Thursday, August 06, 2009

Same Old Safety Problems



I had a brand new safety rep. write and ask for some advice on doing the job the other day. One of the things I mentioned was the NASA Aviation Safety Reporting System (NASA ASRS). It is -- and has been for many years -- a great resource for finding trouble areas.

If you’ll go to the main page at ASRS, you’ll see in the middle blue box, under “quick links”, ASRS Database Online. The search function takes some getting used to. (Okay, a lot of getting used to. It’s pretty awful but it works.) I started by just searching in the “Text” field (after clicking through the “Start Search” button). I started with “ZTL” just to see what was going on at my old stomping grounds (Atlanta Center). I wasn’t the least bit surprised to see that the first report was about the Asheville, NC airport.

Asheville (as we all know) is surrounded by mountains. It’s a “challenging” airport. That’s code for, “If you dot your “i”s and cross your “t”s it is safe. If you don’t, it will kill you.” I’d venture a guess that 90% of Asheville’s (the identifier is AVL) problems occur on the midnight shift with airline-type aircraft.

The AVL Tower closes at 11 PM and Atlanta Center takes over the airspace. Airline pilots (most of them) just aren’t used to operating in this type of environment. In the dark. Surrounded by mountains. At least not on the East Coast.

You see, when AVL Tower closes, the place becomes more like an uncontrolled airport out West. Radio and radar coverage are limited. Did I mention the mountains ? If everyone (pilots and controllers) would forget about going direct, fly the airways and fly the approach procedures -- if they’d “think non-radar” -- things would work out just fine. But people don’t do that anymore. And when the radar world -- “I can see them on the scope”/”Follow the magenta line” -- doesn’t work, things start falling apart.

I know all this will just be confusing to the non-aviation readers. Sorry, but there’s nothing to be done about it. The best analogy I can come up with is the difference between driving on the interstate and a dirt road. The airline pilots are on the interstate all day. But at AVL -- when the Tower closes -- you’re on a dirt road. Things get “bumpy”. If you’re mentally prepared for it, dirt roads aren’t a problem. But going from the concrete to dirt at 55 MPH is never a good idea.

Here’s the report “narrative”.

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ACN: 833120 

Narrative

We pushed late for a late evening flight to AVL. I was the pilot flying and the flight was normal until the descent into AVL was initiated. ATC issued a descent to 9,000 FT MSL. I descended to 9,000 FT MSL and did not receive a further clearance for lower. We queried ATC and were handed off to another controller, while still at 9,000 FT, flying through the LOC, and less than 20 miles from the field. The second controller cleared us down to 7,000 FT and gave a vector back to the LOC at approximately 15 miles from the field. I rejoined the LOC and had the runway in sight when we were cleared for the visual approach to Runway 34 in Asheville, still outside the marker. I was in the center of the LOC but well above GS when we decided to execute a go-around. Upon execution of the go-around, the Center Controller who cleared us for the approach informed us that the MVA in the area was 7,000 FT and that he could not vector us for the approach. He cleared us to the OM, Broad River NDB, for the full approach. We completed the procedure turn, and were at the appropriate altitude to continue and complete the approach to a landing. This occurred because ATC coverage and communication were poor, at best. If the first Controller knew that he would not be providing ATC services to the flight all the way until the landing, he should have coordinated with the second Controller prior to handing us off. The first Controller handed us off extremely high and extremely close to the airport. We could not complete the approach from the position that we were handed off from. In clear VMC, calm wind conditions, this resulted in a missed approach. In more challenging conditions, this could easily have contributed to an accident. There should be sort of a plan and realistic expectations when the ZTL controllers are working a late night into AVL when the AVL Tower and Approach Control are closed. Though it is possible that the flight was handled in accordance with applicable regulations, the reality of events shows that safety was clearly degraded.

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Here’s the Approach Plate for the ILS34 at AVL. (Click to enlarge.) Note the 6,060 foot obstacle to the NW of BRA. “Mountainous terrain” -- add 2,000 feet and that gives you an MIA of 8,060, round it off -- 8,100 MSL. (I was asked about that just yesterday.)



If you want to search through the NASA ASRS database, you can find a dozen versions of that same story at Asheville. Just go back to the search function and type “AVL” in the “Location” box. Or -- as I’ve always encouraged pilots to do -- type in your home airport’s identifier. You might be surprised about what you can learn.

Don Brown
August 6, 2009

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