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lencarne

One engine take off

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I am keen to do some check ride things like V1 or V2 cut . However I always end up crashing. Guess thats why its a checkride item huh? lol  Anyway some hints and tips would be much appreciated, I dare not even suggest that its not simulated in the PMDG 737NGX!!

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I'm sorry... Have you asked any particular question?

I apologize if I have misunderstood something

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Not a 737 expert, but some general pieces of advice:

 

Firstly, what hardware do you have? Silly question, perhaps, but it should be noted that asymmetric flight absolutely requires rudder pedals (or at the very least some form of separate yaw control, even if it's a twist action joystick). Autorudder won't cut it here.

 

When practicing, try using wet V speeds to start off with as this will give a greater spread between V1 and VR and thus give you a little more time to control the aircraft. Make sure that your speeds are correct for the weight and thrust setting - remember that de-rated (distinct from assumed temperature) thrust will affect VMC and if you try to use V-speeds calculated for de-rated thrust with full thrust (or advance the thrust levers beyond the de-rated thrust setting) you may find yourself asymmetric below VMC and in this situation you will run out of options very quickly (indeed, the only way to regain control in that situation is to reduce thrust on the operating engine).

 

So, with that out of the way:

 

In an engine failure situation the first and most important action is to stop the yaw. Stopping the yaw is the only way to regain control. To stop the yaw, smoothly apply rudder pressure in the opposite direction to the yaw in order to keep the aeroplane straight, using up to full rudder if necessary. If the yaw cannot be stopped even with full rudder application, the only way to control the aeroplane is to reduce the yawing moment due to thrust by reducing thrust on the live engine, even if you have to accept a severe performance reduction as a result. Either way, the yaw must be stopped. Fortunately (theoretically, given the limitations of the sim -- as I say, I don't know how close the NGX gets to the numbers) in a Performance Class A jet like the NG your takeoff performance numbers should provide adequate margins above VMCA/VMCG to allow you to leave the thrust where it is.

 

It is important the the rudder is used first to stop the yaw. Obviously a yaw also results in a roll (remember those Effects of Controls!) and in an aircraft with a strong roll-yaw coupling it may be the case that the pilot perceives the roll first before the yaw. You must use the rudder to stop the yaw first. There have been many accidents and fatalities as a result of pilots trying to stop the roll with aileron before applying rudder.

 

This is a bad idea, because deflecting the ailerons increases drag and changes the angle of attack of the wing, potentially resulting in adverse aileron yaw (the reason why in a light aircraft we would apply rudder pressure when rolling in to a turn to balance). Deflecting the ailerons increases drag and increases the yaw, possibly to the point where it is no longer possible to stop the yaw with the rudder!

 

Once we have got the aeroplane under control by stopping the yaw, we are now looking for control combined with the least loss of performance. There are, broadly, three ways in which we could achieve control:

 

  • Bank towards the live engine with no rudder
  • Use rudder to stop the yaw and keep the wings level
  • Use rudder to stop the yaw and bank slightly in to the live engine

 

I won't go in to all of these in depth, but briefly we can throw out 1) immediately for the reasons above -- this would result in an enormous sideslip with an associated tremendous increase in drag, exactly what we don't want in a performance-critical situation like an EFATO.

 

2) is an acceptable compromise and makes asymmetric instrument flying easier, so this is a good method to use on approach etc. But there is still a residual sideslip in this situation, so some performance will be lost.

 

3) results in zero sideslip, and therefore the least performance penalty. This, therefore, is what we're looking for in a situtation where we need every ounce of performance (e.g. an EFATO/asymmetric GA etc).

 

So -- once the yaw has been stopped with rudder, you can apply a small amount of bank (no more than 3-5 degrees) in to the live engine. In this situation, the balance ball will be displaced slightly towards the live engine (typically by about half its width or thereabouts) -- this is due to gravity, not a sideslip. It does mean that it can become a slightly vague reference in IMC, so if in doubt level the wings with aileron and centre the ball with rudder until you have re-oriented yourself, when you can re-apply the bank towards the live engine to restore the best climb performance.

