Archive for May, 2008

Midair on Landing

Friday, May 9th, 2008

It’s been said many times that the most likely place for a midair collision is on final approach. Looks like it happened again last week where two Cessna 172s got together at a non-towered airport in McCall, ID. The weather doesn’t appear to be problematic and unfortunately, there were fatalities. It’s too early for specifics as to who did, or didn’t, follow procedure or whether it was just a simple failure of see and avoid.

Picture this: You’re on short final and focused on the touchdown zone. The late afternoon sun is in your eyes but with sunglasses and the visors down, it’s manageable, or so you think. The other aircraft, also on final, is just ahead, below and to the right. It might have been visible half a mile back but now is blocked by the cowl. The right seat passenger is looking at the end of the runway, just as you are. The radio is quiet or there is chatter from other aircraft in the pattern but not the collision aircraft. Everything is completely normal until….. you get the picture.

Here are some imperfect suggestions. Traffic patterns, and especially final approach, are a high risk collision area. Never mind how much time is spent there (This applies to CFIs especially) you should be on HIGH alert. The better the weather, the more uncomfortable you should be, because there are more aircraft flying. The other time to be very alert is when nobody is around except that one other aircraft unknown to you. Practice a sterile cockpit – only flight-critical discussion. This is not the time to be discussing the size of the houses. Do enlist everyone on board to look for other aircraft.

There are many time-proven procedures to review in ASF’s Safety Advisor on operations at non-towered airports. There’s more to this than meets the eye ( pun intended) .

When Your World Rolls Over

Friday, May 2nd, 2008

If you ask a roomful of pilots how many have suffered a vacuum pump failure usually one third to one half raise their hands. When asked how many have had things go South in IMC the number is much smaller but still significant. Anyone who has ever had to fly partial panel in the clouds will not soon forget the experience.

If you’d like to hear how the story unfolded for a pilot down in Florida recently, watch this real pilot story. You’ll see first hand what worked well and what the pilot would have done differently. We are all “supposed” to be able to fly partial panel approaches under Part 91 ( personal) flight operations. However, I find it intriguing that the airlines and most corporate flight departments who operate with two person crews that fly more in a month than some of us do in a year, don’t put their eggs into that high-risk proficiency basket.

Their aircraft are all equipped with backup systems that pretty much eliminate all the heroics associated with a single point failure. Dry vacuum pumps are not especially reliable and even when the mandatory replacement schedules are adhered to religiously that is still no guarantee, as the real pilot story above shows.

Here’s the real solution if you fly much IMC or at night: invest in a backup power source and/or some alternate instrumentation. This does not relieve you of the responsibility to practice partial panel occasionally but it’s very comforting to know that if and when it happens to you, the belt and suspenders on a flight-critical system will be far superior than depending on the weakest link. If you like to learn more on the strengths and weaknesses of your vacuum system go to http://flash.aopa.org/asf/pneumatic_systems/.

Your thoughts:

A. Don’t do much IMC or night, so not an issue

B. I have a back up system

C. Backup is not needed – you’re supposed to be able to fly partial panel