Robbe - Futaba True Airspeed Sensor 450 # F1677

True Airspeed Sensor 450

Measure the exact speed. The robbe-Futaba True Airspeed Sensor 450 for the S.BUS system provides an exact measurement of the model's speed through the air by accurately monitoring the dynamic and ambient air pressure.

The dynamic air pressure (caused by the model's airspeed) is measured by what is known as a Prandtl tube, and the differential pressure is measured by additional annular jets. The special construction of the jets reduces the system's sensitivity to fluctuations in pressure and airflow in the model's fuselage. The net result is that the model's actual speed is measured compared with the surrounding air. The dynamic and differential pressure are fed to the digital pressure sensor in the electronics box via two thin silicone hoses. From this data a micro-processor calculates the model's airspeed relative to the air. The data is then passed to the receiver via the S.BUS2 interface, and from there to the transmitter's integral screen. Since air pressure varies according to the height of the flying site above mean sea level it is also necessary to "zero" the sensor to the altitude of the flying site in order to obtain accurate speed measurements. This is accomplished very conveniently by pressing the Reset button on the electronics box. For simplicity of operation this button can also be accessed remotely via an external switch in the model, as a socket is available for this purpose. Since the True Airspeed measurement of speed is so accurate, it can be exploited for such purposes as checking the critical minimum approach speed, in order to prevent the model stalling on the landing approach due to insufficient speed.
 

Specification
Dimensions
Electronics box: 25 x 25 x 15 mm
Weight: approx. 12 g
Prandtl tube: D 4 x 65 mm
Weight: approx. 4 g
Measurement range: approx. 30…450 km/h