Vaisala Weather Phenomenon Sensor FS11P


The Vaisala Weather Phenomenon Sensor FS11P is designed for demanding weather applications, such as Runway Visual Range (RVR), aviation visibility and weather visibility, as well as current weather observations. It is an ideal combination of accuracy and reliability, a wide measurement range, and low maintenance requirements.



Advantages

- Integrates RVR, visibility, and weather phenomena in one unit

- Extensively proven forward scatter RVR sensor

- Visibility sensor selected and used by the FAA

- Complies with FAA and ICAO specifications

- Suitable for both aviation and weather visibility applications

- Low maintenance requirements

- Compatible with FD12P

- Meets ICAO frangibility standards



Features

- Window contamination correction

- Utilizes the same principles as the FD12P weather sensor

- Accurate and traceable forward scatter measurement

- Technical design and high-power heating compliant with FAA guidelines

- Brittle composite fiber wind mast



Scientifically valid calibration chain

The FS11P is calibrated through a scientifically valid reference chain. The scatter response of the calibration device can be clearly traced back to a reference FS11P visibility sensor, which operates continuously at the Vaisala outdoor test site alongside reference atmospheric transmissometers and other instruments. The visibility measurements of the FS11P are also traceable to FAA reference sensors.

Minimal maintenance requirements

The FS11P employs technology that measures and compensates for window contamination. It ensures measurement accuracy between window cleanings and significantly extends the intervals between cleanings. This system operates by monitoring the total reflectivity of the window surface, automatically compensating for visibility measurement errors caused by contamination. Sophisticated self-testing and modular design allow for very short service times. The visibility measurement fork, current weather detector, and optional background luminance meter are independent instruments that can be quickly replaced as pre-calibrated spare parts.

Reliable operation in severe weather

The FS11P integrates four main design features to ensure reliable operation even in harsh weather conditions. The first is window contamination compensation technology. The second is the "downward-looking geometry" design of the optical probes, which protects them from wind-blown particles, including horizontally flying particles. The third is the high-power heater. Each heater has its own temperature monitoring mechanism to prevent snow accumulation even during heavy blizzards. The final feature is the optical path gap monitoring circuit, which ensures measurements are free from obstructions.

Technical compatibility

In addition to technical similarities, the FS11P is compatible with the FD12P and can therefore be used as a replacement for the FD12P. Both offer the same mechanical, electrical, and communication interfaces and transmit data in similar information formats widely used in aviation and meteorological fields.