than climb performance ...
(b) best OEI climb performance, other things being equal, will occur with zero sideslip (recall how you cause a single on a high approach to increase the flight path angle - you introduce an intentional slip - slip increases overall drag and increases descent/reduces climb performance)
Most aircraft (from bugsmasher twins to widebodies - however many motors ...) will achieve zero sideslip somewhere about 2-3 degrees bank into the operating engines which should be the target bank angle if you are out to achieve those last few FPM.
With the climb performance at 5 degrees being somewhat similar to that achieved wings level (similar sideslip but in opposite directions), why bother with 5 degrees when it is easier to fly wings level ?
A Tech Log thread on V2 Cuts is quite relevant reading. It is worth noting that several of the participants in that thread are/were heavyweights in the design and flight test community and their observations carry significant weight
Then again, a Concorde pilot just follows the gauge which tells you the bank angle to fly for best performance .....
Last edited by john_tullamarine; 26th Apr 2003 at 22:37.
Wagit,
If you've interpreted my comments to mean that 5deg bank gives maximum performance, then I've not been clear enough.
5deg AoB is a control parameter, NOT a single engine performance one. During certification, 5 deg bank is set as a limit to determine Vmc. That's unrelated to s.e. performance.
Max performance does not equate to 5 deg bank. More like a couple of degrees.
If you've interpreted my comments to mean that 5deg bank gives maximum performance, then I've not been clear enough.
5deg AoB is a control parameter, NOT a single engine performance one. During certification, 5 deg bank is set as a limit to determine Vmc. That's unrelated to s.e. performance.
Max performance does not equate to 5 deg bank. More like a couple of degrees.
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john_tullamarine and Tinstaafl
I understand that 5 degrees of bank is related to control and VMCa.
But there is an added benefit too.
Let say you are climbing single engine with out 5 degree angle of bank towards the live engine (i.e. raising the dead engine). How much drag is the airframe producing as compared to an aircraft that is climbing single engine with 5 degrees of angle of bank towards the live engine??????
I understand that 5 degrees of bank is related to control and VMCa.
But there is an added benefit too.
Let say you are climbing single engine with out 5 degree angle of bank towards the live engine (i.e. raising the dead engine). How much drag is the airframe producing as compared to an aircraft that is climbing single engine with 5 degrees of angle of bank towards the live engine??????
We're not talking about 5 deg bank away from the live engine. It's accepted that bank away from the live engine while maintaining a constant heading rapidly reduces performance capability. We're comparing wings level through to 5 deg bank towards the live engine.
There isn't an added benefit using 5deg AoB apart from Vmc limits. The max performance benefit occurs at ~2-3 deg. The asymmetric min drag curve bottoms out at that angle. More than that & you're adding drag compared to the min drag AoB (ie ~2-3 deg). At 5 deg AoB drag is about the same as wings level so why bother?
Unless you have a control problem ie are near, at or below Vmc then there's no gain to flying at 5 deg - or more - AoB. You're better off maintaining wings level & reducing at least one item of task loading.
NB: I'll backtrack on the 'no reason' above: If you want to relieve some/all of the residual rudder pressure even after trimming. It will be at the expense of performance capability though.
-------------------
Just re-read Wagit's post. I thought the last paragraph was comparing a 5deg AoB away from the live engine, to a 5deg AoB towards the live engine.
On re-reading I see I misinterpreted that paragraph. Both of its sentences are the same ie mention an AoB towards the live engine.
Have I missed something?
There isn't an added benefit using 5deg AoB apart from Vmc limits. The max performance benefit occurs at ~2-3 deg. The asymmetric min drag curve bottoms out at that angle. More than that & you're adding drag compared to the min drag AoB (ie ~2-3 deg). At 5 deg AoB drag is about the same as wings level so why bother?
Unless you have a control problem ie are near, at or below
Vmc then there's no gain to flying at 5 deg - or more - AoB. You're better off maintaining wings level & reducing at least one item of task loading. NB: I'll backtrack on the 'no reason' above: If you want to relieve some/all of the residual rudder pressure even after trimming. It will be at the expense of performance capability though.
-------------------
Just re-read Wagit's post. I thought the last paragraph was comparing a 5deg AoB away from the live engine, to a 5deg AoB towards the live engine.
On re-reading I see I misinterpreted that paragraph. Both of its sentences are the same ie mention an AoB towards the live engine.
Have I missed something?
Last edited by Tinstaafl; 29th Apr 2003 at 00:11.
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Col.
Took the words right out of my mouth, you are, for the most part, simply trying to achieve the least worst result
Mornin john_t cha's up.
Took the words right out of my mouth, you are, for the most part, simply trying to achieve the least worst result
Mornin john_t cha's up.
