In January, an elderly former racecar 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 even put up the signs in the first place, then the state could be 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 FAA 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, 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 pilot's imagination or a see-through sticker on the altimeter glass, to mentally superimpose a 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
Other letter writer's responses to the above letter in a subsequent issues of Aviation Safety.
As a charter pilot in the Chesapeake Bay area, I frequent the coastal airfields of NJ, MD, VA, and NC, nearly always under ATC control. Recently I was flying IFR in clear weather approaching my landing airfield. ATC cleared me to 3,000 feet. Jumpin' Jeosophat! Suddenly a westbound VFR single appeared at my altitude. Thankfully, it only took a 2 g pull up to avoid the airplane this time.
Why do pilots always fly at 3,000 feet, regardless of whether they're flying north, south, west or east, no matter what the weather? I know, VFR cruising rules don't apply unless you are operating above 3,000 feet, which really helps you maintain cloud clearances when clouds exist below 4,000 ft. But on a clear day, why not 2,700 feet? How much protection against the dreaded engine failure do you lose?
This situation happens to me pretty often, although I can usually avoid the 2 g maneuver with increased visual vigilance. What I haven't tried yet is turning down the 3,000-ft assignment from ATC.
Although Robert's solution may not be optimal for all, in my opinion it's sure better than the 3,000-ft danger zone that has been manufactured by the FARs in league with the brainless 3,000-ft cruisers.
Any suggestions?
Bruce Sheppard
Easton, Md.
Just read Robert Patlovany's letter of recommendation for an "ACCAR" altitude separation system and really liked it. As one who frequently flies a course of 180 or 360, give or take two degrees, I always think about that head on traffic at my altitude. My solution (at least until the FAA gets it together) is to fly 185 or 005 to allow a little elbow room for the other guy.
I continue this course, watching my GPS set for my destination or way point, until I have a good 10 degrees off the north/south heading and then turn to the direct course. This five degrees off direct heading is always just a bit right of course, which in all the civilized world, save a few of our friends, is the direction for all sailing an motorized traffic to break in the event of an imminent head-on.
This procedure only adds a few miles to the overall trip but gives me many miles of comfort.
Jack Gibbert
Texarkana, TX