Incident Overview
On 18 January 1998 at 1429 UTC, a Jetstream 4100, registration G-MAJA, experienced a lightning strike while descending toward Jersey after a flight from Cardiff. The aircraft was at flight level 60 near the northeastern corner of Sark, Channel Islands. The crew reported a bright flash and loud bang. The right engine generator went offline, and the left engine overheat warning activated. The generator was reset, and the overheat warning checklist was performed. Airspeed was reduced to 140 knots as a precaution against structural damage. The captain addressed passengers, and the flight continued with an uneventful approach to Jersey, though aileron control felt less effective than normal, possibly due to strong wind and turbulence.
Aircraft and Crew
G-MAJA was a 1994 Jetstream 4100 powered by two TPE 331-14R-802H turboprop engines. The three-person crew and twelve passengers were uninjured. The commander, aged 55, held an Airline Transport Pilot's Licence with 12,540 total flying hours, including 3,900 hours on type. He had flown 130 hours in the previous 90 days and 50 hours in the last 28 days.
Weather Conditions
At the time of the incident, the outside air temperature was +2°C. The aircraft was clear of cloud and flying in moderate rain. Weather radar was set to the 10-mile range and 10 degrees up, with lightning detectors active. Although numerous cumulonimbus clouds were in the area and had been avoided, no returns appeared on the weather radar at the moment of the strike. Recorded meteorological data from the Meteorological Office showed that the nearest lightning discharges within a three-minute window around the strike were at least 70 nautical miles away. A separate diagram covering 46 minutes ending 30 minutes before the strike indicated a concentration of discharges near the Channel Islands and Cherbourg Peninsula.
Damage and Aftermath
Post-flight inspection revealed structural damage to the fin and right aileron, small punctures in the pressure hull skin near the nose, and the fire-detection and propeller de-icing systems were rendered inoperative. The crew noted the damage after leaving the aircraft. The aircraft was equipped with a lightning detection and mapping system, which displayed lightning discharge data on the weather radar screen alongside conventional weather information. The system's effectiveness in preventing strikes is unknown; the source notes that such systems are historical rather than predictive and cannot avoid strikes triggered by the aircraft's passage.
Meteorological Analysis
Examination of radar and communications data showed changes in descent rate, ground speed, and heading approximately 30 seconds before the crew reported the strike, placing the aircraft at just under 6,000 feet near Sark. The Meteorological Office's lightning detection system does not guarantee recording all discharges; the strike on G-MAJA was not recorded despite lightning activity in the area during the previous hour and ten minutes. The source suggests that residual lightning potential may have remained after an active storm, and the aircraft's passage initiated a low-power discharge. Similar winter lightning strikes over open sea have occurred at outside air temperatures near 0°C.