Here is the AIM's definition for a clearance limit:

CLEARANCE LIMIT− The fix, point, or location to which an aircraft is cleared when issued an air traffic clearance

Assume a clearance such as: "Cleared to Los Angeles Internal Airport (KLAX) via..."

This means our clearance limit is KLAX.

But what does this mean if I follow the instructions in 91.185?

If the clearance limit is not a fix from which an approach begins [it's not], leave the clearance limit at the expect-further-clearance time if one has been received [it hasn't], or if none has been received, upon arrival over the clearance limit

A pilot should fly until the last fix on the route and then direct to their clearance limit: KLAX at their last assigned altitude (let's assume FL280).

and proceed to a fix from which an approach begins

Now fly direct from KLAX, with no assigned route, to an Initial Approach Fix (CRCUS or SEAVU).

commence descent or descent and approach as close as possible to the estimated time of arrival as calculated from the filed or amended (with ATC) estimated time en route

Hold at SEAVU or CRCUS (for which there is no published hold--so they can make one up), UNTIL their ETA into LAX. Then, descend in the hold and fly the approach. Or, realizing these fixes are 35nm away from KLAX, would a pilot turn around half way between SEAVU and KLAX to return to SEAVU at their ETA to descend?

Is that crazy to anyone else? To follow this regulation, a pilot would fly over their destination airport and then return to an IAF to do an approach. Does ATC really want us to do this in a lost comm situation? At a minimum, this doesn't seem like a prudent use of fuel which brings safety of flight into the mix.

When and where can I legally start an approach in this scenario?

  • $\begingroup$ I edited your question a bit to (hopefully!) make it more specific and less likely to generate discussion; that's how this site is intended to work best. If I changed it too much then of course feel free to roll back or edit again. BTW, please use the quote formatting for quotes to help screen readers and other software work better. $\endgroup$ – Pondlife Dec 1 '20 at 5:07
  • $\begingroup$ I like it. Good work! $\endgroup$ – Java Addict Dec 1 '20 at 5:11

Note: this may be a dupe of this question. However, you seem to be saying that you've read and understood the regulations on what to do, you just don't believe that ATC or the FAA really expects you to follow them.

In the scenario you describe you are indeed expected to fly from the airport to an IAF before beginning an approach. There's a long and detailed article in IFR Magazine about clearance limits, which discusses the regulations and the practical options. It makes a similar point to yours about lost comms:

Since the clearance limit is the destination airport, very few approaches start there. An airport is never used as a fix in IFR. A fix is an intersection, waypoint or NAVAID. Moreover, receiving an EFC time in advance is simply silly. This would also presume the issuance of holding instructions. Why would a controller issue these things since lost communication cannot be predicted?

It also acknowledges that many pilots share your opinion on the lost comms action:

Many pilots disdain these rules as onerous, unnecessarily time-consuming and complex.

The article then notes that there have been multiple attempts to change the FAA's mind:

Since 2009, there have been about five challenges to this rule. In the latest iteration, our past editor, Jeff Van West, wrote the Office of Chief Counsel in late 2017, arguing that 91.185 (c)(3)(ii) is inconsistent with current air traffic practices and creates an unnecessary hazard.

But, you can read that 2017 legal interpretation yourself and you'll see that the FAA really does expect pilots to follow the regulation as written:

As you correctly state in your letter, the requirements of § 91.185(c)(3)(ii) are rarely in effect thanks to the improved technology ensuring that communications between pilot and ATC are not lost. However, the requirements of (c)(3)(ii) are necessary to ensure the safety of the NAS when a pilot is unable to communicate with ATC.
we affirm our previous interpretations of § 91.185(c)(3).

So that's the official answer for now (unless I missed a more recent interpretation).

Finally, if you want an alternative course of action, IFR Magazine's suggestion is to fly from the airport to an IAF and then invoke emergency authority to start a descent immediately, without holding:

ATC does not want you flying a holding pattern while it’s diverting traffic everywhere to avoid a conflict. You have unintentionally shut the airport down. When you reach an IAF of your choosing, ATC will know which approach you intend to use. At the IAF, use your emergency authority and begin descent.

That complies with the regulation and although it burns more fuel your priority should be acting predictably and landing safely. An IFR reserve should be plenty to allow for the extra flying time: KLAX to SEAVU is about 45NM, which isn't much time at jet speeds.

  • $\begingroup$ I had read an article on this years ago; but I've been scouring the Internet, and I couldn't find it. Thank you for the great response! I looked at the answer you referenced, and it seemed to gloss over these finer-point-details which you eloquently covered. $\endgroup$ – Java Addict Dec 1 '20 at 5:54
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    $\begingroup$ The main takeaway is that ATC with a comms failure will expect you to take the most logical and sensible path and take action (clearing traffic) based on that expectation. $\endgroup$ – John K Dec 1 '20 at 15:58

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