Two weekends ago, a widely disseminated AP story discussed the carriage of pets aboard commercial flights. Per a new law enacted by Congress, the report explained, airlines are being forced to keep tabs on exactly how many animals are killed, lost or injured on flights. An estimated 2 million animals are transported by U.S. airlines every year, up to 1 percent of which, according to some sources (I suspect the actual percentage is much lower), are mishandled.

A quick scan of the article reveals three mistakes. First, Delta Air Lines is misidentified as "Delta Airlines." Later, in something of an amusing corollary, United Airlines is misidentified as "United Air Lines."

More egregious, the piece goes on to tell the story of a cat named Hereford, who suffered an untimely demise in the cargo compartment of a Delta jet during a flight to Greensboro, N.C. "Hereford died from either cold or lack of cabin pressure," it states.

This was especially timely, as the article came on the heels of an Ask the Pilot discussion about cabin pressure, in turn prompting a flurry of "But you said..." letters to appear in my mailbox.

For the record, it's impossible for Hereford the cat to have died from a lack of cabin pressure unless the passengers too were similarly affected. An airplane's fuselage, both in the main cabin and throughout the lower deck holds, is pressurized as a single vessel with a uniform value throughout, measured as a pounds per square inch "differential." You cannot have varying differentials within the same fuselage. The only catch would be if Hereford were somehow placed in a totally unpressurized zone, like a landing gear bay or deep within the tail cone beyond the aft pressure bulkhead. But he was not.

Temperature was the more likely culprit. Normally, pets are confined to designated underfloor compartments that are heated and cooled as needed (sometimes automatically), but depending on weather conditions and the type of aircraft, maintaining specific temps can be tricky. Not only during flight, but on the ground too. Several years ago, Northwest Airlines became the first carrier to ban pet carriage during the summer, when tarmac temperatures soar and compartments are difficult to cool.

The AP story was penned by Leslie Miller, who handles most of that organization's aviation assignments. Overall I'd give Miller a B-plus for accuracy, which is pretty good for such stories. Miller's latest, a report on the release of the cockpit transcript from a Pinnacle Airlines (Northwest Airlink) regional jet that crashed last October, was errorless and well done.

If you missed it, that was the plane that went down during a maintenance repositioning flight when the crew decided to "have a little fun" by taking the 50-seater to its maximum allowable altitude. The aircraft crashed after both of its engines failed and could not be restarted.

Speaking as a pilot, I don't understand the attraction of lugging a plane to the edge of its altitude envelope, but the Pinnacle crew certainly found it a rush. "This is the greatest thing...," the first officer is heard saying moments before the RJ became a 20-ton glider. It then wobbled into a residential area of Jefferson City, Mo. Both crewmembers perished.

Once again Miller's AP coverage had uncanny timing, as I'd just published a column about engine failures and a plane's subsequent ability to glide. After hearing of the Pinnacle affair, my boast that even the largest planes are able to keep flying sans thrust confused some people. "If what you said is true," asked a reader, "why couldn't those guys have made it to safety?"

The crux of my point was not that an engine-less plane is guaranteed a safe landing, only that it will not drop like a stone, as many people think. In fact the disabled RJ was able to glide just fine, albeit into a neighborhood instead of onto a runway. Gliding itself is one thing; gliding to a particular spot requires skill and luck. And of course, there's only a certain radius of opportunity once your propulsion is gone. The Pinnacle pilots were reportedly within gliding distance of up to five different airports, but in the throes of their emergency were not able to accurately fix their descent. Considering the circumstances, that's not terribly surprising. They fell about two and a half miles short of the runway at Jefferson City Memorial.

The history of modern civil aviation is hardly rich with cases of aircraft suffering multiple engine loss, but at least two other crews -- those of an Air Canada 767 and an Air Transat Airbus A330 -- made it to a runway after total failure. (See this column to read more on engine failures.)

But never mind gliding. If the RJ was factory certified to operate at 41,000 feet, why did its engines die when it got there, and why could they not be restarted?

It'll be some time before the NTSB and FAA reach official conclusions, but evidence indicates the dual failure was not the result of the high altitude itself. Rather, during the climb, the crew may have inadvertently slowed the jet to the point of stall (that's an aerodynamic stall, not a powerplant stall), with the resulting airflow disturbance badly damaging the engines. The trouble began when the pilots set their autopilot's climb function based on rate instead of speed. At lower altitudes that's an acceptable option, but at 41,000 feet the atmosphere is very thin and airspeed margins become critical. As the plane leveled off, it struggled to maintain the assigned height, slowing further and eventually stalling. Turbulent currents then boiled over the wings while the engines, still at a high power setting, gasped for air, the sudden stress resulting in seizure of internal components.

What annoys me most about coverage of the Pinnacle crash is the repeated invocation of the "have a little fun" line heard on the transcripts. Though it makes a provocative headline, the comment is pretty meaningless out of context. Taking a plane to its maximum allowable altitude is not necessarily a reckless act, and the pilots were not admitting to such. The accident, investigators are likely to conclude, involved a serial of small errors rather than a single act of endangerment.

For further reading, lo and behold, Matthew Wald's June 14 article in the New York Times does an outstanding job on the Pinnacle crash. It's accurate, comprehensive and informative. Wald deftly explains the technicalities of engines and stalls without the usual distortions and silly-sounding euphemisms.

So, anyway, with all of that cleared up, there remains one boggling mystery. Would Leslie Miller, Matthew Wald, or somebody, anybody, anywhere, please offer an explanation for the following Associated Press photograph, which appeared last Saturday in the Boston Globe (from which the included scan is taken) and elsewhere. There was no accompanying text beyond what is seen here.

When I first noticed the item from the corner of my eye, I expected the caption to read: "Indiana family arrives in Mecca to begin Hajj." Except, wait, it's June and the Hajj is over, and pilgrims going to Mecca at least wear sandals.

To those who've e-mailed to ask why a ruptured hydraulic line mandates that a family don white gowns and parade barefoot through an airport, I'm afraid I have no answer. If you wonder why aviation is so colored by misinformation and urban legends, it's bizarre snippets like this that leave people to cook up nutty theories.

I suppose it has something to do with hydraulic fluid being unfriendly (did you know a severed line can, if still under system pressure, subject a passerby to a razor-like jet of high-velocity fluid?). But if I were of the slightly more paranoid sort, I'd think the AP was intentionally messing with me.

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