B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 280; Flight Crew Total 9000; Flight Crew Type 2500
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; General Declared Emergency
Aircraft
The leading edge devices on the starboard side extended at FL340. The cruise mach was .78 and about 270 KIAS. The throttle began to retard to slow to 230 KIAS. We followed the ETOPS procedures taking a 45 degree heading to the north to offset the track by 15 miles. We declared an emergency and coordinated a descent to FL200. At FL200 we executed the QRH procedures which did not resolve the problem. We returned to our departure airport where the Captain made a successful overweight landing. On landing the speed brakes (ground spoilers) were extended manually since they did not deploy. During both the preflight walk around and the post flight check the devices appeared normal on the ground.
No additional information was provided in the secondary narrative.
The flight crew of a B737-800 declared an emergency and returned to their departure airport when the right side leading edge devices extended at FL340.