Say Again? #8:
Air Traffic Chaos

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It's that time of year again. The moist Gulf air and the Arctic air collide somewhere east of Phoenix and lines of thunderstorms rise into the flight levels. You've skirted more than a few of them over the years and know how it turned out for you; but how did it work out for the guys who opted for the other route. AVweb's Don Brown knows. He was watching the entire mess unfold on his CRT. If you want to hear from someone who's seen it all, don't miss the latest installment of

Let me make this clear right up front. I hate thunderstorms. I loathe them. I despise them. I'd rather work 10 years of wintertime IFR— icing, bad rides and all — than work one more season of thunderstorms in Atlanta Center. I'd rather take a beating and get it over with. After a day of working thunderstorms it feels like I've taken a beating anyway and it lasted eight hours.

Every morning when I get up, I download the national radar summary loop as I'm reading my email. I must be stupid. I'm just asking for it. If I see one little splotch of red headed toward my airspace my whole day starts off wrong. Evening shifts are the worst. If I'm working one, I can get myself real worked up hours before I even get to work. I can feel my blood pressure rising just writing this.

Pressure Rising Rapidly

Pressure FallingIt really cranks up as I'm walking in from the parking lot. You can see the usual suspects hanging around at the picnic tables. If you care to look closely you can see them twitching from 50 yards away. The smokers are sucking down cigarettes like it will actually make their life better and the non-smokers are looking at them with envy, wondering if they might be on to something. As you get closer you can see it in their eyes and you know it's coming ..."You don't want to go in there." "It's not too late, you can still turn around." "Here's my cell phone, you can still call in sick."

I ignore them and keep walking in the door. Down the hall, up the stairs and into the control room. You walk by the front desk, three different lines are ringing. Go by Flow Control, a dozen lines are ringing and all their pretty play toys are lit up like a Christmas tree. I don't even look to the right. That's the National Weather Service unit and no good news ever comes out of there. Around the corner and I'm in the Area.

And there it is. In living color. They've put the government version of a big-screen TV at the end of the cubicle that we're supposed to pretend is a control room. There are two different screens. One shows all the airplanes (color coded) going to airline hubs for which we're supposed to be running intrail. The other one runs a continuous radar loop of the weather just like you see on The Weather Channel. Red and yellow and pink and green ... purple and orange and blue. Just great. A rainbow from Hell.

Tic-Tac Anyone?

More twitching. The next time you're in a control room, take a look at the controller's legs. Take a look at all the pencil twirling. If you could harness all the energy expended in nervous tics you could light a small town. On the bad days you could power Las Vegas.

Pick your poison. Where do you want to start ? Low side, high side or ultra-high. It doesn't matter. It's like asking if you'd rather drink hemlock or strychnine. 

The first thing you need to know is that the weather display on a Center radar scope is downright pitiful. I guess I ought to use proper terminology. Radar picks up precipitation. It doesn't show "weather."

"H-H-H" That's heavy rain on a Center radar scope. No, I'm not kidding you.

" _______" That's moderate rain. So your typical thunderstorm looks like this:

___________________________
______________________________
_____________H-H-H-H-H-H_______
__________H-H-H-H-H-H-H________
________H-H-H-H-H-H-H_________
___________H-H-H-H__________
______________________

That also happens to be what ground clutter or an inversion layer can look like. You don't ever know. The weather portion of the radar display is so bad that many controllers refuse to use it. They usually formulate that policy after trying to vector someone around a thunderstorm and failing. They've vectored someone to a clear area and the pilot comes on the radio and says they are definitely NOT in the clear, they are getting their brains beat out. That cures most people.

Thunderheaded

Not me. I'm hard-headed. I've spent countless hours chit-chatting with pilots on the radio, comparing notes with what they see out the window and on their radar, with what I see on my scope. It's time-consuming and it's far from an exact science. It's also the key to making this sorry radar display usable.

You have to compare notes. I've seen days when the weather display was worse than useless. It was misleading. I've also seen days where it was just about perfect. I've never figured out why. The only way to know is to compare notes with a pilot. What he sees out the window is helpful. What he can see on the radar is even better. What three or four can see on their radar is best.

If our displays don't match up, it's going to be a long day. There are few things as frustrating as having a low-time pilot without any radar asking for some help around the storms and you can't give any. "Cessna 345 our radar isn't very reliable today. You're cleared to deviate as necessary, direct to GSO when able." Trust me, it feels as lame as it sounds.

Don't Follow Me I'm Lost

Being the resourceful government employees that we are, we have found ways of "making it work." Some people call them scouts or pathfinders. It's really nothing more than playing follow the leader. You find someone that does have radar and try to vector the ones without it right where the ones with radar went. You have to stay close though. Thunderstorms have this nasty habit of changing and moving on a constant basis.

Now that we've covered the fact that the weather radar doesn't always work, let's talk about when it does. The busiest chunk of airspace in the world is about five miles away from a thunderstorm next to an airline hub. Everybody wants to skirt right along the edge. Well, guess what? Everyone can't. Not if you want everyone to live.