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Aircraft Control
Performance
Obstacles
The plan you initiate after a failure and decide to “GO” rather than abort is dependant upon the above, IMHO in that order of priority, there are other side issues but they are the basics.
Having not read the magazine article yet, it does not sound like a very good plan for dealing with an EFATO scenario. The posts that I have read through show a range of diverse thinking and theorising on the subject, some on the fringe of being potentially unsafe.
Several things that I have been taught in flying light twins are:
1. To apply a reaction factor to the S/E performance speeds i.e. 5/10 kts based on your flying skills. Otherwise you will need to trade height to get the speeds you need.
2. Adopt a wings level attitude until you have complete control, then apply the bank – the result will increase climb performance but it is only VERY marginal.
3. Have a plan, and be prepared to modify it if necessary.
4. Remember, that the failure that you get in reality is rarely anything like the ones you have had in practice.
Controlling the aircraft is of the utmost importance- even if it is to the point of impact, and I can still hear the chant, “…..only decide to GO if you believe you will do worse by aborting the T/O”.
And…………Good Luck..........light twins aren’t really designed at MTOW to do very well in the climb performance department when you loose one- I’m sure this is a well known fact though.
Performance
Obstacles
The plan you initiate after a failure and decide to “GO” rather than abort is dependant upon the above, IMHO in that order of priority, there are other side issues but they are the basics.
Having not read the magazine article yet, it does not sound like a very good plan for dealing with an EFATO scenario. The posts that I have read through show a range of diverse thinking and theorising on the subject, some on the fringe of being potentially unsafe.
Several things that I have been taught in flying light twins are:
1. To apply a reaction factor to the S/E performance speeds i.e. 5/10 kts based on your flying skills. Otherwise you will need to trade height to get the speeds you need.
2. Adopt a wings level attitude until you have complete control, then apply the bank – the result will increase climb performance but it is only VERY marginal.
3. Have a plan, and be prepared to modify it if necessary.
4. Remember, that the failure that you get in reality is rarely anything like the ones you have had in practice.
Controlling the aircraft is of the utmost importance- even if it is to the point of impact, and I can still hear the chant, “…..only decide to GO if you believe you will do worse by aborting the T/O”.
And…………Good Luck..........light twins aren’t really designed at MTOW to do very well in the climb performance department when you loose one- I’m sure this is a well known fact though.
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Agree with mainframe...
You cannot set an airspeed by chasing the needles, by the time you see blueline indicated the aircraft has accelerated to a higher speed due to lag in the ASI... same applies to the VSI.
It's very simple physics.. set an attitude and a power setting, with a certain aircraft configuration, and the aircraft MUST achieve a certain level of performance.
An analogy I was given when training: think about driving a car up a hill - for a certain gradient and throttle setting a certain speed will be achieved. In an aeroplane the gradient is set by attitude.
So my normal takeoff in a light twin is at Vr to rotate the aircraft to 5 degrees nose up, once airborne with positive rate of climb or insufficient runway, whatever I decide, select gear up and attitude to at least 8 degrees (1 degree per wheel)... Vyse will look after itself. Vx can be found at about 10 degrees. The attitudes may need some adjusting depending on aircraft type, weight and ambient conditions etc. Once at a safe height back to 5 degrees nose up and accelerate into a cruise climb. I use the VSI and ASI to cross check performance only, the AI is the primary instrument. Works particularly well at night or in IMC... just remember to set the AI correctly!
These attitudes work with only small variations on all the light twins I have flown, and is the method I was taught at my initial multi.
You cannot set an airspeed by chasing the needles, by the time you see blueline indicated the aircraft has accelerated to a higher speed due to lag in the ASI... same applies to the VSI.
It's very simple physics.. set an attitude and a power setting, with a certain aircraft configuration, and the aircraft MUST achieve a certain level of performance.
An analogy I was given when training: think about driving a car up a hill - for a certain gradient and throttle setting a certain speed will be achieved. In an aeroplane the gradient is set by attitude.
So my normal takeoff in a light twin is at Vr to rotate the aircraft to 5 degrees nose up, once airborne with positive rate of climb or insufficient runway, whatever I decide, select gear up and attitude to at least 8 degrees (1 degree per wheel)... Vyse will look after itself. Vx can be found at about 10 degrees. The attitudes may need some adjusting depending on aircraft type, weight and ambient conditions etc. Once at a safe height back to 5 degrees nose up and accelerate into a cruise climb. I use the VSI and ASI to cross check performance only, the AI is the primary instrument. Works particularly well at night or in IMC... just remember to set the AI correctly!
These attitudes work with only small variations on all the light twins I have flown, and is the method I was taught at my initial multi.
