# NTSB DFW08CA048: Portman RV-7A, N131RV, ELmendorf, TX, December 21, 2007 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: December 21, 2007, 16:30 local (22:30 UTC) - Place: ELmendorf, TX - Coordinates: 29.268333, -98.334999 - Nearby events: https://openairdocs.org/map.md?lat=29.2683&lon=-98.3350&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report February 28, 2008 - Report: Approved by Office Director - Parties: FAA FSDO - NTSB case key (mKey): 67291 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW08CA048 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67291/pdf - Page: https://openairdocs.org/ntsb/DFW08CA048 ## Probable cause The failure of the nose landing gear. A contributing factor was the mound/uneven runway surface. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - On ground/water encounter with terrain/water, landing - roll - terrain condition - rough/uneven (contributing factor) - Nose gear collapsed, landing - roll - landing gear,nose gear strut - buckled (cause) - Nose over, landing ## Analysis The private pilot landed his single-engine tricycle gear homebuilt airplane at a private 2,600-foot long by 200-foot wide grass airstrip. The pilot reported that on approach the airplane had about a 25-degrees of flap setting; he then "slowed [the airplane] to 80 knots on final [and crossed] over the fence at 70-75 knots." The pilot added, he made a normal landing and held the aircraft's nosewheel off the surface of the runway, until the airspeed bled off. About halfway down the runway, he stated that the airplane's nose suddenly lifted to about a 25-30 degree angle and when the nose came back down, he felt a "shutter". After the nosewheel came in contact with the runway surface, the aircraft tipped forward and while at a very slow speed, flipped over. The aircraft came to rest in the inverted position. The pilot inspected the runway and reported that about 66-feet from the aircraft, it appeared the nosewheel contacted the side of a "gopher mound" which caused the aircraft's nose to elevate. About 36-feet from the mound, and about 6-feet from where the nosewheel contacted the surface, the nosewheel track showed signs of widening. The wheel track got progressively wider and deeper until the point where the aircraft overturns. The aircraft had not been modified with the kit manufacturer's service bulletin, which increased the nose fork axle-to-ground clearance; the pilot added that he didn't think the added clearance would have helped prevent the accident. ## Factual narrative The private pilot landed his single-engine tricycle gear homebuilt airplane at a private 2,600-foot long by 200-foot wide grass airstrip. The pilot reported, on approach the airplane had about a 25-degrees of flap setting; he then "slowed [the airplane] to 80 knots on final [and crossed] over the fence at 70-75 knots." The pilot added, he made a normal landing and held the aircraft's nose wheel off the surface of the runway, until the airspeed bled off. About halfway down the runway, he stated that the airplane's nose suddenly lifted to about a 25-30 degree angle and when the nose came back down, he felt a "shutter". After the nose wheel came in contact with the runway surface, the aircraft tipped forward and while at a very slow speed, flipped over. The aircraft came to rest in the inverted position. The pilot inspected the runway and reported that about 66-feet from the aircraft, it appeared the nose wheel contacted the side of a "gopher mound" which caused the aircraft's nose to elevate. About 36-feet from the mound, and about 6-feet from where the nose wheel contacted the surface, the nose wheel track showed signs of widening. The wheel track got progressively wider and deeper until the point where the aircraft overturns. The aircraft had not been modified with the kit manufacturer's service bulletin, which increased the nose fork axle-to-ground clearance; the pilot added that he didn't think the added clearance would have helped prevent the accident. ## Aircraft - Registration: [N131RV](https://openairdocs.org/aircraft/N131RV), registered now, S/N 70327, built 2007 (OpenAirDocs) - Reported make and model: Portman RV-7A - Registry model: [Portman Joseph Louis III PORTMAN RV-7A](https://openairdocs.org/model/portman-joseph-louis-iii-portman-rv-7a) (registry code 05614VP) (OpenAirDocs) - Registry engine: [Lycoming IO-360-A1B6](https://openairdocs.org/engine/lycoming-io-360-a1b6) (registry code 41576, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 70327 - Airframe hours: 290 - Engines: Lycoming IO-360 reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, March 1, 2007 - Departed: EYQ, HOUSTON, TX - Destination: 28TE, Elmendorf, TX - Airport: 28TE, Elmendorf, runway 17, 2,600 × 200 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review May 1, 2006; seat: left; flight hours: 1,050 total, 290 in this make and model, 990 as pilot in command, 107 in the last 90 days, 32 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 37 °F - Altimeter: 29.80 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 20071221829229A](https://openairdocs.org/incident/20071221829229A), Dec 21, 2007: Portma PORTMANRV7A, Elmendorf, TX, Substantial damage. (-23) On 12-21-07 an RV7 piloted by [privacy data omitted] was landing on a grass field at his home base. After touchdown, the roll out was accomplished with… 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.