What happened
On 10 January 2017, a Boeing 737-8K5, registration G-FDZY, was performing a commercial passenger flight from Bournemouth Airport. During the takeoff rotation, the left engine ingested a seagull. This impact resulted in an immediate change in engine acoustics and an increase in indicated engine vibration, which was accompanied by light vibrations throughout the airframe. Despite these changes, the crew maintained takeoff thrust, and the engine remained within its operational limits.
After climbing to 4,000 ft, the crew requested to enter a holding pattern at Bournemouth to evaluate the situation and requested a runway inspection. While the aircraft was in level flight, the vibration levels decreased, and the engine appeared to be operating within normal parameters. Following consultations with the aircraft operator, the crew decided to divert to London Gatwick, opting for the longer runway available there.
During the holding period, the crew utilized the time to brief passengers, reduce the aircraft's landing weight through fuel burn, and consult the Quick Reference Handbook. They specifically reviewed the 'High Engine Vibration' checklist to prepare for a potential go-around. Because the vibration levels were observed to increase with higher power settings, the crew elected to perform a precautionary overweight landing using flap 15. The crew also prepared a specific flare technique and a plan to use flap 1 should a go-around become necessary.
Upon initiating the diversion, the crew declared a PAN call and notified Gatwick ATC of their intention to stop on the runway to allow the fire service to inspect the engine and brakes. The landing at Gatwick was completed without incident. Following an external inspection by emergency services, the aircraft taxied to a stand with the left engine shut down.
Findings
- The left engine sustained damage to three fan blades due to the ingestion of a seagull.
- The decision to perform an overweight landing was driven by the observation that increased power settings exacerbated engine vibration.