Twice in the last couple of months I’ve been surprised by changes in FAA documents and procedures—fortunately in both cases while I was safely on the ground.
The first came while I was getting an instrument proficiency check in preparation for a planned summer flying vacation. I was also aware that my friend and longtime CFI Larry hadn’t had a chance to get night current, so I scheduled an evening session, figuring we could do hood work for an hour or so and then do night work in the pattern. Of course at this time of year that would require operating pretty late.
After about half an hour of touch-and-goes (and a VOR check) on my own, I picked up Larry and got a departure to the north. He had me climb to 3,500 feet MSL, then do steep turns, slow flight and approach a stall—all under the hood.
Then I called for an ILS at KMOD—which I hand-flew; missed; came back for an RNAV approach which I flew on autopilot; and finally a VOR-DME approach on partial panel. Larry announced he was satisfied by my performance—and so was I! By then the sun had set, so we stayed in the pattern for stop-and-go work to get both of us night current.
As we tied down the airplane by flashlight, Larry asked if I’d ever considered flying into a really cold airport. I wasn’t sure what to make of that—in the summer I don’t tend to think much about cold-weather flying—but when we sat down later to do paperwork, he asked me to look up a plate in ForeFlight for South Lake Tahoe (KTVL).
It featured a symbol I’d never seen before, an inverse snowflake icon. I wasn’t immediately sure where to look for a definition of that, so Larry pulled out his old-fashioned paper Jeppesen plates, where the same thing is indicated by the notation “Cold Temperature Restricted Airport” and a table of correction factors.
I found the same information in the Digital Terminal Procedures supplemental document in ForeFlight (if you get paper charts, it’s in the explanation of terms/landing minima section at the front of each volume of terminal procedures). I’ve reproduced it in the figure below.
According to a related notam, the FAA has gotten concerned over the potential for significant altimeter errors in extremely cold weather. (Refer to Resources for the URL. —Ed.)
You may recall from primary flight training that temperature significantly above standard will cause the altimeter to read low, and temperatures below standard will cause the altimeter to read high. This is covered in the AIM under section 7-2-3, titled “Altimeter Errors.” There you will find a table identical to the one in the figure.
In the PDF version of the AIM (dated April 3, 2014; Change 2, Jan. 8, 2015), you’ll also find the following under 7-2-3e:
Pilots are responsible to compensate for cold temperature altimetry errors when operating into an airport with any published cold temperature restriction and a reported airport temperature at or below the published temperature restriction.
Based on the notam langu
age and this newer language in the AIM, cold temperature corrections are now mandatory for instrument approaches at specified airports. Each approach which is cold temperature-restricted has an associated temperature limit.
For KTVL, it’s –21 degrees C (–6 degrees F). That’s not a temperature you’ll see very often, but it can happen—according to one website, the temperature hit –14 degrees F (–26 degrees C) just two years ago.
If temperatures were that extreme on a day when you were flying into KTVL on an instrument flight plan, since it’s below the limit, you’d be required to apply a temperature correction while on the approach. For the GPS 18 approach, the first fix is OBAVE, where you must be above 10,800 feet MSL. The airport elevation is 6,264 feet, so OBAVE is 4,536 AGL.
Looking at the table, and selecting the most conservative correction, I get 950 feet—add that to 10,800 and you need to fly at 11,750 feet to make sure you’re high enough.
Similar (though less extreme) corrections are required at the other fixes on the approach; and finally, at the minimum descent altitude, which is 7,160 feet MSL (900 AGL) for a straight-in approach. Again, looking at the table for –26 degrees C, that requires a correction of 130 to 170 feet. To be safe, I’d use the higher number—so the MDA is now 7,330 feet MSL (1,070 AGL).
One question Larry asked me—and I haven’t quite figured out—is whether you’re expected (or for that matter, allowed) to interpolate between cells in the table. That’s not clear from the notam or AIM language, and it could be an issue, particularly on an approach with mandatory limits.
In my opinion, this is an awful lot to ask a pilot to do while flying in the soup, and my immediate reaction after looking at the notam was to say that if I was presented with flying IFR under these conditions, I’d start wondering just how badly I wanted to make that flight… but I’m not used to flying in cold weather.
