# NTSB SEA00LA065: Aero Design Eleven 12, N80XP, Spokane, WA, April 10, 2000 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 10, 2000, 12:45 local (19:45 UTC) - Place: Spokane, WA - Coordinates: 47.649799, -117.310775 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.6498&lon=-117.3108&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 9, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 48929 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA00LA065 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/48929/pdf - Page: https://openairdocs.org/ntsb/SEA00LA065 ## Probable cause Cracking of the weld between the tailwheel stinger housing and longitudinal cross tube, resulting in separation of the tube/tail wheel assembly from the airframe. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, landing - roll - landing gear,tailwheel assembly - cracked (cause) - landing gear,tailwheel assembly - separation - Loss of control - on ground/water, landing - roll - directional control - not possible, pilot in command ## Analysis While landing on runway 21R, and decelerating through about 25 miles per hour, the aircraft began to 'hunt.' In an effort to maintain directional control the pilot applied braking, however the aircraft ground-looped, coming to rest on the east side of the runway. When the pilot exited the aircraft he noted that the tail wheel assembly had separated from the airframe. Post-crash examination revealed that the tail wheel stinger sleeve, into which the stinger/tail wheel assembly bolts, had separated from the airframe at both the base of the rudder post and the lateral cross tube. Examination of the fracture surfaces of the sleeve where it attached to the lateral cross tube revealed discoloration of a portion of the tube end. The pilot/owner reported that only the top and bottom of the fish mouth joint had been welded to the tail wheel stinger tube where it attached to the lateral cross tube, and that 'failure at this joint allowed the tailwheel to break free of the airframe.' ## Factual narrative On April 10, 2000, approximately 1245 Pacific daylight time, an Aero Design Eleven model 12, N80XP, registered to and being flown by a commercial pilot, was substantially damaged during a loss of directional control on landing roll at Felts Field, Spokane, Washington. The pilot was uninjured. Visual meteorological conditions existed and no flight plan had been filed. The flight, which was personal, was to have been operated under 14CFR91, and originated from Spangle, Washington, approximately noon. The pilot reported that upon landing on runway 21R, and while decelerating through about 25 miles per hour the aircraft began to "hunt." In an effort to maintain directional control the pilot applied braking however, the aircraft ground looped coming to rest on the east side of the runway. When he exited the aircraft he noted that the tail wheel assembly had separated from the airframe. Post-crash examination by an inspector from the Federal Aviation Administration's Spokane Flight Standards District Office revealed that the tail wheel assembly was attached to a "stinger" (solid steel cylindrical rod). This stinger inserted into a cylindrical sleeve or hollow tube and was held in place by a single AN4 bolt and associated nut. The tube was attached at two points to the airframe; 1) the base of a vertical tube or rudder post, and 2) at the center of a laterally mounted cross tube (refer to DIAGRAM I). The sleeve in which the stinger had been bolted into was broken free from both its attach points and remained with the tail wheel assembly. Closer examination of the separation surfaces of the sleeve where it attached to the lateral cross tube revealed discoloration of a portion of the surfaces. The pilot/owner reported that upon "examining the weld on the broken end of (the) tailwheel mount (where the stinger tube is welded to the cross tube) only the top and bottom of the fish mouth joint had been welded at the point where it joins the (laterally mounted) cross tube between the lower longerons..." and the "failure at this joint allowed the tailwheel to break free of the airframe..." (refer to ATTACHMENT PS-I). The airframe total time at the time of the accident was 153.3 hours. ## Aircraft - Registration: [N80XP](https://openairdocs.org/deregistered/N80XP-2017-06-30), registration cancelled 2017-06-30, S/N 0001 (OpenAirDocs) - Reported make and model: AERO DESIGN ELEVEN 12 - Registry model: [Aero Design Eleven 12](https://openairdocs.org/model/aero-design-eleven-12) (registry code 05602F8) (OpenAirDocs) - Category: Airplane - Serial number: 0001 - Airframe hours: 153 - Engines: Vendeneyev M-14 360 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Rose, Jack A. - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, July 5, 1999 - Departed: WA62, SPANGLE, WA - Airport: SFF, Felts Field, runway 21R, 4,500 × 150 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 71; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 2,000 total, 68 in this make and model, 2,000 as pilot in command, 2 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 39 °F - Altimeter: 30.00 inHg - Observed at: SFF ## 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 20000410008739A](https://openairdocs.org/incident/20000410008739A), Apr 10, 2000: Spokane, WA, No damage. (-23) During landing roll-out, tail wheel strut, apparently failed. Pilot unable to maintain directional control, a/c entered a ground loop to the left. Right… 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.