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B777 single engine go around and TOGA switches

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B777 single engine go around and TOGA switches

Old 5th Jul 2021, 06:05
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There was an incident in Australia a few years ago where an A320 crew attempted to go around from the minima when not visual. Except they didn’t push the thrust levers through the gate. Very exciting moments accelerating toward the runway until they figured out what was happening.
TOGA works just fine.
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Old 5th Jul 2021, 06:06
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Other considerations

Both thrust levers could easily be at idle

One TOGA switch could be inoperative

It’s not unheard of for crew to grab the incorrect lever.
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Old 5th Jul 2021, 06:30
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​​​​​A Go around is not a good place to be when you don't have OEI protections that are provided by the approach climb criteria... here in the US we have an approach climb protection for both OEI or AEO.
​​​​Landing climb is predicated on AEO. Just a friendly reminder
​​​​

Last edited by Pugilistic Animus; 17th Jul 2021 at 07:37.
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Old 5th Jul 2021, 08:52
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BuzzBox

can’t remember, I think there was a time on the missed approach or engine failure after V1 where CLB CON was called for..wish I still had my 777 to fly, that was a hell of a machine
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Old 5th Jul 2021, 09:42
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I could never understand the move from the rear of the thrust lever G/A switches as on the 757/767 to the front of the thrust levers as in the 777.A great number of pilots would graduate from the former to the latter which may confuse at a critical phase of flight.If if aint broke don't fix it springs to mind.
Just an observation.
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Old 5th Jul 2021, 11:16
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For your benefit and not mine....

Either TOGA switch. But note that if SE the live engine will likely be positioned forward and thats the one you will have your hand on, the dead engine lever will be at idle and difficult to access unless you can somehow reach back with your extra long fingers to reach the switch, and why would you do that anyway. If the live engine TOGA switch fails, (which I think is why you are asking) the other one I guess would work but its position may be an issue.

Re position..TOGA switches are paddles in front of and below the thrust levers and are activated using your fingers by reaching over the thrust knobs, the switches on the side of the thrust levers are AT switches on the 777 not GA switches as in some other types......often confused by those who came off AC with that configuration. Attempted GA by disconnecting the AT instead of activating TOGA is an interesting concept.

ALWAYS follow through with thrust levers as TOGA switches may fail (so press both anyway if you have both engines operating) AND be aware that TOGA mode is not available on the ground if you have touched down already. (ie 777 accident in Dubai). If TOGA is not available for whatever reason then the AP/FD will remain in whatever mode it was in, ie LOC/GS or VNAV/LNAV and will not increase thrust or command the pitch attitude required for GA. The only option therefore is to disconnect the AP, and apply thrust manually, pitch up manually against the FD then turn FDs off to avoid distraction. (easier said than done, and especially difficult at low level if on one engine in IMC). Note that if the AP remains engaged and you just manually apply thrust the aircraft will accelerate down the runway without climbing as it is attempting to land but cannot due to the higher speed.

Re performance the SE and 2 ENG cases are checked to meet regulatory requirements but this does not guarantee terrain clearance at your particular airport. The LANDING CLIMB LIMIT WEIGHT table in the QRH checks both SE and 2 ENG cases ie a minimum climb gradient of 2.1% S.ENG/F20/GR UP and 3.2% 2 ENG/F25-30/GR DN.

SE case is always the most limiting. The table is based on F20 so depending on configuration you may have F5 for a SE GA in which case you may get slightly better performance. However the 2.1% that it checks does not give obstacle clearance as 2.5% is required for PANOPs and 3.3% for TERPS charts plus another 0.6 if turns are involved.

To check if you have sufficient performance for the airport you are flying into can be done by entering the required gradient into the OPT and it will tell you if it can be achieved or not. If it cannot be achieved you can still do the approach by opting to fly the engine out escape maneuver OR commit to land.

Re previous post about CON, CON power is less than TOGA and probably wont cut it on one engine, and in any case is not correct. CON would be selected after the GA has been completed.

And for sake enough of the bitching...you're like a bunch of sheila's !
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Old 5th Jul 2021, 14:07
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TukwillaFlyboy

That is due to wrong habits maybe from earlier aircraft. Also due arbitrary change of SOP by the airline not to immediately check FMA but only after gear up, which they reverted back after the incident. In Airbus you don't nurse thrust levers to TOGA you just hit the stop. It's FADEC controlled and FBW levers. Same procedure even after touchdown unlike Boeing. No confusion
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Old 5th Jul 2021, 15:39
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Can the 777 auto throttle be used single engine ?

