CEN13LA212

About 18 months prior to the accident flight, the airplane underwent maintenance to remove and replace both the left and right flaps. While on pattern downwind, the pilot adjusted flaps from up to half, at which time the right flap rod end separated from the right flap actuation fitting. The pilot initiated a climb and struggled to maintain roll control. He briefly adjusted flaps to the up position in an attempt to alleviate the problem, and then adjusted the flaps back to half. The pilot then adjusted the flaps from half to full and the airplane began to roll right due to flap asymmetry, eventually reaching 86 degrees of right bank. The airplane began to stall and the pilot initiated the airplane’s ballistic parachute recovery system about 509 feet above ground level. Subsequently, the airplane descended to the ground with the aid of the parachute and came to rest upright on a frozen lake. A postflight examination of the right flap rod end area revealed the mounting bolt and washer were missing and lying under the airplane. No evidence of a safety wire was present on the mounting bolt or on the right flap actuation fitting. The safety wire was most likely not installed when the right flap was reinstalled and went unnoticed for over 211 hours of operation. During this time there was a subsequent annual inspection at 114 hours prior to the accident and a pre-buy inspection at 101 hours prior to the accident.

**This report was modified on 9/20/2013. Please see the public docket for this accident to view the original report.** On March 29, 2013, about 1045 central daylight time, a Cirrus SR22T airplane, N1967N, was substantially damaged after impact with terrain (frozen lake) near the Chandler Field Airport (AXN), Alexandria, Minnesota. The private pilot and one passenger sustained minor injuries, and two passengers were not injured. The airplane was registered to MWBS Holdings LLC and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 with no flight plan filed. Day visual meteorological conditions prevailed for the flight, which originated from the Marv Skie-Lincoln County Airport (Y14), Tea, South Dakota about 0904. While on pattern downwind to AXN, the pilot reported a loud noise during flap extension. The pilot initiated a climb as he struggled to maintain roll control. He attempted to reduce the airplane’s rolling tendency by adjusting flap position. As his control of the airplane worsened, the pilot pulled the ballistic recovery system handle. The parachute deployed and the airplane descended onto a frozen lake. The flight recording device was recovered from the accident airplane and forwarded to the National Transportation Safety Board’s Vehicle Recorder Laboratory for evaluation. While on pattern downwind, the recorder indicated that the flaps were adjusted from up to half and the airplane made several left bank turns, with a maximum of 30 degrees of left bank. About 18 seconds after initial flap movement, the flaps were briefly adjusted to up and returned to half. About 36 seconds after initial flap movement, the flaps were adjusted from half to full and the airplane began a right roll to a steep right bank attitude. A stall indication was recorded 38 seconds after the flaps were adjusted to full. The Cirrus Airframe Parachute System (CAPS) was deployed two seconds after the stall indication. The CAPS handle pull occurred at a pitch of 22 degrees nose down, a roll attitude of 86 degrees right bank, and an altitude of about 519 feet above ground level. The airplane was examined at the accident site by Federal Aviation Administration (FAA) inspectors and a representative of Cirrus Design Corporation. The right flap rod end was found disconnected from the right flap actuation fitting. The right flap rod end mounting bolt and washer were found lying on the snow under the airplane. No evidence of a safety wire was present on the mounting bolt or on the right flap actuation fitting. An examination of the CAPS Rear Harness assembly revealed that both reefing line cutters had fired but the rear harness remained “snubbed.” The impact scars on the snow and Ice, and the damage to the aircraft indicated that touch-down occurred while the airplane was in a 40-50 degree nose-down attitude. This nose-down attitude is consistent with a touch-down prior to “tail drop.” A review of maintenance records indicated that the rightflap was reinstalled on August 3, 2011, at a Hobbs time of 66.4. According to maintenance manual procedures, the mounting bolt and washer hardware were to be torqued to a measured 50-70 inch pounds, then safety wired to the flap actuation fitting. An annual inspection was conducted on July 10, 2012 (163.9 Hobbs), a pre-buy inspection was conducted on November 5, 2012 (177.2 Hobbs) and the accident occurred with a Hobbs time of 278.0. According to the Cirrus SR22T pilot operating handbook, the preflight checklist states to "inspect flap hinges, actuation arm, bolts, and cotter pins.....secure."