Superpressure balloon

Definition

• (1) A type of hot air balloon which has no openings to the atmosphere—the mouth is sealed with a special skirt—and is kept pumped full of air (at a higher pressure than the atmosphere) by an on-board fan. Used on moored balloons to allow operations in relatively strong wind.
  (2) In gas ballooning, a sealed envelope in which the internal envelope pressure exceeds that of a non-sealed envelope.

References

• Balloon Flying Handbook, Federal Aviation Administration, 2024