# NTSB SEA95LA217: Schweizer SGS 1-26B, N2478W, Morgan, UT, September 14, 1995 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: September 14, 1995, 16:10 local (22:10 UTC) - Place: Morgan, UT - Coordinates: 41.010925, -111.66925 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.0109&lon=-111.6693&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report May 9, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 42248 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA95LA217 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42248/pdf - Page: https://openairdocs.org/ntsb/SEA95LA217 ## Probable cause Failure of the pilot to maintain adequate airspeed, while maneuvering to land after a low altitude tow release, which resulted in a stall/spin and collision with terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Miscellaneous/other, takeoff - initial climb - glider/tow release - Loss of control - in flight, maneuvering - airspeed - not maintained, pilot in command (cause) - stall/spin - inadvertent, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled ## Analysis The tow plane pilot reported that the glider released at an estimated altitude of 100-150 feet AGL, approximately midfield, during the takeoff/initial climb. Several witnesses observed the glider yawing/swerving back and forth and then release. The glider pilot executed a left turn back toward the runway. Witnesses reported that during the turn, the glider entered a stall/spin and impacted the ground. No mechanical malfunctions with either the glider's controls or the tow release hook mechanism were found. The tow rope was found to be intact following the accident. ## Factual narrative HISTORY OF FLIGHT On September 14, 1995, approximately 1610, mountain daylight time, a Schweizer SGS 1-26B glider, N2478W, registered to and being flown by a 74 year old private pilot, was destroyed during collision with terrain during an uncontrolled descent following a loss of control in flight while maneuvering. The glider had just departed the Morgan County Airport, Morgan, Utah. The pilot, who initially survived the impact, expired several hours later. Visual meteorological conditions prevailed and no flight plan had been filed. The flight, which was personal, was to have been operated under 14CFR91. The pilot of the tow aircraft reported taking off on runway 21 (3,800 feet in length) at 1605. He reported the winds at 240 degrees and 10 to 12 miles per hour. Shortly after takeoff (approximately 800 feet down the runway) he noticed a slight jerk on the tow rope and looked in the rear-view mirror at the glider noting that it was "back in position, possibly slightly low, but no slack in the rope." Thereafter, the tow pilot noted a dramatic increase in rate of climb and looked back at the glider observing it "in an approximate 30 degree bank to the left." The pilot returned to the Morgan County airport during which he observed the accident site. Subsequent to landing, the towplane pilot ascertained that the glider's tow hook was open (in the release position) and examined the tow rope finding it intact and in normal condition. Additionally, he estimated that the glider pilot "cut loose from the towplane before reaching the mid-point of the runway and at an altitude less than 150 feet and greater than 100 feet" (refer to attached statement). One witness who reported observing the glider during the accident sequence stated that he "saw the glider on tow. It began to yaw left to right, while way off to the right (from the glider's perspective). The glider released off tow. At first the glider went straight (about 100 yards) then it started a very slow bank to the left. At that point the glider stalled and "spun in" to the ground (turning to the left continuously)." A second witness reported that "After the glider was airborne a little, he began to swerve back & forth quite a bit veering to the west side of the runway. About that time, the tow rope came off & the glider straightened up then turned back towards the north end of the runway. While in the turn the glider appeared to stall & spin about two complete turns & struck the ground facing north." (Both witnesses submitted statements included in Morgan County Sheriff's Department Report Case Number 95-0961). AIRCRAFT INFORMATION Paperwork retrieved from the aircraft indicated that the pilot had purchased and registered the glider on August 26, 1995. Additionally, the glider's logbook showed that on August 23, 1995, FAA Airworthiness Directive (AD) 87-02-1 was complied with. This AD established maintenance and inspection procedures to insure that the tow hook does not inadvertently slip out of the release arm. PERSONNEL INFORMATION According to FAA records the pilot obtained a