Thursday, April 23, 2009

A cornucopia of aviation thoughts

A Pilatus PC-12, the aircraft type involved in recent terrible Montana crash.

Ajira Air, as seen on "Lost."

Between a wonderful wife who's back to work, a wonderful-yet-sleep-adverse baby at home and the Great Job Search of 2009, it's been difficult to create a little mental elbow room for Squawking VFR lately.

Which is a shame, because the sky has been full of fertile blogging territory. Here's my best attempt to catch up with what's up in the aviation world:

Seat infringement

Last year, United Airlines officials say they received roughly 700 complaints about "seat infringement," corporate speak for overweight people allowing their girth to spill onto the poor soul sitting next to them.

United is now requiring overweight customers to purchase a second seat if they are infringing upon their seat mates and alternative seating is not available.

I have written many angry letters to United over the years. When I lived in Denver, they were usually the only airline available until Frontier emerged as a viable option. I've been ruthlessly dumped in unintended destinations, lied to about alleged "weather delays" that were not actual weather delays and generally treated like garbage.

Every time, I let United know about it.

So fair is fair: I applaud United for taking a stand, politically incorrect as it may be, against seat infringement.

I can't count the number of times I've had a flight ruined because of this awkward situation. Once, when I flew from Denver to Kansas City, the gut of the gentleman next to me engulfed the arm console and rested on my knee for the duration of our travels.

Another time, flying from Denver to Newark, the man next seated next to me couldn't rest his arms at his sides due to his girth. So instead his elbow rested in my rib cage for the entire four-hour flight.

By the end of the flight, I was ready to go berserk. You get to a point where you see an overweight person walking down the aisle during boarding and you send up a "Please God, don't let them sit next to me" plea.

No one wants to make these people feel bad, but the truth is that seat infringement is every bit as invasive, bothersome and unjust as the scourge The Recliners thrust upon us traveling folk.

I've paid for my postage-stamp-sized space at 35,000 feet. I'd like to use it.

Bravo, United.

Autopilot cited in crash

The National Transportation Safety Board issued a recent report on the 2007 crash of a Citation jet crash that killed six people, including four members of a University of Michigan organ transplant team.

The report concludes that one of the pilots inadvertently turned on the plane's auto pilot instead of the yaw damper, which is what he allegedly intended. The two buttons are next to each other on the console.

Sad deal all around.

Like the recently detailed Buffalo crash, I'm really struck by the simplicity of this conclusion. Are they really saying that if the pilots had only realized that they had made a rather innocuous mistake, they could have simply turned off the auto pilot and not crashed the plane?

Yeah, they are.

I have to think there's more to this story. There just has to be more there.

Auto pilots make a loud, audible beep when they are engaged, and then again when they are disconnected. This feature was created in response to the Eastern Airlines L-1011 crash in 1972 that I've mentioned before, when the crew became so engrossed with a small problem they didn't realize the auto pilot had disengaged and put the plane on a small, gentle descent into the swamps of the Everglades.

With the audible warnings, I just have to think the crew of this Citation knew the auto pilot was on.

Incidentally, my scariest moment in roughly 680 hours of flight time came thanks to a malfunctioning auto pilot.

On August 22, 2006, I was flying with my friend Tim, a fellow CFII, from Jefferson County Airport to Platte Valley Airpark, an all-but-abandoned landing strip about 17 miles directly north of Denver International.

The flight was mostly for fun, but I was also conducting Tim's biennial flight review.

Denver's Class B airspace extends over Platte Valley at 7,000 feet MSL, so we were below that at 6,500, which means approximately 1,500 feet above ground level.

We were in level flight squawking VFR on our way to Platte Valley with the auto pilot on when, without warning or reason, it started trimming the plane into a pitch-up attitude.

It kept trimming the nose up until the trim wheel hit the backstop. The nose rose at least 15 degrees pitch-up and would have easily gone through 20 -- past the critical angle of attack, if you remember my stall lesson from the Colgan post -- had Tim not fought to keep it down with all his might.

