This question refers to US Air Carrier procedures for determining takeoff minimums, as published in FAR 91.175, 121.651, Carrier OpSpecs, and the US Terminal Procedures Publication booklet.

As nicely answered in this question, we know that low-visibility minimums for takeoff are outlined in a carrier's opspecs, with paragraph C078 granting approval for "lower than standard" visibility requirements, if the airport runway doesn't already have published higher than standard takeoff minimums.

An airport with a published higher-than-standard minimum for one or more runways is indicated on approach charts with the upside-down triangle with the letter T inside (although this may also indicated only an obstacle departure procedure, or both an ODP and a minimum). The published minimums themselves can be found in the US Terminal Procedures Publication.

My question is about runways marked as "Takeoff Minimum: NA". What does "NA" mean? Does it mean that "lower than standard" minimums may not be used. Or does it mean "all other runways have comments, but no comments are necessary for this runway, so lower-than-standard takeoff minimums published in opspecs are fine and dandy"? There also seems to be different "NA" indications; some with comments such as "obstacle" or "ATC", and some without any comment at all.

I cannot find an answer in the FAA's Instrument Procedures Handbook, the AIM, or elsewhere.

One example is Columbia, CA which has a simple "NA" for runway 35.

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Another example is Cloverdale, CA, and RWY 32 is marked as "NA" but has the comment of "Obstacle".

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A third example is Merrill Field in Anchorage, Alaska, with the comment of "NA - ATC".

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2 Answers 2


On page D1 of the TPP-Abbreviations

NA.......Not Authorized

Sometimes they give the reason why it is not authorized like in your examples. Other times they don’t. In these cases, you can’t use the runway for IFR departures. (non-Part 91)

N/A.......Not Applicable

I don’t recall seeing this terminology in the departure minimums section, so if you could show me where you found it, maybe I could explain it.

  • $\begingroup$ Wow. My dunce moment... I was completely reading those entries as "N-slant-A", as opposed to just "NA". You're right... that terminology ("N/A") does not exist. Thus... I cannot show you where I found it. smh Thanks! $\endgroup$
    – Jimmy
    Commented Apr 2, 2017 at 20:30
  • 1
    $\begingroup$ Yuck - I'd hate to ignore that as a part 91 guy and fly into some granite clouds. $\endgroup$
    – Pugz
    Commented Apr 3, 2017 at 1:07
  • $\begingroup$ I’ve been thinking about that as well. Takeoff minimums don’t apply to Part 91, but does NA? I know that you can’t use an approach that says, NA Alternate Minimums Not authorized, but can you use a departure marked NA? $\endgroup$
    – JScarry
    Commented Apr 3, 2017 at 14:35

NA = Not Authorized, just like in an approach minimum line

The use of "NA" in takeoff minima is identical to that in approach minima -- it means "Not Authorized", or in simpler terms, "you can't use that runway for an IFR takeoff."

The brief remarks explain why that is so:

  • "Obstacles" or "Terrain" mean what they say -- trying to take off from that runway in IFR risks crunchy, smashy sounds.
  • "ATC" means that there's some other traffic flow blocking the takeoff path, or some other reason the runway is unsuitable for an IFR takeoff (such as inadequate lighting)
  • "Airspace" usually occurs because a takeoff from that runway would cause you to infringe on controlled or special-use airspace.
  • "Environmental" could be terrain, obstacles, or some other reason
  • $\begingroup$ Thanks! See my comment on @jscarry's answer. Both answers are perfectly acceptable, but I'll toss "accepted answer" points his way, since he has less. (I assume that's an acceptable community norm) $\endgroup$
    – Jimmy
    Commented Apr 2, 2017 at 20:36

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