A system for controlling an operating mode of an airship, comprising: a sensor system configured to determine an altitude of a bottom of a hull of the airship, the hull configured to be inflated with a lighter-than-air gas; and a computer processor configured to execute logic instructions to: determine the altitude of the airship based on information from the sensor system; determine an operating mode of the airship; determine whether to increase, decrease or maintain the altitude and airspeed of the airship based on the operating mode; and generate signals to open or close a valve and operate a ballonet fan to control gas pressure within the hull and a ballonet enclosed in the hull of the airship based on a desired airspeed, altitude, and operating mode, characterised in that the valve is coupled between a plenum chamber of an air cushion landing system (ACLS) and the ballonet, the plenum chamber is formed by a landing surface and the ACLS when the ACLS is in contact with the landing surface, the generated signals controlling the valve to selectively allow air to flow from the plenum chamber into the ballonet while the ACLS is in contact with the landing surface, the generated signals further controlling the ballonet fan to draw air into the ballonet. a sensor system configured to determine an altitude of a bottom of a hull of the airship, the hull configured to be inflated with a lighter-than-air gas; and a computer processor configured to execute logic instructions to: determine the altitude of the airship based on information from the sensor system; determine an operating mode of the airship; determine whether to increase, decrease or maintain the altitude and airspeed of the airship based on the operating mode; and generate signals to open or close a valve and operate a ballonet fan to control gas pressure within the hull and a ballonet enclosed in the hull of the airship based on a desired airspeed, altitude, and operating mode, characterised in that the valve is coupled between a plenum chamber of an air cushion landing system (ACLS) and the ballonet, the plenum chamber is formed by a landing surface and the ACLS when the ACLS is in contact with the landing surface, the generated signals controlling the valve to selectively allow air to flow from the plenum chamber into the ballonet while the ACLS is in contact with the landing surface, the generated signals further controlling the ballonet fan to draw air into the ballonet. determine the altitude of the airship based on information from the sensor system; determine an operating mode of the airship; determine whether to increase, decrease or maintain the altitude and airspeed of the airship based on the operating mode; and generate signals to open or close a valve and operate a ballonet fan to control gas pressure within the hull and a ballonet enclosed in the hull of the airship based on a desired airspeed, altitude, and operating mode, characterised in that the valve is coupled between a plenum chamber of an air cushion landing system (ACLS) and the ballonet, the plenum chamber is formed by a landing surface and the ACLS when the ACLS is in contact with the landing surface, the generated signals controlling the valve to selectively allow air to flow from the plenum chamber into the ballonet while the ACLS is in contact with the landing surface, the generated signals further controlling the ballonet fan to draw air into the ballonet.