Bag floats. Each bag float must be designed to withstand—
The maximum pressure differential that might be developed at the maximum altitude for which certification with that float is requested; and
The vertical loads prescribed in § 29.521(a), distributed along the length of the bag over three-quarters of its projected area.
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.