ATCC Controllers' Read Binder...

NOTAMS, FAQs and other info for users of ATCC

March, 1997

#1: Upgrades

We continue to work on the voice upgrade for its scheduled availability by July. It will most likely require Windows 95, a CD-ROM player, and "the more memory the better" (16MB or 32MB should be just fine).

Some have inquired about voice recognition. The technology is there, although the available software packages require some customization to allow them to work with ATCC. That will certainly be on our list for future enhancements, though, so stay tuned...

#2: Unknown Aircraft Calling You for Lower

If an aircraft not in your sector suddenly asks for lower, it's quite likely it was one you worked a long time ago, and just forgot to switch to the next frequency. The pilots just kept going on their merry way, though of course in real life the next controller would have called you up on the intercom and told you to switch them over. Not with ATCC, though...if you're working LA 38 for example, and forget to handoff or switch an aircraft to sector 34, and that aircraft is going to Boston, you can expect a call about 5 hours later asking for lower.

The solution is to ask their position with SP, and click out the range to see if you can locate them. If there is no datablock, you can bring it up with <F5> and the callsign, such as <F5>USA253. If you locate the aircraft, have him contact the sector adjacent to yours that was on his route of flight. So if you're at LA38, and an aircraft reports 50 south of DEN and is looking for lower, have him contact sector 34, since that would have been the next sector after yours along his route.

If they still come back to you, or you have no idea what sector to give them to, either ignore them, or descend them to 2,000 feet. They'll switch over to their destination airport's tower frequency automatically once they get about 5 miles away.

#3: Sector Frequencies

Almost all the sim frequencies are the real-life frequencies. If you happen to live anywhere near the sim sectors, you can tune in your scanner to the sector and here the real stuff too. It's all line-of-sight, so you'll probably just hear the aircraft. But if you happen to be within 20 or 30 miles or so of the transmitting antenna, you may be able to hear the controller. And the transmitters are scattered around the nation, so you may be able to hear the controllers even if you're in a remote area.

Often some of the sectors will combine with others during late-night operations, or split into two during busy times. Sector 75, for example, often is split so "another" sector 75 covers FL350 and up, and the "real" 75 just takes FL330 or FL290 to FL240. This means most of the enroute aircraft (cruising at FL370 or FL410) are taken out of the picture, so the sector 75 controller can just concentrate on the ORD arrivals.

But for the most part, what's in the sim is very, very close to what is going on in the real centers.

#4: New Sectors

As stated in the previous newsletter, creating new sectors is a lot of work. Some users have received the documentation on how to create new sectors, though, so there may be some more available soon in the public domain. Xavius does have another sector mostly ready, and it should be posted here around the beginning of next month.

If you want to create your own realistic sector, call the FAA in the nearest big city and find out the number to the "regional office." Ask the regional office which Centers are in the region, and for their phone numbers. Call the Center and ask for the Training Department. Tell them you are interested in observing some of their busier sectors, and find out if you can get an informal tour. They are usually very friendly, and don't get many people calling in for tours, so they should respond positively. The training department also has all the sector maps and frequencies, and should let you observe the sectors you'd like.

#5: Unfair Ratings

Outstanding controllers who are fast, efficient, and run sectors without conflicts or delays tend to blend in with most other controllers, and never catch the eye of the roaming supervisors, who are busy with the ones on the verge of panic, who wait until the last second then swear loudly and scream out "turn 90 degrees left!!! EXPEDITE YOUR DESCENT!!! EXPEDITE!!!!" If these panicky types somehow emerge without a deal, they are then rewarded for their perceived "hard work." This phenomenon is the same in every organization, and the world of ATC is no different. You may be an outstanding GS-14 who has worked many hours of the busiest traffic at the most complex sectors, then one little oversight and suddenly the datablocks are blinking, and 10 big points (or more!) are knocked off your rating, while the panicky controllers who only do the easy sectors seem to get all the good ratings.

Don't worry about it--your success is your ability to efficiently work busy traffic in the worst sectors, and even if you have a deal, everybody will still know you are a good controller if you truly are. The supervisors are required to take action whenever there is a deal, so they are mandated to knock down your rating regardless of the circumstances. Just move on, and build it back up. Anyhow, a 75 rating from working 97 or 19 or 66 is more praiseworthy than earning an 85 rating from only working sector 82!

#6: "MSR" Callsign

You may get this one in NY sector 66, which was inadvertently left out of the documentation. It's "Egypt Air."

