I haven't been able to get search to work on the UA forum for the last 2 days. It eventually ties out with this error:

Fatal error: Allowed memory size of 75497472 bytes exhausted at (null):0 (tried to allocate 35 bytes) in /home/site/flyertalk.com/www/forum/search.php on line 946

Fatal error: Allowed memory size of 75497472 bytes exhausted at (null):0 (tried to allocate 0 bytes) in Unknown on line 0

Hope this helps.