# NTSB DEN00LA081: Hutchins RV4, N724CF, Los Alamos, NM, April 28, 2000 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 28, 2000, 11:00 local (17:00 UTC) - Place: Los Alamos, NM - Coordinates: 35.890464, -106.280372 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.8905&lon=-106.2804&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 8, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 49089 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN00LA081 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/49089/pdf - Page: https://openairdocs.org/ntsb/DEN00LA081 ## Probable cause The pilot's failure to maintain control of the aircraft after initiating a go-around following a hard bounced landing. Factors were variable shifting winds and a high-density altitude. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Hard landing, landing - flare/touchdown - weather condition - variable wind (contributing factor) - weather condition - sudden windshift (contributing factor) - weather condition - high density altitude (contributing factor) - aborted landing - initiated, pilot in command - In flight collision with terrain/water, landing - aborted - terrain condition - loose gravel/sandy - aircraft control - not maintained, pilot in command (cause) ## Analysis During approach for landing at the completion of a cross-country flight, the pilot noted the UNICOM reported the wind was calm but the windsock stuck straight out. During the landing attempt, the aircraft bounced and as it departed the side of the runway into dirt the pilot attempted to abort the landing. After a climb was initiated, a steep bank was made to avoid striking the airport perimeter fence. The aircraft then settled, in a wings level attitude, onto the ground causing the main landing gear to collapse and substantial damage to the airframe. The pilot reported the wind as variable at 10 knots with no gusts. Density altitude at the time was approximately 9,600 feet. ## Factual narrative On April 28, 2000, at 1100 mountain daylight time, a Hutchins RV4, N724CF, sustained substantial damage when it impacted the ground during an aborted landing on runway 27 at Los Alamos, New Mexico. The commercial pilot/flight instructor, the sole occupant was not injured. The flight was a cross-country flight that originated from Pagosa Springs, Colorado, and was operating under the provisions of Title 14 CFR Part 91. Visual meteorological conditions prevailed and no flight plan was filed. During impact, the main landing gear collapsed, the firewall was damaged, and the propeller was damaged. The propeller bore chordwise damage and aft bending of both blades. Pictures provided by the Federal Aviation Administration Airworthiness inspector who examined the aircraft depicted both propeller blades to be in a "feathered" position. The type of propeller installed cannot be placed in a feathered position by pilot input from the cockpit. According to the pilot, the UNICOM reported the wind to be calm, but the windsock was "standing straight out." The pilot said she landed "harder than normal, bounced, and came down a second time and the airplane started to veer to the left." In her statement, she said when she "hit the dirt", she applied full power, climbed, and made a steep turn to avoid hitting the chain link fence which separates the airport from the highway. When above the fence, with wings level, she said the airplane was "slammed" to the ground. In her accident report, the pilot indicated the wind direction was variable at 10 knots. She did not indicate that gusts were present. According to the pilot, the temperature was approximately 75 degrees Fahrenheit. The airport elevation is 7,171 feet above mean sea level. Using the above figures, the density altitude was calculated to be approximately 9,600 feet. According to the airport manager and information provided by the pilot, winds at Los Alamos can vary from one part of the runway to another. A review of Safety Board records provided only one previous accident with wind as a factor. Wind was not listed as a cause on any previous accident at the airport. After the accident, the owner took the propeller to New Mexico Propeller, Inc., where it was disassembled. The propeller shop reported that the pitch change rod was broken internally on both sides of the fork. According to information provided by Hartzell Propellers, this type of damage is a common finding following a hard impact of the propeller. It occurs when one blade is forced to change pitch without the "cooperation" of the other parts. According to Hartzell, this forces the pitch change rod into a "Z" shape that fractures the rod on both sides of the fork. This condition is not unusual and is the result of impact damage. Hartzell engineering said that "no pitch change rod failures have been reported on this type propeller," and no failures have ever been reported that resulted in a "-1" compact propeller going to an extreme high blade angle greater than the high pitch stop in flight. ## Aircraft - Registration: [N724CF](https://openairdocs.org/aircraft/N724CF), registered now, S/N 724 (OpenAirDocs) - Reported make and model: HUTCHINS RV4 - Registry model: [Hutchins Frank RV-4](https://openairdocs.org/model/hutchins-frank-rv-4) (registry code 05608HB) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 724 - Airframe hours: 500 - Engines: Lycoming O-320-D3G 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Marilyn J. Hutchins - Registered owner: Charles F. Hutchins - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, July 1, 1999, 20 hours before - Departed: 2V1, PAGOSA SPRINGS, CO - Destination: LAM, NM - Airport: LAM, Los Alamos, runway 27, 5,550 × 113 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 59; commercial, flight instructor; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 3,000 total, 135 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 10 knots - Lowest ceiling: none - Temperature: 75 °F ## 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 20000428011409A](https://openairdocs.org/incident/20000428011409A), Apr 28, 2000: Amtr RV4, Los Alamos, NM, Substantial damage. (-23) On April 28, 2000, at approx. 1130 MDT, N724CF, an RV-4 , ost control on alnding at the Los Alamos Airport, Los Alamos, NM. The a/c was piloted by… 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.