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One of several small auxiliary gasbags placed inside a balloon or a nonrigid airship that can be inflated or deflated during flight to control and maintain shape and buoyancy.

[French ballonnet, diminutive of ballon, balloon; see balloon.]


(Aeronautics) an air or gas compartment in a balloon or nonrigid airship, used to control buoyancy and shape
[C20: from French ballonnet a little balloon]


(ˌbæl əˈneɪ)

an air or gasbag compartment in a balloon or airship used to control buoyancy and shape.
[1900–05; < French]
References in periodicals archive ?
It uses the existing ballonet fans to inflate and takes under 20 seconds to be ready for use.
To this end, Loon uses balloons that are in fact composed of two envelopes: an outer balloon which contains helium to generate the lift to take it into the stratosphere, and an inner balloon (or ballonet) which can take in or release air in order to modify the altitude once aloft.
A classical airship has various configurations: flabby balloon with ballonet (air chamber), partially inflated and fully inflated (Figure 5).
[13.] Neydorf, R., Novikov, S., and Fedorenko, R., "Continuous-Positional Automatic Ballonet Control System for Airship," SAE Int.
Inside the envelope are two bags of air known as ballonets. Instead of the engine, these ballonets are inflated with helium gas that lifts the blimp into the air or deflated to bring it down.
As a result, before initial departure from home station the amount of air in the ballonets would have to be adjusted to 325 tons of aerostatic lift even if the total gross weight of the vehicle at the time was several times that with cargo and fuel load.