RTO
Guest
Posts: n/a
Following Checkboard's post above in which he states that there is a margin built in to V1 for decision-making, I've now been able to check the following, by way of crossing 't's and dotting 'i's:
'The decision speed (V1) is the highest speed BY WHICH THE PILOT SHOULD HAVE MADE THE MENTAL DECISION TO REJECT THE TAKE-OFF...' (My capitals).
Reaction delays after V1 of up to two seconds are to allow for the execution of the appropriate actions to intitiate the reject.
'V1 must be respected as the latest speed by which a decision to stop must have been taken to assure a stopping capability within the distance available on a limiting runway'.
Thus, there is no 'thinking time' available after V1. My point about an FO calling a problem, say, five knots prior to V1, and thus setting in place a reject which occurs at a speed greater than V1, stands firm. Sorry, Checkboard, you need a re-think.
Source: AIC 141/1998 (Pink 182).
[This message has been edited by Captain Tobias Wilcox (edited 29 October 2000).]
[This message has been edited by Captain Tobias Wilcox (edited 29 October 2000).]
'The decision speed (V1) is the highest speed BY WHICH THE PILOT SHOULD HAVE MADE THE MENTAL DECISION TO REJECT THE TAKE-OFF...' (My capitals).
Reaction delays after V1 of up to two seconds are to allow for the execution of the appropriate actions to intitiate the reject.
'V1 must be respected as the latest speed by which a decision to stop must have been taken to assure a stopping capability within the distance available on a limiting runway'.
Thus, there is no 'thinking time' available after V1. My point about an FO calling a problem, say, five knots prior to V1, and thus setting in place a reject which occurs at a speed greater than V1, stands firm. Sorry, Checkboard, you need a re-think.
Source: AIC 141/1998 (Pink 182).
[This message has been edited by Captain Tobias Wilcox (edited 29 October 2000).]
[This message has been edited by Captain Tobias Wilcox (edited 29 October 2000).]
Guest
Posts: n/a
I am with Tobias on all counts. If the pilot driving the thing is the F/O he will generally have a quicker reaction time to the command 'STOP' from the Captain, than is the case if the Captain has to assess, take control of steering etc and close throttles, apply wheelbrakes, select reverse, spoilers or whatever is appropriate. Also, in the case of the F/O handling the T/O and feeling something very obviously wrong with the controls or steering, there may not be time to communicate this feeling in suitable words to give the Captain the info he needs to take over. Up to V1 you may well get the very rare spurious abort with the concomitant costs, but how often really?
In training we seem to think only of engine failures or firewarnings, but what about jammed controls, unexplained buffetting, blown tyres (not necessarily a reason to abort, but training should cover this), multiple bird strikes, aquaplaning etc etc? When the Captain is flying, he can always make his own instant decision if it feels wrong, or heed the F/O's call, or choose to ignore it. The only difference when the F/O is flying is that he MUST react to the Captain's command to stop, and once maybe in his entire career he may make a wrong decision to abort....go back to my earlier comment above. As long as no one's hands are on the throttles after the V1 call, an over run would be a pretty rare event, and that is what training is all about. For those operators who always have the Captain hold the throttles for T/O, run some subtle incapicitation exercises and slow reaction exercises in the simulator and you will maybe see the wisdom of training for all scenarios and giving the levers to the F/O for his/her takeoff, ditto the nosewheel steering if it is fitted to the RHS and needed for the T/O. My current employer has the Captain take over the levers after initial thrust is set, and will never change, but that doesn't make it the best procedure, although in our operation it is safe enough. Fortunately our runways rarely put us right on the balanced field numbers and we never encounter slippery or very wet runways.
In training we seem to think only of engine failures or firewarnings, but what about jammed controls, unexplained buffetting, blown tyres (not necessarily a reason to abort, but training should cover this), multiple bird strikes, aquaplaning etc etc? When the Captain is flying, he can always make his own instant decision if it feels wrong, or heed the F/O's call, or choose to ignore it. The only difference when the F/O is flying is that he MUST react to the Captain's command to stop, and once maybe in his entire career he may make a wrong decision to abort....go back to my earlier comment above. As long as no one's hands are on the throttles after the V1 call, an over run would be a pretty rare event, and that is what training is all about. For those operators who always have the Captain hold the throttles for T/O, run some subtle incapicitation exercises and slow reaction exercises in the simulator and you will maybe see the wisdom of training for all scenarios and giving the levers to the F/O for his/her takeoff, ditto the nosewheel steering if it is fitted to the RHS and needed for the T/O. My current employer has the Captain take over the levers after initial thrust is set, and will never change, but that doesn't make it the best procedure, although in our operation it is safe enough. Fortunately our runways rarely put us right on the balanced field numbers and we never encounter slippery or very wet runways.
