The Air Force operates the 53rd WRS that has 10 C-130s which they fly directly through the eyewall daily.
http://www.hurricanehunters.com/faq.htm
http://www.hurricanehunters.com/faq.htm
7. Are the aircraft's wings specially reinforced?
Believe it or not, they aren't. Remember that airplanes are built to go very fast through the air, and they don't care if the wind is 5 knots (nautical miles per hour) or 150 knots! As we approach the strongest winds in a hurricane, we simply turn gradually into the wind (called "crabbing") until we punch through into the calm eye.