Re: Dash-8 incorrect takeoff configuration.

From	Sylvia Else <sylvia@email.invalid>
Newsgroups	aus.aviation
Subject	Re: Dash-8 incorrect takeoff configuration.
Date	2025-01-24 21:59 +0800
Message-ID	<lvhkmqF8lmsU1@mid.individual.net> (permalink)
References	(1 earlier) <op.20sc59v9byq249@pvr2.lan> <lve051Fl5i1U1@mid.individual.net> <op.20tk2vlxbyq249@pvr2.lan> <lvgpdlF3t5nU2@mid.individual.net> <op.20vdh9dzbyq249@pvr2.lan>

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On 24-Jan-25 4:21 pm, Rod Speed wrote:
> Sylvia Else <sylvia@email.invalid> wrote
>> Rod Speed wrote
>>> Sylvia Else <sylvia@email.invalid> wrote
>>>> Rod Speed wrote
>>>>> Sylvia Else <sylvia@email.invalid> wrote
> 
>>>>>> https://www.atsb.gov.au/publications/investigation_reports/2025/report/ao-2024-038
> 
>>>>>> It's time all public transport aircraft had takeoff
>>>>>> performance  monitoring, no matter the size.
> 
>>>>> That isnt going to result in the problem  being
>>>>> fixed quickly enough  to  stop an accident
> 
>>>> Well before an abort becomes risky, the system has enough 
>>>> informationto  determine whether the crew calculated v1 and vr are 
>>>> correct,
> 
>>> Bullshit with that incorrect flaps setting.
> 
>>>> and whether  the aircraft will be able  toboth continue a takeoff, 
>>>> and stop, at v1.
> 
>>> Bullshit with that incorrect flaps setting, let alone
>>> tell the pilots that the flaps setting is wrong.
> 
>>>  It would make much more sense to compare the
>>> actual settings with that has been entered at the
>>> preflight config calculations and tell the pilots
>>> that they have not set what was required with
>>> flaps and boost etc before they actually applied
>>> takeoff power and not allow takeoff power to be
>>> applied before those were set correctly.
> 
>>>> It can issue an abort alert if not.
> 
>>>  See above
> 
>>>> This covers at least miscalculated v1, miscalculated vr, wrong 
>>>> thrust settings, wrong flap settings, starting from the wrong 
>>>> intersection, takeoff from the wrong runway, and no doubt others 
>>>> that I haven't even thought of.
> 
>>> It would be stupid to try to measure that while taking off
>>> instead of doing that before takeoff power is applied
> 
>>> Yes, there is also a different problem with the engines
>>> not being able to deliver the power they were assumed
>>> to be able to deliver the power they were supposed to
>>> be able to deliver in the preflight calculations, but that
>>> was not the case in the incident being discussed and
>>> it would be much easier to discover than much earlier
>>> in the takeoff run than V1 or VR
> 
>> The question the system needs to ask is "In the current configuration, 
>> with the measured acceleration [*], current airspeed, and current 
>> position on the current runway, can the aircraft reach the specified 
>> V1 at a point where it can continue the takeoff or abort, and will it 
>> be able to rotate at the specified Vr.
> 
> The problem with that approach is that is far too late
> during the takeoff run to be doing that by measurement
> when its much too late for the pilots to be fixing what
> the problem is, particularly when the engines arent
> actually performing the way they were meant to when
> the prefight calculations were done

There would be no expectation that the pilots would fix it. The idea is 
to abort the takeoff while that can still be done safely.
> 
> Like I said, it makes much more sense to check that
> the pilots have set what they have caculated nees to
> be set before takeoff power is allowed to be applied
> 
>> [*] This also gives a reasonable estimate of the mass, assuming that 
>> the engine thrust is as commanded, or the engine thrust assuming that 
>> the mass is as configured, and allows an abort alert if the mass, 
>> acceleration, and thrust are not consistent with each other.
> 
> Not reasible to measure that during the takeoff run before V1

Why not?

Sylvia.

Thread

Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-21 13:28 +0800
  Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-23 04:21 +1100
    Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-23 12:50 +0800
      Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-23 20:09 +1100
        Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-24 14:14 +0800
          Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-24 19:21 +1100
            Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-24 21:59 +0800
              Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-25 03:46 +1100
              Re: Dash-8 incorrect takeoff configuration. Daryl <dwalford@westpine.com.au> - 2025-01-25 09:19 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-25 13:17 +0800
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-25 19:34 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-25 16:44 +0800
                Re: Dash-8 incorrect takeoff configuration. Daryl <dwalford@westpine.com.au> - 2025-01-25 22:36 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-25 22:12 +0800
                Re: Dash-8 incorrect takeoff configuration. Daryl <dwalford@westpine.com.au> - 2025-01-26 09:36 +1100
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-26 10:07 +1100
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-26 02:21 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-26 16:29 +0800
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-26 20:14 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-27 12:17 +0800
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-27 19:52 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-27 16:56 +0800
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-28 04:33 +1100
                Re: Dash-8 incorrect takeoff configuration. Sylvia Else <sylvia@email.invalid> - 2025-01-28 11:52 +0800
                Re: Dash-8 incorrect takeoff configuration. "Rod Speed" <rod.speed.aaa@gmail.com> - 2025-01-28 15:57 +1100

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