ED Decision 2009/005/R

The range of masses over which the balloon may be safely operated must be established and at least consists of:

1. Maximum mass.
   
   The maximum mass is the highest mass at which compliance with each applicable requirement of CS-31HB is shown. The maximum mass must be established so that it is not more than the least of: (See AMC 31HB.14(a))
   1. The maximum mass selected for the product;
   2. The design maximum mass, which is the highest mass at which each structural loading condition is shown; or
   3. The maximum mass at which compliance with each applicable flight requirement is shown.
2. Minimum mass.
   
   The minimum mass is the lowest mass at which compliance with each applicable flight

requirement is shown. (See AMC 31HB.14(b))

Mass limitations between which the balloon may be safely operated must be included in the Flight Manual. (See CS 31HB.81(b)(2))

ED Decision 2009/005/R

The maximum mass corresponds to the maximum buoyancy. The lift-producing medium is not part of the maximum mass.

ED Decision 2009/005/R

Minimum mass: In arriving at this figure, especially with larger balloons, attention should be paid to the ability to properly operate the balloon, in terms of both its heating and venting, with the reduced envelope rigidity associated with low mass operation.

→ CS 31HB.16 Empty mass