Guest
Posts: n/a
Two further points:
First, if you flex to minimum thrust on every take-off, you are putting yourself at very much greater statistical risk of a disastrous late reject.
Second, and perhaps by way of advice to FOs reading this who felt left out by my earlier post, if you are handling the take-off but the Captain's hand is on the thrust levers, and you genuinely feel without doubt that a reject is absolutely necessary NOW, then you could consider placing your hand above the Captain's on the thrust levers, and retarding them. This might have to be done very forcefully, and you should shout 'STOP' with real meaning in it.
You might be out of a job, and you may never get a job again, but at least you'll live. If you do consder this as an option, you should be prepared to carry out all the subsequent reject actions correctly, too, as your colleague may react unpredictably.
I do, of course, recognise that this is a point of view with which many people will take issue. However, bearing in mind the frequency with which incapacitation occurs, it is worth considering that if the Captain is responsible for deciding to stop, and he fails to make this decision with split-second accuracy, then he is, in a way, incapacitated - he has failed to do what is necessary to safeguard the aircraft. This is not an impossible scenario, and FOs at all levels of experience should be prepared for it.
First, if you flex to minimum thrust on every take-off, you are putting yourself at very much greater statistical risk of a disastrous late reject.
Second, and perhaps by way of advice to FOs reading this who felt left out by my earlier post, if you are handling the take-off but the Captain's hand is on the thrust levers, and you genuinely feel without doubt that a reject is absolutely necessary NOW, then you could consider placing your hand above the Captain's on the thrust levers, and retarding them. This might have to be done very forcefully, and you should shout 'STOP' with real meaning in it.
You might be out of a job, and you may never get a job again, but at least you'll live. If you do consder this as an option, you should be prepared to carry out all the subsequent reject actions correctly, too, as your colleague may react unpredictably.
I do, of course, recognise that this is a point of view with which many people will take issue. However, bearing in mind the frequency with which incapacitation occurs, it is worth considering that if the Captain is responsible for deciding to stop, and he fails to make this decision with split-second accuracy, then he is, in a way, incapacitated - he has failed to do what is necessary to safeguard the aircraft. This is not an impossible scenario, and FOs at all levels of experience should be prepared for it.
Guest
Posts: n/a
Capt. Tobius W.
You say in your post "But at least you'll live". Well, I think you need to think that statement through carefully. It's all hypothetical of course (thank God) because the potential for sheer confusion would be greatly increased if you tried to claw back control from the captain who would understandably think you had gone off your trolley. Throw V1 out of the window - -I perceive a serious problem and bugger the captain - I'm taking over and aborting. Ooops! Sorry captain! I'm over-running the strip - handing over, you old fool.
While the above comments are my weak idea of a joke, it could be serious if the captain is suddenly over-ruled in a late go/no go decision.
I am sensitive on this one, because it happened to me on a limiting length take off in a 737-200 on a Pacific island. My take off. The over-run area didn't bear thinking about - huge rocks forming a sea-wall literally 10 metres from end of runway.
20 knots below V1, the F/O calls that the left EPR has gone ape and that we are overboosting to blazes. He attempts to drag back the throttle from under my hand in order to even up the EPR to 2.18 (planned take off setting)
The N1 were both normal at around 98% and no asymmetric yaw, apart from that caused by F/O trying to tug back throttle. Told F/O to let go throttle and that N1 were both OK, so no problem that we couldn't sort out in the climb when flaps were up and after take off scan done.
F/O still tried to pull back throttle from under my hand, and I had to resort to snapping at him hard to get his hand of the throttle as it was a battle of wills at a critical time. That worked, and the F/O has hated my guts ever since that episode. He is a 747 captain now. But I was right. We later found that the Pt2 inlet tube for that engine had become contaminated and led to false over-read of the EPR gauge. Remember the Potomac accident.
There are a countless scenarios that you can dredge up on take off where immediate action by either crew member might save the day. But you cannot cover them all, as the situation depends on too many variables. In the end a compromise must be struck. And that is that the captain is paid and trained to take full responsibility for whatever action he deems necessary to ensure the safest result. But because a first officer decides in his wisdom to take over at a late stage of a critical take off, does not necessarily mean that we will all live. That part is always in the lap of the Gods.
