Need Advice For My Son USAF

Thank you in advance for your advice. My son has joined the Air Force, though he has not gone to Basic yet. He was approved for a very challenging career known as a TACP (Please see Link - www.globalsecurity.org/.../tacp.htm ) One of the criteria for getting into this particular specialty was to pass the NON-SWIMMING portions of the PAST (Physical Ability Stamina Test - www.afsoc.af.mil/.../pastcriteria.asp ). He was approached today and told that an even more critical need for the USAF was for Combat Controllers, but he would need to also pass the 2 swimming portions of the PAST (see link above, please). Now, he's in great shape, and he can swim like a regular person can swim, but he's NEVER been a swimmer, per se. The question I have is, what should he do in order to prepare to pass the 2 swimming tests: 1) 2 x 20 Meter Underwater Swim: Provide the member 3-minutes of rest between underwaters. If members surface or break the water surface during any portion of the swim, the test will be stopped and considered a failure. 2) 500 Meter Surface Swim (max. time limit 14 minutes for CCT/SOWT; max. time limit 11 minutes 30 seconds for PJ): This swim is conducted using the freestyle, breaststroke or sidestroke. The swim is continuous (non-stop). If a member stops any time during the swim, the test will be stopped and considered a failure for the entire PAST. Sorry for the long message. Any advice will be greatly appreciated.