What Is a Visual Descent Point (VDP)? How to Find It, Calculate It and Fly It

A visual descent point (VDP) is a fixed point on the final approach course of a nonprecision straight-in approach. It marks where a stabilized visual descent from the minimum descent altitude (MDA) to the runway can begin. On the approach chart it is the bold V in the profile view.

The FAA’s guidance is short: the pilot should not descend below the MDA before reaching the VDP. The VDP is still advice, not a legal decision point. The missed approach point (MAP) is where the regulations force a decision.

When no VDP is published, pilots estimate one with a rule of thumb: divide the MDA’s height above touchdown (HAT) by 300. The answer is the distance from the runway, in nautical miles, where a roughly 3-degree descent begins.

What a VDP Is, According to the FAA

The Aeronautical Information Manual (AIM 5-4-5) defines the VDP as a defined point on the final approach course of a nonprecision straight-in approach. From it, a stabilized visual descent from the MDA to the runway touchdown point may be commenced.

It is identified by DME or by RNAV along-track distance to the MAP. Its distance is based on the lowest MDA published on the approach.

The VDP is also tied to a descent angle. It is harmonized with the angle of the runway’s visual glide slope indicator, such as PAPI lights, when one is installed, or with the procedure’s vertical descent angle when there is none.

That is the whole point of it. Leave the MDA at the VDP and the descent to the runway matches the glide path of the runway’s visual glide slope indicator, where one is installed.

How to Find the VDP on an Approach Chart

Look in the profile view, the side-on drawing of the final approach. The VDP is the bold V on the final approach course in the profile view, usually with a distance from the runway or a DME value beside it.

On RNAV (GPS) approaches, the AIM says a VDP will be published on most procedures. It applies only to aircraft flying the LP or LNAV minimums, not LPV or LNAV/VNAV, which have their own vertical guidance down to a decision altitude.

The chart above shows both details. The V sits 1.3 NM from Runway 23, and the asterisk note limits it to LNAV only.

If your aircraft cannot identify the VDP, for example a VOR approach whose VDP is defined by DME flown without DME, the AIM is clear: fly the approach as though no VDP had been provided.

How to Calculate a VDP When None Is Published

The standard rule of thumb takes three steps:

1. Find the height above touchdown (HAT) for the MDA you are using. It is printed in the minimums box beside the MDA.
2. Divide the HAT by 300. The answer is the VDP’s distance from the runway threshold, in nautical miles.
3. Turn that into something you can fly: add it to, or subtract it from, the DME reading at the threshold, or count back along the RNAV distances to the runway.

Boldmethod’s worked example uses the Crookston, Minnesota (KCKN) VOR/DME approach to Runway 13, where the lowest MDA sits 344 feet above the touchdown zone. Divide 344 by 300 and the VDP is about 1.15 NM from the runway.

That figure is a distance from the runway, not a DME reading. DME measures distance to the station, so you still have to add or subtract to find where 1.15 NM falls on your DME.

Why the magic number is 300

A 3-degree path loses about 318 feet for every nautical mile flown. That is the tangent of 3 degrees multiplied by the 6,076 feet in a nautical mile.

Dividing by 300 instead of 318 is easier in your head and puts the VDP slightly farther out. For the KCKN example, the exact 3-degree answer is about 1.08 NM, against 1.15 NM from the rule of thumb.

A homemade VDP is an estimate. A published one is based on the procedure’s lowest MDA and matched to the runway’s visual glide slope indicator, or to the VDA where there is none, so always use the charted V when there is one.

The descent rate you need from the VDP

Finding the point is half the job. You also need a descent rate that holds roughly 3 degrees at your groundspeed: 318 feet per nautical mile, multiplied by groundspeed in knots, divided by 60.

The AIM points pilots to the rate of descent table in the back of the U.S. Terminal Procedures Publication for the same job. Set that rate on the vertical speed indicator at the VDP to help hold a stabilized descent to the runway.

Why Some Approaches Have No VDP

The AIM gives three examples of why a VDP may not be published: an obstacle penetrates the visual surface between the MDA and the runway threshold, the approach lacks distance-measuring capability, or the procedure’s design prevents a VDP from being identified.

