No radar will paint a building thunderstorm unless there is some form of precip coming out somewhere in it. The precip is what gives the radar returns. This appears to have been part of the Air France issue. They flew in between to large cells among a line of severe weather. It looks as if there was no precip in that immediate area in front of them, but that is where the worst updrafts would have been.

You don't have to be in a thunderstorm to get hit by lightning. A lot of precipitation that paints green contains enough static to create a discharge if your aircraft happens to be oppositly charged, especially at or above the freezing level. Frequently "p-static" can be heard over the radios in this situation.

Commonly you'll recieve the same charge as the area around you, but occasionally, you'll transit to another area that has an opposite charge and generate the discharge before the two oppositely charged areas do it by themselves.

Lightning can be frequently found well outside areas of moderate of heavy precip when in TRW environments.

If you start hearing the static building up on the radios it helps to slow down. reducing the speed reduces the friction and the build up of the charge. ive heard that bombardier figured this out with the dash years ago and its worked on the 145 and 170 for me.

Lack of proper training on use of weather radar maybe. Looking at FlightAware makes it look like it may have been just that...pilot error. We'll see.

It is terrible. I fly around at gain +2 and +2 degrees tilt (FL300) just to see anything. And you can't see anything beyond 80 miles. Unless it's huge, you can't see it beyond 40 miles.

And having said that, why would they fly through that cell? It looks like they were heading right for the middle of it then turned toward the edge at the last minute. I'd say they cut it too close.

There's a lot of pilots out there whose motto is "don't be late, penetrate". I hope the AF accident shows people why you give storms a wide berth.

Correct.........this has been well known for many years. It also improves the effectiveness of the static wicks as well, although in the 145 with its many pointy extemeties, it remains a problem.

I can reduce it somewhat by slowing below about 270, which is something to do in moderate bumps anyway and fast enough to usually keep ATC happy.

Also the freezing level is the best place to generate static and also among the higher risks for taking a lightning strike, so I try to avoid prolonged exposure if possible when operating near areas of convective weather.

I haven't had too much problem with the EMB radar (8000+ hours). At first, I felt it had some issues, but the only issue that remain is its greater susceptability for attenuation. In anything greater then light precip, its effectiveness is greatly reduced more so then mainline aircraft with larger antennas. but that's to be expected.

I've had little problem using it effectively out to 50 miles which is enough for planning. Even very large returns can be identified farther, but ground clutter due to tilt and downward slope of the signal requires understanding.

Well we all know that it will always be pilot error, but I wouldnt go on the flightaware picture alone. I have been using flightaware for years, and to be honest, the flight could have been going for hours, yet obviously the radar snapshot overlaid has to have been a single loop on the radar, the question is when? Especially when these cells can move at a very good pace, and we as pilots are trying to guestimate an aproximate 20 mile bearth. This is not an exact science for sure.:rolleyes:

if that is how you are using the radar you are using it incorrectly. at fl300 the radar should almost always be in the negative tilt. the crj radar is actually pretty good, you just have to know how to use it.

the correct way to use the radar on the crj 200 is as follows.

choose a distance you want to use. the 80-160 is not very effective but
still can be used to see larger items further away.

the best distances are the 20-40 or the 40-80.

the way to use the radar is set the distance you want to look at. then tilt the radar down till you begin to paint ground and you can see a fairly solid green arc at the furthest distance on your screen. once you have established a good ground paint arc then you can begin to watch for weather. the ground arc should stay at the same distance at all times unless you adjust the tilt again. ANYTHING that comes out of the ground arc you have been painting and comes closer to the plane is an area of weather and thunderstorms. you also at the higher altitudes want to point the tilt down a little more than normal. the crj doesn't pic up frozen precip so at the higher altitudes it wont paint storms unless you are pointing down below the freezing level.

so in review.

Point radar so that you get a good solid arc of ground clutter at the furthest distance for the range you have chosen. the ground clutter should stay the exact same distance from you.

If something moves closer to you out of the ground clutter it is an area of weather and should be avoided.

What about the children on the ground that you're blasting with radar?

Won't someone please think of the children :)

FYI, I heard the FA from that flight talking about it on the employee bus the other day. She said it wasn't nearly as bad as the media made it sound. Absolutely no injuries, and she said that one lady even had a cup of coffee in her hand... and she didn't spill a drop. (might I add that most FAs would probably over exaggerate things :))

I like to poke fun at Flagship as much as anybody else, but you have to consider the source.

I agree with airsupport. You definitely need to tilt down at cruise altitudes. Just always tilt so as to paint a little bit of ground and you'll be fine. Paint too much ground or too little ground and you won't see the cells very well. It only gets difficult when aiming at water, which won't paint, and mountains or major cities, which paint too much. In those cases just use the regular tilts that you would ordinarily use and just realize the ground paint won't look quite right temporarily.

