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Non-precision approaches and Papi

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Non-precision approaches and Papi

Old 13th May 2013, 19:03
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Non-precision approaches and Papi

I often operate into an airfield that has a non-precision approach onto the landing runway. The approach used to have a descent gradient of 3degrees to just under three miles and then a steeper approach to the runway. Under Eu-ops this has been changed to a continuous 3.34 degrees continuous descent.The problem however is that the airport has a displaced threshold and the Papis are set to 2.73 degrees. Under the old system the transition from the approach to the papis would have been easier but now at MDA you would will invariably be looking at four whites. The threshold is displaced to protect the localizer antenna for the other runway but the localizer hasn't been servicable for almost ten years.Additionally the papis are sited only 450 feet from the displaced threshold and ths do not give the MEHT for a large aircraft.
The set up onto this runway is not helped by the fact that the majority of the bulbs in the papi installation are unservicable, and only a few of the lights are visible in daylight hours.
Is there any legislation that could be used to complain to the airport management company about the unsuitability of the current set up?

Last edited by tubby linton; 13th May 2013 at 19:12.
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Old 13th May 2013, 19:21
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However, PAPI's aren't a requirement as far as I'm concerned, aren't included as part of my operators stable criteria and are only there as guidance.

The only way I think you'll get the Airport Authority to listen is to withdraw flights there until the problems you bring up are addressed. Obviously that is a situation for your management to talk about and possibly get other operators involved too.
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Old 13th May 2013, 19:33
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The trouble with this airfield is twofold. Firstly if you fly a purely visual approach with the location of the papi you will not achieve MEHT as you cross the displaced threshold. This is not a great problem as the undershoot is obstacle free but you will still land short of the intended spot. The second is if you were to fly this approach in anger. If you descended to MDA and saw four whites on the papi would you try and achieve the correct papi path or would you ignore it?
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Old 13th May 2013, 19:38
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From what I have read here, and assuming the respective field is in the UK, this might be a case for a CHIRP report.

Edit: Reading the original post again, I must say this doesn't sound like the field was in the UK.

Last edited by hvogt; 13th May 2013 at 19:43.
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Old 13th May 2013, 19:53
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It wasn't . UK airfield are covered by CAP 168 which would not allow this situation.
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Old 13th May 2013, 20:01
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It would be best if you disclosed the airport in question...answers would be much better...

has it been this way for 10 years?

Last edited by FlightPathOBN; 13th May 2013 at 20:02.
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Old 13th May 2013, 22:35
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Interesting case.. and JAR-OPS...

The PAPI system primary function is to assist visual glide slope guidance in non-precision approaches environment.

The PAPI at 2.73 shown on the AIP, is not coincident with the GPA of 3.34 shown on the plate, but is not reflected on the plate as a situational awareness warning.

With the increased GPA and MDA, the procedure design on the plate is certainly aware of the obstacle, (which actually may be an AAO (Assumed Adverse Obstacle for the over water approach, rather than the ILS for the other runway)
The PAPI system should be re-aligned accordingly. (unless you are baro-vnav and it is -30 C degrees out )
In the meanwhile, the plate should reflect the message that "PAPI and GPA are not coincident."

At least you are in the white.

Last edited by FlightPathOBN; 13th May 2013 at 22:38.
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