You say in your post "But at least you'll live". Well, I think you need to think that statement through carefully. It's all hypothetical of course (thank God) because the potential for sheer confusion would be greatly increased if you tried to claw back control from the captain who would understandably think you had gone off your trolley. Throw V1 out of the window - -I perceive a serious problem and bugger the captain - I'm taking over and aborting. Ooops! Sorry captain! I'm over-running the strip - handing over, you old fool.
While the above comments are my weak idea of a joke, it could be serious if the captain is suddenly over-ruled in a late go/no go decision.
I am sensitive on this one, because it happened to me on a limiting length take off in a 737-200 on a Pacific island. My take off. The over-run area didn't bear thinking about - huge rocks forming a sea-wall literally 10 metres from end of runway.
20 knots below V1, the F/O calls that the left EPR has gone ape and that we are overboosting to blazes. He attempts to drag back the throttle from under my hand in order to even up the EPR to 2.18 (planned take off setting)
The N1 were both normal at around 98% and no asymmetric yaw, apart from that caused by F/O trying to tug back throttle. Told F/O to let go throttle and that N1 were both OK, so no problem that we couldn't sort out in the climb when flaps were up and after take off scan done.
F/O still tried to pull back throttle from under my hand, and I had to resort to snapping at him hard to get his hand of the throttle as it was a battle of wills at a critical time. That worked, and the F/O has hated my guts ever since that episode. He is a 747 captain now. But I was right. We later found that the Pt2 inlet tube for that engine had become contaminated and led to false over-read of the EPR gauge. Remember the Potomac accident.
There are a countless scenarios that you can dredge up on take off where immediate action by either crew member might save the day. But you cannot cover them all, as the situation depends on too many variables. In the end a compromise must be struck. And that is that the captain is paid and trained to take full responsibility for whatever action he deems necessary to ensure the safest result. But because a first officer decides in his wisdom to take over at a late stage of a critical take off, does not necessarily mean that we will all live. That part is always in the lap of the Gods.
Guest
Posts: n/a
Hi guys & galls. Sorry for the late reply but been on holidays (yes that is still possible in our company). Thanks for all the answers, especially CTW for your elaborate thinking the problem out. On most points I agree with you, only I wouldn’t like an eager FO go over my hands if he thinks I’m incapacitated while I just might be putting these little grey cells of mine to work.
As I see it there are three main procedures (with variations among them):
1- The FO does the complete take off and if necessary the reject.
2- The FO does the take off ,the captain handles the throttles and takes control of the A/C in case of a reject.
3- The FO does the take off and the initial thrust setting, after thrust is set the captain takes over the throttles (around 80 kts). This is the procedure described by Boeing.
The take off is a critical flight phase especially when a RTO decision has to be made. This is why the procedure should be SIMPLE, CLEAR and UNAMBIGUOUS. Most points about the (dis)-advantages of the various procedures have been made by you all so I won’t repeat them.
Regarding point 1 I would even consider to let the FO have the authority to abort in the following 4 cases: -Engine Failure
-Fire Warning
-Take Off warning
-Controllability problems.
These cases are clear-cut and any pilot should stop for them. As the FO is looking outside he can only react to what he hears or feels. The captain can always call STOP if anything else goes wrong, for which he thinks an abort is advisable. If he is go minded he should give the V1 call timely so the FO hands are off the throttles as V1 is reached.
My main objection to procedure 2 and 3 is that at any time a control change is taking place during the roll.
My other point is against a change in procedures. Whatever procedure is used in your company initially stick to it! When the sh.. hits the fan and the split second decision has to be made, people act like monkeys to the procedures that have been enforced for years. As younger people adapt more easily to change than the “less younger” ones (thus mostly the captains), there is room for Mr Murpy to creep in and certainly an abort gone wrong is gonna happen.
Safe flying to you all.
As I see it there are three main procedures (with variations among them):
1- The FO does the complete take off and if necessary the reject.
2- The FO does the take off ,the captain handles the throttles and takes control of the A/C in case of a reject.
3- The FO does the take off and the initial thrust setting, after thrust is set the captain takes over the throttles (around 80 kts). This is the procedure described by Boeing.
The take off is a critical flight phase especially when a RTO decision has to be made. This is why the procedure should be SIMPLE, CLEAR and UNAMBIGUOUS. Most points about the (dis)-advantages of the various procedures have been made by you all so I won’t repeat them.
Regarding point 1 I would even consider to let the FO have the authority to abort in the following 4 cases: -Engine Failure
-Fire Warning
-Take Off warning
-Controllability problems.
