Accident Details
Probable Cause and Findings
The pilot's failure to maintain adequate altitude over, or clearance with, mountainous terrain during night visual flight rules flight. Factors included night lighting conditions and mountainous terrain.
Aircraft Information
Registered Owner (Historical)
Analysis
HISTORY OF FLIGHT
On August 2, 1998, approximately 2145 Pacific daylight time (PDT), a Cessna 177, N2213Y, was observed to depart Wells, Nevada. The commercial pilot-in-command of the aircraft, who was its sole occupant, did not file a flight plan for this flight, and no air traffic services were provided to the flight after it departed Wells. The pilot's family reported the aircraft as missing to the FAA on August 9, 1998, and an Alert Notice (ALNOT) was issued for the aircraft on August 9 at 1726 Coordinated Universal Time (UTC). On August 12, 1998, a Montana Department of Aeronautics search aircraft sighted aircraft wreckage on the west slope of 12,204-foot Mount Rearguard, approximately 10 miles southwest of Red Lodge, Montana. On August 13, 1998, a ground search-and-rescue party reached the aircraft wreckage and confirmed that it was the wreckage of N2213Y. The aircraft was destroyed, and the pilot was found dead at the scene. The destination of the 14 CFR 91 flight was not determined, although both Wells and the accident site were approximately on a direct line of flight from the aircraft's home base of Santa Rosa, California, to Minot, North Dakota (which was listed as a potential intermediate destination in the ALNOT.)
The ALNOT indicated that the pilot originally departed Santa Rosa at 1800 PDT on August 2 and intended to fly to the Experimental Aircraft Association (EAA) AirVenture '98 Fly-In at Oshkosh, Wisconsin. Information obtained from the FAA Automated Flight Service Station (AFSS) at Grand Forks, North Dakota, indicated that the pilot contacted the Rancho Murieta, California, AFSS via radio over the Marysville, California, VOR/DME facility at 1823 PDT on August 2, and requested the winds aloft at Reno, Nevada, and Salt Lake City, Utah.
On August 3, from 0158:38 to 0202:58 mountain daylight time (MDT) (approximately 3 1/4 hours after N2213Y's departure from Wells), the Salt Lake Air Route Traffic Control Center (ARTCC) recorded a 1200 beacon code tracking into the accident area, on a generally straight northeasterly track at an altitude between 11,600 and 11,800 feet. The last radar return of this series, at 0202:58 MDT, was approximately 1 1/2 nautical miles southwest of the crash site at an altitude of 11,600 feet. The accident site was approximately at the 11,900 foot level.
The accident occurred at 45 degrees 3.0 minutes North and 109 degrees 31.8 minutes West.
PERSONNEL INFORMATION
The accident pilot was a former U.S. Air Force navigator and electronic warfare officer. He held a commercial pilot certificate with airplane single engine land, airplane multiengine land, instrument airplane, and glider ratings. The date of issue of the pilot's commercial pilot certificate was July 16, 1978. On his most recent application for an FAA medical certificate, on January 16, 1997, the pilot gave his total civil flight time as 3,800 hours. Pilot logbooks for the accident pilot were not recovered by the NTSB. The pilot gave his occupation to the Department of Veterans' Affairs in San Francisco, California, as "aircraft mechanic", although FAA records do not indicate that he held an FAA mechanic certificate.
The accident pilot's January 16, 1997, medical certificate application was denied by the FAA, and the pilot did not possess an FAA medical certificate at the time of the accident. Pertinent details of the pilot's medical history and the FAA's denial of the pilot's medical certificate application are presented in the MEDICAL AND PATHOLOGICAL INFORMATION section below.
AIRCRAFT INFORMATION
According to aircraft records provided to the NTSB, the accident aircraft (a Cessna 177, serial number 17700013) had been modified by installation of a Textron Lycoming O-360-A1F6D engine (serial number L-17962-36A) and McCauley B2D34C211 two-blade, constant-speed propeller (replacing the originally installed McCauley two-blade, fixed-pitch propeller) per FAA field approval on June 18, 1988. The modified engine installation provided an increase from the originally installed Lycoming O-320-E2D engine's 150 horsepower (HP) to 180 HP. The airplane's last annual inspection was on August 1, 1997, approximately 64 tachometer hours prior to the accident. The aircraft records and engine tachometer reading at the accident site indicated that at the time of the accident, the airframe total time was 3,522.6 hours, and the engine total time was 2,870.2 hours. The engine log indicated that the engine was "top overhauled" on April 14, 1988, two months prior to installation on the accident aircraft, and that all four cylinders had been "top overhauled" in conjunction with the annual inspection, in July 1997. However, there was no record that the engine had ever undergone a major overhaul since original manufacture in June 1973. Textron Lycoming service instructions give the recommended time between overhauls for O-360-A1F6D engines as a maximum of 2,000 hours (or in the 12th year of service, for engines that do not accumulate the hourly intervals of time between overhauls in that period of time.)