student pilot certificate (glider only) on September 2, 1971, and received a private pilot certificate with a glider rating on October 9, 1971. The records showed that the pilot requested a duplicate certificate on May 4, 1993. No other airman certification information was noted regarding ratings or dates. No airman medical information existed within the FAA records and a glider rated private pilot is not required to maintain an airman's medical certificate. A pilot's glider logbook labelled "#2" was provided by the FAA and showed an opening date of April 30, 1994, with 55.6 hours of dual and 20.7 hours of solo (pilot-in-command) flight time brought forward. Between April 30, 1994, and August 30, 1995, the logbook showed an additional 18.8 hours of dual and 25.8 hours of solo flight time. Total flight time logged was approximately 121 hours, of which 37% was logged during the 16 month period shown in this logbook spanning a total of 67 flights. The logbook showed only two flights in the SGS 1-26B glider (N2478W), the first on August 28th and the second on 30th of 1995. Additionally, the last open page of the logbook contained a handwritten entry as follows: "26 Aug 95 - I certify that on this date I gave Mr. Cornell Ridderhoff a cockpit check in, and discussed handling & performance characteristics of the SGS-1-26. Stanley E. McGrew CFIG 1240495 EXP 04/97" WRECKAGE AND IMPACT INFORMATION On site examination was conducted by inspectors from the FAA's Salt Lake City Flight Standards District Office (FSDO). The aircraft crashed at a location several hundred feet east of runway 03/21 and approximately midfield (refer to CHART I). The inspectors reported finding no evidence of any control surface malfunction or mis-rigging. Additionally, they reported finding no evidence of a malfunction or premature release of the tow rope release mechanism (refer to Attachment F-I). The outboard leading edge of the left wing was observed to display crushing damage and was bent upwards slightly and the right wing rear attach point was observed to be broken (refer to photographs 1/2 and DIAGRAM I). MEDICAL AND PATHOLOGICAL INFORMATION Post mortem examination of the pilot was conducted by Maureen J. Frikke, M.D., at the Offices of the Medical Examiner, 48 North Medical Drive, Salt Lake City, Utah, 84113, on September 15, 1995. The pilot received medical treatment during the short time period following the accident and prior to his expiration. Toxicological evaluation of samples from the pilot was conducted by both the State of Utah and the FAA's Toxicology and Accident Research Laboratory. All tests were negative (refer to attached reports). ADDITIONAL INFORMATION The following items were sent to the NTSB by FAA personnel from the Salt Lake FSDO: Sailplane Log Book + one yellow tag Pilot Logbook #2 FAA Form 1362 (Airworthiness Certificate) Form 8050-1 (pink copy - acft registration application) Two pieces of the tow release hook from N2478W Schweizer Sailplane Flight manual These items were sent via certified mail to the pilot's address on March 8, 1995. ## Aircraft - Registration: [N2478W](https://openairdocs.org/deregistered/N2478W-1997-10-02), registration cancelled 1997-10-02, S/N 375 (OpenAirDocs) - Reported make and model: Schweizer SGS 1-26B - Registry model: [Schweizer SGS 1-26B](https://openairdocs.org/model/schweizer-sgs-1-26b) (registry code 8050118) (OpenAirDocs) - Category: Glider - Serial number: 375 - Airframe hours: 1756 - Engines: unknown - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Ridderhoff, Cornell, C. - Airworthiness certificate: Standard, Aerobatic - Last inspection: Annual, August 23, 1995, 1 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 74; private; medical: unknown; seat: center; toxicology performed; flight hours: 121 total, 1 in this make and model, 46 as pilot in command, 11 in the last 90 days, 2 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 4 knots - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 37 °F - Altimeter: 30.00 inHg - Observed at: HIF, 9 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 19950914029579A](https://openairdocs.org/incident/19950914029579A), Sep 14, 1995: Scwzer SGS126B, Morgan, UT, Destroyed, 1 fatal. Glider pilot cut loose from tow plane low on climbout. Banked stalled and spun in. New purchase unskilled in type. ## Other investigations on N2478W (2) 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. - [NTSB LAX83LA209](https://openairdocs.org/ntsb/LAX83LA209), May 1, 1983: Schweizer SGS 1-26B (N2478W), Chula Vista, CA, substantial damage - [NTSB LAX70DUJ25](https://openairdocs.org/ntsb/LAX70DUJ25), Mar 28, 1970: Schweizer 1-26B (N2478W), Chandler, AZ, substantial damage 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.