Luke
249sqn did lose a Canberra around that time, when a B15 flew into a mountian in sardinia (?).
Could have been WJ770. This was a B.16 which crashed into hills in fog at Sinopoli, Calibria, Italy on 11 March 1968 (3K). This is the only Canberra I can find that crashed on or anywhere near Italy or Sardinia.
WJ770
was on 249 but must have been transferred as it was with 6 Sqd at time of crash. Both these sqds were contemporary at Akritori of course.
Pronto
Glad to have been of some help. The current users of
PR.9s - 39Sqd, Marham - took over some of 13Sqd's kites, way back. They may still have engineering records or accounts of incidents in the 9's past, especially if it was a major technical fault. May be worth giving the squadron a call mentioning the a/c numbers, unless any 39ers read this forum and want to contribute.