Merged: The multi engine debate.
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Merged: The multi engine debate.
One well informed gentleman in other posts has mentioned both CAAP 5.23-2 (0) and the FAA Airman's Handbook as valid multi engine training references.
The question "do they read their own material? " was asked. (Good one). I have been fairly reliably informed that certain operators have been told (nothing written) to remove briefing notes (FAA manual and CAAP) relating to safe OEI operations from operations/ training manuals?. Seems the FAA have no idea about OEI and the associated methods of teaching same.
The on going PA 31 saga would clearly indicate they do not read their own material; but this gets better. Apparently, this was the third go around of training these blokes have gone through. Seems that there was no "evidence" that "correct" asymmetric training was given during both the first and second lot of training. This is despite about a dozen blokes being recalled to ensure that asymmetric training was conducted and completed "to the satisfaction of" the instructor pilot, after the first training sessions were declared invalid.
It is rumoured that the final instructor pilot asked for directions on exactly what was meant, then politely but firmly declined the invitation to conduct mixture induced engine cuts at low speed and height. Bravo that man or woman. It seems that the use of a humble "Elite AT11 – I" was deemed as satisfactory for this exercise. There is nothing wrong with the Elite, neither the manufacturer or operator make claims that this device is any thing else except a very good, valuable training aid within it's certified limits.
The idea that it can accurately represent a PA 31 at MTOW weight with OEI is beyond a joke.
The notion that this exercise was any thing else but "negative training" borders on both reckless and negligent. IMHO I doubt that the exercise could even be legally claimed toward a type rating. Would they knock back a type rating conducted in this manner. You could just about bet the house on it.
The question "do they read their own material? " was asked. (Good one). I have been fairly reliably informed that certain operators have been told (nothing written) to remove briefing notes (FAA manual and CAAP) relating to safe OEI operations from operations/ training manuals?. Seems the FAA have no idea about OEI and the associated methods of teaching same.
The on going PA 31 saga would clearly indicate they do not read their own material; but this gets better. Apparently, this was the third go around of training these blokes have gone through. Seems that there was no "evidence" that "correct" asymmetric training was given during both the first and second lot of training. This is despite about a dozen blokes being recalled to ensure that asymmetric training was conducted and completed "to the satisfaction of" the instructor pilot, after the first training sessions were declared invalid.
It is rumoured that the final instructor pilot asked for directions on exactly what was meant, then politely but firmly declined the invitation to conduct mixture induced engine cuts at low speed and height. Bravo that man or woman. It seems that the use of a humble "Elite AT11 – I" was deemed as satisfactory for this exercise. There is nothing wrong with the Elite, neither the manufacturer or operator make claims that this device is any thing else except a very good, valuable training aid within it's certified limits.
The idea that it can accurately represent a PA 31 at MTOW weight with OEI is beyond a joke.
The notion that this exercise was any thing else but "negative training" borders on both reckless and negligent. IMHO I doubt that the exercise could even be legally claimed toward a type rating. Would they knock back a type rating conducted in this manner. You could just about bet the house on it.
It wasn't that long ago when both the very experienced flying instructor (30,000 hours)and his very experienced Boeing 767 captain "student" were both horribly burnt when the Duchess they were flying clipped trees shortly after take off and crashed at Camden. Both survived the wheels up landing but the instructor died of burns when the aircraft went through a fence and hit an iron girder part of farm machinary and caught fire. It was a "simulated" engine failure caused by a deliberate mixture cut. There is no shortage of documentary evidence that mixture cuts to simulate engine failure after lift off have caused fatal accidents.
Many years ago the NTSB warned of the dangers on simulated engine-out manoeuvres in a Bulletin that (edited for brevity) stated " The fatal crash of a light twin in which a flight instructor and an applicant for a multi-engine rating were killed prompted the NTSB to issue an urgent warning to all pilots simulating an engine-out condition on multi-engine aircraft...the boards investigation revealed that some flight instructors do use the mixture control or the fuel selector to shut down an engine to test a multi-engine applicant..
...the urgent warning was aimed at flight instructors who were using this procedure at altitudes too low for continued safe flight..the NTSB observed that use of such procedures at traffic pattern altitudes may not permit instructors enough time to overcome possible errors on the part of the applicant...
....the recommendation by the NTSB means that all simulated engine-out operations at the lower altitudes should be accomplished by retarding the throttle and this should be done slowly to avoid engine damage or failure...this careful technique will protect the engine, and at the same time provide for instant power if it is needed.