 

What you must do is get the gear up promptly once you have a positive rate of climb -- then sit on your hands and concentrate on flying the aeroplane up to a safe altitude. You can use the rudder trim to relieve the rudder pressure if you wish.

 

Once you are at a safe height (typically a minimum of 400ft AGL but as you are likely single-pilot you may wish to wait a bit longer) you can then start to deal with securing the engine -- the specifics will be in the QRH but broadly the sequence will be to identify the failed engine (dead leg (i.e. the leg not applying any rudder pressure) = dead engine -- it is perhaps even a good idea to slap your 'dead' leg as a confirmation before touching anything. This is the most reliable way to ID the dead engine -- remember the gauges may or may not give obvious indications, and the last thing you want to do is to shut down the good engine). Once you have identified which engine is failed, you then positively identify the appropriate thrust lever (in a multi-crew cockpit you would both confirm that you have the right one) and slowly retard it to idle (checking, obviously, that you don't find yourself suddenly out of climb performance -- i.e. wrong engine).

 

Once you have done this you would usually then carry out the rest of the drills (some airlines might ask you do to a full 'fire' shutdown in all cases, others might only ask you to do so in the event of 'severe damage') -- essentially positively identify and select the appropriate fire handle/fuel control switch to OFF etc.

 

As far as actually flying is concerned, remember that any changes in thrust will require an alteration in rudder pressure/rudder trim (which can be a little fiddly in FS with no force feedback) - manual thrust would be a good idea (if not mandated by the FCOM). The climb-out attitude will be a little lower than normal, and expect a significant reduction in climb performance. Maintain take-off thrust up to acceleration altitude, at which point you can then level off (or more or less) with TO thrust set, accelerate, clean up the flaps, then select MCT on the live engine and FLCH up further as required.

 

Is that helpful?

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Not a 737 expert, but some general pieces of advice:

 

Firstly, what hardware do you have? Silly question, perhaps, but it should be noted that asymmetric flight absolutely requires rudder pedals (or at the very least some form of separate yaw control, even if it's a twist action joystick). Autorudder won't cut it here.

 

When practicing, try using wet V speeds to start off with as this will give a greater spread between V1 and VR and thus give you a little more time to control the aircraft. Make sure that your speeds are correct for the weight and thrust setting - remember that de-rated (distinct from assumed temperature) thrust will affect VMC and if you try to use V-speeds calculated for de-rated thrust with full thrust (or advance the thrust levers beyond the de-rated thrust setting) you may find yourself asymmetric below VMC and in this situation you will run out of options very quickly (indeed, the only way to regain control in that situation is to reduce thrust on the operating engine).

 

So, with that out of the way:

 

In an engine failure situation the first and most important action is to stop the yaw. Stopping the yaw is the only way to regain control. To stop the yaw, smoothly apply rudder pressure in the opposite direction to the yaw in order to keep the aeroplane straight, using up to full rudder if necessary. If the yaw cannot be stopped even with full rudder application, the only way to control the aeroplane is to reduce the yawing moment due to thrust by reducing thrust on the live engine, even if you have to accept a severe performance reduction as a result. Either way, the yaw must be stopped. Fortunately (theoretically, given the limitations of the sim -- as I say, I don't know how close the NGX gets to the numbers) in a Performance Class A jet like the NG your takeoff performance numbers should provide adequate margins above VMCA/VMCG to allow you to leave the thrust where it is.

 

It is important the the rudder is used first to stop the yaw. Obviously a yaw also results in a roll (remember those Effects of Controls!) and in an aircraft with a strong roll-yaw coupling it may be the case that the pilot perceives the roll first before the yaw. You must use the rudder to stop the yaw first. There have been many accidents and fatalities as a result of pilots trying to stop the roll with aileron before applying rudder.

