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P2 Engine handling.

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P2 Engine handling.

Old 23rd Nov 2022, 19:18
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P2 Engine handling.

I’ve noticed in some flight deck videos during take off P2 handling, the Captain handles the Thrust Levers. Do some airlines have SOPs preventing P2 from rejecting the takeoff?
In my airline when it is a copilot’s handling sector, the P2 handles the aircraft from start up to parking. (Except during the Monitored Approach SOP)
The P2 handles his own Thrust Levers and can reject the take off if .required. The Capt of course can call Stop at any time.
But it appears the second in command is not trusted to call an RTO in several airlines.
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Old 23rd Nov 2022, 20:20
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Carefully worded it is.
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Old 23rd Nov 2022, 20:55
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Do some airlines have SOPs preventing P2 from rejecting the takeoff?
The vast majority of the worlds airlines follow the recommendation of both Boeing and Airbus which is that the P1 should make the decision and handle the RTO.
BA (who you presumably work for, as do I) for reasons which have I never heard fully explained or justified, choose not to.

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Old 23rd Nov 2022, 21:40
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Some airplanes (like the 737 with it's three-step RTO manuever) have a disadvantage when it comes to handling the RTO from the RHS, so it makes sense that the captain will perform the RTO.

Typically the captain will be the most experienced pilot on the flight deck and (typically) the person to make the best judged decision to perform an RTO or not. Unlike a go-around, an RTO is not always the safest option and can easily lead to the aircraft going to the valley beyond the end of the runway in some scenarios, even when rejecting well below V1. You'd want the most experienced person performing that decision whether to reject or not, based on the input from the FO side as well, of course.
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Old 24th Nov 2022, 09:09
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Typically the captain will be the most experienced pilot on the flight deck

More importantly, the buck stops with the PIC so he/she should be the one to do the deed, aircraft systems permitting.
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Old 24th Nov 2022, 09:42
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Any rumors who else apart from BA deleagtes the (non-reversible) action to SIC?

Because it is not Boeing and Airbus recommendation, it's the established standard of doing things.
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Old 24th Nov 2022, 12:27
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I would like to think that the reason for the SOP, is BA selects and trains it's P2s to the high standard required. They even let the P2 taxi the a/c! Some operators do not, even with RHS steering fitted.
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Old 24th Nov 2022, 12:34
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Be that as it may, going against a manufacturer's recommendation is very hard to explain to your insurance in case of an incident...

Apart from that - I'd hope that every company trains both pilots to the same standard!
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Old 24th Nov 2022, 12:34
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But I suppose not to the high enough standard to let the PF select thrust reversers on landing?
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Old 24th Nov 2022, 13:51
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Or to make a decision at minima. Or take the correct decision at minima after they had become captains. 👀
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Old 24th Nov 2022, 14:27
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The issue of P2 Takeoff is a bit complicated. The recommended training for it is called seat oriented. CM1 is trained to take decision and carry out the reject. The CM2 who becomes PF is only trained to do PM duties on a reject. So there's a role reversal at a critical time. Especially in a low speed reject where the full rudder and sliding the foot up for differential braking may be required any delay and excursion is a reality. In another real life incident Captain taking off in 737 at 114kts. his back rest collapsed and the backward movement caused throttles being pulled backed by 20% N1 which they didn't notice. He promptly handed over controls to copilot. Copilot not trained in PF duties in a reject just kept the aircraft straight. The V1 was 144kts correct decision for copilot trained to reject would have been to stop. The capt recovered, took over controls and carried out the take off but due to the reduced thrust aircraft got airborne beyond the available runway length hitting the boundary wall. Luckily they got away with minor damage. In my opinion copilot also needs to have ability to reject.
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Old 24th Nov 2022, 15:03
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It is an interesting discussion. In all airlines i flew in the decision to reject a take off was and is only up to the captain. However back in a previous airline when we switched from our in house SOP to Airbus SOPs, which included the FO starting engines, taxying and parking the aircraft (if the parking system allowed it), the question came up if the FO should have the authority to reject a take off as well. Some trainers tested that in the spare time in normal simulators, a few go/no-go decisions by the Captain and then the same for the FO. One thing stood out, that every FO rejected a take off for a sudden emergency electric configuration which ended with a high speed runway excursion. Not necessarily very scientific, but it put that topic to rest.

Personally i am undecided. We trust FOs with nearly everything else in many airlines, but not with the go / no-go decision.
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Old 24th Nov 2022, 15:15
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Of those choosing Captain action for all RTOs, how do procedures account for the time taken in communicating, reassessment, and then acting in change of control with respect to the definition of V1 (first stopping action commenced), and thence any effect in the already scan margins in stopping distance.
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Old 24th Nov 2022, 15:20
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Captain has his hands on the tiller and throttles and feet on the pedals if FO is PTakingoff.

Change of control is implied at captain's call of stop, no real "handover" of control is required.
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Old 24th Nov 2022, 16:05
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CM, thanks.

However, there will be a time difference between a 'hands on thrust' identification and self action, vs communicating the identification, and subsequent action by whoever, after confirmation; i.e P2 handling, deciding and acting, will be faster than alerting, waiting for Captain's mental appreciation, and then either acting.

Cognitive delays; small but important where there is little margin.

Then there is cognitive dissidence. P2 calls stop, Capt says no - continue; who has physical control, who has a suitable mental appreciation of actions required during a continued takeoff.

PF flys, PM monitors the overall situation; - why then change the SoP in specific circumstances - which implies that the circumstance can be identified - unnecessary mental workload ?
e.g. a confirmable engine failure or just a bang, a gut feeling, uncertainty how, who decides.
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Old 24th Nov 2022, 17:07
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Originally Posted by safetypee View Post
CM, thanks.