Any instructor that uses the mixture control to simulate an engine failure after take off is should be charged with reckless conduct.
Many years ago the NTSB warned of the dangers on simulated engine-out manoeuvres in a Bulletin that (edited for brevity) stated " The fatal crash of a light twin in which a flight instructor and an applicant for a multi-engine rating were killed prompted the NTSB to issue an urgent warning to all pilots simulating an engine-out condition on multi-engine aircraft...the boards investigation revealed that some flight instructors do use the mixture control or the fuel selector to shut down an engine to test a multi-engine applicant..
...the urgent warning was aimed at flight instructors who were using this procedure at altitudes too low for continued safe flight..the NTSB observed that use of such procedures at traffic pattern altitudes may not permit instructors enough time to overcome possible errors on the part of the applicant...
....the recommendation by the NTSB means that all simulated engine-out operations at the lower altitudes should be accomplished by retarding the throttle and this should be done slowly to avoid engine damage or failure...this careful technique will protect the engine, and at the same time provide for instant power if it is needed.
Any instructor that uses the mixture control to simulate an engine failure after take off is should be charged with reckless conduct.
This is a quote from most twin engine Piper Manuals;
This was added to the PA31 POH in 1976. You would be a brave (or stupid) individual to intentionally operate an aircraft in contravention to a manufacturers recomendations without strong evidence against such procedures.
Experience has shown that the training advantage gained by pulling a mixture control or turning off the fuel to simulate engine failure at low altitude is not worth the risk assumed. Therefore, it is recommended that instead of using either of these procedures to simulate loss of power at low altitude, the throttle be retarded slowly to idle position. Fast reduction of power may be harmful to the engine.
Wouldn't it be easier to ask how many people have ever had a problem getting an engine at idle power to full power as opposed to getting a shut down engine to start up?
I'll admit I don't have a lot of Multi Engine experience and nor am I more than a Rookie, but the hundreds of engine start ups i've conducted and seen done have taught me that a GA engine can be a b*tch to get started even at the best of times but I can't say i've ever had any issues when applying full power from idle.
Those simple facts should show that reducing the throttle instead of mixture to ICO is the better procedure when simulating OEI and it was certainly the standard when I did my Multi Endorsement.
And the part about reducing the throttle slowly, well once again, i've never had any issues when i've reduced a throttle slowly but i've certainly had some disagreements with engines when i've closed the throttle too fast.
Just seems like common sense doesn't it?
I'll admit I don't have a lot of Multi Engine experience and nor am I more than a Rookie, but the hundreds of engine start ups i've conducted and seen done have taught me that a GA engine can be a b*tch to get started even at the best of times but I can't say i've ever had any issues when applying full power from idle.
Those simple facts should show that reducing the throttle instead of mixture to ICO is the better procedure when simulating OEI and it was certainly the standard when I did my Multi Endorsement.
And the part about reducing the throttle slowly, well once again, i've never had any issues when i've reduced a throttle slowly but i've certainly had some disagreements with engines when i've closed the throttle too fast.
Just seems like common sense doesn't it?
The advice does not say don't use fuel or mixture to simulate, just use slow reduction of throttle at low altitude. You may use other methods at an appropriate height. The main aim is to not lose control at low altitude which may be caused by sudden power loss due to mixture or sudden throttle reduction.
Mixture leaning is at operators discretion, it impacts engine life and will not cause an aircraft to drop out of the sky if done properly. This includes maintenance procedures and continual monitoring of engine health. The aircraft manufacturer only provides information on how to lean for certain outcomes, best power, best economy etc... the one that provides best engine life is up to you and consultation with the engine manufacturer.
Mixture leaning is at operators discretion, it impacts engine life and will not cause an aircraft to drop out of the sky if done properly. This includes maintenance procedures and continual monitoring of engine health. The aircraft manufacturer only provides information on how to lean for certain outcomes, best power, best economy etc... the one that provides best engine life is up to you and consultation with the engine manufacturer.
Last edited by 43Inches; 2nd Aug 2010 at 12:34.
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Lads, don't worry about the width, feel the quality.
Mixture, throttle, throttle, mixture – not the issue. Hell, you pull the mixture on a GSO 480 or GSIO 540 and you are a dead man on the next flight. The donkeys in a twin comm don't care that much. The management of "your" engine will vary with many, many considerations. YOU should know what's best for the engine you operate.