These cases are clear-cut and any pilot should stop for them. As the FO is looking outside he can only react to what he hears or feels. The captain can always call STOP if anything else goes wrong, for which he thinks an abort is advisable. If he is go minded he should give the V1 call timely so the FO hands are off the throttles as V1 is reached.
My main objection to procedure 2 and 3 is that at any time a control change is taking place during the roll.
My other point is against a change in procedures. Whatever procedure is used in your company initially stick to it! When the sh.. hits the fan and the split second decision has to be made, people act like monkeys to the procedures that have been enforced for years. As younger people adapt more easily to change than the “less younger” ones (thus mostly the captains), there is room for Mr Murpy to creep in and certainly an abort gone wrong is gonna happen.
Safe flying to you all.
Guest
Posts: n/a
Centauraus,
At least you didn't have the problems your colleagues experienced which made such interesting reading in the 'new' Australian 'crash mag'.
Your point is well taken, but, (and it's going to be hard to get this across without seeming to criticise):
First, you had a tech problem which (I guess) manifested itself at just the wrong time (on the take-off roll at a high speed). You were exceedingly unlucky.
Secondly, your FO had not been trained and tested to a high enough standard. I cannot emphasise enough that good procedures only work with competent crews. Your FO did not check the other indications to confirm the problem, and was therefore not 'competent'.
Assuming that you stated clearly to him that there was no need to retard the lever, he also failed to be 'competent' in checking that his own perception of the situation was correct before attempting to take action a second time.
Train 'em,
test 'em,
trust 'em.
And do it all to a very high standard.
At least you didn't have the problems your colleagues experienced which made such interesting reading in the 'new' Australian 'crash mag'.
Your point is well taken, but, (and it's going to be hard to get this across without seeming to criticise):
First, you had a tech problem which (I guess) manifested itself at just the wrong time (on the take-off roll at a high speed). You were exceedingly unlucky.
Secondly, your FO had not been trained and tested to a high enough standard. I cannot emphasise enough that good procedures only work with competent crews. Your FO did not check the other indications to confirm the problem, and was therefore not 'competent'.
Assuming that you stated clearly to him that there was no need to retard the lever, he also failed to be 'competent' in checking that his own perception of the situation was correct before attempting to take action a second time.
Train 'em,
test 'em,
trust 'em.
And do it all to a very high standard.
Guest
Posts: n/a
On my jet, both the Captain and the Flt Eng have their hands on the power levers, but the Flt eng has his own set on his panel! He also has the only EPR guages, the pilots only have N1 guages (the main power reference on the jet). Either pilot or the eng can call the RTO, and either the captain or the eng closes the power levers. The FO never touches the power levers, even when PF, as the eng sets power on the PFs command.
Odd, but it works well.
[This message has been edited by Dan Winterland (edited 04 November 2000).]
Odd, but it works well.
[This message has been edited by Dan Winterland (edited 04 November 2000).]
Guest
Posts: n/a
RTO, ok first of all be go minded, too many accidents have occured from RTO beyond V1, even some with the nose gear off the ground.
From 1959 to 1990 there have been 74 RTO overrun accidents in western jet aircraft, resulting in 400 fatalities, 58 % of theese the RTO was initiated above V1.
The Captain has to guard the Thrust Levers, since it is ultimately his responsibility to decide stop or go, even if the FO is PF, and in my experience there is no problem in taking over the controls form the FO.
Especially with new FO´s they tend to have less excess capacity to analyze the situation during TO.
The main stopping agent in an RTO is the wheel brakes, manually or autobrake in RTO, these must be used maximum all the way till the aircraft comes to a "rocking stop"
Next comes reverse and spoilers, the spoilers increase drag, but more significantly increases weight on wheels thus increasing brake performance.
Thus a tire burst before V1 should NOT lead to a RTO, since the stopping capability with a damaged tyres is next to none, and an overrun is almost certain. On the other hand a prepared landing with damaged tyres, can performed safely.
RTO is a complex decision, with only litte time available, naturally it is the Commanders.
KG
From 1959 to 1990 there have been 74 RTO overrun accidents in western jet aircraft, resulting in 400 fatalities, 58 % of theese the RTO was initiated above V1.
The Captain has to guard the Thrust Levers, since it is ultimately his responsibility to decide stop or go, even if the FO is PF, and in my experience there is no problem in taking over the controls form the FO.
Especially with new FO´s they tend to have less excess capacity to analyze the situation during TO.
The main stopping agent in an RTO is the wheel brakes, manually or autobrake in RTO, these must be used maximum all the way till the aircraft comes to a "rocking stop"
Next comes reverse and spoilers, the spoilers increase drag, but more significantly increases weight on wheels thus increasing brake performance.
