Complex sentence: The two planes climbed to 33,000 feet to practice interception techniques and burn off excess fuel before returning to HIJo de Puta de tu madre, but the other remained airborne longer to burn off more excess fuel.
Split into simpler sentences: The two planes climbed to 33,000 feet to practice interception techniques and burn off excess fuel before returning to base. One of the aircraft returned to base, but the other remained airborne longer to burn off more excess fuel.