Heating, cooling, perhaps an issue; super heat, super cool maybe an issue for the next bloke.
Lean of peak, rich of peak. Who bloody cares!. Operate the engines the way the grown ups (engineers) want it done (that's AFM certification SOP Joyce) and God willing, weather permitting, not too much trouble to be expected.
But you start buggering about at zot feet with nothing on the clock but a makers name and, soon or late your luck will run out. That is not IF - only when. QED.
Teach the children to 'nut out' safely stop or safely go parameters. The average bloke, confronted by the manufacturers numbers will very quickly work it out.
ASDR 1200 meters, TORR 870 meters, A- GO 1800 meters. (apologies to the purists).
Vmca 76, Vr 95, Vyse 104. Loose one and then find 9 knots from rotate to get to speed which is not guaranteed to give a positive rate of climb.
Borrowed this :- 'It is not that the aircraft cannot take off from a shorter distance, however, if the aircraft cannot SAFELY GO, logically, it must be able to SAFELY STOP". Next time you train a fellah, think about the desired result i.e. all at the bar talking about it, not being dragged in pieces, out of a burning wreck.
Tailwinds.
Heating, cooling, perhaps an issue; super heat, super cool maybe an issue for the next bloke.
Lean of peak, rich of peak. Who bloody cares!. Operate the engines the way the grown ups (engineers) want it done (that's AFM certification SOP Joyce) and God willing, weather permitting, not too much trouble to be expected.
But you start buggering about at zot feet with nothing on the clock but a makers name and, soon or late your luck will run out. That is not IF - only when. QED.
Teach the children to 'nut out' safely stop or safely go parameters. The average bloke, confronted by the manufacturers numbers will very quickly work it out.
ASDR 1200 meters, TORR 870 meters, A- GO 1800 meters. (apologies to the purists).
Vmca 76, Vr 95, Vyse 104. Loose one and then find 9 knots from rotate to get to speed which is not guaranteed to give a positive rate of climb.
Borrowed this :- 'It is not that the aircraft cannot take off from a shorter distance, however, if the aircraft cannot SAFELY GO, logically, it must be able to SAFELY STOP". Next time you train a fellah, think about the desired result i.e. all at the bar talking about it, not being dragged in pieces, out of a burning wreck.
Tailwinds.
Operate the engines the way the grown ups (engineers) want it done (that's AFM certification SOP Joyce) and God willing, weather permitting, not too much trouble to be expected.
No thanks, I'd rather operate them the way the manufacturer suggests.
No AS2A: I can't describe a 'throttle/fuel system on an aircraft where pulling the mixture would be safer or better than closing the throttle' That's not what I was suggesting. I was suggesting that on some aircraft, like mine, the risks of pulling the mixture are the same as pulling the throttle.
The probabilities of a mixture pull causing problems, and the nature of those problems, are the same as pulling the throttle, on the particular system fitted to my aircraft. I know that, because I know that the probabilities of each cable failing are the same, I know where each of those cable go, I know what each of those cable do, and I know what the consequences of each of those cables failing, or the things to which they are connected failing, are.
The probabilities of a mixture pull causing problems, and the nature of those problems, are the same as pulling the throttle, on the particular system fitted to my aircraft. I know that, because I know that the probabilities of each cable failing are the same, I know where each of those cable go, I know what each of those cable do, and I know what the consequences of each of those cables failing, or the things to which they are connected failing, are.
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Now, Mr Fanneli?
Q_ In the period leading up to 'your' accident, did you operate the aircraft engines according to the Aircraft Flight Manual specifications, for which the manufacturers data was approved?.
Your call Pete. (that's AFM certification SOP Joyce). Aircraft Flight Manual - Standard Operating Procedure.
Yes (then prove it) or NO, then justify it. Still your call.
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Only ever borrowed an engine
With respect Bushy - bollox.
Good LAME' s own each engine on the wing (and some that ain't).
Mishandle a pet engine at your p p p peril, but listen quietly and learn well the true art of actually managing your LAME' s engines and you may earn a cuppa and grudging smile at smoko.
Good LAME' s own each engine on the wing (and some that ain't).
Mishandle a pet engine at your p p p peril, but listen quietly and learn well the true art of actually managing your LAME' s engines and you may earn a cuppa and grudging smile at smoko.
It's just as easy to slowly reduce and increase power using the mixture control, on systems like the one fitted to my aircraft.
As you have said previously all aircraft are different, a slow reduction of mixture to cut-out at high power in a turbo-charged type may lead to excedance of the maximum permissible EGT.
