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High energy descents & approaches

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High energy descents & approaches

Old 22nd Mar 2016, 20:45
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High energy descents & approaches

Hello everybody,

I'm currently working on a project for my Master's degree dissertation.
I'm looking to optimize the energy monitoring during descent and approach, my question is simple. In case of a missed approach due to a high energy state (coming in too high and too fast), what are the origins/scenarios leading to a high energy approach.
I've thought about:
-if you are vectored and too high/fast, the distance leading to the runway may be drastically reduced, leading to a high energy state.
-A descent that is initiated too late.

What other scenarios would you suggest?

Thanks

AA757

Last edited by AA757; 22nd Mar 2016 at 21:02.
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Old 22nd Mar 2016, 20:47
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Winds changing with altitude, especially a strong tailwind on approach but calm or light winds down the landing runway, or the typical Canary Island wind shifts (-20 to +20 is not unusual - a 40kt positive shear)
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Old 22nd Mar 2016, 22:18
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* Airspace restrictions, or traffic below you preventing you to descend, are common ones operating into some airports.
* Others include bad planning: Sh!t in [email protected] out rings a bell regarding FMC route, eg magenta line to fly (extra track miles which will not be flown create a higher idle descend profile).
* to name a few
* ATC shortcuts
* terrain considerations

Last edited by Skyjob; 22nd Mar 2016 at 22:32.
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Old 22nd Mar 2016, 22:24
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Maybe you commence the descent at the appropriate point in terms of time and distance, but you weren't assertive enough in your RATE of descent.

....waiting too long to deploy speedbrakes etc.

And/or a speed restriction by approach control. "I can't SLOW down and GO down at the same time."
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Old 23rd Mar 2016, 14:36
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Seems to me a real-time display to ATC of total energy (i.e. kinetic + potential) vs. distance remaining would give the groundbound controller an appreciation of the problem, helping him to avoid impossible "guidance" to the PF.
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Old 23rd Mar 2016, 15:00
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Well,when i tell them "unable",they normally get the message.
If too high,get in the hold,descend while zipping coffee,if short cuts are standard,remember for next time and start your descent early.
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Old 24th Mar 2016, 03:37
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A get-out-of-jail-free card .. certainly not an efficiency bonus, though .. if held ridiculously high, pitch up with boards .. gear down .. dirty up (below max flap level) .. and then go down at gear limit .. subsequently approaching the appropriate flap limit speed.


Good for bringing the 737 back to better than a mile a thousand and got me out of trouble on a couple of occasions in years gone by coming into Sydney with traffic problems keeping us very high initially.
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Old 24th Mar 2016, 15:16
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More efficient than loading the flaps,screwing it up and having to go around
Safety first,pax comfort second,fuel saving last.
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Old 24th Mar 2016, 23:55
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ICING for the list of reasons of to fast and to high.

When you get into icing on the jet anti-ice system need more power so flight idle increases. As a result aircraft has more power which is not desired on descent... Such thing can drastically change descent profile on E195.
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Old 25th Mar 2016, 04:33
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.. presuming that the pilot is monitoring and controlling the descent .. one does something about any profile consideration early enough to prevent the nuisance turning into a problem ... the pilot has to fly the plane .. not the other way about.
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