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Mr Whippy
Well done that man.
and it doesn't just apply to light twins either.
I'll have one of your double cones with choccy topping and nuts please.
Well done that man.
and it doesn't just apply to light twins either.I'll have one of your double cones with choccy topping and nuts please.
What's this - a TechLog discuaaion outside Techlog?? Good thing I just stumbled onto it!
Multi-engine aircraft are divided by FAR 23 into two weight classes - above and below 6000lbs, and those below 6000lbs are divided into two classes depending on Vso (stall speed in the landing configuration) above and below 61 knots CAS.
Only those twins that weigh more than 6000lbs or have a Vso higher than 61 knots need to demonstrate any single-engine climb performance at all for certificaion, and the requirements are pretty meager. Basically the regulation says that these aircraft must demonstrate a single engine capability at 5000' (ISA) with the inop engine feathered and in a clean configaration.
The only requirement for an aircraft less than 6000lbs, and with a Vso less than 61kts (like the Aztec) is that its climb performance (positive or negative) be determined.
There is nothing in the FAR which says an aircraft must fly while in the take-off configuration with one engine inop.
Talking about rotation, manufacturers tend to have a philosophy about this that shows up in in the aircraft design, wing incidence and gear positioning.
Piper recommends that most twins be rotated at Vmc, Cessna on the other hand suggests a lift off at a speed much higher than Vmc and very close to best single-engine angle of climb speed. In the case of a C-310, Vmc is 75 knots, recommended rotation speed is 91 knots and best single engine angle of climb speed is 94.
Try and hold a Seneca or Aztec on the ground much beyond Vmc plus 5 knots (zero flap) and the aircraft will begin to wheelbarrow! Cessna twins (and most cabin class twins) will happily stay on the ground for much longer than that.
A Navajo for instance (stretching the old memory) will happily go by road, if you don't positively rotate it - you hardly have to "force the aircraft on the runway well past VR and until a few knots past Blue Line"!
I would rotate a light (FAR 23) twin not below Vmc+5 (or the recommended rotate), and I pull the gear up just after getting airbourne, then climb at the best all engine climb rate (which is faster then blue line) until clear of obstacles in the area.
(Information from an old post of mine - some of the "more established" members may remember it. It was called something like "Blue Line Speed in light Twins" on the old Dunnunder, but I can't find it now.)
P.S. It's damned annoying that they don't have good soft icecream here in the UK. Apart from the poor icecream, if you ask for chocolate, you get chocolate sauce, not hard chocolate!
Is it only warmer countries that do decent icecream?
Multi-engine aircraft are divided by FAR 23 into two weight classes - above and below 6000lbs, and those below 6000lbs are divided into two classes depending on Vso (stall speed in the landing configuration) above and below 61 knots CAS.
Only those twins that weigh more than 6000lbs or have a Vso higher than 61 knots need to demonstrate any single-engine climb performance at all for certificaion, and the requirements are pretty meager. Basically the regulation says that these aircraft must demonstrate a single engine capability at 5000' (ISA) with the inop engine feathered and in a clean configaration.
The only requirement for an aircraft less than 6000lbs, and with a Vso less than 61kts (like the Aztec) is that its climb performance (positive or negative) be determined.
There is nothing in the FAR which says an aircraft must fly while in the take-off configuration with one engine inop.
Talking about rotation, manufacturers tend to have a philosophy about this that shows up in in the aircraft design, wing incidence and gear positioning.
Piper recommends that most twins be rotated at Vmc, Cessna on the other hand suggests a lift off at a speed much higher than Vmc and very close to best single-engine angle of climb speed. In the case of a C-310, Vmc is 75 knots, recommended rotation speed is 91 knots and best single engine angle of climb speed is 94.
Try and hold a Seneca or Aztec on the ground much beyond Vmc plus 5 knots (zero flap) and the aircraft will begin to wheelbarrow! Cessna twins (and most cabin class twins) will happily stay on the ground for much longer than that.
A Navajo for instance (stretching the old memory) will happily go by road, if you don't positively rotate it - you hardly have to "force the aircraft on the runway well past VR and until a few knots past Blue Line"!
I would rotate a light (FAR 23) twin not below Vmc+5 (or the recommended rotate), and I pull the gear up just after getting airbourne, then climb at the best all engine climb rate (which is faster then blue line) until clear of obstacles in the area.
(Information from an old post of mine - some of the "more established" members may remember it. It was called something like "Blue Line Speed in light Twins" on the old Dunnunder, but I can't find it now.)
P.S. It's damned annoying that they don't have good soft icecream here in the UK. Apart from the poor icecream, if you ask for chocolate, you get chocolate sauce, not hard chocolate!
Is it only warmer countries that do decent icecream?