Section 29.753 - Main float design(a)Bag floats. Each bag float must be designed to withstand-(1) The maximum pressure differential that might be developed at the maximum altitude for which certification with that float is requested; and(2) The vertical loads prescribed in § 29.521(a) , distributed along the length of the bag over three-quarters of its projected area.(b)Rigid floats. Each rigid float must be able to withstand the vertical, horizontal, and side loads prescribed in § 29.521 . An appropriate load distribution under critical conditions must be used.