I stumbled across this rather telling list whilst perusing Militaryphotos.net and lifted it, wholesale to share here. I've neglected to cross reference every incident listed here, since I'd already read/heard of several of them. I don't think that this list is necessarily exhaustive either. There are several more similar incidents mentioned in the source thread (read on for link).
-1981 NATO exercise Ocean Venture, an unnamed 1960s vintage Canadian diesel submarine “sank” the carrier USS America without once being itself detected, and a second unidentified vintage sub “sank” the carrier USS Forrestal.
- 1989 exercise Northern Star, Dutch diesel submarine Zwaardvis “sank” carrier USS America.
- RIMPAC 1996, Chilean diesel submarine Simpson “sank” carrier USS Independence.
- 1999 NATO exercise JTFEX/TMDI99 Dutch diesel submarine Walrus “sank” carrier USS Theodore Roosevelt, exercise command ship USS Mount Whitney, one cruiser, several destroyers and frigattes, and Los Angeles class nuclear fast attack submarine USS Boise.
- RIMPAC 2000, Australian Collins class diesel submarine “sank” two US fast attack submarines, and almost “sank” carrier USS Abraham Lincoln.
- 2001 Operation Tandem Thrust, HMAS Waller sank two US amphibious assault ships in water barely deeper than length of submarine itself, though it was later sank herself, and Chilean diesel sub took out Los Angeler class nuclear fast attack sub USS Montpelier twice during exercise runs.
- October 2002, HMAS Sheehan hunted down and “killed” Los Angeles class USS Olympia.
- September 2003, several Collins class submarines “sank” two US fast attack subs and a carrier.
- 2005, Swedish Gotland-class submarine “sank” USS Ronald Reagan.
Here's the thread from whence it came:
http://www.militaryphotos.net/forums...ead.php?244917
Food for thought, eh?