Courtney: Bomber Command Halifax and Stirling squadrons made attacks on the Tirpitz as far back as January 1942; Halifax and Lancaster units made three further attempts in March and April. The remnants of one of the Halifaxes shot down was recovered from a fjord some years ago and is on display at the RAF Museum, Hendon.
Info on these raids can be found, starting here:
Raids on Tirpitz Spring 1942