 

This is a bad idea, because deflecting the ailerons increases drag and changes the angle of attack of the wing, potentially resulting in adverse aileron yaw (the reason why in a light aircraft we would apply rudder pressure when rolling in to a turn to balance). Deflecting the ailerons increases drag and increases the yaw, possibly to the point where it is no longer possible to stop the yaw with the rudder!

 

Once we have got the aeroplane under control by stopping the yaw, we are now looking for control combined with the least loss of performance. There are, broadly, three ways in which we could achieve control:

 

  • Bank towards the live engine with no rudder
  • Use rudder to stop the yaw and keep the wings level
  • Use rudder to stop the yaw and bank slightly in to the live engine

 

I won't go in to all of these in depth, but briefly we can throw out 1) immediately for the reasons above -- this would result in an enormous sideslip with an associated tremendous increase in drag, exactly what we don't want in a performance-critical situation like an EFATO.

 

2) is an acceptable compromise and makes asymmetric instrument flying easier, so this is a good method to use on approach etc. But there is still a residual sideslip in this situation, so some performance will be lost.

 

3) results in zero sideslip, and therefore the least performance penalty. This, therefore, is what we're looking for in a situtation where we need every ounce of performance (e.g. an EFATO/asymmetric GA etc).

 

So -- once the yaw has been stopped with rudder, you can apply a small amount of bank (no more than 3-5 degrees) in to the live engine. In this situation, the balance ball will be displaced slightly towards the live engine (typically by about half its width or thereabouts) -- this is due to gravity, not a sideslip. It does mean that it can become a slightly vague reference in IMC, so if in doubt level the wings with aileron and centre the ball with rudder until you have re-oriented yourself, when you can re-apply the bank towards the live engine to restore the best climb performance.

 

What you must do is get the gear up promptly once you have a positive rate of climb -- then sit on your hands and concentrate on flying the aeroplane up to a safe altitude. You can use the rudder trim to relieve the rudder pressure if you wish.

 

Once you are at a safe height (typically a minimum of 400ft AGL but as you are likely single-pilot you may wish to wait a bit longer) you can then start to deal with securing the engine -- the specifics will be in the QRH but broadly the sequence will be to identify the failed engine (dead leg (i.e. the leg not applying any rudder pressure) = dead engine -- it is perhaps even a good idea to slap your 'dead' leg as a confirmation before touching anything. This is the most reliable way to ID the dead engine -- remember the gauges may or may not give obvious indications, and the last thing you want to do is to shut down the good engine). Once you have identified which engine is failed, you then positively identify the appropriate thrust lever (in a multi-crew cockpit you would both confirm that you have the right one) and slowly retard it to idle (checking, obviously, that you don't find yourself suddenly out of climb performance -- i.e. wrong engine).

 

Once you have done this you would usually then carry out the rest of the drills (some airlines might ask you do to a full 'fire' shutdown in all cases, others might only ask you to do so in the event of 'severe damage') -- essentially positively identify and select the appropriate fire handle/fuel control switch to OFF etc.

 

As far as actually flying is concerned, remember that any changes in thrust will require an alteration in rudder pressure/rudder trim (which can be a little fiddly in FS with no force feedback) - manual thrust would be a good idea (if not mandated by the FCOM). The climb-out attitude will be a little lower than normal, and expect a significant reduction in climb performance. Maintain take-off thrust up to acceleration altitude, at which point you can then level off (or more or less) with TO thrust set, accelerate, clean up the flaps, then select MCT on the live engine and FLCH up further as required.

 

Is that helpful?

 

Quite the write-up. A lot of good info. Some of that guidance (3-5 degree bank into the goo) is more for a light twin than a swept-wing jet, isn't it?

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Quite the write-up. A lot of good info. Some of that guidance (3-5 degree bank into the goo) is more for a light twin than a swept-wing jet, isn't it?

