Items Placed On Glare Shield Of Particular Interest

An event aboard a Mitsubishi MU-2B has prompted the FAA to issue a Special Airworthiness Information Bulletin (SAIB) concerning the potential hazards and airworthiness concerns related to having loose equipment in the flight compartment; particularly items placed on the glare shield. It applies to all aircraft that have a glare shield installed above the instrument panel, and is of particular concern to aircraft with windshield heating systems where the power terminal strips may be exposed and subject to an electrical short from a foreign object placed on the glare shield.

During recent flight, thick black smoke filled the cockpit of a Mitsubishi MU-2B, and the crew was forced to make an emergency landing. It was discovered that a hand-held GPS receiver and antenna had been set on the glare shield. A metallic portion of the GPS antenna inadvertently made contact across the windshield heater terminal strips, resulting in an electrical short circuit. The resulting current flow caused the loose equipment to burn, resulting in smoke in the cockpit.

The FAA says that loose equipment on the glare shield or in the cockpit can present a hazard, particularly for aircraft with a windshield heater system installed where electrical terminal strips may be exposed and subject to short circuit. Owners and operators should recognize the potential for exposed terminal strips to be attached to high current windshield heating systems and refrain from placing any loose items on the glare shield that might cause an electrical short and subsequent electrical fire. If possible, these terminal strips should also be insulated or covered to mitigate such an occurrence.

The FAA also reminds owners and operators that loose or portable equipment on the glare shield can obscure the field of view of the crew, can potentially influence the magnetic compass accuracy, and can become a hazard in turbulence. Loose or portable items and equipment should be properly secured prior to and during the flight, portable or loose equipment should be isolated from other equipment installed, and the magnetic compass should be checked to assure it is not being affected by any magnetic or electrical influence from portable or loose equipment.

FMI: www.faa.gov