OK, it's the 2nd business day of the month and Tour 28 has yet to end...
But I think that this month's winner is probably a shoe-in.
(Although my search method is far from thorough, and less than scientific.)
Ezee!
With 202 hours in the MA and 17 hours in the CT.
That's 219 logged hours total!
Keep in mind that the hours logged on the score pages reflect only flight time. They do not reflect time spent in/as: Tower (including mission planning, mission-start wait time, and chatting on text buffer), ship gunner, TA, SEA, offline, map making, BB, web-site making, chart making, looking at the score page, etc.
You've got to figure that most people spend at least 10% more time than they officially log doing some of the above. That means that Ezee must have really devoted at least 241 hours this month to AH. (Out of 744 hours in a 31 day month,... Yikes!)
Man, I bet his imaginary girl-friend is feeling lonely.

(Sorry dude)

Honorable Mentions go to the following folks who have logged about 190 hours in the MA this Tour:
Zamzi
ab8aac
Ogun
Feel free to add others who may have surpassed Ezee's achievement, or at least deserve an Honorable Mention.
eskimo