Thus a tire burst before V1 should NOT lead to a RTO, since the stopping capability with a damaged tyres is next to none, and an overrun is almost certain. On the other hand a prepared landing with damaged tyres, can performed safely.
RTO is a complex decision, with only litte time available, naturally it is the Commanders.
KG
Guest
Posts: n/a
In our British short-haul airline, for a RHS take-off (on the 737), the F/O sets approx 40%, Capt calls “stable”, then F/O presses TOGA and removes left hand from thrust lever back to the control column. Capt then covers the thrust levers until V1 which are normally moved to the take-off thrust setting by the autothrottle.
The Captain will be monitoring the engine instruments & aircraft performance throughout the take-off roll whilst the F/O is concentrating on flying the aircraft, he (the F/O) only looks in to cross-check the ASI calls. Therefore the Captain is better placed to make the go/no go decision than the F/O and, as he is guarding the thrust levers he can immediately initiate the procedure if required. The F/O’s actions in an RTO include keeping the nose-wheel in contact with the runway and the wings level, both of which require both hands on the control column, which is where they are.
The procedure is slightly more tricky for a LHS take-off where the Captain flies with the left hand and covers with the right, but with his experience this is not a problem. The F/O will be making the speed calls, watching the engine instruments and is poised like a coiled spring to assist with the control column actions in the event of an RTO. Again the Capt makes the call as his hand is on the levers. Note that the speedbrake is on the LHS of the throttle quadrant so would be more difficult for the F/O to deploy. This system works fine in the sim and although I have not yet had one for real, I was as happy with it as an F/O as I am now as a Captain.
“STOP” is the biggest call you will ever have to make in your career and it would not be fair to the F/O or the pax to delegate this away from the most experienced crew member.
As an aside, Tobias said
“First, if you flex to minimum thrust on every take-off, you are putting yourself at very much greater statistical risk of a disastrous late reject”
It is worth mentioning that using a reduced thrust take-off will put less stress on the engine thereby reducing your chances of having the engine failure in the first place, but I am sure this has been discussed elsewhere at great length.
S & L
The Captain will be monitoring the engine instruments & aircraft performance throughout the take-off roll whilst the F/O is concentrating on flying the aircraft, he (the F/O) only looks in to cross-check the ASI calls. Therefore the Captain is better placed to make the go/no go decision than the F/O and, as he is guarding the thrust levers he can immediately initiate the procedure if required. The F/O’s actions in an RTO include keeping the nose-wheel in contact with the runway and the wings level, both of which require both hands on the control column, which is where they are.
The procedure is slightly more tricky for a LHS take-off where the Captain flies with the left hand and covers with the right, but with his experience this is not a problem. The F/O will be making the speed calls, watching the engine instruments and is poised like a coiled spring to assist with the control column actions in the event of an RTO. Again the Capt makes the call as his hand is on the levers. Note that the speedbrake is on the LHS of the throttle quadrant so would be more difficult for the F/O to deploy. This system works fine in the sim and although I have not yet had one for real, I was as happy with it as an F/O as I am now as a Captain.
“STOP” is the biggest call you will ever have to make in your career and it would not be fair to the F/O or the pax to delegate this away from the most experienced crew member.
As an aside, Tobias said
“First, if you flex to minimum thrust on every take-off, you are putting yourself at very much greater statistical risk of a disastrous late reject”
It is worth mentioning that using a reduced thrust take-off will put less stress on the engine thereby reducing your chances of having the engine failure in the first place, but I am sure this has been discussed elsewhere at great length.
S & L
Guest
Posts: n/a
Yes it has, but consider:
The consequences of an engine failure are likely to be a period of high workload followed by a safe landing.
The consequences of a tardy decision to stop in limiting circumstances are a definite overrun, casualties, and perhaps a hull loss.
I know which I prefer.
Also, my view is that the take-off maneouvre is so important, that it's not fair on the FO or the passengers not to have both pilots fully involved and both with the right to call the whole thing off if they don't like it. Legally, by the way, this is the case, as discussed earlier concerning incapacitation.
The consequences of an engine failure are likely to be a period of high workload followed by a safe landing.
The consequences of a tardy decision to stop in limiting circumstances are a definite overrun, casualties, and perhaps a hull loss.
I know which I prefer.
Also, my view is that the take-off maneouvre is so important, that it's not fair on the FO or the passengers not to have both pilots fully involved and both with the right to call the whole thing off if they don't like it. Legally, by the way, this is the case, as discussed earlier concerning incapacitation.
