# NTSB SEA96FA024: Beech C24R, N3729T, Bozeman, MT, November 25, 1995 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: November 25, 1995, 15:54 local (22:54 UTC) - Place: Bozeman, MT - Coordinates: 45.769535, -110.930084 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=45.7695&lon=-110.9301&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed, report November 11, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 42265 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA96FA024 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42265/pdf - Page: https://openairdocs.org/ntsb/SEA96FA024 ## Probable cause failure of the pilot to follow the specified approach track (proper IFR procedure), and his associated failure to maintain altitude or clearance from mountainous terrain. Factors relating to the accident were: the pilot's failure to abide by the aircraft owner's (dispatch) procedures, heavy snowfall, mountainous terrain, and possible pilot impairment from altitude hypoxia. ## Analysis The flight was on an instrument flight rules (IFR) flight plan and had been cleared by air traffic control (ATC) for an instrument landing system (ILS) approach. The aircraft owner, along with the flight instructor, who completed the pilot's instrument training as well as his checkout in the accident aircraft, stated that they had instructed the pilot not to fly the accident aircraft in IFR conditions. The airplane was flown at an altitude of 13,000 feet for 32 minutes before commencing the approach, and it was not equipped with supplemental oxygen or cabin pressurization. The pilot failed to follow the specified ground track for the approach, and the airplane impacted mountainous terrain about 13-1/2 nautical miles north-northeast of the airport in heavy snow conditions. The accident site was approximately 15-1/2 nautical miles beyond the point where a turn onto the localizer was specified on the approach procedure. The airport did not have a control tower or approach control radar, and the airplane was not in radar contact with ATC at the time of the accident. A hunter near the accident site saw an airplane fly over his position at low altitude in heavy snowfall. He heard a loud metallic 'clank' about 20 to 30 seconds after the airplane disappeared from his view. Also, he noted the time on his watch, which corresponded to the estimated time of the accident. ## Factual narrative HISTORY OF FLIGHT On November 25, 1995, at 1554 mountain standard time, a Beech C24R, N3729T, registered to First National Insurance of Dillon, Montana, was substantially damaged when it collided with mountainous terrain approximately 13 nautical miles north-northeast of Gallatin Field, Bozeman, Montana. Both occupants (the private pilot and a passenger) were fatally injured. The 14 CFR 91 flight had originated at Troutdale, Oregon, with a stop in Lewiston, Idaho, and was on an instrument flight rules (IFR) flight plan from Lewiston to Bozeman. The flight had been cleared by Salt Lake Air Route Traffic Control Center (ARTCC) for an instrument landing system (ILS) approach to runway 12 at Bozeman. Instrument meteorological conditions prevailed in the accident area. FAA air traffic control (ATC) records indicated that the pilot received a weather briefing from the automated flight service station (AFSS) at McMinnville, Oregon, and departed Troutdale on an IFR flight plan, landing at Lewiston and remaining on the ground there from 1232 to 1258 Pacific standard time. According to these records, the flight was cleared to an altitude of 13,000 feet out of Lewiston and cruised at an altitude between 11,000 and 13,000 feet for the entire flight from Lewiston, maintaining 13,000 feet for the last 32 minutes prior to arriving at THESE intersection (284 degrees magnetic/19 nautical miles from the Bozeman VOR/DME, an initial approach fix (IAF) for the ILS approach.) The aircraft was not equipped with cabin pressurization or supplemental oxygen. Communications transcripts documented a number of irregularities in the pilot's radio communications during flight at these altitudes, including incorrect altimeter setting readback (1429:41), confusing/stumbling over his call sign (1429:41 and 1514:33), stumbling over airway assignment/altitude options given by the controller (1508:10), and failing to respond to a frequency handoff call for over 30 seconds until the controller's third attempt at contact (1513:53 to 1514:27.) The communications transcript also indicated that at one point (1504:36), a Spokane approach controller, handing the flight off to Salt Lake ARTCC, relayed to the Salt Lake controller that the airplane was "a negative oxygen equipped" and gave the opinion that the pilot was "not all that good at navigating", and asked the Salt Lake controller to "make sure he comes our [sic] the other side." During this exchange, the pilot was maintaining an altitude block from 11,000 to 13,000 feet due to icing conditions at 11,000 feet, according to the transcript. According to the FAA ATC records, the pilot approached THESE from the northwest along the V343 federal airway. He reported at THESE intersection and was cleared for the approach at approximately 1544. The last National Track Analysis Program (NTAP) recorded radar position on the aircraft was approximately 6 nautical miles west-northwest of THESE at 13,100 feet at 1541:25. According to the FAA ATC communications transcript, the Salt Lake ARTCC controller informed the pilot that radar contact had been lost at 1546:14. The ILS runway 12 instrument approach procedure for Bozeman specifies that from THESE IAF, the approach is flown on the 060 degree radial outbound from the Whitehall VORTAC (approximately 43 nautical miles west of Bozeman) for 5.1 nautical miles at an altitude of 7,300 feet. A right turn is then made onto the localizer course of 118 degrees magnetic. According to the FAA ATC communication transcript, at 1546:24, the Salt Lake controller asked the pilot of N3729T if he was established on the localizer yet; the pilot replied that he was not. At 1549:41, the controller again asked the pilot if he was on the localizer yet. The pilot replied that he was not but that he expected to be established in "approximately four minutes." At 1555:54, the controller asked a third time if N3729T was on the localizer, this time without reply. A tape recording of 121.5 MHz from the Great Falls, Montana AFSS recorded an emergency locator transmitter (ELT) activation at 1553:50. This recording indicated that the source of the ELT signal was subsequently localized to a magnetic bearing between approximately 005 and 015 degrees from Gallatin Field. Several aircraft in flight also reported to the Salt Lake controller that they were receiving an ELT signal at this time. A hunter in the mountains near the accident site observed a small single-engine aircraft flying "almost due east", 150 to 200 feet south of his position and at an altitude the hunter estimated to be 400 to 500 feet above him. He stated that it was snowing heavily at the time with a visibility he estimated at 400 to 500 feet. He stated that he observed the aircraft for about 10 seconds and that it appeared to be flying level or slightly climbing. He reported that 20 to 30 seconds after the airplane disappeared from view, he heard a loud metallic "clank." He stated that he checked his watch 15 to 20 seconds after hearing the noise and that his watch read 3:57 PM. He stated that the airplane's engine sounded like it was running smoothly during the time he observed the airplane. The aircraft wreckage was located by an Air Force rescue helicopter on the morning of November 26. It was in mountainous terrain about 13.5 nautical miles north-northeast of Gallatin Field at approximately the 7,800 foot level on a 30 to 35 degree slope. Both occupants were subsequently found dead at the scene. The accident site was offset approximately 2 nautical miles to the right of the extended 060 degree radial of Whitehall VORTAC and was approximately 21 nautical miles east-northeast of THESE. The accident occurred during the hours of daylight at 45 degrees 59.78 minutes North and 111 degrees 2.46 minutes West. PERSONNEL INFORMATION According to a copy of an FAA airman certificate application dated October 27, 1995, which was recovered from the aircraft wreckage, the pilot had approximately 150 hours total pilot time including 42 hours of instrument time and 1 hour on an AST-300 simulator. The FAA application indicated that the pilot had received his private pilot certificate on August 22, 1995. He successfully completed a practical test for an instrument rating in a PA-28-161 airplane at Billings, Montana, on October 28, 1995. The certificated flight instructor (CFI) who finished the accident pilot's instrument training in Bozeman stated to investigators during a post-accident interview on November 27, 1995 that the pilot had practiced the Bozeman ILS runway 12 approach from THESE several times during his instrument training, and characterized the pilot's performance and proficiency during instrument training as well above average. The FAA designated examiner who administered the instrument practical test to the accident pilot described the pilot's performance on the test as "above average proficiency...considering his level of experience" in a letter to the NTSB investigator dated December 6, 1995. The CFI who had finished the accident pilot's instrument flight training stated that he had flown two checkout rides, totaling 2.3 hours, in the C24R with the accident pilot on the Monday and Tuesday before the accident (November 20 and 21) and that the pilot departed on a cross-country flight to Oregon in the C24R immediately afterward, on the afternoon of the 21st. The aircraft owner and the CFI both stated in post-accident interviews that they instructed the pilot not to fly the aircraft in instrument conditions. The aircraft owner repeated this statement in a written report of the accident, stating that he and the CFI agreed that this would be a condition of use of the aircraft for the accident pilot. The CFI stated during his interview that he provided only a basic aircraft checkout to the pilot, consisting of basic air work, emergency procedures and visual traffic patterns; and that he deliberately gave the p ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, approach - iaf to faf/outer marker (ifr) - dispatch procedures - not followed, pilot in command (contributing factor) - weather condition - low ceiling (contributing factor) - weather condition - snow (contributing factor) - ifr procedure - not followed, pilot in command (cause) - physical impairment(anoxia/hypoxia), pilot in command (contributing factor) - terrain condition - mountainous/hilly (contributing factor) - altitude/clearance - not maintained, pilot in command (cause) - radar,approach/departure - not installed ## Aircraft - Registration: [N3729T](https://openairdocs.org/deregistered/N3729T-2015-05-19), registration cancelled 2015-05-19, S/N MC-737, built 1980 (OpenAirDocs) - Reported make and model: Beech C24R - Registry model: [Beech C24R](https://openairdocs.org/model/beech-c24r) (registry code 1151254) (OpenAirDocs) - Registry engine: [Lycoming I0360 SER A&C](https://openairdocs.org/engine/lycoming-i0360-ser-a-c) (registry code 41511, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: MC-737 - Airframe hours: 3311 - Engines: Lycoming IO-360-A1B6 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: First National Insurance - Airworthiness certificate: Standard, Normal - Last inspection: Annual, November 7, 1994, 40 hours before - Departed: LWS, LEWISTON, ID - Destination: BZN - Flight plan: IFR - Airport: BZN, Gallatin Field, runway 12 ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 21; private; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 158 total, 9 in this make and model, 119 as pilot in command, 11 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day - Wind: 100° at 7 knots - Temperature: 39 °F, dew point 37 °F - Altimeter: 29.00 inHg - Observed at: BZN, 14 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19951125038379A](https://openairdocs.org/incident/19951125038379A), Nov 25, 1995: Beech C24R, Bozeman, MT, Substantial damage, 2 fatal. Collided with mountainside in heavy snowfall. Pilots speech and actions poor. Had been at FL130. No oxygen system. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.