The owner's manual for the 1975 Cessna 177B (a variant of the type certified with a 180-HP O-360-A1F6D engine and constant speed propeller, with approximately equal wing area and a maximum gross weight of 2,500 pounds as compared to the accident aircraft's 2,350 pounds) gives the model 177B's service ceiling as 14,600 feet.
According to the aircraft records, the airplane was autopilot-equipped. Also, according to the aircraft records, components had been installed in conjunction with the last annual inspection to enable the aircraft to supply electrical power to a Garmin GPS 90 portable Global Positioning System (GPS) receiver.
METEOROLOGICAL INFORMATION
The nearest weather reporting station to the accident site is the AWOS-3 automated weather observation system at Cody, Wyoming. Cody is at an elevation of 5,098 feet and is approximately 38 nautical miles southeast of the accident site. At 0155 MDT on August 3, Cody reported scattered clouds at 8,000 feet, visibility 10 statute miles, and calm winds. In its 0215 automated METAR observation, reported cloud cover and visibility were unchanged and winds were reported from 260 degrees at 3 knots. At 0235, conditions were reported as 4,900 feet scattered, 7,000 feet broken, 10 statute miles visibility, and calm winds.
The 0156 automated METAR observation on August 3 at Billings, Montana (62 nautical miles northeast of the accident site, elevation 3,674 feet), reported scattered clouds at 6,500 feet, overcast clouds at 11,000 feet, 10 statute miles visibility, and winds from 320 degrees at 14 knots. At 0256, Billings reported scattered clouds at 5,000 feet, overcast at 8,500 feet, 10 statute miles visibility, and winds from 310 degrees at 13 knots.
The 0156 automated METAR observation on August 3 at Bozeman, Montana (81 nautical miles northwest of the accident site, elevation 4,474 feet) reported few clouds at 2,700 feet, broken clouds at 5,000 feet, overcast clouds at 11,000 feet, and calm winds. At 0256, Bozeman reported broken clouds at 3,900 feet, broken clouds at 5,000 feet, overcast at 6,000 feet, 10 statute miles visibility, and calm winds.
Astronomical data computation indicated that on the evening of August 2-3, moonset in the accident area was at 0205, with 77% moon illumination prior to moonset.
AIDS TO NAVIGATION
Following the accident, investigators examined terrain depiction in the accident area on the Great Falls Sectional Aeronautical Chart. This examination revealed that the Great Falls Sectional Aeronautical chart depicts an 11,360-foot critical elevation (844 feet below the elevation of Mount Rearguard) approximately 1 1/2 nautical miles east-northeast of Mount Rearguard. This 11,360-foot elevation, adjacent to the 109 degree 30 minute West meridian, is the highest elevation in the 30-minute latitude/longitude quadrangle adjacent to, and east of, the 30-minute latitude/longitude quadrangle in which the accident site lies, and as such is the defining elevation for computation of the Maximum Elevation Figure (MEF) for the adjacent quadrangle in accordance with Interagency Air Cartographic Committee (IACC) standards. The 11,360-foot critical elevation is not a peak, but is in fact a point on a sloping east-west oriented plateau which rises to a peak elevation of 11,879 feet about 1 mile to the west. Mount Rearguard is depicted on the sectional chart with an unlabeled contour circle of approximately 3/32 inch diameter, but is not presented as a critical elevation.
Examination of the U.S. Forest Service 1:63,360-scale topographic map of the Absaroka-Beartooth Wilderness of Montana and Wyoming revealed six peaks within 5 statute miles of the 11,360-foot critical elevation (including Mount Rearguard) whose elevations exceed 11,360 feet, and which are not themselves presented as critical elevations on the sectional chart. The highest of these, Whitetail Peak (approximately 4 3/4 statute miles west-northwest of the 11,360-foot critical elevation and 4 statute miles northwest of the accident site), rises to an elevation of 12,548 feet.
The Office of Aeronautical Charting & Cartography (AC&C), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA), furnished the guidance used for depiction of elevations on aeronautical charts to the NTSB. The publication containing this guidance is known as IACC-2. IACC-2 guidance regarding presentation of elevations states the following:
An adequate pattern of spot elevations should be distributed throughout the various elevation levels, specifically including the highest points in each area and significant lower points. Elevations which are not considered significant shall normally be omitted. Determinations as to what constitutes a significant elevation or a significant lower point are matters of cartographic judgment and discretion....Spot elevations ...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# SEA98FA161