What happened
On September 14, 2024, a Cirrus SF50, registration N442CV, was on approach to Austin Bergstrom International Airport (AUS) in Austin, Texas, when the aircraft was struck by an unknown object. The flight originated from Cincinnati Municipal Airport/Lunken Field (LUK) in Ohio under visual meteorological conditions (VMC) with a visibility of 10 statute miles and winds from 200 degrees at 10 knots.
While the pilot initially believed a bird had struck the right windscreen and damaged an interior sun visor, manufacturer photographs later revealed scraping and blue, red, and white color transfer marks extending diagonally across the windscreen. The pilot also noted an oily residue on the windscreen following the event, though no samples were retained.
Following the impact, the aircraft's Emergency Autoland (EA) system activated twice without command. Data from the central maintenance computer showed that at 1248 central daylight time, while at approximately 1,540 feet above ground level and traveling at 167 knots, an "Emergency Autoland Activating" warning appeared for 10 seconds, followed by 10 seconds of EA activation. Approximately 4 to 5 seconds after the first deactivation, the warning appeared a second time for 10 seconds, followed by a second activation lasting 9 seconds.
There were no injuries and no fatalities resulting from this incident. The pilot was able to land the aircraft uneventfully at AUS.
The investigation
Data files from the aircraft's on-board Recoverable Data Module were downloaded by the airframe manufacturer and provided to the NTSB. The investigation involves the Federal Aviation Administration and Cirrus Aircraft.