The sudden trim-up was bizarre, but the solution here seemed simple enough. Turn the auto pilot off.

I was in the left seat, and clicked the auto-pilot disconnect button near my left thumb on the yoke. It made the loud, audible beep that signified the disengagement. Except the auto pilot didn't turn off. It retained its grip on the yoke and trim wheel.

Tim cut the throttle to help him fight the pitch-up attitude, then we reversed into a pitch-down attitude of about 15 degrees. This wasn't good either.

At the same time, I pressed the auto-pilot button on the avionics console, trying to turn the damned thing off. Again I got the verbal cue that it had disconnected, but it again didn't actually disconnect.

Tim kept fighting the auto pilot. (This is really hard, by the way. Sort of like trying to steer a car after the power-steering quits).

I don't remember how far we deviated from target altitude, but it's possible that we busted up into the Class B or possible that we sunk below 6,000. I really don't remember at this point, but I know our altitude fluctuated by several hundred feet.

What I do remember our general flight path oscillating like a roller-coaster as we did this pitch-up, pitch-down dance. I remember being worried that the full-aft-trim auto pilot was going to stall us, and that with its grip on the yoke, the AP would somehow complicate our stall recovery.

Then I had the brilliant idea of pulling the auto-pilot circuit breaker. I reached under the yoke, and popped it out.

That worked.

The auto pilot released its grip on the flight controls, we leveled off and shuffled along to Platte Valley without further incident.

All in all, the whole thing probably lasted 30 seconds. Maybe 40. We never reached a crisis level, and the whole was over by the time we did anything but react and respond.

When we returned to our base at Jeffco, the owners of our flight school seemed incredulous when we explained what happened. Had we not been two CFIIs, I really think they would have assumed that one of the students had messed something up or not used the AP correctly and dismissed the incident.

But after our encounter, every student at our school got an auto pilot lesson, one that included learning exactly where the AP circuit breaker was on the dashboard.

Tim recalls: "It does scare me to think of what would happen to most folks flying those planes that don't get an autopilot lesson. Can you imagine that happening to a student during their first solo?"

Prior to this incident, I had suffered other auto pilot malfunctions, far less serious - things like it not picking up the localizer on a practice VOR instrument approach or not maintaining the programmed 500-foot-per-minute descent I had asked for.

One of my own instructors had once explained to me that the AP in the 172s gets "hot," and then it doesn't work so well. I have no idea if that's true or not, but there were times that the AP box in the avionics stack was indeed very hot, and that also worried me, from an electrical perspective.

I'm sure the auto pilot in the Cessna Citation II that crashed off Milwaukee is far more advanced than the rickety ones installed in our 172s and I want to make sure that I'm clear that I'm not comparing the two. I'm also not suggesting that what happened to me is what happened to the pilots of the U-M organ transplant plane.

I'm just relaying an experience with an auto pilot.

And why I have an inherent distrust of them.

Elsewhere in the media

I wrote a little bit about the role pilot fatigue may have played in the Colgan crash, and its impact in other aviation accidents.'s Patrick Smith goes further in-depth on the topic in this report, which is well worth a read, unless the idea of your pilots falling asleep at the yoke at 35,000 feet makes you uneasy.

Passenger lands plane

You may have read this story, in which a passenger took over the controls of a twin-engine turbo-prop King Air and successfully landed after the pilot died in Naples, Fla.

When I first heard this story, I sort of yawned, because the "passenger" was a private pilot and I figured the mainstream media was merely sensationalizing the story like it does with almost every oddball aviation occurrence and that he had some degree of turboprop experience.

But the more I read and the less I assumed, the more impressed I became with Doug White.

It turns out that White is a private pilot with a mere 130 hours of flight time, all in single-engine planes. He had never before manned the controls of a twin, which is a significantly different animal.