However, there will be a time difference between a 'hands on thrust' identification and self action, vs communicating the identification, and subsequent action by whoever, after confirmation; i.e P2 handling, deciding and acting, will be faster than alerting, waiting for Captain's mental appreciation, and then either acting.
The captain decides and acts; I'm not seeing the extra time involved.

Is the edge case you're thinking of that an engine quits and the FO controls the rudder so fast and perfect that there is no yaw, and the Captain's feet are on the floor so he doesn't know and needs to be told? I suppose in this one, there would be a difference.

Then there is cognitive dissidence. P2 calls stop, Capt says no - continue; who has physical control, who has a suitable mental appreciation of actions required during a continued takeoff.
The P2 doesn't call stop, and doesn't get invested into a course of action that is then reversed.

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Old 24th Nov 2022, 17:27
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IL thanks,
In the first instance where the Captain decides and acts, it is assumed that s/he has recognised the situation. If not, then the P2's alert (as a handling PM !) starts the Capts time consuming assessment, decision, and action.

Re 'stop'; yes I assumed a decision.
An alert as above is more relevant, but the opportunity for dissidence remains - thoughts opposed to actions, although the latter is a risk with over emphasised assertive training - CRM.

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Old 24th Nov 2022, 18:57
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You are coming across as extremely hard to understand this time, ST. Please don't assume people are in agreement with your observations just because there is little or no objection or additional details coming from the others.

While your logic is usually flawless, you seem to be applying it at an odd angle to reality here, which is a simple and well-established procedure.

The decision is done by the PIC and since he has hands on the THR LVRs he will act accordingly. The rest of the crew is advised as a first priority as the situation unfolds. Typically FO don't need to be told a rejected manoeuvre is taking place, however, the call-out triggers the action sequence for everyone.

For the FO the responsibility is to clearly announce what he sees, such as "unreliable airspeed" (GO decision but only above 100 kts) or "engine fire". Cue here, by the time the F/O sees an alert coming up with bells and whistles, the PIC can hear that too and proper circuitry gets energized.

My personal CP:FO hrs ratio is 1:2 so not that experienced left seater at all. Total flight time is about 5:1 over the average company FO. In most training events I will recognize and call out a non-announced failure (engine spool down) faster than my colleagues while being the PF. Not by skill but by previous training exposure (and I keep 1 eye head down which is by no means a dogmatic technique). Four edge cases:
- FO incapacitation approaching 100 ktś (lo-speed and hi-speed borderline)
- tyre burst
- loss of visual reference above 100 kts
- airspeed discrepancy affecting the CM1 side.

The current recipe works without leaving major gaps exposed.

I am sure BA researched their SOP with great patience and train to proficiency. Exactly: their much famed monitored approach (slast will elaborate though probably you knew each other before my birthday) puts the decision to GA on the PnH, because he is better suited to evaluate. That's what happens during take-off when the PF = FO = RHS and the PIC makes the failure announcement, takes the decision, and calls out the manoeuvre as his hand moves the thrust levers. To save time and avoid confusion the hand is placed there once TO THR is achieved.



Last edited by FlightDetent; 24th Nov 2022 at 21:36.
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Old 24th Nov 2022, 19:24
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FD, I agree with your views; my devilment looked for the detail.

An objective was to test the reasoning behind some of the procedures, how people think about remote possibilities, and the possibility that in such situations there is no unique answer.
A conclusion could be to decide which pilot will have the better detection and awareness, if not necessarily the better judgement, then who acts, when, in a rare time critical situation.

I would not challenge any particular operation without knowledge of their reasoning behind it, but concern remains about many unsatisfactory outcomes when apparently good plans and procedure exist.

It doesn't matter who does it, provided it is done as well as possible in the situation.
The situation, context is everything; focus on that.

Re Steve, monitored approach, we have corresponded; agreement in part, but again it depends on context.
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Old 24th Nov 2022, 20:11
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Originally Posted by safetypee View Post
IL thanks,
In the first instance where the Captain decides and acts, it is assumed that s/he has recognised the situation. If not, then the P2's alert (as a handling PM !) starts the Capts time consuming assessment, decision, and action.
I always (from the West side of the Atlantic) thought P1 means Captain and P2 means FO. Before we continue, is this right? Honest question. If so, then the only way I can interpret your phrase "P2's alert (as a handling PM)" is a tongue in cheek note that under the system of only CA aborting, the P2/FO (while handling/PF) is simultaneously being saddled with the other's role as PM and thus overloading him and making him ineffective (while leaving the CA doing nothing.) Well, if we take that PM role off of that pilot and put it in the left seat, then we have the CA/P1 doing the PM job (which is the actual case), thus equipping him perfectly to do the assessment and decision with no clock needing to be started by the other seat.

Are there any scenarios that have a significant chance of going unnoticed by the Captain so that he's reliant on the FO telling him?

Who has the wider scope of attention available to look at the engine instruments, and caution/warning system, and overall totality of the situation, and integrate all of these things into a decision?

Re 'stop'; yes I assumed a decision.
An alert as above is more relevant, but the opportunity for dissidence remains - thoughts opposed to actions, although the latter is a risk with over emphasised assertive training - CRM.
If there's cognitive dissonance on the part of the FO or they get locked into some decision tree that is too complicated to make the right call in a second, and I'm riding in the back, I would sure hope the system is designed around defaulting to simply continuing what's already happening, and completing the in-progress maneuver as is already habit over dozens or hundreds or thousands of repetitions in normal flying; and not triggering a high speed abort based off that.
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