SEA98FA105

During preflight weather briefing, the pilot was briefed to expect rain showers and thunderstorms up to Level 6 (extreme) intensity along his route of flight. The pilot, whose aircraft was equipped with radar and Stormscope equipment, filed an instrument flight rules (IFR) flight plan and departed under IFR. Upon radar contact, ATC cleared the pilot direct to his destination. 21 minutes later, while flying on the direct (northwesterly) track to the destination, the aircraft entered a Level 4 thunderstorm cell. The pilot told air traffic control (ATC), '...[I] hit a pretty heavy cell here [I've] got lightning all around and picking up some hard ice.' The crew of another aircraft deviating to the north of the storm suggested the aircraft turn north to exit the weather. ATC relayed this suggestion, and the pilot replied he was turning to the north. The aircraft then entered a right turn; radar contact was lost after approximately 90 degrees of turn. 6 seconds after the time at the last radar position, the pilot radioed, '...[I'm] in a tremendous downdraft [I'm] losing altitude six thousand'. This was the last transmission received from the accident aircraft. A search for the aircraft was initiated; the aircraft wreckage was found approximately 11 1/2 hours later, approximately 1 1/2 miles south of the last radar position. Logbooks recovered from the wreckage indicated the pilot was not current for IFR flight.

History of flight

On June 18, 1998, approximately 2207 mountain daylight time, radio and radar contact was lost with N88JH, a Cessna 340 registered to America West Communications of Ritzville, Washington, while on a 14 CFR 91 business flight from Gallatin Field, Bozeman, Montana, to Glacier Park International Airport, Kalispell, Montana. The flight was on an instrument flight rules (IFR) flight plan from Bozeman to Kalispell at the time of the disappearance. The wreckage of N88JH was located by search and rescue forces on the morning of June 19, 1998, approximately 8 nautical miles southeast of Lincoln, Montana. The aircraft was found to be destroyed, and the private pilot-in-command, who owned America West Communications and was the airplane's sole occupant, was found to have received fatal injuries. Visual meteorological conditions were reported at Helena, Montana (approximately 30 miles southeast of the accident site) at 2156 on June 18; however, the pilot reported to air traffic controllers that he had encountered a thunderstorm just prior to the loss of contact.

Air traffic control (ATC) information furnished by the FAA indicated that the pilot contacted the FAA automated flight service station (AFSS) in Great Falls, Montana, by telephone from Bozeman approximately 2051 and again approximately 2114 on the evening of the accident. In the first contact, the pilot requested the current weather in Kalispell and eastern Washington between Moses Lake and Spokane (NOTE: Ritzville, where the pilot indicated the aircraft was based when he filed his IFR flight plan for the accident flight, is located approximately midway between Moses Lake and Spokane.) The briefer gave hourly observations for Bozeman and Kalispell in Montana and Moses Lake, Ephrata, Wenatchee and Spokane in Washington; all stations were reporting visual flight rules (VFR) conditions, with cumulonimbus distant in all quadrants at Kalispell. The pilot then asked if "this low front or this little front that was coming across" would be dissipating by morning; the briefer replied that marginal VFR conditions were forecast for the flight area, with no improvement forecast until late Friday (June 19) or early Saturday (June 20), approximately 24 to 36 hours after the time of the call.

The pilot then asked for any pilot reports (PIREPs) or information on tops between Bozeman and Spokane; he was provided forecast cumulonimbus tops ranging from flight level (FL) 180 to FL 320 with associated shower activity and turbulence, and bases of a scattered to broken layer at 13,000 feet (with top of the layer at 14,000 feet) in Montana and Idaho. The pilot then asked, "but right now [K]alispell's open whats youre saying [sic]". He was told that it was open "right now" and was given the radar picture showing most echo activity south of Missoula and northwest of Great Falls, with significant light to moderate (but possibly heavy to very heavy) cells or precipitation through Missoula, Montana. The pilot replied, "ok well [I'm] in a three forty [I] may [I] may [sic] elect to go to [K]alispell [IFR] tonight". The briefer reiterated that the flight would cross significant shower activity and described Doppler radar decibel levels as reaching up to 57, level 6 and above in intensity, extreme. The pilot stated, "[I] know". The pilot then asked if the weather was predicted to "hang through tomorrow", and was told again to expect it through Saturday morning with an improving trend for a few days after that. The pilot then stated he would think it over and call back if he wanted to file a flight plan, and the briefer told the pilot again to expect the shower activity to continue for the next 24 to 36 hours.

