US safety regulators have mandated the inspection of seat fixtures on 36,000 single- and twin-engined Cessna aircraft at an estimated overall cost of more than $3 million.

The Federal Aviation Administration estimates that the checks will cost $85 per aircraft, while replacement of seat rails, seat-roller kits, and miscellaneous parts could cost up to $775 per aircraft.

The new airworthiness directive has been prompted by reports of crew seats slipping when the primary latch pin was not properly engaged in the seat rail (or track) and reports of seat roller housings departing from the rail, according to the FAA.

The directive aims to prevent such slippage or departure, which can prevent a crew member from reaching all the controls and could lead to loss of control.

Seats on all examples of more than 220 variants of 18 different piston-powered Cessna models must be checked within 100 flying hours (or 12 months, whichever comes first). The affected designs are Cessna Models 150, 152, 170, 172, 175, 177, 180, 182, 185, 188, 190, 195, 206, 207, 210, T303, 336, and 337.

The repetitive inspections and possible replacement of parts cover many aspects of the seat structure and mounting, including axle bolts, lock-pin springs, pin engagement, rails, rollers, roller-housing wall thickness, tangs, and washers.

Source: Flight International