I understand pilots wanting to deviate as little as possible. What I don't understand is controllers who let them. Okay controllers, all together now. What's our mantra? Safe, Orderly, Efficient. Okay then, let's step back and look at this situation while we have a chance.

Deviants

"Deviate south as necessary — cleared direct XYZ when able." It doesn't sound like much "control" is being used does it? Don't get me wrong. It's a useful clearance. It's one I use a lot. It's not the only trick that we have available to us though.

Some airplanes have to be close to a thunderstorm. Mostly the ones that are landing or taking off at airports that are near the thunderstorms. Others don't have to be close though. They may want to be close, but they don't have to be. So why do we let them get that close? Because somebody, somewhere keeps emphasizing the "Efficient" part of ATC instead of the "Safe and Orderly" part.

Try this the next time you're working with thunderstorms. Ask yourself if a particular airplane really needs to get into the fur ball. If not, route them out of the problem. Don't make the guy that is working 10 airplanes that are deviating decide. He's got enough to do. Put them on a route that is at least 30 miles away from the thunderstorm — not a random route either — a good old fix-to-fix route that doesn't ride the border and/or cut a bunch of sector corners. The idea is to cut down on the coordination, not create more. Put the route in the computer so the next controller down the line will be prepared for it. Try it one time. You'll like it.

The Complaint Department Is Closed

Now for you pilots out there, don't complain about it. Seeing as I know you're going to anyway, don't complain about it more than once. It's safer. It's more orderly. That means in the long run it will be more efficient — for you and for everyone else involved. Take solace in the fact that, if we don't do something about it, you'll be sitting on the ground waiting for a clearance because we'll shut the system down if it gets out of hand.

I haven't said anything about it since my first article ("A Wing and a Prayer") so I'm going to say it again. Frequency congestion is the number-one bottleneck in the Center. Look at all that I have written above. Just imagine how much frequency time it takes to accomplish everything extra we have to do during thunderstorm season. You have the same problem. You need to say more because you need more information and you'll probably need to deviate at some point in time. The result is lots of frequency congestion.

Bad Habits And Bad Timing

In writing these articles I've been pleasantly surprised at how receptive the readers have been to constructive criticism. I really appreciate it. So let me abuse your kindness. For those of you who didn't "get it" when I said "talk less" in "A Wing and a Prayer," let me be blunt — SHUT UP. Sorry. I don't mean to be rude. I do want to get your attention though.

Thunderstorms are dangerous. Trying to control a dozen airplanes that are deviating around them is a lot more dangerous than working a dozen airplanes sailing through smooth skies in straight lines. A report of "light chop" doesn't even rate on a day like this. "Prompting" controllers that you'd like to get to your requested altitude goes from being an annoying practice to a dangerous distraction. If it doesn't involve the safety of your flight, it probably doesn't belong on the air. We've got our hands full. So do some of the pilots on the frequency. If you don't, stay off the radio.

I really hope the above paragraphs don't come out wrong. I'm finding that the lack of understanding at all levels between pilots and controllers isn't being addressed. The best programs that we had (Familiarization trips for controllers and Operation Raincheck for pilots) have been severely curtailed or eliminated since September 11 due to security concerns. Somebody in Washington with the "big picture" needs to get on the ball and get those programs going again, or find suitable substitutes.

Groundhog Day

Advancing T-storm LineI wish a had a nickel for every time I've seen this scenario. I'd retire — before I see it again. It's Spring and Mother Nature decides to play her usual tricks. Warm Gulf air comes up from the coast and cold air comes sweeping down the plains. They meet around Oklahoma and the fireworks start. A line of thunderstorms cranks up and cut's the country in half, diagonally, from the southwest all the way to the northeast.

It's your basic, ordinary, everyday thunderstorm pattern. So why do we act like it's the first time we've ever dealt with it? We know that it's going to get into Atlanta Center's airspace on the northwest corner, just west of TYS (Knoxville, Tenn.), and droop south as it moves east. A couple of hours later it will wipe out the RMG (Rome, Ga.) arrival on the northwest side of ATL and very shortly thereafter wipe out the LGC (LaGrange, Ga.) arrival on the southwest side — and the shuffle starts. All the airplanes that were to use those arrivals will try to find a way east, to get on the MACEY arrival from the northeast or the SINCA arrival from the southeast.

Tick-Tock

I know it sounds complicated but it's not. Pull out the chart and take a look at it. Pull out your ruler and lay it out on about a 45-degree angle from the southwest to the northeast. Pretend that's a line of thunderstorms. Start the clock and start dragging the ruler across the chart to the east-southeast. Try to imagine where the airplanes will have to go to get around the ruler/thunderstorm line.

If you've got it laid out properly, the middle of your ruler ought to pass right over RMG. Let's stop the clock and take a look at what we have. If you're inbound to ATL (or its satellites) from the northwest, to get around the line you'll have to take a sharp turn to the southwest or a sharp turn to the northeast. Let's go to the northeast. Turn the clock back on.

