# NTSB DEN01LA163: Grumman-Schweizer G-164A, N9925, Parowan, UT, September 27, 2001 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 27, 2001, 09:00 local (15:00 UTC) - Place: Parowan, UT - Coordinates: 37.884723, -112.65139 - Nearby events: https://openairdocs.org/map.md?lat=37.8847&lon=-112.6514&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 6, 2002 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 53516 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN01LA163 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/53516/pdf - Page: https://openairdocs.org/ntsb/DEN01LA163 ## Probable cause the pilot's failure to maintain adequate airspeed which resulted in an inadvertent stall/mush into terrain. Contributing factors were the pilot's diverted attention, the rising terrain, and the high density altitude weather condition. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, maneuvering - aerial application - airspeed - not maintained, pilot in command (cause) - diverted attention, pilot in command (contributing factor) - stall/mush - inadvertent, pilot in command (cause) - terrain condition - rising (contributing factor) - weather condition - high density altitude (contributing factor) ## Analysis The pilot said that he completed an application pass, and turned his head to look for his flagman. He said there was rising terrain in front of him, and he immediately applied full power. The airplane began losing airspeed, and he was unable to increase the climb rate. The airplane impacted the ground in a rough ravine. The left wing spar was bent up and the fuselage was wrinkled. The calculated density altitude was 9,736 feet. ## Factual narrative On September 27, 2001, at approximately 0900 mountain daylight time, a Grumman-Schweizer G-164A, N9925, was substantially damaged when it impacted terrain while maneuvering during an aerial application pass near Parowan, Utah. The commercial pilot, the sole occupant in the airplane, was not injured. The airplane was being operated by Parowan Crop Dusting Services, Inc., Parowan, Utah, under Title 14 CFR Part 137. Visual meteorological conditions prevailed for the local aerial application flight that originated approximately 30 minutes before the accident. The pilot said that he completed an application pass, and turned his head to look for his flagman. He said there was rising terrain in front of him, and he immediately applied full power. The airplane began losing airspeed, and he was unable to increase the climb rate. The airplane impacted the ground in a rough ravine. The left wing spar was bent up and the fuselage was wrinkled. The calculated density altitude was 9,736 feet. ## Aircraft - Registration: [N9925](https://openairdocs.org/deregistered/N9925-2011-06-14), registration cancelled 2011-06-14, S/N 1331, built 1974 (OpenAirDocs) - Reported make and model: Grumman-Schweizer G-164A - Registry model: [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a) (registry code 3952801) (OpenAirDocs) - Registry engine: [Continental R-975 series](https://openairdocs.org/engine/continental-r-975-series) (registry code 17037, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1331 - Airframe hours: 7426 - Engines: Continental R-975-46A GA2 525 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Parowan Crop Dusting Services, Inc. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, June 1, 2001, 49 hours before - Departed: 1L9, Parowan, UT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2; last flight review November 15, 2000; seat: front; flight hours: 1,692 total, 250 in this make and model, 1,530 as pilot in command, 160 in the last 90 days, 21 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 0 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 59 °F, dew point 43 °F - Altimeter: 30.19 inHg - Observed at: CDC, 15 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 20010927027399A](https://openairdocs.org/incident/20010927027399A), Sep 27, 2001: Scwzer G164A, Parowan, UT, Destroyed. (.19) On September 27, 2001, at approximately 0900 mountain daylight time, a grumman-schweizer G-164A, N9925, was substantially damaged while maneuvering… ## Other investigations on N9925 (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 LAX84LA474](https://openairdocs.org/ntsb/LAX84LA474), Sep 8, 1984: Grumman 164A (N9925), Goodyear, AZ, substantial damage - [NTSB OAK76DVG70](https://openairdocs.org/ntsb/OAK76DVG70), May 8, 1976: Grumman G-164A (N9925), Butte City, CA, 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.