 

Thank you! I'm in the middle of helping to write up an FS ME course at the moment, so I've been practicing this sort of stuff a fair bit and had my head in a lot of textbooks, so it's all quite fresh in the mind -- the one thing that really struck me (probably more applicable to a light prop twin rather than a jet) was the difficulty in IDing the failed engine from the gauges with a windmilling prop (anyone who's never tried it -- there's surprisingly little change), so the dead leg/dead engine thing in particular stuck quite well (I also recall being at a talk by Capt Eric Moody, the BA9 skipper who experienced quadruple engine failure in a B742 over Indonesia, who mentioned that when he'd had engine failures in the sim the gauges all neatly span down to 0 etc, but on that night when he looked the gauges were nonsensical -- just all over the place).

 

Re: swept wing jets -- that's a  good point and I'd love to hear more on the NG/swept wing jet specifics. I do seem to recall that it is fairly typical to end up with a small amount of bank in to the good engine even on a jet, though isn't it? (Though applying sufficient rudder (trim) to leave the control column level (i.e. neutral ailerons) also seems to ring a bell).

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Boeing states to keep the control wheel neutral,as an extended spoiler will severely affect single engine climb performance.

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Re: swept wing jets -- that's a  good point and I'd love to hear more on the NG/swept wing jet specifics. I do seem to recall that it is fairly typical to end up with a small amount of bank in to the good engine even on a jet, though isn't it? (Though applying sufficient rudder (trim) to leave the control column level (i.e. neutral ailerons) also seems to ring a bell).

 

 

IIRC, In the US, there is a difference on how the light aircraft are certified under Part 23 and commercial aircraft are under Part 25. So, a light twin, like a Seminole or Dutchess, etc, you'd need to have the bank into the good engine as per your post. Like Jim said, for Boeing's, it's level the yoke.

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That slight bank into the good engine evaporates with something even a little heavier than a Seminole.  The "light" C-414 Chancellor is flown wings level, as I've had to do on two occasions. Luckily, only one was an engine loss... the other being a precautionary shut down. It was very easy to fly single engine up until the landing then it gets interesting.

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Boeing states to keep the control wheel neutral,as an extended spoiler will severely affect single engine climb performance.

 

Makes sense -- drag from slight residual sideslip < drag from roll spoiler extension.

 

 

 


In the US, there is a difference on how the light aircraft are certified under Part 23 and commercial aircraft are under Part 25.

 

Indeed -- amongst other things, older light twins have no requirement to be able to achieve a positive rate of climb OEI, at any altitude (even sea level). I think that has since been changed, but it's still all very marginal.

 

Cheers!

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Points i always consider;

 

The following sequence of events should be followed:

• Fly at the UP speed until above MSA

• Complete the appropriate QRH Non Normal checklist

• Complete the AFTER T/O checklist

• Decide on a best course of action using the P-I-O-S-E-E* model, do a NITS briefing and make a PA. (PIOSEE-NITS-PA).

*Problem-Information-Options-Select-Execute-Evaluate.

 

And remember- aviate navigate communicate

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Not a 737 expert, but some general pieces of advice:

 

Firstly, what hardware do you have? Silly question, perhaps, but it should be noted that asymmetric flight absolutely requires rudder pedals (or at the very least some form of separate yaw control, even if it's a twist action joystick). Autorudder won't cut it here.

 

When practicing, try using wet V speeds to start off with as this will give a greater spread between V1 and VR and thus give you a little more time to control the aircraft. Make sure that your speeds are correct for the weight and thrust setting - remember that de-rated (distinct from assumed temperature) thrust will affect VMC and if you try to use V-speeds calculated for de-rated thrust with full thrust (or advance the thrust levers beyond the de-rated thrust setting) you may find yourself asymmetric below VMC and in this situation you will run out of options very quickly (indeed, the only way to regain control in that situation is to reduce thrust on the operating engine).

 

So, with that out of the way:

 

In an engine failure situation the first and most important action is to stop the yaw. Stopping the yaw is the only way to regain control. To stop the yaw, smoothly apply rudder pressure in the opposite direction to the yaw in order to keep the aeroplane straight, using up to full rudder if necessary. If the yaw cannot be stopped even with full rudder application, the only way to control the aeroplane is to reduce the yawing moment due to thrust by reducing thrust on the live engine, even if you have to accept a severe performance reduction as a result. Either way, the yaw must be stopped. Fortunately (theoretically, given the limitations of the sim -- as I say, I don't know how close the NGX gets to the numbers) in a Performance Class A jet like the NG your takeoff performance numbers should provide adequate margins above VMCA/VMCG to allow you to leave the thrust where it is.