You turn to the northeast and run parallel to the line of storms. About 40 miles west of VXV (Volunteer/Knoxville, Tenn.) you get around the end of the ruler/thunderstorm. "Atlanta Center, we're around the storm now how about direct Atlanta?" You're kidding me right? Every airplane in the world is hugging the east side of that line including all the Atlanta departures scheduled to come out the north departure gate and half that were scheduled to come out the west departure gate that is now blocked. You're cleared direct VXV (Volunteer, Tenn.) and the MACEY2 to ATL.

You get over VXV, turn south to MACEY and then turn southwest toward the airport at ATL. You're thinking you're home free aren't you? Look at the ruler. You have been moving the ruler/thunderstorm haven't you? It takes time to deviate and those thunderstorms don't stop moving. They're now sitting right over the top of the Atlanta airport and no one is landing, period.

When To Hold 'em

So we stack them up over MACEY. Keep moving that ruler. It doesn't take long to figure out where those thunderstorms are heading does it? Yep, right toward MACEY. Now, if you ever want to see a three-ring goat rope, just let a thunderstorm catch us with a holding stack full of airplanes.

Makes you wish you'd landed back before Rome or held and just waited it out doesn't it? There's a hint in there folks. Look at your ruler/thunderstorm again. What's the first arrival fix that is going to open up? That's right, Rome. Simple huh? Makes you wonder why more people don't do it, doesn't it? I know the airlines aren't going to take that advice, but you can.

I actually talked a commuter pilot into it one day. Somehow I had avoided all the craziness and only had two or three airplanes in the sector. The sector above me forced a commuter down into my sector to make more room in the holding pattern on the northwest side of CLT. (This game is played at every hub-and-spoke airport. The rules are the same.) Flow Control wanted me to route the aircraft around the thunderstorm to the southwest arrival. I told the pilot that he could deviate all over North Carolina, get through the line somehow, get in the path of the line of thunderstorms, be number last at that arrival fix just in time for the airport to close....or he could sit in a holding pattern on the northwest side of the airport for 30 to 45 minutes and be number one when the thunderstorm passed over the airport and it opened back up. He choose to stay put. He was the first airplane to go in when Approach started taking airplanes again.

When To Fold 'em

A variation on that theme that is perhaps a little more useful to many of AvWeb's readers is the situation when you're en route from the other side of the line of thunderstorms. From the southeast side heading northwest. You're looking for a hole in the line. You're asking ATC if they know where a hole is and it's just not working out. The solution is right below you. Land. Get up as close as your comfort level allows you, pick out an airport and land.

I don't know why that idea doesn't occur to more pilots. The times that I've been bold enough to suggest it to a pilot on the radio has always been met with, "That sounds like a good idea." Controllers are reluctant to go so far as to suggest you should land. We figure that's your decision to make. But let's look at the options.

Option one. You can sweat bullets for 30-45 minutes trying to find a hole in the line. You can bounce up and down, turn this way and that and make your passengers nervous. You're liable to wind up a hundred miles off course and wondering which will give out first, your fuel or your bladder.

Option two. You can pick an airport close to the line and land. You can gas up the plane and maybe meet some new friends. You and your passengers can grab a cup of coffee, wander out on the catwalk and watch the storm blow all the airplanes around at their tiedowns. You go back inside, use the restroom, pay for your fuel and file a new flight plan. In 30-45 minutes you and your passengers zoom off into a clear blue sky that looks like it has just been washed clean by a spring shower. You're refreshed and feeling good. Your passengers think you're one smart pilot and, looking back on it, you even feel pretty smart.

Option three. We're not going to talk about option three. You'll pick option two before you suffer option three — right?

Breaking Even

There's too many things to cover about thunderstorms, so let me lay out a few things for you to think about. A line of thunderstorms generally moves eastward. If you get on the east side, the thunderstorms will be chasing you. If your flight plan is going to cross a line of thunderstorms, then you don't really have a "plan." Don't be one of the guys that doesn't have a plan and sticks to it. When controllers clear pilots to deviate, we usually have a pretty good idea how far you're going to turn. Most turns are under 30 degrees. If you're that one guy in 50 who's going to turn 90 degrees off course you might want to say something — something that gets the controller's attention. Telling your co-pilot to hold your beer and to "watch this" doesn't count.

I'd love to share some war stories. The Mooney that got turned upside down comes to mind. So does the King Air that was bouncing up and down so much that the computer couldn't decipher the Mode C — or the Bonanza pilot who, when told that a Boeing 737 was reversing course at twelve o'clock and twenty miles because he was getting beat up so bad, replied, "Oh we'll keep going and have a look at it." I'd really love to tell you about my personal favorite, the Sabreliner that shot the visual approach into a Level Five thunderstorm.

I've got a career full of war stories and they just won't fit into one article. They all come down to the same thing though. Thunderstorms are dangerous. You'll survive most of your encounters with them. But if you roll the dice often enough, they will come up snake eyes. Every year someone becomes just another statistic. Don't let it be you.

Have a safe flight!


Don Brown
Facility Safety Representative
National Air Traffic Controllers Association
Atlanta ARTCC