The first reason matters most. A missing V can be a warning that something sits under the path you would naturally fly from the MDA.

Some charts are more explicit. When an obstacle would force a pilot off the descent angle between the MDA and touchdown, the FAA replaces the published VDA with the note “Visual Segment- Obstacles” in the profile view.

So if you calculate your own VDP on one of these approaches, treat it with care. Before leaving the MDA, make sure the visibility lets you see not only the runway but anything in your way.

Can You Descend Below the MDA Before the VDP?

The regulation itself never mentions the VDP. 14 CFR 91.175(c) lets you go below the MDA, outside enhanced flight vision (EFVS) operations, only when all three of these are true:

• The aircraft is continuously in a position from which it can descend to a landing on the intended runway at a normal rate of descent, using normal maneuvers.
• The flight visibility is not less than the visibility the approach requires.
• At least one of the listed visual references for the runway is distinctly visible and identifiable: the approach lights, the threshold or its markings or lights, the runway end identifier lights, the visual glideslope indicator, the touchdown zone or its markings or lights, or the runway, its markings or its lights.

There is one extra limit on the approach lights. Using them alone, you may not descend below 100 feet above the touchdown zone elevation unless the red terminating bars or red side row bars are also in sight.

The VDP comes from the AIM, which says the pilot should not descend below the MDA before reaching it. Leave the MDA early and you are below a normal glide path, close to the ground, in exactly the place the VDP is there to keep you out of.

The two rules work together. Meeting the 91.175 conditions makes the descent legal, and leaving at the VDP makes it the planned, stabilized one.

What Happens If You Pass the VDP Without the Runway in Sight

No regulation forces a missed approach at the VDP. You may stay level at the MDA and continue to the MAP, and you can still descend if the 91.175 conditions are met before you get there.

The catch is geometry. Every second you stay level past the VDP, the descent left to the runway gets steeper, as the diagram above shows.

The AIM warns that descent below the MDA between the VDP and the MAP may be inadvisable or impossible. Aircraft speed, height above the runway, descent rate, the amount of turn and runway length are among the factors the pilot must weigh to decide whether a safe landing can still be made.

That is why many pilots plan to go missed if the runway environment is not in sight by the VDP, as Boldmethod notes. The faster the airplane, the higher the descent rate needed for the same angle, so the option shrinks quickly in a jet.

At the MAP, the choice is gone. Under 91.175(e), if the conditions for going below the MDA are not met on arrival at the missed approach point, or at any time below the MDA, the pilot must immediately execute a missed approach.

Which Approaches Have a VDP

VDPs belong to nonprecision straight-in approaches: the ones flown down to an MDA rather than a decision altitude. The AIM defines a nonprecision approach as one with course guidance but no glidepath guidance, such as a VOR, NDB or LNAV approach.

A localizer-only approach fits the same pattern. It gives left and right guidance to the runway but no glide slope, so it is flown to an MDA too.

Precision approaches such as the ILS, and approaches with vertical guidance such as LPV and LNAV/VNAV, do not use a VDP: it never applies to ILS, LPV or LNAV/VNAV minimums. They give glidepath guidance down to a decision altitude, so there is no MDA to leave.

Where a combined ILS or LOC chart shows a V, it is for the localizer minimums.

VDP vs VDA: Two Tools for One Problem

The vertical descent angle is the VDP’s partner. FAA policy is to publish a VDA on all nonprecision approaches, except those published with vertically guided minimums (such as ILS or LOC charts) or no-FAF procedures without a step-down fix.

The VDA is charted in the profile view after the fix it is computed from, with the threshold crossing height it aims for. It helps a pilot fly one continuous, stabilized descent on final rather than diving to the MDA early and flying level.

The AIM is firm that the VDA is advisory only. It is not vertical guidance derived from the procedure, and it does not guarantee obstacle protection below the MDA in the visual segment.

Whichever you use, the visual references still decide it. A VDA or a VDP tells you where a normal descent would be, and only meeting the 91.175 visual requirements lets you take it.