Tiny Errors

Minor mistakes are often forgiven, but sometimes theyre not

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All pilots have had them, those flights where you make a little mistake and it goes unnoticed for a long time.

Maybe its leaving the gear down until you get to cruise, and only then figuring out why the airspeed is so low. Perhaps you left the transponder on standby and didnt correct it until a gentle reminder crackled over the headset. And some people have been known to forget to turn off the autopilot, which makes a traffic pattern a difficult thing to fly.

The point is that minor problems rarely turn into major ones, because usually theyre caught in time. And even if theyre not caught until the airplane lands, there are few such mistakes that carry severe penalties. Occasionally, however, a seemingly minor transgression has tragic consequences.

The pilot of a Beech Debonair pilot called the Leesburg, Va., Flight Service Station at 6:12 one Tuesday morning to get the weather for a proposed flight from Martinsville, Va., to Marion, S.C., at 8 a.m. and a return flight at about 11:30. The briefer reported that high pressure dominated the region and, although there could be patches of fog and limited visibility, good weather was likely to prevail along the route for both flights.

The pilot, who held a private license with about 950 hours, filed IFR flight plans for both one-hour flights. Apparently the trip to Marion was without incident. The pilot conducted whatever business he had there and saddled up for the trip home. He departed a little later than he had planned that morning, taking off from Marion at about 1 p.m. As he climbed, he contacted Approach Control at Florence, S.C., to pick up his IFR clearance, but the controller could not find it, probably because the system had kicked it out when it was not activated shortly after the proposed departure time an hour and a half earlier.

The controller asked for the route and offered to file the flight plan immediately.

OK, sir, ah, dont bother with it. Its such a nice day Ill go VFR, the pilot responded. I wont worry about it. I appreciate your help.

The pilot climbed to 5,500 feet and proceeded on his way home.

Meanwhile, the owner of a Piper Cherokee Six 260 prepared his airplane for a flight from Midland, N.C., to Elizabeth City, N.C. One witness, a CFI who was at the airport waiting for a student to arrive, talked to the Piper owner, who said he was flying to Elizabeth City to look at a truck he was thinking of buying for his business. The witness said the owner performed a thorough preflight inspection of the airplane, but there was no record that he got a weather briefing. He boarded a passenger, started the engine without difficulty and took off at about 1:15 p.m.

The pilot, who did not have an instrument rating, had about 350 hours, including 93 in his Cherokee Six. After takeoff, he climbed into the clear blue sky and flew VFR toward his destination without calling any air traffic control facility. He leveled off at cruise at 5,500 feet.

At about 1:35, the Debonair pilot called Greensboro Approach.

Good afternoon, Greensboro. Im, uh, 10 miles north of the Sandhills VOR on the 355-degree radial, uh, level at 5,500 feet, VFR to, uh, mike tango victor, Martinsville.

Debonair five zero whiskey, squawk 0101.

0101, five zero whiskey.

Debonair five zero whiskeys radar contact and, uh, theres traffic out there. I cant tell. Your targets jumping around a good bit, uh, maybe close off your left [at] fifty five.

Radar contact was lost about 35 miles south of Greensboro. Although the controller continued to call the Beech for eight more minutes, the only reply was dead air.

Witnesses near Robbins, N.C., reported hearing a loud sound, then saw parts falling from the sky. None of the witnesses saw or heard the airplanes before the collision. Wreckage from both planes was scattered over a third of a mile of rural countryside.

A review of radar data showed seven radar hits on the Beech after it began squawking 0101. The reported altitude at each hit was 5,300 feet. A radar target identified as the Piper, which was squawking 1200, indicated it was at 5,400 feet at the exact latitude and 9 seconds of longitude north of the last Beech return.

The Piper hit the Beech broadside, with no indication that either pilot tried to take evasive action. The nose gear of the Piper struck the left tip tank of the Beech and ripped it from the airplane. The left side of the Beech showed numerous spots where the big Piper single pummeled the Debonair.

Both wings were ripped from the Piper in the violence of the crash. The engine and propeller were found nearly 1,300 feet from the main wreckage.

There was no evidence of any malfunction aboard either airplane, other than each pilots failure to spot the approaching traffic. The three people aboard the two planes were killed.

Investigators determined that the Debonair pilot appeared to be navigating via a King KN 74 RNAV unit. RNAVs work by electronically calculating user-defined waypoints using VOR and DME information. That allows the pilot to navigate direct using navaids that are not on the direct course.

The Debonairs RNAV indicated a 359 in the bearing window and about 36 in the distance window. In addition, the pilot had reported being outbound on the 355 radial from the Sandhills VOR and the destination was directly on that radial. If the pilot of the Cherokee Six flew a direct route between his departure airport and his destination, his course would have been 080 degrees.

Therefore it appears the Debonair pilot had erred in selecting his cruising altitude, while the Piper pilot was properly positioned. VFR cruising rules say that when flying on a magnetic course of 180 through 359 degrees, the proper altitude is an even thousand plus 500 feet. The fact that the two airplanes were closing at nearly right angles means that the time to spot the approaching plane would have been short indeed.

Mid-air collisions between airplanes in cruise flight are rare, but are nearly always fatal. VFR pilots need to pay strict attention to scanning for traffic, especially if theyre not using flight following or at least monitoring ATC frequencies to get a feel for the traffic in their vicinity.

One can only speculate on the impact of the Debonair pilots decision to continue the flight VFR when his IFR flight plan disappeared. Certainly he would have been at a different altitude.

But more important is the fact that the pilots mindset appears to have been that of an IFR pilot. The route apparently was a familiar one. The airport manager in Marion said the pilot usually filed an IFR flight plan when going home to Martinsville. The IFR mindset may have been a distinct disadvantage to the pilot, as he may have been used to ATC calling traffic and setting his altitude.

In some ways, VFR-only pilots can be safer when flying VFR than pilots who hold instrument ratings and sometimes fly VFR, sometimes IFR. VFR pilots often are more self-reliant, while IFR pilots get used to the services provided by the system and miss important factors without the ATC input.

As errors go, picking the wrong altitude isnt usually a serious blunder. But as this accident shows, sometimes even the Big Sky isnt big enough.


-by Ken Ibold

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