Weather radar usage and what not

[Axel]

The smaller your antenna, the worse your resolution.

Paint a ground return at 1.5 X alt. (e.g., FL250 = 37 miles, 10000' = 15 miles). Anything that comes inside the arc of ground return has to be above the ground, therefore it is precip of some kind. Once identified you can examine it more closely.

Raindrops reflect well. Ice crystals do not. Hail reflects best.

You can't see what is in a shadow. Fear of the unknown is healthy.

 

[wms]

Man, you'd be better off posting this question in the weather section, you might get some serious responses...

... I'm sure others can provide better advice than I can if we can get past the sarcasm.

Who was being sarcastic?

 

[BoilerAV8TR]

any of you XJ guys remember the Archie Trammel videos we use to watch in Recurrent. Bout six hours of nap time.
What was it "Add a few knots for mom and the kids."

 

[Coool Hand Luke]

You can either turn the gain down or tilt up until it turns green or goes away thus looking less scarey.

Ok for once heres some serious stuff.

1...take your alt...IE 25000. drop the last 3 zeros so you have 25. Tilt down until the radar is painting ground from 25 miles away to the rest of the screen. Look at that tilt angle (usually round -4ish) now tilt up 6 degrees (+2ish) Pretty much everything that is painting now is probably wx. If you want the bottom of the radar beam to be even with the bottom of your A/C then tilt up an extra 4 degrees (+6ish).

2. If you are in the FL's then you might have to tilt down to get a better look at a storm. It might paint green cause you're high and its all ice. Tilt down and it might turn red and you will know if you want to avoid it or not.

3. Generally below 10,000 or so if you are picking something up with the tilt above 6 degrees or so you can pretty much bet its wx.

4. If you are painting a storm you can use a few tricks to see if its really that bad. One trick is to turn the gain down and see how low the gain goes before it turns green or disappears...the lower gain that paints something the stronger the storm is. (on a side note in the winter snow doesn't really paint that good so you can turn the gain up so see snow showers)

5. Look for shadows. If you see a storm on the radar tilt down until you paint ground just in front of the storm. If no ground gets painted behind the storm...(black "shadow" behind the storm) then it is a strong storm and you should avoid it. Plus that storm is blocking your radar so it could be hiding another storm behind it.

Forgot you asked about range too. It seems to me that anything thats 100 miles or more form the a/c makes the radar pretty much useless. When you want to look at the route a few mins ahead you might have to switch from 50 to 100 mile range to get the "big plan" when you are close the 5, 12, or 25 mile ranges are good to pick you way through holes.

Another thing to remember is that most storms aren't really that big and are just a few miles around so if you have your radar on long range they might show up as a speck that could be easily missed when you look at the radar.

Those are most of the tricks I know. Hope they help you out.

Nice...but: Those numbers are all based on what size your radar dish is. They will be different depending on if you have 12", 14", 16", 18"

 

[time builder]

Who was being sarcastic?

All those people on your "ignore" list probably.

Thanks for the serious responses guys, keep 'em coming.

 

[EBE]

http://www.gapan.org/Papers/Weather Radar.pdf

 

[91100 100 set]

Find true "zero tilt" first. I think this was discussed above, but in any case remember that what the display says is zero tilt may be off a little bit. From there, the best tip I can offer is this. For every 10 miles of range, every degree of radar beam is about 1000 feet of vertical display. So if you're looking at a return at say 30 miles, and you're using a tilt setting of 4 degrees, that return is about 12,000 feet above your current altitude. But remember, most radar sets (at least the ones I've used, have a beam thickness of 8 to 12 degrees. So at that same 30 mile range, your radar beam has spread out to quite a large vertical area, and the farther out you're looking, the less handy this rule becomes.

 

[great cornholio]

Nice...but: Those numbers are all based on what size your radar dish is. They will be different depending on if you have 12", 14", 16", 18"

Thats a good point and is why I said "ish" for the numbers. I figured he was asking around because he was flying for some sort of regional. The numbers I said seem to work pretty good in the 1900 J41 and EMB 145.

I saw on here that someone said that the radar on their plane sucks because you have to use to tilt and gain to really see whats going on. Well for me that seems to be the case with every radar. The only way to really know what you are looking at is to use the tilt and gain to see what is actually going on. If you dont use the tilt and gain to investigate you can end up deviating around a city or coast line...or you could end up flying into a "green" echo that is really a bad mama jama tornodo throwin out trailer park killin storm.

 

[airksk]

If possible, experiment on a day when you have good visual on storms. One isolated cell at 10 o'clock, tilt radar and play with gain until said cell shows up. This will give you a feel for different tilts and gains at different altitudes. If you're diving straight into embedded storms, let the other guy show you their technique.

 

[SLUF4]

someone earlier said that hail is most reflective, but I think this is a common misconception. I'm not an expert or anything but to sum up from our basic indoc book it says, "it should be noted that frozen precipitation is not very reflective of radar energy. The X-band frequencies are optimized for liquid precipitation. This poses 2 problems-Painting liquid vs. frozen heights of a thunderstorm and hail shaft detection." This is why you may fly under an anvil and get yourself into a hail shaft if you aren't careful.