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Hot temp platform approach

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Old 15th Sep 2014, 01:01
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Hot temp platform approach

Hello,

I like to calculate mi NPA profile to correct for hot OAT just like i do in cold weather, this changes the indicated altitude over the FAF to read below published, how legal is this?, I'm sure many instructors wont like it.
What i do to avoid this is to change the flight path angle by .2 degrees or so, though id like to stick to the 3 deg.

I'd appreciate inputs, thanks
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Old 15th Sep 2014, 05:53
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In hot condition you will be higher on the approach and therefore on the 'safe side'. There is no need to correct for been high. Just be aware that on steeper than normal approaches (3.2deg or greater), in hot conditions, for might find it difficult to stabilise your speed due high approach angle.
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Old 15th Sep 2014, 06:23
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QED

Excellent answer. Simple and correct.
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Old 15th Sep 2014, 12:35
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"What i do to avoid this is to change the flight path angle by .2 degrees or so, though id like to stick to the 3 deg."


Why?
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Old 15th Sep 2014, 14:15
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If you don't correct for hot weather you'll be above glide path on the entire approach, thats why i do it.
im just doing the same thing an ILS glide slope does, if you have noticed in hot weather you will cross the FAF on the GS at a lower indicated altitude.
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Old 15th Sep 2014, 14:23
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John Smith, does invention require you to come up with something new?
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Old 15th Sep 2014, 14:57
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hello DOT I fly for Qatar Airways and I use an application called airports with an approach path calculator, you dial in the initial approach altitude, the runway elevation, descent angle and temperature. works great in the 50 degree weather of Doha, but I also used it in Kathmandu and Sanaa before use start RNP AR.
tell me this is lack of airmanship.
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Old 15th Sep 2014, 17:55
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Well very nice that you are interested in new additions for the betterment but, you need to get the procedures approved before you actually use it. You can't just follow your brain waves.

Take my advise, delete your posts before Qataris find out your E=mc2 formula.
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Old 15th Sep 2014, 18:28
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The formula is right there, in Doc 8168. When the temps are extreme, I do those calculations as well. Being 400 ft above on a 6 mile NPA has its meaning. But only for awerness, no change to FCU settings. I do call this airmanship.
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Old 15th Sep 2014, 18:35
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Just fly the goshdarn airplane, this isn't rocket science, really. 3.0deg and 3.2 is close enough for guvmint work.
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Old 15th Sep 2014, 18:43
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As you dont change actual altitudes,you can always brief your increased TAS due to temperature and brief expected descent rate,your instructor will be happier.
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Old 15th Sep 2014, 20:14
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I love rocket science, and sometimes I feel ashamed of saying I'm a pilot thanks to the level of mediocrety I see.
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Old 15th Sep 2014, 22:29
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So you are cleared to 3000 in readiness for an ILS approach.

It's isa +30.

Are you seriously saying you'd level out at 2640'. ?

ATC might have something to say as well...
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Old 15th Sep 2014, 22:40
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I love rocket science, and sometimes I feel ashamed of saying I'm a pilot thanks to the level of mediocrety I see.
The mediocrity in this thread is unfortunately displayed by yourself.
Agreed as per previous commentators, you DO NOT change procedures which are created to keep you safe from terrain.
Being a bit too high on such approaches due to (very) high temperatures is safer than being too low making an incorrect correction for it.
There is indeed documentation on the HOW to do such thing, they are meant for procedure designers, not pilots personal use to correct established, approved and authorised approach procedures.

However, I can see you strongly feel about this.
So why won't you submit this change of procedure in a formal proposal to relevant authorities?
Maybe, just maybe, if reasoned properly, changes to established procedures when confronted with extremely hot conditions as described, could be made available to all other aviators. But these changes need to be thoroughly examined, documented and ratified prior to use, which is where the authorities would need to come in.
Rather than fly these procedures now already, put your efforts into a formal proposal for improvement to the authorities.

Until then, please don't change the altitudes and angles of procedures which were designed to keep (all of) us safely away from ground. Remember, CFIT was not too long ago the main reason for deaths in aviation.
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Old 15th Sep 2014, 23:01
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As long as you are under radar control, under NO CIRCUMSTANCES shall you correct on your own for temperature!
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Old 16th Sep 2014, 03:33
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Let's take it this way. God forbid you face an incident, even if it's not your fault, you will definitely be questioned about your HUMIDITY COMPENSATION LAW. Prepare yourself for that then.
Btw is it a single pilot operation? What's the other guy doing when you are experimenting?
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Old 16th Sep 2014, 06:38
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Some of the above comments have the only objective of creating a conflict and raising the stress level of this simple discussion. People are entitled to ask questions and you are entitled to your answers. The aim of a professional forum is to provide constructive answers and to avoid generating a never ending argument out of nothing. The user asked about the legality of his thoughts and asked for inputs as well, doesn't look like a big deal does it ?
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Old 16th Sep 2014, 06:42
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RNP-AR

The CAA better not know that you are using unapproved methods of calculating approach information, especially that of RNP-AR. The data being presented was developed through Airbus and flown by the airline, airbus and the CAA. Warning Flags!
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Old 16th Sep 2014, 10:23
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Asian pilots seem to have a habit of flying low approaches
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Old 16th Sep 2014, 11:45
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B737900ER

That one is uncalled for, let's get back to the topic mate.
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