# NTSB DEN04LA051: Shook Rans S-12, N7138K, Berthoud, CO, March 8, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 7, 2004, 17:15 local (Mar 8, 2004, 00:15 UTC) - Place: Berthoud, CO - Coordinates: 40.308334, -105.083335 - Nearby events: https://openairdocs.org/map.md?lat=40.3083&lon=-105.0833&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report September 29, 2004 - Report: Approved by Office Director - Parties: FAA FSDO - NTSB case key (mKey): 58872 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN04LA051 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/58872/pdf - Page: https://openairdocs.org/ntsb/DEN04LA051 ## Probable cause the pilot's improper flare and his inadequate compensation for wind. The wind gust was a contributing factor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Hard landing, landing - flare/touchdown - compensation for wind conditions - inadequate, pilot in command (cause) - weather condition - gusts (contributing factor) - flare - improper, pilot in command (cause) - Gear collapsed, landing - flare/touchdown - aircraft control - not maintained, pilot in command (cause) - stall/mush - inadvertent, pilot in command (contributing factor) ## Analysis According to the pilot, he had entered a left downwind traffic pattern for the east/west runway, intending to land to the east. He "checked the wind sock and it was just fluttering with a very slight, if at all, crosswind... from the north." During the landing flare, he encountered a gust of wind from the north and the airplane stalled approximately 10 feet above the ground. The airplane bounced once and during the second impact with the ground, all three landing gear collapsed, substantially damaging the airplane. According to the FNL METAR (aviation routine weather report) taken at 1715, winds were reported as 150 degrees at 3 knots. ## Factual narrative On March 7, 2004, at approximately 1715 mountain standard time, a Shook Rans S-12, N7138K, was substantially damaged when the landing gear collapsed following collision with terrain at the Lazy W, a private airstrip near Berthoud, Colorado. The private pilot, the sole occupant on board, was not injured. Visual meteorological conditions prevailed. No flight plan had been filed for the local flight being conducted under the provisions of Title 14 CFR Part 91. The flight departed at approximately 1610. According to the pilot, he was practicing landings at both the Lazy W airstrip and the Ft. Collins-Loveland Airport (FNL). (Lazy W is approximately 5 nautical miles southwest of FNL.) The pilot reported that he entered a left downwind traffic pattern for the east/west runway at Lazy W, intending to land to the east. He "checked the wind sock and it was just fluttering with a very slight, if at all, crosswind... from the north." During the landing flare, he encountered a gust of wind from the north and the airplane stalled approximately 10 feet above the ground. The airplane bounced once and during the second impact with the ground, all three landing gear collapsed, wrinkling the fuselage. According to the FNL METAR (aviation routine weather report) taken at 1715, winds were reported as 150 degrees at 3 knots. ## Aircraft - Registration: [N7138K](https://openairdocs.org/aircraft/N7138K), registered now, S/N 1094523, built 1995 (OpenAirDocs) - Reported make and model: Shook Rans S-12 - Registry model: [Shook Mark S RANS S-12](https://openairdocs.org/model/shook-mark-s-rans-s-12) (registry code 05626VH) (OpenAirDocs) - Registry engine: [Bombardier ROTAX (ALL)](https://openairdocs.org/engine/bombardier-rotax-all) (registry code 09050, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1094523 - Airframe hours: 181.9 - Engines: Rotax 618 75 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, September 12, 2003, 34.6 hours before - Departed: Berthoud, CO - Destination: Berthoud, CO - Airport: PVT, Lazy W (Private strip), runway 090, 2,600 × 60 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: none; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; last flight review October 9, 2003; seat: left; flight hours: 130 total, 32 in this make and model, 130 as pilot in command, 17 in the last 90 days, 6 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 59 °F, dew point 23 °F - Altimeter: 30.37 inHg - Observed at: FNL, 10 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 20040307003239A](https://openairdocs.org/incident/20040307003239A), Mar 7, 2004: Amtr RANSS12, Berthod, CO, Substantial damage. (-23) Aircraft was over the runway about to land when a gust of wind upset the aircraft, pilot added power but the aircraft stalled about 10 above the runway… ## Other investigations on N7138K (1) 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 CEN12LA102](https://openairdocs.org/ntsb/CEN12LA102), Dec 8, 2011: Shook Rans S-12 (N7138K), Festus, MO, substantial damage. Probable cause: The certified flight instructor’s delayed remedial action as the airplane neared an aerodynamic stall/spin. Contributing to the accident was that the student pilot did not maintain adequate airspeed… 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.