Survey: Visual Descent Point

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Giannipilota
Posts: 6
Joined: 04 Nov 2021, 18:30

Survey: Visual Descent Point

Post by Giannipilota »

Dear Colleagues,
I am a Retired Airline Captain, who's doing a study on the use of the Visual Descent Point.
I kindly ask you to participate in an anonymous survey that I uploaded in "Google Forms".

With the first click you go to https://goo.gl/forms/VDIP3lhvACpO4btz1

With the second click you can choose the answer you think is correct.
The scenario is as follows: you are on your company's aircraft, in a NPA ( non-precision approach ). When you arrive at the VDP, your visibility allows you to see the terrain, but not the approach lights or the Runway.

With the third click you can respond to the same question, but in a different scenario: you are on a sport aircraft, either owned or rented, and your free choice is not subject to your company's procedures.

With the fourth click (on the coloured button at the bottom left), you submit your answers.

It will only take a few minutes, but your answers will be very useful for this in-depth study.

Thank you for your cooperation.

Giannipilota
Posts: 6
Joined: 04 Nov 2021, 18:30

Re: Survey: Visual Descent Point

Post by Giannipilota »

Thanks to all those who response to surveys; I hope that other pilots kindly want to participate.
Ciao

Giannipilota
Posts: 6
Joined: 04 Nov 2021, 18:30

Re: Survey: Visual Descent Point

Post by Giannipilota »

A good number of readers have already taken part in the survey.
I would like to thank these first participants and invite others to follow their example.
The higher the number of answers, the more precise the results will be.
It is a study that I find interesting and useful; I'll be waiting.
Thanks.
Gianni.

Bracebrace
Posts: 273
Joined: 04 Apr 2006, 00:00

Re: Survey: Visual Descent Point

Post by Bracebrace »

In all honesty, I don't know if I understand the survey. It seems to "general"...? Can you be more specific?

If I understand correctly, this VDP you are referring to old NPA procedures with stepdowns. The majority of airlines use FMS systems that provide some kind of calculated vertical guidance, that will - even in the case of stepdown procedures... wherever they may still exist... - create a managed descent for you.

Giannipilota
Posts: 6
Joined: 04 Nov 2021, 18:30

Re: Survey: Visual Descent Point

Post by Giannipilota »

Dear Bracebrace,
my study intends to deepen the behaviour of pilots around the world during the Non-Precision procedures.
There are still many in the world (LOC, VOR, VOR-DME, NDB, RNAV only lateral, etc.).
Not all planes have FMS.
The Visual Descent Point is the point, along the slope, at the time of reaching (or if you prefer crossing) the MDA.
In my scenario I try to quantify the choices of the operations performed by the pilots in case visibility allows to see only the ground.
To date, with different percentages, all the answers have been chosen.
I have not only made my request on this forum, but in several others and in magazines, so that I can reach as many readers as possible.
I may have made a mistake in choosing Civil Aviation/ General Aviation, but I thought it was the best one available. In case you suggest which sector is more appropriate in your forum.
Ciao, and thank you for your intervention
Gianni.

ManoelAka
Posts: 2
Joined: 14 Dec 2021, 13:49

Re: Survey: Visual Descent Point

Post by ManoelAka »

I will take my time to answer this questionnaire properly. I think that this way, many people will avoid making mistakes to solo trip, as it was my case.

Giannipilota
Posts: 6
Joined: 04 Nov 2021, 18:30

Re: Survey: Visual Descent Point

Post by Giannipilota »

First of all, I would like to thank the colleagues who participated in the survey and sent hundreds useful feedbacks.

The results reported in the chart (updated until today, with some responses still on the way), confirm that it was a good decision to set up my studies on the current procedures related to VDP.
The chart shows that for both, airlines and private/recreational/sport flights, all available procedures are somewhat used.
Depending on the kind of flight, the procedure adopted for the VDP changes: for instance, Pilots working for a Company comply with procedures given by the Company, while in a private flight the Pilot is more free to decide how to proceed.
I think the reason behind these different scenarios is that the Pilots are coached but not properly schooled/trained.
For airlines flights, Pilots comply with the SOP and Manuals’ instructions, but they don’t seem to have understood (or it might be they have not been fully explained) the reasons behind those instructions (why they have to proceed in a way and not in another).
In other writings, I reported 2 examples of school that are not teaching the correct procedure. One of them added on its website a wrong formula, and, although 3 readers suggested to correct it, nothing has been done so far.