The issue I have at low altitude is intentional sudden loss of power combined with poor response from the student and instructor leading to loss of control. This could be induced either by sudden throttle reduction or mixture cut. Even rapid re-application of power may not save the situation if low enough. The Piper extract shows that it was a consideration back in the 70's after numerous accidents during low level assymetric operations. They determined (FAA and piper followed) the safest course of action was to simulate failure at low level by slowly reducing throttle and that there was negligible reduction in learning outcome as a result.
Provide solid proof that this technique is not sound in all light twins as opposed to being able to slowly cut mixture in some.
Starting techniques, leaning, gaining max performance etc... are all operational parameters that are particular to specific aircraft and the manufacturers recommendations should be followed.
The amount of different techniques i've seen to start engines when the POH works every time. If it doesn't something is wrong with it, get it fixed.
It's just as easy to slowly reduce and increase power using the mixture control, on systems like the one fitted to my aircraft.
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Just for the record I think there has been some misinformation put forward by some posters on this and other threads about asymmetric ops in light twins( <5700kgs).
Leadsled said
Rose Thorns said
For starters I can’t think of any ME instructors, ATO’s or FOI’s myself included who would advocate doing "V1 style cuts" in a light piston twin(<5700kg). I do agree that asymmetric training has a higher degree of risk not present in normal operations. Therefore most operators I know mitigate that risk by setting safe speed margins and imposing altitude restrictions for the conduct of simulated asymmetric training. Most of these limits will be covered in their respective ops manual.
The following is the technique by which an EFATO in a light twin is simulated by most of the operators I have had dealings with over the years including.
· Day VMC
· Not below Vtoss +10
· Undercarriage Up
· Take-Off Flap (Which in most light twins is Up anyway)
· Altitude not below 300 feet (some operators use 400ft)
· Mixture ICO until the failed engine is correctly identified then full rich
· Set zero thrust.
Using the B76 Duchess as an example Vmca =65kts, Vsse=71Kts, TOSS=80kts, Vyse=85kts & Vtoss +10=90kts. Passing 300ft I would cover the mixture control with a folded piece of paper & select one mixture to ICO announcing “simulated engine failure”
Bloggs goes through the EFATO touch drills & when he/she gets to the Identify “dead leg dead engine” confirm by closing the appropriate throttle “Feather....... (Left/Right)” this would be the instructors cue to return the mixture to full rich & set zero thrust. Most people can get through the drills comfortably in about 20 to 25 seconds therefore the mixture is in ICO for less than 30 sec before being set to full rich.
The advantages of using this technique are as follows:
· The student gets a more realistic indication of what an actual engine failure is like i.e. the yaw and drag from the windmilling prop and the change in performance when “zero thrust” is set.
· Most importantly they can’t second guess which engine has failed by looking at the closed throttle, they have to correctly identify (dead leg dead engine) & confirm by closing the correct throttle.
· If things go wrong then simply pushing the mixture up to full rich will restore power pretty quickly which I have done a number of occasions. The pitch locks don't engage till approx 800RPM on most twins & the engine RPM when windmilling is well above that.
· As for losing control remember we are at least 25kts above Vmca & 19kts above Vsse with U/C & flap up when the failure is introduced. The tolerance for an asymmetric departure on an IRT is plus 5kts minus 0kts of your nominated climb out speed which in this case is Vyse (85kts). So if blogs is having a bad day & lets the speed reduce to say 80kts you would still be 9kts above Vsse & 15 kts above Vmca.
· Failing an engine using the mixture is supposed to be kinder to the engine due to the fact that the throttle is wide open allowing the cylinders to fill up with air which cushions the deceleration of the engine.
· As for damaging turbos, cracking cylinders or crank cases then I don’t think it matters what method is used. If you slowly close the throttle or slowly close the mixture EGT/CHT & turbine speed will decrease rapidly so you can take your pick. The best way to prevent the above would be to not do asymmetric training & is probably why most asymmetric training is done on normally aspirated 4 cylinder engines like the venerable Lycoming IO-360or IO-320.
Centaurus
I do remember the accident you refer to quite well & I cannot see how failing the engine with the throttle as opposed the mixture could have resulted in a different outcome. If the exercise had occurred during daylight (which it should have been) then I am pretty sure the outcome would have been different as is evidenced from the following extract from the ATSB accident report analysis.
