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Archive for the ‘Airport Operations’ Category

As reported in this morning’s AvFlash news, the FAA is soon going to implement a change from “Position and Hold” to “Line Up and Wait” in order to conform with international phraseology standards.  This change is expected to occur in mid-year 2010.  In fact, if you fly in and out of Canadian airspace you know that this particular phraseology has already been in use for sometime (since about March of 2008).

For those who are new to this phrase, here is a basic primer on this new phraseology:

Current Phraseology:

“Taxi into Position” or “Taxi to Position and Wait”

New Phraseology:

“Line Up” or “Line Up and Wait”

Definition: Used by ATC to inform a pilot to taxi onto the departure runway in takeoff position and wait (hold). It is not authorization for takeoff. It is used when takeoff clearance cannot immediately be issued because of traffic or other reasons.

I think short term this might be a change some may grumble about I think overall this is a good change.  I believe that standards only work when applied universally across the board.  The more exceptions that are made to a standard the better chance you have at injecting confusion and error into the system.   This not only helps U.S. pilots flying internationally but also helps reduce confusion from foreign pilots who are flying domestically within the U.S.

What are your thoughts about line up and wait?

Jim is working on his Instrument rating and spotted an interesting approach procedure:

Not surprisingly, an ILS approach will have lower minimums that a non-precision approach, such as a localizer. However, I have found at least one airport in my area where the localizer MDA (580′ MSL, 564′ AGL) is lower than the ILS DA (743′ MSL, 727′ AGL). I’d like to understand why this is true and under what circumstances I can anticipate a lower minimum for a localizer than the ILS.

Jim is talking specifically about the ILS or LOC/DME Rwy 24 approach to Bowerman Airport (KHQM) in Hoquiam, Washington. There’s an interesting (if not completely confirmed) story behind this approach in particular, but before I get into that I’ll cover the basics.

Profile view (Jeppesen format) for the ILS or LOC/DME Rwy 24 approach at KHQM.

With this approach, as with any ILS, the FAA must certify that no obstacles penetrate a predetermined gradient. This means that even at full-scale glideslope deflection, there is a built in buffer between your airplane and the ground below. If terrain or an obstacle (buildings, trees, antennas, etc) sticks into the approach path, then the FAA has two options: the minimums (ceiling and visibility) for the ILS will increase, or the glidepath angle (currently 3° at KHQM) must be increased to clear the obstacle.

With the localizer-only version of the approach, you can descend to the MDA of 580′ once past WIMET (D3.0 from the localizer). The additional distance fixes on the localizer approach permit a pilot to descend past the obstacle and land safely. Unfortunately, to answer the second part of Jim’s question, there’s no way to predict the inversion in approach minimums unless you’re intimately familiar with the airport and the surrounding terrain. The real answer is to make sure that you thoroughly brief each approach before flying it.

The specific details about Hoquiam are after the break! Read the rest of this entry »

I was listening to an ATIS (automated terminal information service) broadcast recently and something about half way through the report caught my attention.  The automated voice for the message sounded to me like it said “FDX system operational. All aircraft operate transponders with Mode C on all taxiways and runways”.

I had never heard of the “FDX system” before so when I got  home from my trip I did a Google search for “FDX system operational” but I didn’t find anything useful in the results.   There were a couple of listings about a new safety initiative by the FedEx corporation but nothing pertient to my question about the ATIS recording.

My next step was to try and insure that “FDX system operational” was really indeed what I heard on the ATIS.  I was able to track down and get the digital ATIS from FBOweb.com for the airport I was at and here is a text version of the recorded ATIS:

Read the rest of this entry »

Bob writes asking about the best place to complete a engine-run-up at a busy airport:

On a controlled field, where is the appropriate place to complete the aircraft run-up checklist? I trained at an uncontrolled field where there was space where the taxiway meets the runway to pull off to the side and do the run-up, but the controlled fields I’ve visited don’t have much space to get out of the way and are likely to have people behind you waiting to depart.

Bob, you have asked a good question, and you are right, at a busy airport, many times there does not seem to be a good place to do a run-up where you won’t throw debris or rocks at another aircraft.   My advice would be to ask ground control during your initial radio call:

“XYZ Ground, Cessna 1234 needs to do an engine-run up and is unfamiliar.  Can you suggest a place to complete our run-ups?”

You also many notice, that at some airports, there is often a holding block or waiting area for aircraft waiting on depart on an IFR flight plan.  These are sometimes even referred to jokingly as “penalty boxes” (we have all been there at least once as a airline passenger).  This kind of location is often a perfect spot to complete your before- takeoff checklist.  You could modify your radio call to sound like this:

“XYZ Ground, Cessna 1234 needs to do an engine-run and is unfamiliar.  Do you have a holding area or some other place that would be appropriate for me to complete a run-up before takeoff”

Every airport is different, but every airport, if they serve general aviation aircraft, WILL have a place appropriate for engine run-ups.  All you have to do is ask.

If you question the reasoning behind a engine run-up, be sure to take a look at my previous post discussing this subject.

Fly Safe.