Defining Alternates

Many pilots miss the boat on applying alternate minimums when flight planning


The article Alternate Realities [Airmanship, January] left out probably the most important and least understood criteria for alternate airport selection. Mr. Veillette starts out talking about the ceiling and visibility requirement of 600 and 2 for precision approach and 800 and 2 for non-precision approach equipped airports, and goes on to say that there is more to it than that. Unfortunately, he then goes on to only explain half of the remaining equation – the most important and most overlooked part.

In the authors explanation he is referring to the government charts, not Jeppesen. The government charts use the A in the triangle to define IFR Alternate Minimums. First, you must consult the appropriate IAP (instrument approach procedure) for the airport and procedure to be used. If there is no A in the triangle, standard minimums apply (600 and 2, or 800 and 2).

Obviously, as Pat explains, if there is an A in the triangle with an NA, the procedure cannot be nominated as an alternate on the IFR flight plan. The important one that seems to be the most misunderstood is the A in the triangle and nothing more. When you see this convention it means that non-standard minimums apply. You must then consult the IFR Alternate Minimums portion of the Terminal Procedures in section E1. Here in alphabetical order by city name you will find the specific IAP and the non-standard alternate minimums or restrictions that apply.

Remember, alternate selection is a function of the planning process. If you must divert to your planned alternate, or for that matter an unplanned alternate, the actual minimums to be used for the approach are those specified on the IAP.

-Larry Morris
Concord, N.C.

We left out those details because the article was aimed at encouraging VFR pilots to plan for alternates at all times and for IFR pilots to consider the notion even when the weather was not too threatening. But you are correct in that some people miss the nuances of charts.


Source of Engine Woes?
In Cabin-Class Singles [Aircraft Analysis, January], at bottom of page 11, it reads:

The Lycoming-powered Mooney M20 and the Commander are two exceptions among lighter singles. In both these cases, engine failures and defects, a few maintenance-related.

The second quoted sentence appears to be missing an ending which I assume was probably meant to be something negative like: … are above average.Since I am the owner of a 1976 Commander 114, I would be most interested in those statistics. So far my low-time Lycoming 540 has presented no problems.Thank you – I have enjoyed your magazine for many years, considering it my supplemental insurance (sort of AFLAC for the air).

-Bob Kuehn
Via e-mail

You missed the two partial columns on page 11(between the charts) and combined two unrelated sentences when you were reading it, but your question still stands. In fact, we could not discern any kind of pattern among these engine failures during our analysis.


The Gender Gap
I was amused by your account of flying your Citabria from the rear seat [Editors Log, February], as I fly a 1968 7KCAB Citabria. My wife was even more amused as she has been learning to land our Citabria from the rear seat. Shes not a licensed pilot and claims she doesnt want to be. However, Im 71 years old and, though I have no known health problems, we agreed that she should be able to land the airplane in an emergency just in case.

Of course, as I have pointed out to her, if you can consistently land a tandem tail-dragger in one piece from the rear seat, youve mastered the most difficult part of flying it, so eventually she may go on to get her ticket.

Also, with reference to gender bias, My wifes instructor is a male and she has been entirely comfortable flying with him from the outset. I wouldnt dream of trying to teach her myself, as Im aware that being a pretty good pilot doesnt begin to qualify me as an effective flight instructor.

Though there are female CFIs in this area, I assured her that she would not find Tim Stewart intimidating, and I was right. Tim is a career flight instructor who has been doing it for many years and who combines a high level of competence and experience with the people skills that help to reduce stress and promote confidence. I wish there were more like him, regardless of gender.

-Richard H. Hendrickson
Ashland, Ore.

Us, too.


Head-On Doesnt Have to Be
In January, an elderly former race-car champion drove the wrong way down Interstate 70 and crashed head-on with another car in Denver that killed himself and a teenager.

Obviously, the teenager shares no blame in the head-on accident because the whole point of head-on collision safety is that heroic last-minute warnings and heroic last-second evasive maneuvering are extremely poor alternatives to preventing a head-on collision in the first place. That is why interstate highways have separate traffic lanes protected by guardrails and signs to eliminate head-on conflicts.

To assist drivers in obeying this principle, big red signs are posted at the exit ramps to warn drivers who might enter there. If vandals had removed the sign that the racer had driven past, they would face criminal penalties. If a highway maintenance contractor had temporarily removed the signs and forgotten to replace them, the contractor would have been vulnerable to civil damage claims. If the highway department had never put up the signs in the first place, then the state could challenged for failing to incorporate the safety feature. When the highway laws are obeyed on interstate highways, head-on collisions are impossible by design.

Paradoxically, the FAA refuses to incorporate safety techniques that would do a better job of keeping aircraft from having head-on collision paths. Instead, the agency relies upon voluntary compliance with technically inadequate recommendations and risk-multiplying regulations, occasionally failing electronic equipment, workload-permitting last-minute warnings from air traffic controllers and heroic last-second maneuvering by pilots to avoid midair collisions like the one over Denver on January 24.

In this case, a southbound Piper Cheyenne crashed into a northbound Cessna 172. By law, the pilots were not required to be talking to ATC, although both pilots had opted to ask for traffic following from the same controller. By law, ATC was not required to provide traffic advisories, because this service is only offered on a workload-permitting basis. By law, ATC had no responsibility for the midair collision over Denver because regulations now place 100 percent of the responsibility for collision avoidance on pilots, both IFR and VFR, flying in visual meteorological conditions.

In contrast to highway safety system design, head-on collisions are still inevitable even when all laws and regulations are obeyed.

The proven technique being ignored by the FAA is what I call the Altimeter-Compass Cruising Altitude Rule (ACCAR). This rule would have given the Denver pilots a useful tool for avoiding each other over Denver, even if they never looked out the window.

ACCAR requires a pilots imagination or a see-through sticker on the altimeter glass to mentally superimpose the north/south/east/west compass directions scale on top of the altimeter scale. The pilot then flies in a direction and at an altitude such that the compass heading angle of the 100-ft needle on the altimeter matches the magnetic heading of the aircraft.

By design, when all pilots use ACCAR for level flying as much as possible, then all pilots at every altitude are flying parallel paths that never cross – and all head-on traffic is automatically separated by 500 feet of vertical clearance. This is a huge philosophical difference compared to the hemispherical cruising altitude rules where, by design, aircraft with a compass heading of 181 degrees are required to have head-on collision paths with aircraft on a heading of 359 degrees.

ACCAR minimizes collision probability while simultaneously maximizing the time that a collision-threatening aircraft is visible to pilots in danger.

-Robert Patlovany
Westminster, Colo.


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