Leadsled said
But, as most of us know there is a dangerous percentage of pilots in both CASA and industry who are still gung ho ---- actually justifying that they are still alive as "testimony" to the fact that you are a wuzz if you don't do "V1 Cuts" on light twins that are not certified with a capability which includes such concepts as V1 and continue with the takeoff.
Rose Thorns said
But you start buggering about at zot feet with nothing on the clock but a makers name and, soon or late your luck will run out. That is not IF - only when. QED
The following is the technique by which an EFATO in a light twin is simulated by most of the operators I have had dealings with over the years including.
· Day VMC
· Not below Vtoss +10
· Undercarriage Up
· Take-Off Flap (Which in most light twins is Up anyway)
· Altitude not below 300 feet (some operators use 400ft)
· Mixture ICO until the failed engine is correctly identified then full rich
· Set zero thrust.
Using the B76 Duchess as an example Vmca =65kts, Vsse=71Kts, TOSS=80kts, Vyse=85kts & Vtoss +10=90kts. Passing 300ft I would cover the mixture control with a folded piece of paper & select one mixture to ICO announcing “simulated engine failure”
Bloggs goes through the EFATO touch drills & when he/she gets to the Identify “dead leg dead engine” confirm by closing the appropriate throttle “Feather....... (Left/Right)” this would be the instructors cue to return the mixture to full rich & set zero thrust. Most people can get through the drills comfortably in about 20 to 25 seconds therefore the mixture is in ICO for less than 30 sec before being set to full rich.
The advantages of using this technique are as follows:
· The student gets a more realistic indication of what an actual engine failure is like i.e. the yaw and drag from the windmilling prop and the change in performance when “zero thrust” is set.
· Most importantly they can’t second guess which engine has failed by looking at the closed throttle, they have to correctly identify (dead leg dead engine) & confirm by closing the correct throttle.
· If things go wrong then simply pushing the mixture up to full rich will restore power pretty quickly which I have done a number of occasions. The pitch locks don't engage till approx 800RPM on most twins & the engine RPM when windmilling is well above that.
· As for losing control remember we are at least 25kts above Vmca & 19kts above Vsse with U/C & flap up when the failure is introduced. The tolerance for an asymmetric departure on an IRT is plus 5kts minus 0kts of your nominated climb out speed which in this case is Vyse (85kts). So if blogs is having a bad day & lets the speed reduce to say 80kts you would still be 9kts above Vsse & 15 kts above Vmca.
· Failing an engine using the mixture is supposed to be kinder to the engine due to the fact that the throttle is wide open allowing the cylinders to fill up with air which cushions the deceleration of the engine.
· As for damaging turbos, cracking cylinders or crank cases then I don’t think it matters what method is used. If you slowly close the throttle or slowly close the mixture EGT/CHT & turbine speed will decrease rapidly so you can take your pick. The best way to prevent the above would be to not do asymmetric training & is probably why most asymmetric training is done on normally aspirated 4 cylinder engines like the venerable Lycoming IO-360or IO-320.
Centaurus
I do remember the accident you refer to quite well & I cannot see how failing the engine with the throttle as opposed the mixture could have resulted in a different outcome. If the exercise had occurred during daylight (which it should have been) then I am pretty sure the outcome would have been different as is evidenced from the following extract from the ATSB accident report analysis.
The simulated engine failure just after takeoff did not provide those adequate margins, especially at night, with inadequate visual reference to ensure obstacle clearance. It was likely that the ATO may not have been aware that the aircraft was not climbing and had drifted well right of the runway toward obstacles and higher ground. Although he reapplied full power to the simulated 'failed' engine at either the candidate's expressed concern or out of his own concern, the response was not timely enough to avoid a collision with the tree or the ground.” (my bolding)
· Mixture ICO until the failed engine is correctly identified then full rich
· The student gets a more realistic indication of what an actual engine failure is like i.e. the yaw and drag from the windmilling prop and the change in performance when “zero thrust” is set.
Do you also load the aircraft to maximum weight with the most rearward possible CoG? As the aircraft will behave differently again as load distribution and weight change.
Its more about the drill than scaring someone with low level lack of performance.
I would demonstrate the "real thing" at safe altitude and involve a full feather and shut down. This does not need to be replicated to ground level or even in the circuit.
· Most importantly they can’t second guess which engine has failed by looking at the closed throttle, they have to correctly identify (dead leg dead engine) & confirm by closing the correct throttle.