If so, then with habit of not following-up with hands-on, the reach for TOGA switch would be unusual; quick hand movement anticipating two hands on the wheel for manual GA.

Slight similarities with prior 777 accident - no GA due to low rad alt (design), weakness in checking annunciation, and poor feel - feedback from TOGA switch if not used very often.
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Old 5th Jul 2021, 16:53
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'Can the 777 auto throttle be used single engine' - yes and would normally be used if available.
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Old 6th Jul 2021, 01:02
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This is where call-outs become important. After pressing TOGA switch in a go-around, FMA change to TOGA and should be sighted and callout by pilot.
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Old 6th Jul 2021, 01:35
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No 777 experience, but there’s a lot of talk about failure of the TOGA switch, mode confusion etc.

I’ve only flown one plane with an Autothrust motor. My technique was either:

- push the levers forward, then click the TOGA switch

- push the levers forward while clicking the TOGA switches

I probably exercised that second option more often. The point being, I flew the plane first. Aviate, navigate, communicate, automate.
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Old 6th Jul 2021, 04:04
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Anyone have any idea why the TOGA switches were relocated?
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Old 6th Jul 2021, 05:59
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alf5071h

Alf. Why would you need two hands on the control wheel. A practice fraught with danger. Even with an active or inactive auto throttle there is only one place for the second hand, unless operating some other AFCS switch or knob, On the bloody thrust lever.

In the OEI situation, the retarded thrust lever makes a good rest for your wrist or hand while your fingers guard the live thrust lever. Unless you have infant sized hands.
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Old 6th Jul 2021, 06:20
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mattyj

CON thrust shouldn't be selected until after the aircraft has reached the acceleration altitude and the flaps have been retracted to the desired setting for the continued climb.
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Old 6th Jul 2021, 09:04
  #35 (permalink)  
 
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“Why would you need two hands on the control wheel. A practice fraught with danger.” … quite so …
I don't know, … not 777 rated.

Perhaps Ppruners, without fear of fault or ridicule, could answer this based on their experience, together with ‘because’, explaining why this is-is/not done, supporting opinion.

Everyone get two answers; that which is trained for; and that which is done … and why.
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Old 6th Jul 2021, 09:54
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1. One hand on the control column, the other on the thrust levers.
2. See above.

Why? Because it's good airmanship; no pilot should ever blindly rely upon the automation. Having your hand on the thrust levers might just save your bacon if the automation doesn't do what's expected.
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Old 6th Jul 2021, 10:17
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Is there any Boeing pilot out there has not been taught from day 1 not to follow up the thrust levers ?
Its Boeing one-o-one.
Its not that hard people.
FTFA
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Old 6th Jul 2021, 12:39
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Agreed. Left stick to turn left, push the thrust levers to climb, push the stick forward to get away from stall... stuff like that. The basic basics. Lot of other stuff built on top that eases life and increases efficiency, but if you pull out the foundation then the whole pile collapses. Don't lose the plot, folks.
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Old 6th Jul 2021, 18:51
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Re the TOGA switch failure it’s the sort of unlikely BS failure that smart arse sim instructors come up with to you about and waste 30min of checking (previously called training) time rather than emphasising the basics.

Re basics ....that sort of stuff went out years ago it’s all about being able to regurgitate the latest change to the SOPs and have hands, feet and mouth going in all directions in an attempt to comply to avoid being whacked over the knuckles with a huge stick.

We would be much much much safer if we were left to fly the aircraft without worrying about all that crap.
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Old 6th Jul 2021, 19:11
  #40 (permalink)  
 
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TukwillaFlyboy

I've done countless flight tests on Boeing aircraft - and observed many simulator sessions. The PF always has one hand on the thrust levers during the final approach/landing phases.
It's that sort of basic piloting skill that would have saved the Asiana 777 at SFO. I remain convinced that a major contributory factor in that accident was that the PF had recently crossed over from flying Airbus, without sufficient difference training (such as hammering in the need for follow the thrust levers during final approach/landing).
With the notable exception of the 787, the autothrottle system on Boeing aircraft is not designed or certified as 'flight critical' - but I bet they don't teach the pilots that part...
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