Tuesday, April 14, 2009

Much-a-do about Machado

In the May 2009 edition of Flight Training magazine, Rod Machado was asked, “When should a student start a descent for landing while in the airport traffic pattern?” His response was intriguing which, in this context, I would say is incorrect. The information he provided was, in one pilot’s opinion, miss-directed, particularly since it was given to a student.

Mr. Machado said he didn’t side with the Airplane Flying Handbook which advocated that the landing descent within the pattern should start abeam the numbers on down wind. He prefers to wait to start the descent until having turned final in order to preserve altitude and avoid what he rightly referred to as the disparate and potentially dangerous nature in which pilots exit and enter the pattern. In other words, because people don’t conform to the standard, disregard the standard as well and stay high.

However, the FAA’s Aeronautical Information Manual states in 4-3-3 to:

1) Maintain pattern altitude until abeam approach end of the landing runway on downwind leg (implying that you start descent at that point)

AND

2) Complete turn to final at least ¼ mile from the runway.

If one assumes pattern altitude to be 1000 feet above runway elevation, then maintaining that altitude until turning final while intercepting the proper 3 degree glide slope would mean flying the downwind far enough down range that the turn from base to final would be nearly 2/3 of a mile from the runway. That’s more than twice as far out as the minimum recommended by the FAA.

While the FAA doesn’t specify a maximum distance at which to turn base to final, it would be prudent to intercept the proper glide slope close in and ensure that you can always make the runway. In doing so, the pilot would be following the FAA’s recommended procedure.

Alternatively, the pilot could maintain pattern altitude until turning final and do so inside 2/3 of a mile. This method, however, results in:

a) being high on final
b) making a steeper than normal approach, possibly resulting in too much speed during landing,
c) intercepting the glide slope from above as opposed to doing so from below which is the FAA recommended M.O.

In neither instance above does it appear prudent to follow the advice given the student by Mr. Machado. Little good can come of disregarding the FAA’s recommended procedures.

One can argue the merits of the FAA’s recommendations during a philosophical discussion over adult beverages. However, telling a student that you disagree with the FAA and that it’s ok to consider alternative pattern procedures is not sound advice. Doing so in a national publication may be even less judicious. Then again, Mr. Machado is an aviation comedian. Maybe he was just being funny?

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