 

It is important the the rudder is used first to stop the yaw. Obviously a yaw also results in a roll (remember those Effects of Controls!) and in an aircraft with a strong roll-yaw coupling it may be the case that the pilot perceives the roll first before the yaw. You must use the rudder to stop the yaw first. There have been many accidents and fatalities as a result of pilots trying to stop the roll with aileron before applying rudder.

 

This is a bad idea, because deflecting the ailerons increases drag and changes the angle of attack of the wing, potentially resulting in adverse aileron yaw (the reason why in a light aircraft we would apply rudder pressure when rolling in to a turn to balance). Deflecting the ailerons increases drag and increases the yaw, possibly to the point where it is no longer possible to stop the yaw with the rudder!

 

Once we have got the aeroplane under control by stopping the yaw, we are now looking for control combined with the least loss of performance. There are, broadly, three ways in which we could achieve control:

 

  • Bank towards the live engine with no rudder
  • Use rudder to stop the yaw and keep the wings level
  • Use rudder to stop the yaw and bank slightly in to the live engine

 

I won't go in to all of these in depth, but briefly we can throw out 1) immediately for the reasons above -- this would result in an enormous sideslip with an associated tremendous increase in drag, exactly what we don't want in a performance-critical situation like an EFATO.

 

2) is an acceptable compromise and makes asymmetric instrument flying easier, so this is a good method to use on approach etc. But there is still a residual sideslip in this situation, so some performance will be lost.

 

3) results in zero sideslip, and therefore the least performance penalty. This, therefore, is what we're looking for in a situtation where we need every ounce of performance (e.g. an EFATO/asymmetric GA etc).

 

So -- once the yaw has been stopped with rudder, you can apply a small amount of bank (no more than 3-5 degrees) in to the live engine. In this situation, the balance ball will be displaced slightly towards the live engine (typically by about half its width or thereabouts) -- this is due to gravity, not a sideslip. It does mean that it can become a slightly vague reference in IMC, so if in doubt level the wings with aileron and centre the ball with rudder until you have re-oriented yourself, when you can re-apply the bank towards the live engine to restore the best climb performance.

 

What you must do is get the gear up promptly once you have a positive rate of climb -- then sit on your hands and concentrate on flying the aeroplane up to a safe altitude. You can use the rudder trim to relieve the rudder pressure if you wish.

 

Once you are at a safe height (typically a minimum of 400ft AGL but as you are likely single-pilot you may wish to wait a bit longer) you can then start to deal with securing the engine -- the specifics will be in the QRH but broadly the sequence will be to identify the failed engine (dead leg (i.e. the leg not applying any rudder pressure) = dead engine -- it is perhaps even a good idea to slap your 'dead' leg as a confirmation before touching anything. This is the most reliable way to ID the dead engine -- remember the gauges may or may not give obvious indications, and the last thing you want to do is to shut down the good engine). Once you have identified which engine is failed, you then positively identify the appropriate thrust lever (in a multi-crew cockpit you would both confirm that you have the right one) and slowly retard it to idle (checking, obviously, that you don't find yourself suddenly out of climb performance -- i.e. wrong engine).

 

Once you have done this you would usually then carry out the rest of the drills (some airlines might ask you do to a full 'fire' shutdown in all cases, others might only ask you to do so in the event of 'severe damage') -- essentially positively identify and select the appropriate fire handle/fuel control switch to OFF etc.

 

As far as actually flying is concerned, remember that any changes in thrust will require an alteration in rudder pressure/rudder trim (which can be a little fiddly in FS with no force feedback) - manual thrust would be a good idea (if not mandated by the FCOM). The climb-out attitude will be a little lower than normal, and expect a significant reduction in climb performance. Maintain take-off thrust up to acceleration altitude, at which point you can then level off (or more or less) with TO thrust set, accelerate, clean up the flaps, then select MCT on the live engine and FLCH up further as required.

