What is a PDP?

[Steveair]

Does anyone know what a PDP is? I've heard guesses that it's a Precission Descent Point but I need a definate, 100% no doubt answer. If it is that, would the PDP just be GS intercept? Is it depicted anywhere?

 

[AlwaysLearning]

Could it be VDP? Visual Descent Point? Ive been out of instructing a while so PDP could be new term!?

 

[FarginDooshbahg]

How about Pilot Descent Point? It's like a VDP only not charted, but instead calculated by the pilots to be used like a VDP on a non-precision approach.

 

[Steveair]

How about Pilot Descent Point? It's like a VDP only not charted, but instead calculated by the pilots to be used like a VDP on a non-precision approach.

By George, I think he's got it...

 

[firstthird]

I've always heard it called a Planned Descent Point.

A technique where the pilot caculates a VDP based on a 3 degree descent from MDA to the TDZ. The idea is that if you see the runway at that point, good deal, descend and land. If you do not, you execute a missed approach since it isn't necessarily safe/comfortable to do a let down to landing from the actual MAP on many approaches (think VOR at the field and station passage is MAP).

 

[Steveair]

I've always heard it called a Planned Descent Point.

A technique where the pilot caculates a VDP based on a 3 degree descent from MDA to the TDZ. The idea is that if you see the runway at that point, good deal, descend and land. If you do not, you execute a missed approach since it isn't necessarily safe/comfortable to do a let down to landing from the actual MAP on many approaches (think VOR at the field and station passage is MAP).

Thanks for your time & help!

 

[Guitar Guy]

To calculate a PDP, you can take your MDH and divide it by 300. That will give you the distance from the runway at which to descend in order to maintain a 3-degree glideslope. This is handy if you have a DME that measures either up to or back from the threshold. For example, if your MDH is 450 ft AGL, your PDP is 1.5 NM (450/300) from the runway threshold.

Another, less accurate way to calculate a PDP/VDP is to take your time to the MAP and subtract 10% of the MDH. For example, if the time to the MAP is 2:57 and the MDH is 450 ft AGL, the time to the PDP is 2:12 (2:57 - 10% of 450, which is 45).

I hope this helps a little bit.

 

[Steveair]

That sure did / thanks guitarguy.

 

[potrack]

New terms are funny.

PDP?

I used to just say, "If a VDP isn't published...calculate your own"

Then I would ask the student, "Did you figure out a VDP?"

Funny how the one that you calculate yourself has a different name?

Next thing you know, they will say that a 'TOD' is derived from an FMS VNAV solution. If you figure out when to start your enroute descent yourself.....you have to call it something else.

 

[FarginDooshbahg]

I've always heard it called a Planned Descent Point.

Ooops. Yea, that's what I meant to say. Planned Descent Point. But the explanation remains the same.