Says O2 System Functioned Normally When Checked

Editor's Note: The National Transportation Safety Board has released its preliminary report on a February 2 incident involving a Beechcraft B200 King Air that suffered a cracked windscreen at FL270.

As Aero-News reported, the plane's pilots depressurized the cockpit and put on their oxygen masks, but were unable to begin the flow of oxygen before passing out. Fortunately, the pilots regained consciousness as the aircraft descended, and they were able to land the plane, as the Board notes dryly, "without further incident."

In the report -- which is presented, unedited, below -- the NTSB notes the aircraft's oxygen system operated normally when investigators engaged its controls as defined by the plane's flight manual.

NTSB Identification: CHI07LA063
14 CFR Part 91: General Aviation
Accident occurred Friday, February 02, 2007 in Cape Girardeau, MO
Aircraft: Raytheon Aircraft Company B200, registration: N777AJ
Injuries: 2 Uninjured.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

On February 2, 2007, about 1030 central standard time, a Raytheon Aircraft Company B200, N777AJ, sustained substantial damage during an uncontrolled descent and recovery from cruise at flight level 270. Visual meteorological conditions prevailed at the time of the accident.

The flightcrew reported that they depressurized the airplane after noticing cracking of the airplane windshield. They then donned their oxygen masks but were unable to obtain oxygen from the oxygen system resulting in their loss of consciousness. They later regained consciousness, recovered from the descent, and landed without further incident at Cape Girardeau Regional Airport, Cape Girardeau, Missouri.

The 14 CFR Part 91 flight was operating on an instrument rules flight plan. The pilot and copilot were uninjured. The flight originated from Rogers Municipal Airport-Carter Field, Rogers, Arkansas, at 0939.

On-scene inspection of the airplane noted that approximately 2/3 of the left horizontal stabilizer and elevator were separated from the aircraft and 2/3 of the right elevator was separated but attached at the inboard hinge. The left and right wings were wrinkled. The left pilot windshield outer and inner ply were intact. The inner ply exhibited a shattered appearance with a crack at the lower right hand corner of the windshield. The cabin pressurization dump switch was in the dump position.

The oxygen system worked when it was functionally tested in accordance with Airplane Flight Manual.

(Screen captures of video footage shown on KFVS-12)

FMI: www.ntsb.gov