B1900D Window Blowout
On 22 October 2018 Federal Airlines Beechcraft B1900D ZS-PHX was in cruise at 20000ft when it suffered an explosive decompression. The aircraft made a safe landing, without injury to the 13 occupants. According to the South African CAA safety investigation report, the decompression was due to the failure of the third cabin window on the right-hand side of the fuselage.
This window was installed in January 2007, approximately 6,000 flying hours earlier. The first two cabin windows on each side of the B1900 are a two-pane. The rest are single-pane windows with a life of 43,600 flight hours or 61,700 pressure cycles.
Laboratory examination revealed that cracking propagated from the outside surface in the centre of the window. The B1900D Aircraft Flight Manual states:
…do not operate the engines with the propellers feathered except during external power starts and propeller feather checks, except that the propellers may be operated in feather at temperatures not to exceed +5°C for a maximum of 3 minutes for the purpose of airframe de-icing.
Beechcraft B1900 Airliner Communiqué no. 30 (issued in December 1993) states:
After a fleet inspection, 8 other windows were rejected in the operators fleet.
The SACAA safety message was that:
It is imperative that operators abide by the B1900 communiqué no. 30 during ground operations to avoid excessively heating the cabin windows.