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Positive Rate

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Positive Rate

Old 28th Jun 2020, 06:09
  #21 (permalink)  
 
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V1 - Engine failure - Rotate -

With the various views and procedures above, how, if at all, are they changed - applied in the event of an engine failure just after V1.
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Old 28th Jun 2020, 09:44
  #22 (permalink)  
 
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Can’t help thinking there’s some over complicating going on. Can’t answer for the Airbus, but Mr Boeing’s FCTM states ‘Retract the landing gear after a positive rate of climb is indicated on the altimeter.’ No more, no less.

Yes there are secondary and peripheral clues - the click of the lever lock, the houses getting smaller etc but Mr Boeing is the master of the art of keeping things simple.

safetypee - the wording in the FCTM is identical for the EFTO case.

rgds
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Old 28th Jun 2020, 10:43
  #23 (permalink)  
 
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With 50% loss of thrust the acceleration is less so rate of rotation needs to be slower and to a lesser attitude 12.5 in Air bus. Other than that everything else is same. RA and VS increasing raise the gear.
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Old 28th Jun 2020, 12:32
  #24 (permalink)  
 
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Just make sure it is not a momentary spike on the V/S, that could end very badly indeed... And yes, seen it enough in the SIM.
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Old 28th Jun 2020, 21:45
  #25 (permalink)  
 
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The EK777 crew may have seen a positive rate on their altimeters but did they sense (sight, sound and touch) the G/A thrust coming on. Did it feel right.

Maybe Im too over cautious with the positive rate call but Im glad I take 1 second longer than the fastest pilot in my company.
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Old 29th Jun 2020, 09:32
  #26 (permalink)  
 
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The snag with the SOP of "positive RATE", is that the only cockpit instrument that gives a rate reading is the VSI/IVSI. Concentrating on the rate parameter might cause some pilots to only look at the rate indication, which might be false.

As the aircraft rotates, the static ports - usually situated around the front of the aircraft - will climb, even when the main gear is still on the runway, so this indication does not necessarily mean that the aircraft is climbing. Ditto the altimeter.

The Rad Alt aerials - on Airbus situated well behind the main gear - will inititally show a descent when the aircraft rotates.

Only when all three: VSI, Altimeter and Rad Alt are showing positive or increasing readings, can one be sure that the whole aircraft is climbing up above the runway. Take a moment to be sure all three indications are solid and not a momentary glitch, before calling positive CLIMB.

Another good reason for checking three instruments instead of one or two, is to check against a faulty instrument. All three should agree the aircraft is actually going up !
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Old 29th Jun 2020, 10:08
  #27 (permalink)  
 
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Originally Posted by Uplinker View Post
The snag with the SOP of "positive RATE", is

...

Take a moment to be sure all three indications are solid and not a momentary glitch, before calling positive CLIMB.
Your valid point about overreliance on one instrument aside, you should use the callout verbiage that your SOP specifies.
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Old 29th Jun 2020, 10:14
  #28 (permalink)  
 
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Identifying +ve climb is not a big issue. The real problem is understanding priorities. Gear is not something that is to be got rid of as quickly as possible. I can't think of any incident where raising gear quickly or out of turn saved a disaster. It's other way round. In EK case if gear wasn't retracted aircraft wouldn't have been written off. On GA it's power, pitch, flaps then gear. On a low GA you hit TOGA, small change of pitch flap gear are left as they are till you are climbing away. No attempt is made to avoid ground contact because gear is the only part that can take impact load. Tail strike is more damaging.
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Old 29th Jun 2020, 10:53
  #29 (permalink)  

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Originally Posted by Uplinker View Post
Only when all three: VSI, Altimeter and Rad Alt are showing positive or increasing readings, can one be sure that the whole aircraft is climbing up above the runway.
That's pushing personal / company habits too far. Sinner like me can tell, as long as it is other people who are guilty and not yours truly.

And also factually incorrect.

Last edited by FlightDetent; 29th Jun 2020 at 11:24.
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Old 29th Jun 2020, 11:20
  #30 (permalink)  
 
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It's a positive rate when the dog on the flightdeck starts trying to bite your hand


Last edited by Pugilistic Animus; 29th Jun 2020 at 11:50.
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Old 29th Jun 2020, 12:40
  #31 (permalink)  
 
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Dead Dog

dh, #22,
Same procedure checks and calls, but with an engine failure and a performance limited departure, the timing of the checks and altitude of gear retraction need to change.

vilas, 'Gear is not something that is to be got rid of as quickly as possible'; so what triggers the change in thinking with engine failure, … the dog,

but PA's dog dies with engine failure; surprise of the event, forget, revert to everyday habit.
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