Another thing to remember on the CRJ is that any gain other than normal disables the PAC alert. (Attenuation warning, for non-CRJ guys)

Well, if this "encounter" wasn't enough to spill any coffee from a passengers cup, then I have to wonder why they diverted ?

Overreaaction and/or hysteria on the part of an inexperienced flightcrew ?

I agree with your analysis that he is using it wrong but even your way of using it is incorrect. Well not incorrect, it will keep you alive but the return won't be accurate, it will overpaint weather. You will go around things you don't need to go around.

The goal of weather RADAR is to aim the beam somewhere between FL180 and 250 depending on who you listen to. David Gwinn says FL180. Archie Trammel says FL 250. Anyways. I use FL250 as a worst case "if I have to penetrate" level.

OK, how to aim it at that level?

Every 10 miles 1* of tilt changes the beam center by 1000' of your altitude.

What does that mean? If you want to aim it at FL250:

Q) You are at FL 250. Where should the tilt be?
A) 0* no matter what the range.

Q) If weather is 30 miles away and you are at 15,000, where should the tilt be?
A) Right around 3.2*. That will give you an accurate return on that weather.

Q) If you are on the ground departing on the 10-20 mile scale, where should the tilt be?
A) Anywhere from 10*-15*

The reason people think the RJ's RADAR "sucks" is because they don't know how to use it. We followed company the other day, 2000' below them. They didn't know how to use the RADAR and actually asked for a round about way around the weather in front of them that would've put them in a worse position because they were over painting a level 2 storm.

Landing in PHL the other day, ATC says "you'll go thru a level 3/4 return but the rides have been smooth, it's over the OM".

OK if this was really a level 3/4 return WE SHOULD NOT BE GOING THRU IT! It was a level 2 return.

For those who care the level 3 returns (red) start at 40 decibels. So compare your favorite online RADAR source with the 40 dbz returns and you can correlate what you are seeing out the window with what is being returned by ground based RADAR. The "red" on the NOAA/NWS site (NOAA's National Weather Service) actually is a higher level red than you will see in the cockpit.

Not sure about other RJ's but the limit on the CRJ-200 RADAR dish is around 45 miles or so to depict an accurate VIP level at altitude. This is due to the pickup of ground clutter, which can clutter up the display.

For bonus points what's the quickest way to determine if you are painting a city vs. a cell in the distance?

yes you dont want to over paint either. i guess i could explain a little more. once you start to paint a cell and you see it leaving the ground clutter and moving towards the plane then you can adjust the tilt up and see exactly how high it is. but then again if i am flying into memphis and all i see are a bunch of magenta blobs i will leave the radar where it is at and fly around them. i am really not interested in seeing which ones i dont need to go around. and we have had a lot of magenta blobs lately down here.

and for your bonus question i am going to say go to the mfd menu, select airports, and then if there is an airport where you are painting red then its probably ground clutter or a city.

I disagree precip held in the cloud by updrafts will still paint even if it is not falling.

Any storm that is worth going around will paint red at the FL250 level regardless if it is raining below it or not.

Yes you are 100% right. But sometimes you have to make a choice. You need to know what you can go through. Case in point, the "level 3/4 storm" over the OM in PHL. If someone won't go through a level 3/4 at altitude why would they go through it at 2000' AGL?

Yes that works, but easiest way is cities don't attenuate. With your way there might still be a cell on top of the airport/vor :eek:!

Business & Commercial Aviation - "Using Weather Radar to Counter FL Cells"

I consider myself a reasonably smart guy, but I've never understood the Trammel method of doing mental mathematics to use a radar while you're busy flying an airplane.

The guy who taught me how to use airborne radar and had a Ph.D in synoptic meteorology did understand it though...but didn't use that method while flying.

Radar usage is mostly technique, and there is no "wrong" way to use it as long as you're avoiding the worst of the weather.

It takes a split second to do the math. It's very easy once you know how to do it. I'm curious what method your mentor used, more so because I like to expand my knowledge on the subject, not because I am calling you out. Feel free to PM if you want.

Of course not, you are 100% correct. The issue comes up when you are down in the thick of it shooting approaches. If you are overpainting the cell you might divert for no reason, costing hundreds or thousands in fuel costs alone. It's important to understand the science behind it IMO.

Or in the majority of cases people assume the RADAR "sucks" and go through the storm cell. One day they'll do that on a true storm and get the crap kicked out of them (and that is if they are lucky). The boy who cried wolf comes to mind.