 

Is that helpful?

Wow Simon! thanx for your PhD thesis in answer to my question. Will try again using rudder until wing level - I was hard over on both rudder and aerelon and crashed - no time for niceities like QRH etc LOL. Thnx once again. I fly a livery G-DOCX as a NGX 800  - it was the last BA Boeing 737... maybe i will join BA virtual some day but i guess it has to be an airbus huh? Dont wanna do 747 yet.

I'm sorry... Have you asked any particular question?

I apologize if I have misunderstood something

Anyway some hints and tips would be much appreciated,

Thank you! I'm in the middle of helping to write up an FS ME course at the moment, so I've been practicing this sort of stuff a fair bit and had my head in a lot of textbooks, so it's all quite fresh in the mind -- the one thing that really struck me (probably more applicable to a light prop twin rather than a jet) was the difficulty in IDing the failed engine from the gauges with a windmilling prop (anyone who's never tried it -- there's surprisingly little change), so the dead leg/dead engine thing in particular stuck quite well (I also recall being at a talk by Capt Eric Moody, the BA9 skipper who experienced quadruple engine failure in a B742 over Indonesia, who mentioned that when he'd had engine failures in the sim the gauges all neatly span down to 0 etc, but on that night when he looked the gauges were nonsensical -- just all over the place).

 

Re: swept wing jets -- that's a  good point and I'd love to hear more on the NG/swept wing jet specifics. I do seem to recall that it is fairly typical to end up with a small amount of bank in to the good engine even on a jet, though isn't it? (Though applying sufficient rudder (trim) to leave the control column level (i.e. neutral ailerons) also seems to ring a bell).

His engine failures were due to volcanic ash as I remember so his pito tubes etc were affected too. What a guy tho...  landing visual thro the side window. Balls or what!!

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Wow Simon! thanx for your PhD thesis in answer to my question. Will try again using rudder until wing level - I was hard over on both rudder and aerelon and crashed - no time for niceities like QRH etc LOL. Thnx once again. I fly a livery G-DOCX as a NGX 800  - it was the last BA Boeing 737... maybe i will join BA virtual some day but i guess it has to be an airbus huh? Dont wanna do 747 yet.

 

You're welcome! You will likely need a little aileron to level the wings as you get airborne, but ultimately keep straight with the rudder and keep the slip indicator at the top of the PFD close to centred. Once you have got the gear up and are safely climbing away you can then add a little more rudder pressure (in the same direction as the yoke is displaced) to level the control wheel (which may result in a small residual bank towards the live engine, but in any event will result in constant heading).

 

"Squeeze, freeze, twelve degrees" is a nice mnemonic I saw earlier whilst looking in to this a bit more deeply -- squeeze the rudder as required to maintain centreline - freeze the rudder input once you have the appropriate amount to keep straight (lock your leg in that position) - then rotate to the EO pitch attitude of twelve degrees nose up.

 

We'd be delighted to have you along at BAV - it does have to be the Airbus for short-haul these days, though if you're in to the classics we have an extensive set of schedules from the BEA/BOAC days as well, a VFR flying club and once you've logged a few hours of course you get access to the long-haul schedules - 767/747/777/787/A380 etc. Shout if you have any questions!

 

 

 


His engine failures were due to volcanic ash as I remember so his pito tubes etc were affected too. What a guy tho...  landing visual thro the side window. Balls or what!!

 

Indeed! His story about how he became a pilot was quite interesting as well -- amongst other things, when he first applied to Hamble he was rejected on medical grounds because, supposedly, his nose was slightly crooked. To cut a long story short, he ended up going to a surgeon to get it fixed, was eventually accepted and the rest is history...

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Simon, wonderful explanations there.  BA Virtual is lucky to have you.

 

Hope you can share some of your writings when you are finished :)

 

Great job, mate.