In the 2114 telephone contact with Great Falls AFSS, the pilot stated he was at Bozeman and wanted to go IFR to Kalispell in about 15 minutes. The Great Falls AFSS briefer confirmed the pilot's destination as Glacier Park International, and his intention to fly IFR. The pilot said he had called a few minutes ago and that "they said it was fairly clear up there." The briefer told the pilot that Kalispell was reporting cumulonimbus and showers distant northwest through northeast, and that the biggest areas of precipitation en route would be south of Missoula. The pilot replied that he was going direct from Bozeman to Kalispell, and that he could see "from here to [G]reat [F]alls". The briefer stated:

yeah its uh its not bad at all going in that direction like [I] say just south and a little southeast of [M]issoula theres some light to moderate precipitation echoes uh you might keep your eyes open for that um other than that uh there is some uh cumulonimbus pretty much over the entire route but nothing too terribly bad [I] dont believe there are any convective sigmets not at this time and no sigmets...

The briefer then gave the Kalispell terminal forecast, which was for VFR conditions with occasional light rain showers and occasional ceiling of 4,000 feet broken. The pilot then filed an IFR flight plan from Bozeman to Kalispell, giving the following data: cruise altitude 14,000 feet, proposed time of departure approximately 2130, 1 hour estimated time enroute at a true airspeed of 180 knots, and 5 hours fuel on board.

At 2128, the pilot called the Salt Lake City, Utah, Air Route Traffic Control Center (ARTCC) by radio while on the ground at Bozeman, and requested and received his IFR clearance to Kalispell. The clearance was to Glacier Park International via the V343 Federal airway to the Drummond VOR, then direct, at 14,000 feet.

At 2142, the pilot called Salt Lake ARTCC about 20 miles northwest of Bozeman at 14,000 feet (Gallatin Field, the departure airport, is non-towered), and radar contact with the aircraft was established. ATC then cleared the flight direct to Glacier Park International. Approximately 2144, the pilot requested and received a clearance to climb to 16,000 feet. At 2153, the pilot called Salt Lake ARTCC asking how his track looked to Kalispell, and was told that it looked good.

The transcript of the pilot's communications with ATC indicated that at 2205:20, the pilot told the Salt Lake ARTCC controller, "...[I] hit a pretty heavy cell here [I]'ve got lightning all around and picking up some hard ice." The Salt Lake ARTCC controller then told the pilot that another aircraft approximately 10 to 12 miles north of his position, Alpine 5013, was going around the north end of the cell at 11,000 feet. The crew of Alpine 5013 then told the Salt Lake controller to tell N88JH to divert directly north in order to exit the weather. The Salt Lake controller told N88JH, "...suggestion is to uh turn to the north to avoid the weather." The pilot replied, "uh give me a steer", and the controller said, "uh heading three six zero", at 2206:14. The pilot replied, "roger turning three six zero" at 2206:17. The crew of Alpine 5013 subsequently described the storm as "heavy to extreme" on the sector frequency, reporting that "there's a lot of lightning out here just to the left of us."

ATC radar data showed N88JH on a generally northwesterly course at approximately 16,000 feet at an average ground speed of 200 knots until the last secondary radar return at 2206:35 at 15,900 feet. Two correlated primary radar positions indicating a right turn of approximately 90 degrees were then depicted, the first at 2206:47 and the second at 2206:59, before loss of radar contact. At 2207:05, the pilot told Salt Lake ARTCC, "[I]'m in a tremendous downdraft [I]'m losing altitude six thousand." This was the last reported transmission from the accident aircraft. The controller cleared the pilot to descend at pilot's discretion to 12,000 feet at 2207:18, without response. The crash site was approximately 1 1/2 nautical miles south of the last (2206:59) radar position.

The accident occurred at the end of evening civil twilight, during dark night conditions, a