You guys sure that about Flightware history . My son was going into BNA a few days ago and complained about a lot of turbulence and lighting in a TRW. The A/C then diverted into BHM...i check the flight out using Flightware it it looks like somebody drove him through a line...nice

The radar on Flightaware does not accurately represent the actual weather an airplane works its way through along a flight.

There have been more times than I can count when, after landing, it shows me having gone head-long through a long line of weather when I was 40 miles in front and paralleling it.

I used to fly for PEANUCKLE before I grew up and got a real job. I heard this about a month ago on the radios..

Center: "Flagship slow to 250"

Flagship: "Ah, center stand-by, we have to get the books out for that one"

Center: "Flagship, are you saying you cannot fly 250?"

Flagship: "Sir, we have to see if we can fly that slow in the books!"


No kidding!
Way to sound professional Flagship, by the way, what is your recommended holding speed above 15000ft IAW the FOM, 225 knots? Also you could use Ref + 40 to figure out slowest speed, keeping within the stall margins...something like that?

dont believe it. but i am glad to see you have moved on to your greener pastures. congratulations to both of us.

no internet tough guy.....per FOM/cfm you can only fly in cruise .70 or LRC, whichever is less.

FWIW, I was referring to the CRJ. Never flown an ERJ/EMB (other than the Brakillya, which had an awesome radar).

Thank you professor! In my 8000 hours (3000 in a CRJ) I think I have a good grasp of how to use radar! I paint ground at 80 miles and +2. if you tilt it above that, you still see nothing.

If you point the radar to -2 at FL300 all you see is the ground more than 20 miles out. That's as useless as your advice. Let me know when you get typed on the plane.

That's asinine. We fly our CRJs at .65 all the time in accordance with our ECON SPEED (ACARS fuel saving program). It isn't going to fall out of the sky below .70!!!

I believe it. Since Flagship moved into ATL, I've heard some stuff on the radio that blew me away. And I've actually heard similar conversations to the above on the ERLIN arrival.

lol, vintage pennekamp. i am not the only one who thinks you dont know how to use the radar.. and i just might have a type in the crj and i now know i do have more hours in the plane than you. but since you know all i don't have to explain that to you. and its not professor, you can call me doctor.

It'll actually be around 40 miles (try it, I promise), and it's the way you're supposed to do it to get an accurate depiction of what you are painting. Because of the size of the RJ's RADAR 40-45 miles is the limit of it correctly picking up returns at altitude. Larger domes can go out 80 miles or so.

If you still don't believe me, look to an expert - David Gwinn. Gwinn's stuff is actually on Sporty's.

How Radar Works (Booklet and Audio CD) - Sporty's Pilot Shop

I've flown with 30+ year CA's who thought the RADAR was connected to the plane and when titled up +10 on departure was really tilted +25 because of the deck angle on the plane. Just because you've flown 8000 hours doesn't mean you don't know how to use the RADAR (don't worry, most don't).

Your way works OK for en route avoidance when you have a lot of space to go around cells. But it's not the most accurate way to do it.

uh, you do know what lrc is and how to use it right captain?

dont bother fosters. if you read his posts in other threads this captain cant be taught a thing.

That's too bad. I sincerely hope he doesn't end up injuring or killing people because of his hardheadedness.

in my 7000 crj hours I am going to say Airsupport is right. And yes I am typed in the AC.........and every radar i have ever used, the way Air describes it is the way I was taught. Being at FL300 and having the tilt at +2 at 80 miles, you're only gonna be painting a cell if it is really tall and right in front of you.

You mean like the ASA conversation last week that went something like this.....
"clearance ASA 5000 IFR ATL"
ATC..."clearance on request"
ASA..."yes sir, I just requested it. IFR ATL."
etc, you can see where this is going. Theres some at every airline John, even yours...

Yeah... 80 miles. The max range of the radar (duh).

Waaaaah! Waaaaah! JP was mean to me, waaaah!

So tell us, Doctor, you "may" be typed? Are you or not? Another right seat skipper, who challenges his captain on every thing, and thinks he knows it all, bitter he's not the Captain. Glad I don't have to fly with you. You're a regular Archie Trammel with the radar. Oh the skills! Then taking comments on an anonymous message board as if I insulted your mother. You must be a pure joy to spend 4 days with.

I won't be able to reply because this post will surely get me banned, but seriously, dude, get a life. See ya.

???
duh? by the way I put your 80 mile range in my post before you replied. But that shouldnt make a difference duh

Ha Ha. Yes, we have some of them, but not as many as some airlines. When we were hiring 500 Riddle Wonders, you heard a lot more of that, but since we haven't hired in about 1.5 years, most of them have been "educated" by now.