CC Log: Profile Of A Near Midair Collision

I turned inbound on the 45-degree entry leg with the airport in sight and no known traffic. Directly below me was downtown Long Beach, and the once-productive oil wells of Signal Hill were just ahead. I extended the gear to help slow the slick Aerostar and eased the nose over just a little to bleed away some altitude.

At the same time, I heard the controller comment, "Aerostar inbound, we have a Duchess outbound on the 45 slightly to your left."

The city below was rapidly turning to a muddle of houses and small businesses, every pilot's nightmare scenario in the event of an engine failure. Traffic was heavy, and Long Beach was working three runways---30, the 2-mile-long airline runway, plus 25L and 25R, normally utilized by light plane traffic.

Suddenly, out of the corner of my eye, I sensed movement where there shouldn't have been any. It was the Duchess coming head-on right toward me, its T-tail headed directly at my left wing.

There was no time to react, much less to evade. I caught an instantaneous, blurred image of two pilots looking down at the instrument panel. The pilot in the left seat may have been wearing an instrument hood.

The Duchess was there and gone so fast, I wasn't sure what had just happened. The Beech flashed by below me, and I felt the hard bump of his wake.

I was stunned by what had almost happened. If the Duchess had been a foot or two higher or I had been a foot lower, both airplanes would have been turned into aviation confetti, raining down on the city of Long Beach. 

The point of the story isn't about placing blame. I believed I was where I should have been, and I'm sure the Duchess pilot felt he was doing everything right, as well.

Unfortunately, assessing cause and effect can be far more complex than what meets the eye. Pretty obviously, the most dangerous midair threat, and the one that almost bit me, is one that comes from straight ahead, as there is precious little time to see and avoid.

Military pilots must sometimes deal with astonishing closing rates of 1,000 knots or more. That's roughly a mile every 3.5 seconds. In other words, if a pair of F-15s broke out cloud banks a mile apart on a collision course, they'd have just four seconds to see and avoid.

To no one's surprise, the military was primary in developing techniques for efficient scanning. During World War II, when literally hundreds of airplanes often filled the skies over Europe, finding and identifying aircraft as friend or foe became life-or-death factors. The pilot who could spot and identify their adversary quickest had a distinct advantage over the enemy. The catchphrase for WWII fighter pilots was, "First sight, first shot, first kill."

For better or worse, most of us don't fly F-15s, so our potential head-on closure rates shouldn't exceed 350 knots.

If the head-on risk represents the most instantaneous danger, at least the view straight ahead usually isn't blocked by airframe structures, even if it is the riskiest. Windshields are usually free of blocking members, so visibility is rarely limited straight ahead.

Looking aft isn't so easy. Military aircraft often have bubble canopies that allow vision in every direction. Unfortunately, there are few personal airplanes that offer rearview mirrors; even when there's a view of the aft, it usually includes the back seats and not much else. When rear windows are even available, they're about the size of mail slots. 

Theoretically, this leaves several possible threat zones: directly above, below, to the right or left sides, or the rear.

There's not much you can do about possible overtakes from the rear. That was exactly the scenario that was attributed as the probable cause of the midair between a PSA 727 and a Cessna Skyhawk on approach to Lindbergh Field in San Diego in 1978.

Both airplanes were approaching the airport from the same direction but at different altitudes. The Cessna was well ahead of the PSA flight and was called as traffic. PSA spotted the Cessna ahead, below and slightly to his right. Later in the approach, the controller called out the Cessna again, and PSA responded that, "We had him. We must have passed him."

A few seconds later, the 727 struck the Cessna from above, and both airplanes crashed into houses below. There were no survivors among the 144 people aboard the two aircraft.

Clearing airspace below your airplane is extremely difficult since very few aircraft have any visibility looking straight down. Some military aircraft have a pronounced advantage because they can maneuver in three dimensions as part of normal operation, and that ability sometimes isn't understood by many non-pilot witnesses on the ground.

In another accident, this one above the Mojave Desert outside Los Angeles, a U.S. Marine F4 Phantom fighter was routing toward an airbase in Southern California. An airliner was descending toward LAX in the same area.

Witnesses on the ground claimed the F4 was "stunting" as it flew overhead. The two airplanes collided, and the F4 apparently took off the tail of the airliner. The pilot of the F4 and everyone aboard the airliner were killed, but the F-4 backseater was able to eject safely.

At the inquiry, the survivor explained that the pilot had executed a quick 360-degree roll to clear the airspace below, though that maneuver had nothing to do with the accident. Highly responsive military aircraft can and do fly maneuvers that few civilian aircraft (or pilots) can perform.

Back in the 1980s, there was an airplane offered with an unusual aid to downstairs visibility. Partenavia of Italy built an unusual twin called the P68 Observer that offered a forward cockpit constructed primarily of clear Plexiglas. Sales weren't exactly staggering, but the Observer did provide a welcome view of the airspace below and around the aircraft. I delivered a half-dozen of these from the factory in Naples, Italy, to dealers in Florida and California. The models were popular for powerline inspection, police traffic and crime monitoring, wildlife management and other jobs that relied on a high station. The second provided a welcome hedge against an engine failure over a heavily populated area.

Considerations of wing placement also may make the image to top or bottom difficult or impractical. In general aviation circles, the debate has raged for years, often devolving to the type of aircraft a pilot trained in. High-wings are preferred in many cases because of their view of the ground, whereas low-wings often get the nod because of their better vision of other aircraft in the pattern.

The process of scanning for other traffic often isn't well understood because the subject isn't really explored in civilian flight schools. Pilots are often told to "keep your head on a swivel and your eyes open," a fairly obvious precaution for all pilots all the time.

There's a more logical method of scanning for traffic, however, and that's by segments. If you merely sweep your eyes across the horizon without allowing them to focus properly, you won't stand much chance of spotting anything but sky and cloud. For that reason, a more organized scan might consist of checking the surrounding airspace in 45-degree chunks, spending a few seconds to allow your eye to focus on the image, then checking the most dangerous quadrant---straight ahead---then moving on to the next quadrant.

I know a pilot who nearly failed his commercial check ride because he stared pretty much straight ahead the whole time and never bothered to see if something might be gaining on him from another direction. Back on the ground, the examiner, a former military fighter pilot, ripped into the pilot and began to write a pink slip, then stopped and insisted the two fly a portion of the test again. They did, and I passed the second time. PP