OK. Made some search and found it.
In 1976 a 747 lost a wing after being hit by lightning.Here a description of the accident;
"
The Boeing was operated on a military logistic flight from Tehran to McGuire AFB via Madrid. The flight took off from Tehran at 08.20h GMT and climbed to a cruising altitude of FL330. After establishing contact with Madrid control, clearance was received to CPL VOR via Castejon. At 14.25h the flight was cleared to FL100. At 14.30 the crew advised Madrid that they were diverting to the left because of thunderstorm activity, and at 14.32 Madrid cleared ULF48 to 5000ft and directed him to contact Madrid approach control. At 14.33 the crew contacted approach control and advised them that there was too much weather activity ahead and requested to be vectored around it. Last radio contact was when ULF48 acknowledged the 260deg heading instructions and informed Madrid that they were descending to 5000ft. The aircraft was later found to have crashed in farmland at 3000ft msl following left wing separation. It appeared that the aircraft had been struck by lightning, entering a forward part of the aircraft and exiting from a static discharger on the left wingtip. The lightning current's conductive path to the static discharger at the tip was through a bond strap along the trailing edge. Concentration of current at the riveted joint between this bond strap and a wing rib were sufficient conductive to cause the flash to reattach to this rivet and to leave the discharger. Fuel vapors in the no.1 fuel tank then ignited. The explosion caused the upper wing skin panel to separate, causing a drastic altering of the aeroelastic properties of the wing, and especially the outboard section of wing. The outer wing began to oscillate, developping loads which caused the high-frequency antenna and outer tip to separate. The whole wing failed a little later."
There was also a 707 from Pan Am in 1963 when he was on an holding close to Philadephia (US).