Casualties unknown

2005-02-07: Cirrus Design Corp SR22 G2 (N286CD) — Norden, CA

Norden, CA, US

On February 7, 2005, a Cirrus Design Corp SR22 G2 (registration N286CD) was involved in an aviation accident near Norden, CA. Investigators recorded the probable cause as: the pilot's in-flight loss of control following an inadvertent encounter with unforecast severe icing conditions. A factor in the accident was the inaccurate icing forecast developed by the NWS Aviation Weather Center. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

An IFR flight encountered severe icing, leading to an uncontrolled descent and ground collision. The aircraft was not certified for known ice, and the ballistic parachute deployed outside its envelope.

History of Flight

The airplane was operating under an instrument flight rules (IFR) flight plan. After encountering icing conditions, the aircraft departed from controlled flight, entered an uncontrolled descent, and collided with the ground. The airplane was equipped with an Ice Protection System that supplied deicing fluid to the wings, tail, and propeller when activated. However, the aircraft was not certified for flight into known icing, and the Pilot Operating Handbook stated that "Flight into known icing conditions is prohibited."

Preflight and Weather Briefing

The pilot received a preflight weather briefing, which advised that there were no pilot weather reports (PIREP) for the intended route, and that the freezing level in the Reno area was 6,000 feet with no precipitation. There were no valid SIGMETs or AIRMETs for icing conditions along the route. The pilot filed his IFR flight plan for 12,000 feet but indicated he might request 14,000 feet once airborne.

In-Flight Communications

After takeoff at 1807:46, the pilot contacted Oakland Air Route Traffic Control Center (ARTCC) and requested to climb to 16,000 feet to try to get above the clouds. At 1813:40, he reported still being in the clouds and asked about going lower. At 1815:00, he advised ARTCC that if he could go up another 200-300 feet, he could get above the clouds. When asked for clarification, the pilot stated he wanted to go up first to build up airspeed. He was cleared for a block altitude between 16,000 and 17,000 feet. About two minutes later, he transmitted that he was "coming down" and icing up. The last transmission at 1817:42 again indicated icing and descent.

Ballistic Parachute System

Investigators from Ballistic Recovery Systems (BRS) examined the ballistic parachute system and determined it was deployed outside the system's operating envelope of 133 knots indicated airspeed.

Wreckage and Mechanical Examination

An examination of the airplane wreckage revealed no evidence of preimpact mechanical failures or malfunctions.

Weather Analysis

Analysis of the actual weather conditions encountered indicated the likelihood that the pilot encountered severe icing related to super-cooled large water droplets as the aircraft reached 16,000 feet and above. Review of the weather forecast products available at the time of the pilot's briefing disclosed that the AFSS briefing fully conformed to Federal Aviation Administration standards and adequately covered the observed and forecast weather conditions. Although post-accident analysis showed a clear likelihood of severe icing, the algorithms used by the NWS Aviation Weather Center to predict icing conditions showed only a low probability of icing in the area, and, in the absence of PIREPs to the contrary, an icing forecast was not triggered.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20050222X00211. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.