No Shortcut Here

Air Safety Link, June/July 2000

By Capt. Wally Roberts (TWA, Ret.)

The FAA recently received a discrepancy report from a major airline that flies into Jackson Hole, Wyo. (JAC). The carrier’s complaint concerned the difficulty its flight crews were having turning inbound on the localizer course via the Dunoir (DNW) VOR’s feeder route.

The pilots and the carrier’s flight operations management thought the procedure permitted a "NoPT" turn inbound on the localizer at the point where the DNW 267-degree radial intercepts the localizer course (QUIRT fix). The complaint focused on what the airline saw as a deficient approach procedure, because the feeder route required maintaining an altitude of 12,000 feet until the QUIRT fix. The airline said this put its flights above the glideslope, making the approach difficult to fly from QUIRT inbound.

What everyone at the airline was missing was the lack of a "NoPT" authorization on the DNW-QUIRT feeder route. The procedure was designed with the requirement to make the procedure turn (PT) from over QUIRT or from the feeder route to the south from over JAC VOR.

Pilots in the United States are so used to being vectored to final that they often overlook the concepts and requirements of the full approach. A lot of this can be attributed to "canned" training at the airlines and the lack of comprehensible guidance from the FAA. Further, as more of us fly to more international destinations, we learn non-U.S. rules, which have subtle differences.

The ATC system in this country is designed to keep the metal moving. But at such locations as Jackson Hole, with its potentially deadly terrain all around and with its lack of terminal ATC radar coverage, the concept shifts from "moving metal" to "y’all be careful out there."

What we do see in FAR 91.175 (j) are rules about when you must not make a procedure turn—(1) when vectored to final, (2) when arriving via a route that is designated NoPT, and (3) when timed approaches are being conducted from a holding pattern at the FAF or intermediate fix. A recent change to the AIM (Para. 5-4-8) goes on to state that a PT is required on any approach that has a PT, except for only those three exceptions. And a holding pattern that is shown in the plan view in bold printer’s type, and in the profile view as well, is the equivalent of a PT, albeit with less airspace available to make the course reversal.

Did the FAA do the best possible design job with the Jackson Hole ILS? No. The procedural data Note No. 1 about how to hang the radios before making the procedure turn makes no sense at all. Also, pilots can easily overlook the fact that the route from JAC VOR to QUIRT is based on the 004-degree radial of the VOR, not the localizer northbound.

As to the route from DNW VOR to QUIRT, the FAA should have shown on the chart that one of the approved methods for identifying QUIRT is to fly the DNW 267-degree radial to 12.2 DME.

Finally, the FAA could have exercised a couple of options to make the route from DNW VOR "NoPT." One would be to make DNW an IAF and lower the altitude to 11,000 feet, thus placing the aircraft below the glideslope at QUIRT. But that, of course, does aim the aircraft at the mountains west in the event of a blunder. My preferred solution would be to change the course to the DNW 275-degree radial, which still meets NoPT criteria, yet keeps the airplane at a safer altitude until turned inbound. Perhaps you will see a new, improved ILS 18 chart for JAC by the time this article is published.

Outside the United States, you won’t see "NoPT" charted in most countries. If the chart doesn’t have a PT, obviously all its feeder and initial segment routes are, by default, NoPT, just as in the United States. At foreign locations, where the charted procedure includes a PT, though, you have to be extra careful that you are interpreting the chart properly. If the approach is a DME arc, it is always NoPT unless the approach has some unusual alignment from a non-collocated DME. If the feeder route is a straight course with less than a 90-degree course change and an altitude that is compatible with the inbound altitude, assuming NoPT is a safe bet. But keep in mind, such assumptions are not permitted in the United States.

Capt. Wally Roberts (TWA, Ret.) served as chairman of ALPA’s former Charting and Instrument Procedures Committee and is now an advisor to that group on terminal instrument procedures. He also wrote "Air Safety Link: Is This a ‘NoPT’ Arrival?" January.