# NTSB SEA97FA067: Beech 200, N117WM, Salt Lake City, UT, March 3, 1997 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: March 2, 1997, 19:13 local (Mar 3, 1997, 02:13 UTC) - Place: Salt Lake City, UT - Coordinates: 40.810245, -111.939155 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.8102&lon=-111.9392&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal, 3 serious - Status: Completed, report February 28, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 42494 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA97FA067 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42494/pdf - Page: https://openairdocs.org/ntsb/SEA97FA067 ## Probable cause The pilot's failure to maintain adequate airspeed on the ILS approach, resulting in a stall. Factors included: low visibility; the pilot's selection of the improper DME for the approach; his resulting failure to attain the proper descent profile for the approach; and insufficient altitude available for stall recovery. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, approach - faf/outer marker to threshold (ifr) - weather condition - obscuration (contributing factor) - approach receiver - improper, pilot in command (contributing factor) - planned approach - not attained, pilot in command (contributing factor) - airspeed(vso) - not maintained, pilot in command (cause) - stall, pilot in command - remedial action - not possible - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis The flight was on a coupled instrument landing system (ILS) approach with 1/2 mile visibility in snow showers. Three successive fixes on the localizer are defined by distance measuring equipment (DME) paired with the ILS; prior to the ILS DME commissioning 6 months before the accident, the DME fixes were defined by a VORTAC 4.7 nautical miles past the ILS DME. The aircraft was 800 feet high at the first fix and 1,500 feet high at the second, but approximately on altitude 4.7 nautical miles past the first and second fixes, respectively. It passed the outer marker 900 feet high and captured the glide slope from above about 1.8 nautical miles from the threshold, 500 feet above decision height (DH) and 700 feet above touchdown. The aircraft was on glide slope for 28 seconds, during which time its speed decayed to stall speed; it then dropped below glide slope and crashed 1.3 nautical miles short of the threshold. The pilot's FLT DIR DME-1/ DME-2 switch, which control the DME display on the pilot's horizontal situation indicator (HSI), was found set to DME-2; the NAV-2 radio was set to the VORTAC frequency. Up to 800 feet may be required for stall recovery. ## Factual narrative HISTORY OF FLIGHT On March 2, 1997, approximately 1913 mountain standard time, a Beech 200 Super King Air, N117WM, registered to Coast Hotels and Casinos Inc. of Las Vegas, Nevada, collided with terrain approximately 1.3 nautical miles short of the runway while on an instrument landing system (ILS) approach to runway 34R at Salt Lake City International Airport, Salt Lake City, Utah. The airplane was substantially damaged and, of the airplane's four occupants, one passenger was fatally injured and the airline transport pilot-in-command and the aircraft's other two passengers were seriously injured. The 14 CFR 91 executive/corporate flight originated at McCarran International Airport, Las Vegas, Nevada. Night instrumental meteorological conditions existed at the time, and the flight was on an instrument flight rules (IFR) flight plan. The pilot reported that the flight proceeded uneventfully to the Fairfield VOR, and initial approach fix (IAF) for the ILS runway 34R approach. The pilot stated that he was then given a vector by air traffic control (ATC) to intercept the runway 34R localizer. A transcript of the communications between N117WM and Salt Lake Approach indicated that at 1859:56, after the pilot of N117WM checked in at an altitude of 15,000 feet, Salt Lake Approach instructed N117WM: "...roger two six miles from plage turn right heading zero one zero cross plage at or above one one thousand cleared ILS runway three four right approach." (NOTE: PLAGE, SCOER, and KERNN intersections are successive fixes on the ILS approach. All are located on the runway 34R localizer course, with KERNN being collocated with the outer marker.) The Salt Lake approach controller then advised "lear seven whiskey mike" that the runway visual range (RVR) for runway 34R was out of service, and that the visibility was 1/2 mile. According to the ATC transcript N117WM replied "(unintelligible) seven whiskey mike" to this. ATC recorded radar data indicated the N117WM began its descent from 15,000 feet at 1901:45, 18 nautical miles south of PLAGE. The pilot indicated in his report of the accident that the aircraft's autopilot was coupled in the approach mode for the approach. At 1901:48, Salt Lake Approach asked N117WM to "say air speed", and the pilot of N117WM replied that he was "indicating one eight zero." Salt Lake Approach then instructed N117WM to "maintain best forward speed." According to the ATC radar data, N117WM subsequently started a left turn to the localizer, at about 1903:45. At 1904:49, Salt Lake Approach instructed N117WM to "...maintain best forward speed until ah score [sic] cross kernn at one seven zero knots contact tower now one one niner point five." The transcript indicated that the best possible interpretation of the pilot's reply was, "(score [sic] forward speed) best forward speed till score [sic]. At 1905:25, N117WM checked in with Salt Lake Tower, reporting out of 12,500 feet for 11,000 feet. Salt Lake Tower instructed "king air one one seven whiskey mike" to continue, at 1905:25, then corrected the call sign at 1906:16, instructing "king air one seven whiskey mike" to continue. The pilot of N117WM replied "say again" to this, at 1906:23 and again at 1906:28, and the controller repeated the instruction to