The Shepherd is a 1976 novel by Frederick Forsyth, but is actually a
well-known Royal Air Force story from considerably earlier.

The Shepherd relates the story of a De Havilland Vampire pilot, going home
on Christmas Eve 1957, whose aircraft suffers a complete electrical failure
over the North Sea en route from Celle in northern Germany to RAF Lakenheath
in Suffolk. Lost in fog and low on fuel, he is shepherded to a disused RAF
dispersal field by the pilot of a De Havilland Mosquito fighter/bomber of
World War II vintage, who has apparently been sent up to guide him in.

When he lands at the base, however, he learns that his saviour was Johnny
Kavanagh, an RAF pilot who guided the pilots of crippled bombers home, who
disappeared over the North Sea in his Mosquito on his last mission, on
Christmas Eve fourteen years before.

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