Remember, even though the callsigns are only 3 letters, and VORTACS are only 3 letters, you should be thinking (or even speaking) their full name, so as you type in "USA321, ..CRL" you should think "U.S. Air three-twenty-one, cleared direct Carleton", and not "U-S-A-321, cleared direct C-R-L."

If a controller or pilot in real-life doesn't know or remember the full name of a VORTAC, the other acceptable way is to pronounce it with the international phonetics, as in "Charlie Romeo Lima." You should memorize the alphabet:

Alpha, Bravo, Charlie, Delta, Echo, Fox(or Foxtrot), Gulf, Hotel, India, Juliet, Kilo, Lima, Mike, November, Oscar, Poppa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu.

For the numbers, everybody knows "niner" for 9 (because "nine" sounds like "five.") Officially you should also pronounce "three" as "tree" (because "three" for some reason can sound like "two" over the radio), and "five" as "fife" to further distinguish it from "nine." 0 is "zero," not "Oh," unless used in an airline callsign (like "five-oh-nine" for AAL509).

The layman may think, "three...two...whatever! Close enough!", but as you know there can be a BIG difference between flight level two THREE zero and flight level two TWO zero, which is the reason for "official" pronounciations.

#7: Sequencing in Strong Winds

You may have found that your sequencing sometimes just doesn't work right! Remember to take the upper winds into account...there's no direct way in the sim to determine the upper winds, which vary from session to session (but usually out of the west), but you can look at the difference in groundspeeds between similar aircraft. In NY sector 66, for example, the JFK arrivals from the southwest may all show in the 500 knot range (meaning about a 50 knot or so tailwind), and the trans-oceanic arrivals only 380 or 400 knots.

Maybe you measure two arrivals from their convergence point (CAMRN), and find the oceanic arrival is 20 miles away, and the one from the southwest is 30 miles away. If they had the same groundspeeds, you could just leave them alone and the oceanic arrival would roll out 10 miles in front of the other, and you wouldn't have to do a thing. But with strong winds, even if you slow down the southwest arrival to 250 knots, he may STILL catch up to the oceanic arrival!

Thus you may need to modify your normal techniques of sequencing, when you have strong winds that create a large difference in groundspeeds. You might try just aiming the oceanic arrivals toward KARRS, and once they get in the PREPI-DRIFT area you can make a final determination where they'll fit in, and once you turn them to CAMRN or CRI they'll pick up the same tailwind as the others and the speeds will begin to match. If they appear tied with the other aircraft, aim them further south (maybe turn 20 left) then turn them back to CAMRN or CRI shortly afterwards. That's just one method, though--do what works for you!

#8: Radar Outages and Non-Radar techniques

Considering the enormous complexity of the multiple radar sites with the thousands of radar echos and aircraft targets and 40 or so controller scopes (actually just dumb terminals) with each controller making multiple keypresses and changing datablocks and everything else, it's amazing the real-world system doesn't crash more often. As every Windows 3.1 user knows, it doesn't take very much to crash a system, and that's with just ONE user! System crashes, or burps in the radar data can and do happen, though, as you've probably discovered with the "Not Receiving Radar" or "Not Updating Display" messages. Backup or redundant systems usually kick in right away, and the outage is only momentary, but you may have also discovered in the sim that it may last for 5 minutes or more. And 5 minutes means about 35 miles of movement with the big jets.

There are official "non-radar" techniques as briefly described in the User's Guide (pp. 86-87), but setting it up (figuring the intersection points, and the time estimates for each aircraft at each intersection point) would take too long. Your best bet is to control by "feeling," keeping your eyes on the scope (you'll still see the datablocks, but they won't move), and roughly knowing where aircraft should be based on how much time has elapsed. Then if you think two might be getting even somewhat close, verify their positions with SP and altitudes with SA, or pull up their strips to make sure they're assigned or are at different altitudes.

If the radar is out for an extended time, you should still be able to initiate handoffs as usual, and you should still switch them over when the datablock shows the handoff was taken.

When the radar is out, don't worry so much about getting the aircraft to the right altitudes or the right spacing. Just keep them apart until the radar comes back on! There's no "solution" to a radar outage problem, just use common sense and do what's best for the situation.

As a historical note, U.S. Enroute Centers were almost exclusively non-radar until the late 1960's, and even today there are areas where non-radar procedures are used routinely, mostly in remote, lightly-travelled areas where mainting a radar site is too expensive. Non-radar techniques are also similar to old train-dispatching separation methods, since the concepts are similar.