continue at 1906:40. The ATC radar data indicated the N117WM passed abeam PLAGE about 1906:32, at an altitude of 11,800 feet (800 feet above the minimum altitude specified in the ATC clearance and 1,300 feet above the published minimum altitude at PLAGE) and abeam SCOER about 1907:55, at an altitude of 10,500 feet (1,500 feet above the minimum altitude at SCOER depicted on the published approach procedure.) At 1910:17, Salt Lake Tower called: king air one one seven whiskey mike caution wake turbulence boeing seven fifty seven six miles ahead wind three six zero at one five runway three four right cleared to land." (N117WM was following DAL616, a Boeing 757 [B-757] aircraft, on the ILS approach. ATC radar data showed that at the time DAL616 arrived over the runway threshold, N117WM was approximately 5.4 nautical miles behind the B-757. ATC minimum radar separation distance for landing, for a small aircraft following a B-757, is 5 miles.) The approach procedure specifies that a descent to a glide slope intercept altitude of 7,100 feet (minimum) is initiated at SCOER. Based on the published glide slope angle of 3.00 degrees, threshold crossing height (TCH) of 53 feet, and touchdown zone elevation (TDZE) of 4,222 feet, glide slope intercept at 7,100 feet altitude was computed by investigators to occur approximately 8.9 nautical miles from the runway threshold, or about 6.5 nautical miles past SCOER. ATC radar data indicated that N117WM crossed KERNN, the outer marker, at 1910:51, at 7,00 feet and a radar-indicated speed of 163 knots. The glide slope altitude at KERNN, as depicted on the approach procedure profile view, is 6,095 feet. At 1911:14, Salt Lake Tower informed N117WM of an Embraer EMB-120 aircraft holding in position on the runway; the acknowledgment of this call by N117WM, at 1911:20, was the last reported radio transmission from the accident aircraft. ATC radar data indicated that the aircraft remained above the glide slope from KERNN until attaining the glide slope from above about 1.8 nautical miles from the threshold, at 1912:42, 4,900 feet altitude (478 feet above decision height) and a radar ground speed of 103 knots. The aircraft remained generally on the glide slope for 28 seconds, from 1912:42 until 1913:10, at which point its radar ground speed indicated 73 knots. During the 28-second period the aircraft was on the glide slope, its average rate of radar groundspeed decay increased from 0.54 knots per second (between KERNN and the time of glide slope capture) to 1.07 knots per second. At 1913:14, the aircraft dropped well below the glide slope and its radar speed reached its minimum value of 70 knots. The loss of 200 feet of altitude (from 4,700 to 4,500 feet) from 1913:10 to 1913:14, in combination with the radar ground speed of 70 knots during this interval, was computed to correspond to an average downward vertical flight path angle during the interval of 20.3 degrees below the horizontal. The last radar return recorded was at 1913:18, at 4,400 feet altitude (approximately 200 feet above the touchdown zone elevation) and 71 knots. The crash site was approximately 1.3 nautical miles short of the runway 34R threshold, about 1/4 mile left of the localizer centerline. The pilot's recollection of the accident sequence, as given in the narrative in his report of the accident, was as follows: ...Being slightly above the glide slope, the auto-pilot did not capture the altitude. The rate of descent was increased and the auto-pilot captured the glide slope. At this time, the aircraft was entering the cloud deck, all anti-icing and de-icing systems were verified on, approach flaps were lowered and the gear was extended. Power was adjusted to approximately 600 ft. lbs. [torque] per engine in order to maintain 140 [k]nots IAS. From this point until the last few seconds of the flight I have no memory recall. My next recollection is descending through 400 ft. AGL on the radar altimeter. The aircraft did a sudden, uncommanded, skidding yaw to the left, with a following nose down, wing down roll to the left. My instinctive reaction was full right aileron, full right rudder, full power and nose up pitch. At this time I had visual outside the aircraft. The control input slowed the rate of roll and the aircraft started to return to level flight. As I began to relax the controls [inputs], the rolling motion returned. At this time I could see a large, white space in front of me, and I could visually see that the aircraft was descending. I had full control input in, attempting to level the aircraft prior to impact. I do not recall the impact. The two survivin ## Aircraft - Registration: N117WM (not matched to a registry record) - Reported make and model: Beech 200 - Category: Airplane - Serial number: BB-662 - Airframe hours: 4692 - Engines: P&W PT6A-41 850 horsepower turbo prop - Damage: Substantial damage - Flight: Executive/Corporate, Part 91 - Registered owner: Coast Hotels & Casinos Inc. - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, May 23, 1996, 174 hours before - Departed: LAS, LAS VEGAS, NV - Destination: SLC - Flight plan: IFR - Airport: SLC, Salt Lake City Intl, runway 34R ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 8,172 total, 1,841 in this make and model, 8,150 as pilot in command, 61 in the last 90 days, 25 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Dusk - Wind: 340° at 18 knots - Visibility: 0.5 statute miles - Lowest ceiling: 1,100 ft - Temperature: 93 °F, dew point 90 °F - Altimeter: 29.00 inHg - Observed at: SLC, 2 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 19970303001949A](https://openairdocs.org/incident/19970303001949A), Mar 3, 1997: Beech 200BEECH, Salt Lake City, UT, Substantial damage, 1 fatal. Crashed short of approach end of runway while on final approach. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; 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.