## Normals

#### Eddie sez:

Photo: Radar controller from the movie Airplane!
Click photo for a larger image

### A Course

I tend to organize things alphabetically; but I know that isn't how you often need information. I also like to tell stories with a beginning, a middle, and an end; but that doesn't work if you want to learning something efficiently. So let's say you have a general understanding of weather radar but would like to become more of an expert. Let me suggest you digest these in the following order:

• How it Works — How a radar determines distance, direction, size, movement, and the depth of a "target."
• Energy — The signal coming out of the radar dish has a level of energy that is sent in a beam and is reflected in varying degrees.
• Beam Width — The width of the energy beam affects more than just its ability to "look inside" of weather systems and will impact how you aim it.
• Attenuation — We are counting on some amount of the beam's energy to be reflected to give us an idea of distance. We are also counting on some of the energy to travel through the weather to give us more information for what lies beyond that first refelction point; this is attenuation. What if all of the beam is attenuated? That is useful too.
• Tilt — Your airplane problem doesn't fly perfectly level to the earth and the angle from the horizon of your radar beam can be affected by the aircraft's angle and altitude. Knowing the tilt and beam width is critical to really understanding where the weather you see on the screen actually is.
• Gain — The "Gain" setting on your radar controller simply changes the focus of the beam, a higher gain narrows the effective beam width. But when you change the gain, you change the nature of the information your radar displays. The "Gain" knob is actually a "calibration" knob and should rarely be touched.
• Calibration — What does green, yellow, red, and purple mean on a weather radar display? Well that depends on its calibration and knowing how is vital to properly using your weather radar.
• Confidence Check — Many aircraft manufacturers provide abbreviated operating manuals for their installed radars and perhaps a few troubleshooting tools. Lacking those, you might try something suggested for the Primus 660.
• REACT — Rain can completely attenuate (absorb) radar energy and mislead you to thinking there is nothing where there is something. The Honeywell Rain Echo Attenuation Compensation Technique (REACT) is used to overcome this. (Or at least try to.)
• Operational Examples — Here are some operational examples of how to properly use your weather radar, as well as links to a few of the more notable accidents.
• Techniques — Perhaps you just need a summary of techniques. Well, here you go.

But if you are looking for something and want to find it quickly, the menu structure above has these items in alphaabetical order and I've duplicated that here:

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