Probable Cause #8: Night Over Water

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On a clear night with a full moon, a visual descent to the airport turned into a splashdown on a poorly flown instrument approach.

This article originally appeared in Aviation Safety, March 2004.

Probable Cause

Night flight brings with it a number of threatening elements. From invisible weather to pilot fatigue to visual illusions, night brings with it challenges that don't seem daunting until you are alone in the darkness.

In some countries, an instrument rating is required to fly at night. The wisdom of that requirement is up for debate, but instrument proficiency is hardly a guarantee that the pilot won't rely on outside visual cues at a time when they're anything but reliable.

An example of how you can run into trouble is the sad case involving the owner of a Piper Arrow who was flying from his home in Cleveland to Bridgeport, Conn. The pilot left Cleveland at about 1530 on an IFR flight plan. The flight was uneventful until he began his approach to his destination.

At 1753 he contacted the Bridgeport Tower and said he was nine miles northwest and inbound for landing. The controller told him to report a right base for Runway 29, which the pilot acknowledged. A few minutes later, the pilot reported he had lost sight of the airport.

He said he was directly east of the airport, over the shoreline, but the Tower controller was unable to spot the airplane. The controller turned the runway lights up to maximum, and a few minutes later the pilot said, "I believe I see the airport now." He thought he was due south of it.

The Tower controller was unable to see the airplane, so he instructed the pilot to contact New York Approach for vectors. New York issued vectors for the VOR Runway 29 instrument approach, and at 1807 the pilot reported he was established on the approach and descending to 1500.

Weather at the time included clear skies and 10 miles visibility. The wind was from 300 at 13 knots, gusting to 17. The moon was 99 percent full.

The pilot was handed off to the Tower, and he reported he was abeam the final approach fix inbound on the instrument approach. The Tower controller did not have the airplane in sight, but he cleared the pilot to land.

Radar data showed the airplane tracked about 300 degrees -- the final approach course was 275 degrees -- and during the last two minutes showed a descent rate of about 1,300 feet per minute. The last radar contact showed the airplane about three-quarters of a mile north of the final approach fix at an altitude of 200 feet. The decision altitude for the approach was 380 feet.

The Puzzling Pieces

The pilot held a commercial certificate with ratings for multi-engine and seaplanes. He also held a flight instructor certificate. On his last medical application, six months earlier, he reported 1,520 hours total time. He told his insurance company seven months earlier that he had 1,000 hours in make and model.

The airplane came to rest intact and upright on the ocean floor in 38 feet of water. Examination of the wreckage found no indications of pre-accident mechanical problems.

The VOR was set to the correct frequency and the OBS was set to the final approach course. Investigators attempted to recover data from the Garmin 155 GPS that was on board, but the unit had been submerged in salt water for five days and no data could be extracted.

Another pilot who departed Bridgeport on an hour-long local flight shortly before the accident pilot's arrival said he could easily see Bridgeport and the runway end identifier lights for Runway 29. He reported no obstructions to visibility throughout the duration of his flight.

There is no doubt that visual illusions created by distant lights or the reflection of strong moonlight off water can be disorienting. That's one reason why instrument skills are helpful at assisting with VFR flight.

Yet skills are only useful if you put them to use. Despite the navigational aid of a GPS and a VOR, the pilot was unable to find the airport visually at first, and then he failed at making the proper instrument approach into his destination.

The dynamics within the cockpit at the time of the accident are open to speculation, but evidence suggests he did not trust his instruments enough to counter the siren song of the visual illusions.


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