Grumman G-21A accident at Near Haines, Alaska, 20 Aug 1958

Accident narrative

On August 20, 1958, at approximately 1525 hours P.S.T., an Alaska Coastal Airlines Grumman G-21A amphibian descended into the glassy water of Lynn Canal near Eldred Rock, 65 miles north-northwest of Juneau, Alaska. The aircraft struck the water in a cruising configuration from an established altitude of approximately 200 feet. Of the nine people aboard, the pilot and six passengers were seriously injured; one passenger died four days later. The aircraft received major impact damage, sank, and was not recovered.

### The flight

Flight 38 was a scheduled trip from Juneau to Haines, Alaska, with a planned flag stop at Briget Cove on the return. The amphibian, identified in carrier records as N77C, was normally used as a freighter. It was fitted with bench-type bucket seats along the right side and a rearward-facing seat attached to the left forward bulkhead. The pilot occupied the left seat, a passenger occupied the copilot's seat (as authorized by a Civil Aeronautics Administration deviation), and seven passengers rode in the cabin.

The aircraft carried 228 pounds of baggage and 28 pounds of cargo and mail. Its takeoff gross weight was 6,888 pounds, well under the maximum allowable 8,920 pounds, and the center of gravity was within limits. The fuel load provided a reserve of approximately one hour.

The pilot, John B. Dawson, had accumulated 7,500 flying hours, including 5,000 hours in this type of operation and over 3,500 hours in Grumman G-21 aircraft. He had been off duty for 19 hours before his shift, reported a normal amount of sleep, and had completed a brief morning flight without issue.

### Sequence of events

The flight departed the Juneau seaplane base, estimating 35 minutes en route to Haines. The pilot made normal position reports at Eagle River at 1503 and Berners Bay.

Weather along the route was adequate for visual flight rules (VFR) operation, featuring scattered patches of low stratus and fog, and a light drizzle. In-flight visibility was reported as two to three miles. Sea conditions were calm, and a pilot who preceded Flight 38 noted the water of Lynn Canal was very "glassy."

The pilot stated he had planned to inspect Briget Cove from the air on the way to Haines to check the water landing area for obstructions. En route, he became confused and flew up an inlet he thought was Briget Cove, circling to locate the Haines airport. A passenger recognized the area as Berners Bay, midway between Juneau and Haines and well to the right of the planned course.

Realizing he was short of his destination, the pilot left Berners Bay, returned to Lynn Canal, and passed between Eldred Rock and Sullivan Island. His last recollection before impact was reaching for the microphone to report passing Eldred Rock.

Personnel at the U.S. Coast Guard Lighthouse Station at Eldred Rock observed the aircraft flying at 150 to 200 feet. About 3-3/4 miles northwest of the station, the airplane began a slow descent as if to land, though witnesses agreed there was no change in engine sound. Nearing the water, the aircraft began a slight bank to the right and struck the surface in a slightly nose-down, right-wing-down attitude.

The amphibian cartwheeled, tearing both engines from their nacelles and shearing off the left wing. The wreckage came to rest nearly right side up. The pilot, whose vision was temporarily impaired by injury, crawled across the top of the cabin and opened the main door. He and a Coast Guardsman rescued all passengers before the aircraft sank in 150 feet of water.

### What the investigation found

Passengers stated the engines sounded normal before impact, and the pilot reported that the flight controls responded normally at all times. The Board explored the possibility of carbon monoxide poisoning, but company inspection records and inflight tests revealed no danger of contamination. The Board also ruled out pilot fatigue.

The aircraft was operating under a CAA deviation that permitted Alaskan flights below 500 feet provided an emergency landing could be made at any time. The pilot was familiar with company procedures for glassy water, which required maintaining visual reference to a shoreline.

The Board noted that the smooth, stable air would have permitted the trimmed airplane to fly a straight course without control action. A gradual descent could have resulted from the pressure of the pilot's arm or body against the elevator control, but the Board found no evidence to substantiate this.

At the time of the accident, the aircraft was flying approximately 200 feet above the water, with a 913-foot island half a mile to the left. Directly ahead, the glassy water blended with the low overcast sky, obscuring any definite horizon. The Board believed the island was the pilot's only visual reference in that immediate area.

The pilot testified that he "blanked out" and could not recall portions of the flight immediately preceding the impact. A post-accident physical examination revealed no medical issues, though attending physicians advised him to discontinue flying as a pilot, and the company released him indefinitely.

The Board concluded that the pilot was not sufficiently attentive to his instruments and failed to fully utilize the limited outside visual references to fix the aircraft's pitch attitude. The Board believed the pilot was subject to a fixation induced by the monotony of a familiar route and preoccupation with searching for visual references. It considered it probable that he was visually scanning the shores through the side window for a geographic reference point. During this preoccupation, the lack of a discernible horizon and the glassy water prevented a sufficiently arrestive reference to alert him to the nose-low attitude and dangerous proximity to the water.

### Probable cause

The Board determined the probable cause of this accident was "the failure of the pilot to maintain control of his aircraft at a safe altitude during marginal visual flight conditions. A contributing factor was a glassy surface which caused the pilot to misjudge the height above the water."