AOPA ASI Blog: Leading Edge

VFR pilots getting into clouds is an old story. According to the 2007 Joseph T. Nall Report, 20 single engine pilots had accidents, most of them fatal, from this type of weather encounter. Everyone in the business warns against VFR cloud busting, but we don’t know how many successful attempts are made.

Perhaps the odds on any particular flight are pretty good, which is why some pilots continue to press on. In many cases though, do you ever wonder why the pilot is the only one who can’t see looming disaster? ASF developed a case study on the topic which recreates one of these tragic accidents .

It’s been one of our best. One recent reviewer said, “This has to be one of the best courses I have ever taken or viewed. …Not only is the material of great use, the emotional value hits home. You can’t help but to watch this and know what that pilot was going through. The use of the simulation as a component of this training was very helpful. Very, very well done.”

I encourage you to watch and send us your comments – constructive criticism is always welcome along with kudos. Better yet, if you know a VFR pilot who doesn’t get the cloud thing, forward the link!

A friend called me the other day to say that several times in last few months he was vectored to an ILS in such a way that his autopilot was unable to capture the glideslope. For those who shun autopilots this may not be an issue, but for many professionals, especially those flying single pilot in high performance aircraft, routine autopilot use for an IMC approach is standard.

To my knowledge all autopilots, when armed for an approach, must intercept below the glideslope for capture to occur. Diving to capture a glideslope makes it tough to stabilize the approach.

My friend called the tower after landing and in the ensuing discussion found that there was some confusion about why this was important. The controller’s guidance says, “For a precision approach, (when vectoring an aircraft to an approach) at an altitude not above the glideslope/glidepath or below the minimum glideslope intercept altitude specified on the approach procedure chart.” That is, they should put you in a position to intercept from below the glideslope.

In the example above, by my interpretation, outside of FREST you should be at 2,400 and between FREST and MEANS it would be 2,100.

One way to make sure that happens is to ask for a “coupled approach,” which will remind ATC that the autopilot will do the honors.

Has anybody else had any difficulty in this area recently?

It’s been a tough year for Airbus on the automation front. First, NTSB was concerned about incidents involving total glass failure. Now comes an incident where a Qantas Airbus 330 cruising in the flight levels over Australia twice decided it had a better idea and plunged off altitude dropping 650 feet the first time and 400 feet again after the pilots returned it to the original altitude.

“The jetliner experienced a glitch in the computer unit that uses sensors to detect the angle of the plane against the airstream,” says Julian Walsh, chief air investigator at the Australian Transport Safety Bureau. “One of the plane’s three units malfunctioned and sent the wrong data to the main flight computers. It is probably unlikely that there will be a recurrence, but obviously we won’t dismiss that.”

I am sounding like a total Luddite to once again remind GA pilots that autopilots and flight management systems are usually benign tools but when they turn on us, however rarely, shock and awe has to replaced quickly with pilot in command thinking. The mutinous gear must be quickly and positively isolated. At this point you are operating in an abnormal situation – not an emergency but degraded. Under the yellow flag (NASCAR terminology) don’t be afraid to ask for ATC assistance as needed. If you’re single pilot in IMC as for vectors to a nearby ILS etc.

At least 40 people were injured in Airbus mishap as they flew about the cabin. That’s why keeping your seat belt fastened at all times is a really good idea both in light and heavy aircraft. Ya just never know when the genie is going to get out of the bottle.