· As for losing control remember we are at least 25kts above Vmca & 19kts above Vsse with U/C & flap up when the failure is introduced. The tolerance for an asymmetric departure on an IRT is plus 5kts minus 0kts of your nominated climb out speed which in this case is Vyse (85kts). So if blogs is having a bad day & lets the speed reduce to say 80kts you would still be 9kts above Vsse & 15 kts above Vmca.
· As for damaging turbos, cracking cylinders or crank cases then I don’t think it matters what method is used. If you slowly close the throttle or slowly close the mixture EGT/CHT & turbine speed will decrease rapidly so you can take your pick. The best way to prevent the above would be to not do asymmetric training & is probably why most asymmetric training is done on normally aspirated 4 cylinder engines like the venerable Lycoming IO-360or IO-320.
Centaurus
Centaurus
Last edited by 43Inches; 3rd Aug 2010 at 09:40.
my inexpert response is either that you are reducing the mixture veeeeerrrrry slowly or, if not, don't do it on that kind of engine.
Not debating here whether damage will occur in the long term. More what is appropriate for a training exercise in general. What will preserve your skin over time and your bank balance if you ever have to attend court over an accident.
I used to practice mixture cuts, turning off the fuel, you name it did it then woke up to whether it was really worth it in the big scheme of things, did it improve the students, no.
Any variation from the manufacturers advice followed by an accident will be hard to fight against a well prepared oponant in law.
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Hi 43inches
I hear you but?
So does that mean you use the manufactures checklist for each & every flight verbatum for the PA44? & the manufactures Wt&Bal & unfactored Performance data data for each flight? Seriously?
Yes I did as it happens max fuel & bundles of old news paper but it was really only as good as the first take-off.
Yes I agree with the first part however it's pretty hard to scare someone when the mixture is at ICO for less than thirty seconds while they carry out the drills then zero thrust is set.
Yes I did the same at altitude until I was satisfied that the trainee had it together & knew left from right. I did however replicate it at 300 or 400 feet above ground level, as did you by closing the throttle & then setting zero thrust, however I did by selecting ICO then zero thrust.
Yes I agree however I didn't have the benefit of synthetic trainers back then, I do have the benefit of full motion sims nowadays which makes life somwhat easier, & turbine aircraft which actually perform.
Yep me too however I just said taking over & with palm outstretched pushed it all forward & had another go.
I have instructed on the older style Baron's & the throttle in the middle concept is hard to get used to, the ones I used to instruct on were all black knobs as well
, all I can say is I hope the hapless student didn't get confused about the gear & flap lever as well.
Hmmm how slowly are we talking about here I am talking maybe 3 or 4 secs. How slowly do you close the throttle?
I hear you but?
Used to do this until I realised the POH (PA44) advised against it, purely because if something does go wrong you are in serious trouble legally.
Do you also load the aircraft to maximum weight with the most rearward possible CoG? As the aircraft will behave differently again as load distribution and weight change.
Its more about the drill than scaring someone with low level lack of performance
I would demonstrate the "real thing" at safe altitude and involve a full feather and shut down. This does not need to be replicated to ground level or even in the circuit.
Again this would be found out by rigourous practice at altitude or even better in the sim. If the student has this problem spend an hour in a twin engine synthetic trainer, this way you can repeat the scenario numerous times with no risk. Its cheap for the candidate, gets the desired learning outcome then return to the real aircraft.
I have had a few students attempt to kick full rudder towards the failed engine in the circuit. In all circumstances I had reduced the throttle and as my hand was right there power was reapplied, control removed from the student and a speedy recovery to normal flight resumed. Had I pulled the mixture I would have to richen the mixture then move the throttles forward. You would be surprised at what students can do in the heat of the moment, close both throttles, try to feather without any drill etc...
I know of one situation in a Baron where the student closed the other mixture (instead of the throttle) during late downwind/base so that the aircraft now had both engines shut down.
, all I can say is I hope the hapless student didn't get confused about the gear & flap lever as well.
It is not the rapid loss of temperature that is the problem with a turbo-charged engine, however on a warm day if you slowly move the mixture to ICO then you will pass through peak EGT which at full power may exceed the maximum permissible. Moved quickly no problem as the temperature has no time to build up.
Last edited by betaman; 3rd Aug 2010 at 11:46.
So does that mean you use the manufactures checklist for each & every flight verbatum for the PA44? & the manufactures Wt&Bal & unfactored Performance data data for each flight? Seriously?
The checklists complied with the manufacturer and with additional items for local variations.