NDB-B and NDB-C

[xdashdriver]

VOR-A doesn't mean it's 30 degrees off. It means it does not meet straight-in criteria and therefore you have to circle to land. When there's more than one non-straight in procedure, then they name them B and C etc. Nothing more to it than that.

Ray

 

[flyer172r]

If there's no -A for your airport, there may be a -A to another airport listed under the same city. That's the way it used to be in our town when we had two airports. There was a VOR-A to one airport, a VOR-C to the other. I think the lettering goes by commissioning order, and it doesn't necessarily mean it's 30 degrees off, anything more than 30 doesn't mean straight-in criteria.

 

[pilotjc]

AIM 5-4-19d Cirlcing Approach

d. Straight-in Minimums are shown on the IAP when the final approach course is within 30 degrees of the runway alignment (15 degrees for GPS IAPs) and a normal descent can be made from the IFR altitude shown on the IAP to the runway surface. When either the normal rate of descent or the runway alignment factor of 30 degrees (15 degrees for GPS IAPs) is exceeded, a straight-in minimum is not published and a circling minimum applies. The fact that a straight-in minimum is not published does not preclude pilots from landing straight-in if they have the active runway in sight and have sufficient time to make a normal approach for landing. Under such conditions and when ATC has cleared them for landing on that runway, pilots are not expected to circle even though only circling minimums are published. If they desire to circle, they should advise ATC.
​

 

[A Squared]

Hmmm.I always thought that the "alpha" designation at the end of an approach referred to the fact that it is 30 degress or more of the extended centerline of the runway.

Well, yes, partly, Or more completely as several have already correctly stated, it desn't meet straight in approach criteria.

That could mean that the final approach course is more than 30 degrees from the runway centerline, *or* the final approach could be lined up with the runway, but the MDA will not allow a normal descent and landing. I know of a number of "circiling" approaches like this: final approach course lines you right up with the runway, but the MDA leaves you too high .... so it can't be considered a "straight in" approach.

Here's the naming rules:

If it's it meets straight in criteria, it will have the navaid and the runway in the title i.e. VOR RWY24.

If it does *not* meet straight in criteria (either because of alignment or descent) it will have no runway and a letter near from begining of the alphabet i.e: VOR-C

If it meets straight in criteria and there is another, different, straight in approach of the same type to the same runway, it will have both the runway and a letter from the end of the alphabet i.e.: ILS-Z RWY 27 and ILS-Y Rwy 27
note: at one time the TERPS specified numbers to be used in this situation so you may still encounter approaches with numbers in the titles i.e. ILS-2 Rwy 33


Does that help?