DEN00LA081

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.

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.