For an example of a non-radar sector, if sector 75 were exclusively non-radar, everybody would be put on airways, so discard the other routes (like DBQ..BRIBE or the MSP arrivals). Seven "bays" would be set up on the strip rack, each representing an intersection in the sector: DBQ, BRIBE, COTON, then the J16/J30, J105/J30, J105/J82, and J105/J90 intersections. When a strip is received on an inbound aircraft, the controller would make copies of the strip for each intersection it will travel through, and place those in the appropriate intersection bays, with calculated time estimates for crossing each intersection.

So, for example, if the controller received a strip on DAL888, flying east along J82-94, estimating DBQ at time 1130, he would put that in the DBQ bay, and make a copy for the COTON bay, and one for the J105/J82 bay, since those are the intersections it travels through. Because COTON is about 40 miles from DBQ, and say DAL888's speed on the strip is 450 knots (or about 7 miles per minute), the time estimate for COTON would be 1136. The next intersection, J105/J82 is about 15 miles further, or about 2 minutes, so the estimate there is 1138.

Non-radar controlling, then, involves looking at each bay and separating aircraft within that bay that cross within 10 minutes of each other at less-than-minimum altitudes. If DAL888 were at FL330, and another aircraft along J100 to DBQ then J82 to OBK was also at FL330 and estimating DBQ at 1138 (only 8 minutes apart from DAL888), those two would be in conflict. The controller might plan on descending DAL888 to FL290 to solve that conflict, but then he'd have to check the COTON bay and the J105/J82 bay to see if the new altitude would conflict with traffic there, too.

Non-radar controlling is very challenging, but basically impossible to do with the traffic volumes that exist today in the U.S. Many countries, though, which can't afford to build or maintain radar equipment, do still use these techniques for areas outside of their larger cities, though they may declare that separation is "attempted" and not "guaranteed," leaving the final responsibility to the pilots themselves.

Oceanic travel is also non-radar, though there are very few intersections and airways are generally one-way. By international agreement, New York Center currently handles trans-Atlantic separation, and Oakland Center (California) handles trans-Pacific.

#9: TRACON vs. Center Controlling

(Meaning working an Approach Control sector vs. working a Center sector, not Wesson's program TRACON vs Xavius' ATCC, which is obvious!)

There are those who will disagree, but in the honest, educated, practiced opinion of the author, Center controlling is much more difficult and challenging, in terms of mental calculations and problem-solving, than approach controlling. Approach Controlling, however (at a busy facility such as Chicago O'Hare) requires more alertness and quick responses, because starting an aircraft turning even 5 seconds late can disrupt everything.

Working at O'Hare approach, in fact, is about as "easy" as it gets, which is high praise for their efficiency at keeping things running smoothly. Chicago Center (e.g. sector 75!) does the dirty work of lining everybody up, nicely spaced 10 miles apart, then Chicago Approach gets 4 nice, neat lines of aircraft marching in single-file, all at the same speed. When an aircraft reaches a certain point, the controller turns him to a 90 heading. When he reaches another point, the controller turns him to a 360 heading. At the third point the controller turns him to a 300 heading and gives him the canned approach clearance and to contact the tower at a specific fix. All aircraft at O'Hare approach are either landing at or departing from O'Hare--there are no overflights (though ORD approach does work some in the outlying areas).

There are no intense mental calculations, no "what-if" scenarios, and generally no creative vectoring: everything is the same for every arriving aircraft. But timing is EVERYTHING, and if the aircraft isn't turned JUST at the right time, it'll miss the gap in the arrival line and will have to go around. There's no time to pick up a dropped pencil, or ask about ride reports, or to measure distances. Everything is NOW, and aircraft must be turned NOW or slowed down NOW or it'll all collapse.

Center controlling isn't as immediate, and proper control techniques are supposed to set things up (positive separation) so that nothing critical is imminent. But more thought and mental calculations are needed to make sure everybody gets where they need to go and at the altitude they want.

But, as you probably know, there are plenty of "imminent" and time critical situations in Center controlling, too! So be careful out there...


The Read Binder is updated at the beginning of the month. All information is for use with Xavius Software's Air Traffic Control CenterTM only, is the opinion of the author(s), and does not necessarily reflect the policies or practices of the U.S. Federal Aviation Administration or Federal Aviation Service. Send your questions or comments to and we may incorporate them in the next issue!