What is the maximum gross weight for lighter-than-air aircraft?

The maximum gross weight for lighter-than-air aircraft, which includes balloons and airships, is defined by regulatory standards to ensure safety and operational efficiency. The correct answer, indicating 660 lbs as the maximum gross weight, aligns with the limitations set for specific types of lighter-than-air vehicles, particularly for those operating under certain conditions and regulations.

This weight restriction is critical as it takes into account factors such as lift capability, structural integrity, and safety measures for flight operations. Keeping the gross weight at or below this limit helps ensure that the lighter-than-air aircraft can achieve adequate lift and maneuverability, reducing risks associated with overloading, which may lead to operational failures or accidents.

Options categorized with higher weights extend beyond the standard limits defined for certain classifications of lighter-than-air craft typically employed for recreational or specialized uses. Therefore, adhering to the lower weight limit establishes an essential boundary for safe and effective aerodynamics in lighter-than-air aviation.