KnowraAerostatAerostatAn aircraft kept aloft by buoyancy from a gas lighter than air. Balloons and airships are aerostats.BriefConnectBuoyancy: The upward force exerted by a fluid on an immersed object, equal to the weight of displaced fluid. An aerostat rises when displaced air weighs more than the craft and its lifting gas.Lighter-than-air aircraft: Aircraft that obtain lift primarily from buoyancy rather than from aerodynamic forces on wings. Aerostats belong to this broader class of aircraft.Montgolfier brothers: Joseph-Michel and Jacques-Étienne Montgolfier, French inventors associated with the first public hot-air balloon flights. Their demonstrations launched the era of manned aerostatic flight.Weather balloon: An uncrewed balloon that carries instruments into the atmosphere to measure weather conditions. It uses buoyant ascent to collect measurements through the atmosphere.Fixed-wing aircraft: An aircraft whose wings remain stationary relative to the fuselage and generate lift as it moves through air. It needs forward motion to produce wing lift, rather than a lifting gas.Archimedes' principle: The rule that a body immersed in a fluid experiences an upward force equal to the weight of fluid it displaces. It quantifies the lift available to an aerostat in air.Hot-air balloon: A balloon that gains buoyancy by heating the air inside its envelope, making it less dense than outside air. It uses heated air rather than a separate lifting gas.Jacques Charles: French scientist who organized the first hydrogen balloon flight in 1783. His hydrogen balloon demonstrated a different route to buoyant lift.Tethered balloon: A balloon secured to the ground by a cable, commonly used for observation or communications equipment. A tether keeps an aerostat over a chosen location.Helicopter: A rotorcraft whose powered rotating blades generate lift and allow vertical takeoff and landing. Rotor lift permits hovering without buoyant gas.Show all 24Linked from 2 pagesShow all 2