The airworthiness directive was issued early Monday, and calls for airlines to replace some of the pins used in the tails of the
The protective surface coating that attaches the pins to the horizontal rear spar — the fin on the tail of the aircraft that is parallel to the ground — may have been incorrectly applied. If those pins fail, the attachment of the fin to the fuselage would weaken, and the pilot could lose control.
The directive takes effect May 20, and covers some 737,600, 737-700, 737-700C, 737-800, 737-900, and 737-900ER planes.
The FAA expects the mandated changes to cost $9,627 per plane (based on the price of labor and parts), about $10.1 million overall.