Incident Description
A flight crew descending from FL 350 for an IFR arrival to New Orleans observed green and yellow returns on weather radar with isolated red cells to the left and right of the intended flight path. Before entering clouds at 30,000 feet, the captain selected continuous engine ignition and activated the engine anti-ice system. The crew chose a route between two cells displayed as red on the weather radar.
Weather Encounter
Heavy rain, hail, and turbulence were encountered. At approximately 16,500 feet, both engines flamed out.
Engine Failure and Recovery
The auxiliary power unit (APU) was started and AC electrical power was restored while descending through about 10,600 feet. Attempts to windmill restart the engines were unsuccessful. Both engines lit off using starters, but neither would accelerate to idle; advancing thrust levers increased exhaust gas temperature (EGT) beyond limits. The engines were shut down to avoid catastrophic failure.
Emergency Landing
An emergency landing was made on a levee without further damage to the aircraft.
Investigation Findings
Investigation revealed the aircraft encountered a Level 4 thunderstorm, but the engines flamed out despite meeting FAA specifications for water ingestion. The aircraft sustained minor hail damage; the #2 engine was damaged from overtemperature.
Post-Incident Actions
After the incident, OMB 88-5 and AD 6-14-88 were issued to require a minimum RPM of 45% and to restrict the use of autothrust in moderate/heavy precipitation. An engine modification was provided for increased capacity of water ingestion.