The general flight concepts are the same no matter what aircraft type: Pitch plus power equals performance. But comparing the flight characteristics of a single-engine Cessna with the King Air, well, it'd be a little like trying to fly a kite versus an anvil.

Add in retractable gear and a host of other complex systems that he wasn't accustomed to, and White had his work cut out for him.

I'd stop short of calling it a miracle, because his previous experience clearly gave him the necessary stick-and-rudder background to fly and land. But it's nonetheless a gutsy, poise-under-pressure performance that brought out his best under unfortunate circumstances.

"Lost" in aviation translation

For a show that prides itself on nailing down every last detail, one recent episode of my favorite television series left me a little disappointed.

If you watch Lost, you probably remember that the ol' gang returned to the island a few weeks ago by boarding a fictional Ajira Airways flight and flying straight into the path of the paranormal phenomenon that landed them on the island in the first place.

The gang boarded Ajira flight 316 in Los Angeles, which had a stated destination of Guam. But then the producers showed the Ajira flight in question being conducted in a Boeing 737-800 model aircraft.

This is a careless oversight by Lost producers: There's no airline on earth that's running trans-Pacific service with a 737, much more of a short-haul jet.

Perhaps an even worse transgression? Inside the plane, they showed Hurley, Benjamin Linus and company sitting in the first-class, top portion of a double-decked cabin.

The 737 doesn't have double-decked cabins.

In passenger service, that honor belongs only to the 747, a completely different bucket of bolts.

All around, a bad job by the Lost crew on simple technical matters that should have been caught before production.

Skepticism on Montana crash cause

I have my doubts that the terrible plane crash that killed three families in late March was due to an overloaded airplane, the cause drawing a lot of early speculation/attention.

Yes, there were 14 passengers aboard the 10-seat plane. Many of them were children, who obviously weight less than adults.

Furthermore, and probably more important, I'd expect an overloaded plane to crash on takeoff and not upon landing, after it had flown 1,000 miles and burned off hundreds of pounds in fuel.

Keep an eye on whether the investigation turns not only on weight, but on how that weight was balanced throughout the plane.

A plane can be at or under its maximum gross weight, but it also must be "balanced," i.e. the center of gravity of that weight must lie within a certain range, one usually measured in inches from the nose of the plane backward.

That distance is called the "arm."

Exactly where along the arm the center of gravity lies can affect the way the plane handles. If the C.O.G. lies outside the scope of the predescribed range, it can adversely affect those handling characteristics.

Still, I don't think the Montana crash is one that will ultimately be attributed to weight or balance issues. Investigators need to know why the pilot diverted from Bozeman, the original destination, to Butte.

One key question for me, beyond the weight and balance issues and the decision to divert, is how much prior experience the pilot had in the Pilatus PC-12.

I hope it's a lot. The PC-12 is one of the most powerful single-engine planes on the market. For all intents and purposes, it's a business jet that can zoom around at 350 knots. Except it's a powerful single-engine turboprop with the propeller mounted on its nose.

The one thing that's always struck me about the PC-12 is that any yahoo with a private pilot's license and complex and high-performance sign-offs in their logbook can legally fly an aircraft that's really one no beginner should be anywhere near.

I have no idea how many hours the pilot in this particular crash had in type. I really hope it's a ton and that experience has nothing to do with this terrible accident.

But when I heard it was a Pilatus involved, it reminded me that I've always thought it was odd that such a powerful plane could legally be flown in the hands of a short-time private pilot.

Close that loophole somehow, will you Federal Aviation Administration? If it didn't kill anyone in this crash, it's a matter of time before it's a factor somewhere else.

Coming up

If you're a frequent flyer and you love your family, you won't want to miss Squawking VFR's upcoming special report on the comparative safety of regional airliners and their legacy counterparts.

I've examined databases and crunched numbers for my first-ever special report. Let's just say the conclusions are eye opening, alarming and frightening. You don't want to miss it.

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