Folks who fly regularly east of the Rockies in the winter might well have a different reaction. And incidentally, for those lucky enough to fly behind a glass panel, you might check to see if your avionics offer a temperature compensating feature—if so, the notam says you should make sure the feature is operating so that you’ll automatically fly at the corrected altitude. And according to the AIM, if that compensation feature is inoperable, you’re required to manually correct.
Either way, you are supposed to let ATC know what you’re doing. For the example above: “Norcal Approach, N4696K requires 11,750 for cold temperature operations until OBAVE” and similar calls as you fly the approach.
And, by the way, the need for altitude corrections (and calls to ATC) applies to the missed approach procedure as well.
The second surprise came in AOPA’s ePilot mailing list which I subscribe to. A headline caught my eye and then I read on down until I was stopped by an item that announced “End date set for Flight Watch frequency.”
Sure enough, as of Oct. 1, 2015, the FAA will no longer provide nationwide En route Flight Advisory Service (EFAS) response to the Flight Watch call on 122.0 (and various discrete frequencies used at high altitudes).
Instead, EFAS is being “consolidated into routine in-flight frequencies to eliminate unnecessary duplication of service… [EFAS] will now be available on the same frequencies used to open/close flight plans or to receive updates on Notice to Airmen (NOTAMs) or Temporary Flight Restrictions (TFRs),” according to an FAA website.
What that means is that instead of calling “Flight Watch, N4696K near Squaw Valley VOR” on 122.0, you would call Flight Service on the nearest RCO frequency—in this case, 122.25 (Reno Radio), and request a weather update or give a pilot report.
On the whole, I don’t think this is a big problem—it just requires us to find the nearest Flight Service frequency (a feature that’s built into the Garmin GNS 530 we have in N4696K, and easily found using electronic flight bag software) instead of always using 122.0.
In busy airspace like Southern California this change may have a real benefit, since pilots in different sectors won’t all be stepping on each other’s radio calls while trying to get updated weather reports in marginal conditions.
Flight Watch isn’t the only service the FAA is changing—according to the same website where I got the above details, the seldom-used Hazardous Area Reporting Service is also being discontinued in October.
Longer-term changes mentioned on that site include improved emergency response on Guard (121.5); eliminating legacy Airport Advisory Service at 19 airports; requiring the International Civil Aviation Organization (ICAO) flight plan form for domestic VFR flights; and “alternative solutions” for pilots to speak directly with ATC when requesting instrument clearances instead of having them relayed by Flight Service.
There’s also mention of an option for automatically opening and closing VFR flight plans, which I suspect will require ADS-B equipment. (See Resources at the end of this column for links to this information via CessnaFlyer.org. —Ed.)
Now for some sad news. In the last couple of columns, I mentioned plans for my wife and I to fly ourselves back east by way of Mount Rushmore in July. I’m sorry to say that trip never happened. Unfortunately, Kate’s ovarian cancer is progressing (she was off chemo at the time) and there was just too much risk of finding ourselves halfway across the country with her too sick to travel.
We wound up letting Southwest Airlines fly us to Ohio, so Kate and I were able to attend her parents’ 60th wedding anniversary. She’s back on chemo now, and I have hopes that we may be able to make a trip to Rushmore later this year.
Meanwhile, I hope you’re all enjoying the autumn weather—but remember, winter will roll in eventually, and you’ll want to be ready for it when it comes. Happy flying!John D. Ruley is an instrument-rated pilot and freelance writer. He holds a master’s degree from the University of North Dakota Space Studies program (space.edu) and is archivist for the Hubble Space Telescope (HST) operational history project. Ruley has been a volunteer pilot with ligainternational.org and angelflight.org, two charities which operate medical missions in northwest Mexico and provide medical patient transport, respectively.
Aeronautical Information Manual, Changes 1 and 2 dated Jan. 8, 2015
Published by U.S. Dept. of Transportation Federal Aviation Administration
Restricted Airport Notam
CessnaFlyer.org/ColdTempNotamFlight Service National
Airspace Initiative (FSNI) FAQs