Looking forward to reading your comments!
Kind regards
Table eng.JPG

Bracebrace
Posts: 273
Joined: 04 Apr 2006, 00:00

Re: Survey: Visual Descent Point

Post by Bracebrace »

Before any comments are made, could you first then - according to you - explain what is the correct procedure?

NPA procedures depend on 2D or 3D approach, where from a procedural point of view we will also refer to DA (yet you mention MDA?) as they are CDFA based. Pure MDA is only used for ie circle-to-land. So the only reason why VDP would have any kind of meaning is in a circle-to-land. But something tells me this isn't really what you are referring to... you seem to be referring to old school NPA with MDA. That means non-CDFA. No airline does that anymore.

Poiu
Posts: 897
Joined: 14 Nov 2015, 09:38

Re: Survey: Visual Descent Point

Post by Poiu »

Bracebrace wrote: 17 Dec 2021, 13:53 Before any comments are made, could you first then - according to you - explain what is the correct procedure?

NPA procedures depend on 2D or 3D approach, where from a procedural point of view we will also refer to DA (yet you mention MDA?) as they are CDFA based. Pure MDA is only used for ie circle-to-land. So the only reason why VDP would have any kind of meaning is in a circle-to-land. But something tells me this isn't really what you are referring to... you seem to be referring to old school NPA with MDA. That means non-CDFA. No airline does that anymore.
Not many, but there still are operators who do use the dive and drive technique when flying NPAs.
When you fly, eg, a VOR approach you treat the MDA as a DA, but it remains a MDA.

As for the correct answer, this is what EASA says:
Missed Approach - The manoeuvre associated with the vertical profile of the missed approach should be initiated not later than reaching the MAPt or the DA(H) specified for the approach, whichever occurs first. The lateral part of the missed approach procedure must be flown via the MAPt unless otherwise stated on the approach chart.
In case the CDFA technique is not used the approach should be flown to an altitude/height at or above the MDA(H) where a level flight segment at or above MDA(H) may be flown to the MAPt.

Giannipilota
Posts: 6
Joined: 04 Nov 2021, 18:30

Re: Survey: Visual Descent Point

Post by Giannipilota »

Dear Poiu,
thank you for your intervention.
It is the exact spirit of my study, deepen this topic that does not seem to be clear, just see the percentages of the answers and the writings on the forum.

Giannipilota

Austin38
Posts: 3
Joined: 17 May 2023, 08:29
Contact:

Re: Survey: Visual Descent Point

Post by Austin38 »

Giannipilota wrote: 19 Dec 2021, 09:41 Dear Poiu,
thank you for your intervention.
It is the exact spirit of my study, deepen this topic that does not seem to be clear, just see the percentages of the answers and the writings on the forum.

Giannipilota
I'm glad my intervention aligns with the purpose of your study. The unclear nature of the topic is evident from the varied percentages of answers and forum discussions. Good luck!

harsada
Posts: 1
Joined: 18 Feb 2024, 19:46

Re: Survey: Visual Descent Point

Post by harsada »

Thank you for your intervention. It aligns perfectly with the essence of my study, which aims to delve into a topic that appears to lack clarity. I intend to examine the percentages of responses and the discussions within the forum to gain deeper insights. fm whatsapp

Diamondd
Posts: 1
Joined: 13 May 2024, 11:48

Re: Survey: Visual Descent Point

Post by Diamondd »

Thank you for sharing this important survey on
the use of the Visual Descent Point (VDP) during non-precision approaches
. As an experienced retired airline captain, your study on this topic is valuable.

I'm happy to participate in the anonymous survey and provide my insights. The scenarios you've outlined, including the differences between commercial airline operations and personal/recreational flying, will provide helpful context.
Good luck to you :!: quordle

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