Thursday, April 21, 2011

Head-Shakin’ Mode

A reader sent me a safety recommendation (a .pdf file) from the NTSB that was based on a recent preliminary accident report (a .pdf file) from the NTSB. I don’t have time to analyze it right now, but like a moth to a flame, I couldn’t help but start.

The first read-through had me shaking my head. The safety recommendation has some stuff on ERAM in it. But the basic ATC information was deeply depressing to me. I could write a dozen blogs on this information alone. Before I could pursue that, I wanted an idea of the terrain (the accident was a controlled-flight-into-terrain type.) So I took the NTSB data, went to and plugged in the route of flight. The flight departed from JAC (Jackson Hole, WY.)

”...the filed route was DNW VOR...”

”...the filed altitude was 9,000 feet...”

I haven’t done this in a while (I used to use all the time for research) and the info available now is just amazing. You can even look at the sectional charts.

(click to enlarge)

Just in case you can’t see it at this resolution, the red line (the route of flight) goes right through “TOGWOTEE PASS”, southeast of DNW VOR. There are 11,000+ ft. mountains on the north side of the pass, 10,000+ ft. mountains on the south and the red line actually runs right through the terrain numbers on the chart -- “9658”.

”...the filed altitude was 9,000 feet...”

I know there are some non-aviation folks reading this blog now due to recent events. I implore you, don’t try to interpret what you don’t understand. The NTSB final report will be out soon enough. The pilot in this accident didn’t even get to fly the route he filed. I’m talking about human factors here, not the cause of the accident.

For my regular aviation readers, I’ve said it a million times in a million different ways;

Same Old Safety Problems

”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.”

We’ve expended barrels of ink this week on the subject of sleepy controllers. Ask yourself a safety-rep question; How many people died in the numerous incidents reported? That’s right -- zero. It’s a real safety problem -- there’s no denying it and I’m not going to make light of it. But people actually die in the CFIT (Controlled Flight Into Terrain) accidents. And despite all the gee-whiz technical solutions we come up with, people still die in them. I just finished talking to another reader about this same phenomenon. We insist on focusing attention on the machines -- technical solutions -- instead of the people -- human solutions. Technology has its place. But it’s the people that matter.

I have a million things I need to do today besides writing about this. I’ve got to go. Procedures are written for a reason. We have more information available now that ever. We have machines, computers and software that are absolutely incredible. None of it is a substitute for using your head. Think. Think “non-radar”. Stay alive.

Don Brown
April 21, 2011

1 comment:

John Ewing said...


My reading of this accident is that it doesn't hinge on direct-to or non-radar environment operations. What it does involve is a pilot who appears to have done inadequate pre-flight planning. Unfortunately this happens all too often.

If memory serves me correctly, the M20J has a service ceiling of 18,800 feet - that's the altitude at which the aircraft can maintain a climb of 100'/minute. The climb performance above 14,000 is going to be marginal under the best of circumstances.

The pilot filing 9,000 as his requested altitude would also seem to suggest the pilot hadn't thoroughly thought through the minimum en route altitudes in the area. His clearance was 16,000, he requested 14,000 (which wasn't going to work) and poor controller coordination meant there was a disconnect between the pilot's expectation of staying at 14,000 and the second controller's expectation that the aircraft would climb to 16,000.

ERAM apparently doesn't give the controller low-altitude alerts when radar contact is lost, but it does continue to predict the aircraft's track based on the aircraft's last known track and ground speed.

The final straw was that the pilot appears to have entered a mountain wave and the inadequate altitude combined with the already marginal climb performance of a non-turbocharged singe piston: The aircraft was probably overcome by the downdrafts that exceeded the aircraft's climb performance.

Even if the aircraft had climbed to 16,000, even if the controllers and the pilot were on the same page, this was one risky flight.

I think this accident is a good illustration of something that many non-pilots don't seem to understand - The pilot-in-command is the only one who can fly the plane and if the PIC makes unrealistic preflight decisions or unrealistic requests from ATC, we can't expect controllers, ERAM or NextGen to save that pilot's bacon.