SEA93LA168
1993-08-01 · EPHRATA, Washington, United States · Serious · 1 aircraft · Status: Completed
Airport EPH
Aircraft involved
Probable cause & findings
INADEQUATE VISUAL LOOKOUT BY BOTH PILOTS, RESULTING IN THEIR FAILURE TO SEE-AND-AVOID EACH OTHER'S AIRCRAFT. A FACTOR RELATED TO THE ACCIDENT WAS: FAILURE OF THE GRUMMAN 164B PILOT TO ADEQUATELY MONITOR THE UNICOM FREQUENCY.
Factual narrative
On August 1, 1993, at 0950 hours Pacific daylight time, a Cessna A150L, N5958J, and a Grumman 164B, N8407K, collided over the threshold on Runway 2, at the Ephrata Municipal Airport, Ephrata, Washington. Visual meteorological conditions prevailed at the time and no flight plan was filed by either pilot. Both airplanes were destroyed and the student pilot in the Cessna, and the certificated commercial pilot in the Grumman were seriously injured. Both flights originated at Ephrata for local flights. The student pilot was practicing touch-and-go landings, while the pilot in the Grumman was returning from an aerial application flight that had originated from Ephrata at 0915 hours. The student pilot reported that he had performed one touch-and-go without incident. After take off, the pilot announced his position on downwind, base and final. While on the base leg, the pilot stated that he saw the spray plane and thought that it was taking off from runway 11. The student did not see the spray plane again until just before the collision. The student reported that he did not hear any radio transmissions from the spray plane. The spray plane pilot reported that after the completion of an aerial application flight, if there was any herbicide left over, he had an agreement with the airport authority that he would spray next to the runway for weed control. The pilot reported that as he approached the airport from the north, he announced on 122.8 that he would be spraying on the west side of runway 20 and on runway 11. The spraying altitude was approximately 50 feet above ground level. The pilot reported that he did not see or hear the student pilot in the pattern. The collision occurred over the threshold of runway 2 at an elevation of approximately 50 to 75 feet. The UNICOM operator reported that she heard the student pilot announce his position while in the pattern, however, she did not hear the spray plane pilot at any time. A witness, who is a certificated flight instructor, was in an airplane in the run-up area for runway 2 at the time of the accident. The flight instructor reported that he heard the student pilot in the pattern make clear and accurate position announcements. The flight instructor first observed the spray plane when it was approximately 100 feet above ground level and flying almost directly over his airplane. At no time did the flight instructor hear position announcements or intentions from the spray plane. A MID-AIR COLLISION OCCURRED AT AN ALTITUDE OF 50 TO 75 FT OVER THE THRESHOLD OF RUNWAY 2, WHICH INVOLVED A CESSNA 150, N5958J, & A GRUMMAN 164B, N8407K. THE CESSNA PILOT WAS A SOLO STUDENT, PRACTICING TOUCH-AND-GO LANDINGS. HE WAS ON FINAL APPROACH TO RUNWAY 2. THE GRUMMAN PILOT HAD ENTERED THE AIRPORT ENVIRONMENT FROM THE NORTH & WAS SPRAYING A HERBICIDE ON THE EDGE OF THE RUNWAYS FOR WEED CONTROL. WHILE IN THE PATTERN, THE STUDENT SAW THE GRUMMAN & THOUGHT IT WAS DEPARTING FROM RUNWAY 11. AFTER THAT, HE DID NOT SEE THE GRUMMAN. THE GRUMMAN PILOT STATED THAT AS HE APPROACHED THE AIRPORT, HE ANNOUNCED THAT HE WOULD BE SPRAYING THE WEST SIDE OF RUNWAY 20 & ON RUNWAY 11. HOWEVER, NEITHER THE STUDENT NOR 2 WITNESSES, WHO WERE MONITORING THE UNICOM FREQUENCY, HEARD THE GRUMMAN PILOT ANNOUNCE HIS INTENTIONS. THE GRUMMAN PILOT SAID THAT HE NEITHER SAW NOR HEARD THE CESSNA IN THE TRAFFIC PATTERN, BUT THE 2 WITNESSES VERIFIED THAT THE STUDENT HAD ANNOUNCED HIS POSITION AROUND THE PATTERN. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1993_SEA93LA168.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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