Complex sentence: The officers allowed for two feet of squat in their calculations, but the NTSB concluded that her squat at that speed and depth would have been between 4.5 and 8 feet.
Split into simpler sentences: The officers allowed for two feet of squat in their calculations. Whereas the NTSB concluded that her squat at that speed and depth would have been between 4.5 and 8 feet.