 

Cheers,

Rudy

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I didnt read EVERYTHING but on a transport category airplane, NEVER EVER EVER EVER REDUCE THRUST ON THE OPERATING ENGINE!!!! On a V1 cut, you already have enough speed to get into the air because by the time you recognize the failure and start correcting the yaw, youll be at rotation speed. When you get the airplane controlled, even if you run out of rudder, get the airplane in the air.

 

Once thats accomplished, get it coordinated and the airplane will fly nicely.

 

Thurst aettings dont matter. When you get your takeoff thrust settings, de rated or full, thays what youll be using fkr the takeoff. VMC doesnt matter because v2 will protect you in that regard.

 

Anyways, on most if not all transport category airplanes, youll go to max continuoise thrust once youre in the air at a certain point depending on your V1 cut profile.

 

Its all about the profile you fly.

 

Long story short, any multi engine stuff you learn from a seminole will not carry over to a 737. Onky basic basic stuff. No procedural stuff.

 

Just yo be clear, aerodynamically, its vlose but not the same. This is in regards to slipping and turning into or away from a dead engine and the effects it has on drag and flight path. However, how you fly the airplane is completely different.

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Thurst aettings dont matter. When you get your takeoff thrust settings, de rated or full, thays what youll be using fkr the takeoff. VMC doesnt matter because v2 will protect you in that regard.

 

But it does matter if you are using de-rated thrust (TO1/TO2), because VMC (and therefore V2) is predicated on the de-rated thrust setting.

 

If you use speeds calculated for TO2 with full thrust, you may get in to bother, especially at the lower end of the speed schedule, and you cannot just firewall the thrust on the operating engine if you conducting a de-rated takeoff for the same reason (and even at higher weights the rate of change of thrust may be problematic given that the book VMCA is flight-tested under relatively benign conditions).

 

An assumed temperature reduction is of course a different matter and can be safely removed with a single click of the TOGA switches if desired. But if you are using TO1/TO2 -- the second click that gives you max thrust may not be a good idea.

 

I absolutely agree that there should never be a situation where you should be in VMC trouble in a Perf A jet if you have done the sums correctly, and really the safest course of action is to leave the thrust exactly where it is -- as you say, any de-rate/ATM reduction will have been calculated to provide a safe flight path.

 

There are, of course, handling differences between a light twin and a transport jet, but the basics -- stop the yaw, control the aeroplane and minimise the drag (which as pointed out above is of course affected by the roll spoilers, such that it is preferable to accept some sideslip in order to keep the ailerons/roll spoilers neutral) -- still apply.

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But it does matter if you are using de-rated thrust (TO1/TO2), because VMC (and therefore V2) is predicated on the de-rated thrust setting.

 

If you use speeds calculated for TO2 with full thrust, you may get in to bother, especially at the lower end of the speed schedule, and you cannot just firewall the thrust on the operating engine if you conducting a de-rated takeoff for the same reason (and even at higher weights the rate of change of thrust may be problematic given that the book VMCA is flight-tested under relatively benign conditions).

 

An assumed temperature reduction is of course a different matter and can be safely removed with a single click of the TOGA switches if desired. But if you are using TO1/TO2 -- the second click that gives you max thrust may not be a good idea.

 

I absolutely agree that there should never be a situation where you should be in VMC trouble in a Perf A jet if you have done the sums correctly, and really the safest course of action is to leave the thrust exactly where it is -- as you say, any de-rate/ATM reduction will have been calculated to provide a safe flight path.

 

There are, of course, handling differences between a light twin and a transport jet, but the basics -- stop the yaw, control the aeroplane and minimise the drag (which as pointed out above is of course affected by the roll spoilers, such that it is preferable to accept some sideslip in order to keep the ailerons/roll spoilers neutral) -- still apply.

we are speaking the same language lol. I just had to point out that reduction of thrust will never happen. At V1 youre committed (i know you know that, youre a smart and well educated person).

