# NTSB SEA01LA133: Piper PA-28R, N8475C, Cut Bank, MT, July 10, 2001 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: July 10, 2001, 10:00 local (16:00 UTC) - Place: Cut Bank, MT - Coordinates: 48.650085, -112.840881 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=48.6501&lon=-112.8409&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report September 19, 2001 - Report: Approved by Office Director - Parties: Helena FSDO - NTSB case key (mKey): 52713 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA01LA133 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/52713/pdf - Page: https://openairdocs.org/ntsb/SEA01LA133 ## Probable cause The pilot's failure to maintain a speed above stall velocity (Vs) during the after-takeoff climb. Factors include a high density altitude, and a dust devil/whirlwind located along the route of departure. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, climb - airspeed(vs) - not maintained, pilot in command (cause) - stall/mush - inadvertent, pilot in command - weather condition - dust devil/whirlwind (contributing factor) - weather condition - high density altitude (contributing factor) ## Analysis During the after-takeoff climb in high density altitude conditions, the aircraft encountered a dust devil/whirlwind that altered its attitude and heading. Although the pilot was able to recover from this upset, the aircraft was then headed for the knoll of a small hill. The pilot therefore raised the nose of the aircraft in an attempt to clear the knoll, but in doing so he allowed the airspeed to deteriorate, and the aircraft subsequently stall/mushed into the terrain. ## Factual narrative On July 10, 2001, approximately 1000 mountain daylight time, a Piper PA-28R, N8475C, impacted the terrain after taking off from Linberg Ranch, a private airstrip located about 17 miles north of Cut Bank, Montana. The private pilot and his passenger received minor injuries, but the aircraft, which is owned and operated by the pilot, sustained substantial damage. The intended destination of the 14 CFR Part 91 personal pleasure flight, which was being operated in visual meteorological conditions, was Glasgow, Montana. No flight plan had been filed. The ELT, which was activated by the impact, was turned off at the scene. According to the pilot, because the takeoff took place on a rough grass airstrip, the aircraft accelerated slowly and lifted off near the departure end of the 2,600 foot runway. After becoming airborne, while flying just above stall speed, the aircraft flew through a dust devil/whirlwind. As it flew through the whirlwind, the aircraft rolled to the right and pitched nose-up. Although the pilot was able to recover from the whirlwind-induced upset, the aircraft was then heading for the knoll of a small hill. The pilot therefore raised the nose of the aircraft in an attempt to climb over the knoll, but the airspeed began to drop, and the aircraft subsequently stalled/mushed into the terrain. At the time of the accident, the temperature was approximately 75 degrees Fahrenheit. The field elevation was 3,800 feet above mean sea level (MSL), and the altimeter setting at Cut Bank was 30.05 inches of Mercury. Based on these ambient conditions, the density altitude was calculated to be approximately 5,640 feet. It was also determined that the aircraft's weight was about 230 pounds below maximum allowable gross weight. The pilot reported that there did not appear to be any malfunction of the engine or other aircraft system. A post-accident inspection of the engine did not disclose any evidence of a malfunction. ## Aircraft - Registration: [N8475C](https://openairdocs.org/deregistered/N8475C-2002-01-14), registration cancelled 2002-01-14, S/N 28R-7635162, built 1976 (OpenAirDocs) - Reported make and model: Piper PA-28R - Registry model: [Piper PA-28R-200](https://openairdocs.org/model/piper-pa-28r-200) (registry code 7102811) (OpenAirDocs) - Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 28R-7635162 - Airframe hours: 4964 - Engines: Lycoming IO-360-C1C 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Ramon N. Archer - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 3, 2001, 0 hours before - Departed: Linberg Ranch, MT - Destination: GGW, Glascow, MT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 69; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; last flight review April 11, 2001; seat: left; flight hours: 1,098 total, 923 in this make and model, 28 in the last 90 days, 17 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 235° at 5 knots - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 75 °F - Altimeter: 30.04 inHg ## 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 20010710019129A](https://openairdocs.org/incident/20010710019129A), Jul 10, 2001: Piper PA28R200, Cut Bank, MT, No damage. (-23) The pilot stated that after take-off, he raised the nose to clear a small knoll and the aircraft mushed and hit the knoll. 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.