So, looking at clauses (ii), (iii) and (iv), it tells us that to qualify for TPD, the someone must either loses sight in both eyes, or loses sight on an eye plus loses by severance a limb above wrist or ankle, or loses by severance two limbs above wrist or ankle.
Payload is the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight.Depending on the nature of the flight or mission, the payload of a vehicle may include cargo, passengers, flight crew, munitions, scientific instruments or experiments, or other equipment.Extra fuel, when optionally carried, is also considered part of the payload.hen the weight of the payload and fuel are considered together, it is known as the  useful load fraction . In spacecraft, mass fraction is normally used, which is the ratio of payload to everything else, including the rocket structure.
Definition of payload 1: the load carried by a vehicle exclusive of what is necessary for its operation; especially: the load carried by an aircraft or spacecraft consisting of things (such as passengers or instruments) necessary to the purpose of the flight