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I am keen to do some check ride things like V1 or V2 cut . However I always end up crashing. Guess thats why its a checkride item huh? lol  Anyway some hints and tips would be much appreciated, I dare not even suggest that its not simulated in the PMDG 737NGX!!

Hi Len, looks like you've got all the guidance from Skelsey here and all the background information. Some beef to back you up and how to physically fly a 737 NG during an EFATO! A few more tips for you, it’s what we teach cadets and reinforce during recurrent training and the differences between a light MEP and a Multi-Engine Jet.

 

Firstly and what might seem a bit obvious, reject the take off before V1. This is because V1 must not be lower than VMCG, VMCG (Velocity of Minimum Control on Ground) is the slowest speed with which there is sufficient rudder authority to continue a take-off in the event of an engine failure.

 

If the engine fails after V1 smoothly apply rudder to maintain runway centreline. There’s a big difference in how quickly you apply rudder depending on say an engine flameout and severe damage.

 

At VR (Rotation Speed) start a smooth continuous rotation to a target pitch attitude of 12.5 degrees at approximately 1.5/2 degrees per second (normal two engine rotation 2/2.5 degrees per second approximately 15 degrees).

 

Throughout the rotation maintain direction control with the use of rudder AND aileron. You shouldn’t need too much aileron if you have the correct amount of rudder input. After a positive rate of climb raise the landing gear.

 

Now the best tool you have is the flight director. The flight director after an engine failure will command a pitch to fly to maintain a speed between V2 and V2 + 20 depending at what speed the engine failure occurred. V2 is the minimum speed to fly to maintain the minimum required climb gradient and to maintain aircraft control.

 

At 400ft AGL we would select HDG SEL and initiate any memory items specific to the failure, for example an engine fire needs to be dealt with promptly but an engine flameout we can deal with later.

 

It’s worth quickly noting we would generally maintain RWY Heading after an engine failure at V1 and climb to the MSA. If terrain is an issue at the particular airport our company has specified Emergency Turn Procedures to comply with to keep us away from terrain.

 

This pitch attitude is maintained until reaching MFRA (Minimum Flap Retraction Altitude) and is typically 1000ft above aerodrome elevation. At MFRA, which we would have set on the EFIS MINS BARO, we BUG UP and retract the flap. This is the engine-out acceleration height and the flight director will now command an almost near level or slight climb. Whilst accelerating retract the flaps like you would after any departure.

 

Once the flaps are up we would then select LVL CHG and select Max Continuous Thrust in the FMC (NI Page and LSK CON) and then manually set thrust on the reaming engine to the N1 bug. You would then fly the UP speed until above the MSA.

 

Once above the MSA we would action the applicable QRH Non Normal Checklist, After Take Off checklist and decide on the best course of action!

 

Oh and a quick note regarding Engine Failure during Reduced Thrust (ATM) and/or Fixed Derate Thrust.

 

Skelsey is absolutely right, if you increase thrust after reducing the thrust before departure by fixed derate (for eg 22k or 24k) you could potentially lose directional control. This is because takeoff speeds consider VMCG and VMCA at the fixed derate level of thrust HOWEVER at the Captains discretion maximum thrust is available if in the opinion you might smash into the side of a mountain.

 

If thrust has been reduced by ATM you may increase thrust on the operating engine by setting N1 to the N1 reference bugs whilst maintaining direction control, this would provide an additional performance margin HOWEVER this shouldn’t be required as the take-off data is based on the ATM thrust setting. Unless you are massively mishandling the aircraft on one engine the extra thrust should not be required.

 

If you’re using a combination of both fixed derate and ATM the same applies if you were using just a fixed derate (don’t increase thrust unless there is a massive mountain in the way!)

 

That’s it in a very brief nutshell. As I always stress this is guidance based on Boeings FCTM and my operator and I hope you might find this information useful.

 

Oh and remember to turn off Autorudder in FSX settings! It might help!

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Well, thank  you all... I can now get the bird off the ground on one engine. Thanks to Sam, how nice to have someone explain an acronym in the first instance of use. I did see a glossary once...

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