Expert: Heiko Hanusch - 9/18/2006

Question
Heiko,

Where did this general rule come from?  I have never heard of it.  Was it ever in print?  It would seem that if it is important enough, and something I could get violated for, then it would be written someplace, like in the FAR.

As far as the special arrangement, how would anybody, like a transient pilot, know of a special arangement unless they called tower ahead of time?

Not to discount your answer, you may very well be correct, but it seems like something this important really ought to be spelled out and not on a case by case basis.  I still feel like this is as clear as mud.

If you can answer these follow up questions, great.  If not, that's ok too.  I really appreciate your time and effort on this.

Scott

I was hoping
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Followup To

Question -


Hi Heiko,

As a flight instructor, I'm betting you could help me with this.

I fly in the San Diego area.  In the north part of San Diego County is an airport called Palomar-McClellan.  It is a Class D with two Class E surface area extensions to help facilitate instrument approaches when the Class D is operating under IFR.  Palomar Tower is under the impression that when they are calling the Class D IMC, that the Class E surface area becomes under their control and they can deny aircraft entry into it.  I have found nothing in the FARs that say that.

On the contrary, in the AIM, I found a section (3-16 (e)(2)) which reads:

Extension to a surface area: "... Such airspace provides controlled airspace to contain standard instrument approach procedures WITHOUT IMPOSING A COMMUNICATIONS REQUIREMENT ON PILOTS OPERATING UNDER VFR."

Often, although the Class D may be IMC, the Class E to the east (further inland and away from the marine layer of clouds) is very much VMC.  Therefore, I was under the impression a VFR pilot wishing to pass through or loiter in that Class E was good to go.

Is there a regulatory section that would forbid a pilot operating under VFR in VMC from doing this?

Thanks Much,

Scott

Answer -
Hello Scott,

Thank you for your question.
As a general rule, if the extension is 2 miles or less then it is controlled by Class D (in your case)tower in IMC conditions. If the extension is more than 2 miles than it is Class E and governed by its rules.
The key here is "general rule". It could be that Palomar Tower has a special arrangement and controls all of the extension. You would have to find out by calling the Tower and get their established rules.
Extensions are decided on a "per case" basis, so it could be that there is a special arrangement for Palomar Class D. If there is not, than you are correct with your assumptions.

I hope this helps any,

H2

Answer
Hi there again,

This rule is actually in print. You can find it in the AIM under Airspace at 3-2-5 (Class D) than (4) (d).


d. Arrival extensions for instrument approach procedures may be Class D or Class E airspace. As a GENERAL RULE, if all extensions are 2 miles or less, they remain part of the Class D surface area. However, if any one extension is greater than 2 miles, then all extensions become Class E.


As for the part you asking how you are supposed to know...
Before every flight the PIC shall become familiar with all information, weather etc. pertinent to his/hers intended route of flight (FAR Part 91, Preflight).

The reason they (the FAA) says "General Rule" is because, as for any rule spelled out in the AIM or FAR's, for that matter, it is always possible to negotiate "special procedures" which are locally negotiated and distributed.

I hope this helps a bit more,

H2