Originally published June 1993
In numerous publications, the FAA and other organizations encourage pilots to visit an FAA Air Traffic Control (ATC) facility. Project Police officers Mike Pelletier and Russ Erb decided to take on this dangerous infiltration assignment for the good of EAA Chapter 1000 and pilots everywhere.
The mission started by taking advantage of an underground contact within LA Center (ZLA). No, we didn't talk to the plumber. Steve McDougall, who sings in the church choir with Mike and Russ, is a controller at ZLA and a private pilot, although he says he hasn't flown in about three years. He agreed to assist the Project Police on this assignment.
Prior to departing, Mike tried to call ZLA to confirm our appointment. However, the FAA's defenses were fairly formidable. Mike got lost in the sea of voice mail, pressing 1, pressing 2, pressing anything in an attempt to talk to an actual human, but getting nothing but Muzac. This endeavor (not the Space Shuttle) turned out to be fruitless. We did not conduct a follow up investigation to figure out what was the deal.
On the evening of 28 April 1993, our illustrious Project Police officers proceeded on their infiltration mission into LA Center. ZLA is easy to find; head east on Avenue P from "the" 14, and turn left as though going into Blackbird Airpark. But don't turn left again into Blackbird Airpark, turn right instead into LA Center. After signing in, we met our host inside the building. The first sight we were treated to (other than rooms of lockers and a quick pass through the room with the working controllers) was a full wall covered with a huge relief map of the area covered by ZLA. (It's a shame we can't get one of these--it's great for seeing where all of the mountains are while planning your trip. Of course, there is the minor problem that it is about 10 feet by 15 feet in size.) ZLA covers an area from 200 miles out to sea, up to just north of Porterville, all of R-2508 (Edwards MOAs), east to Needles, and south to Mexico. This is one of the largest areas covered by a single center, and has more special use airspace to deal with than most centers.
We next proceeded upstairs to the DYSIM lab, which is used for controller training. The training these guys go through is very extensive, taking up to two years after they complete their initial training in Oklahoma City. The first bizarre thing I noticed was that the radar screen depicted all of the VORs, intersections, and airports, but none of them were labeled. The new controller has to memorize each of these VORs, airports, intersections, victor airways, jet routes, and their associated MEAs and MOCAs. Try sitting down with your enroute IFR chart and memorize every detail on it in two weeks time. At least the various radio frequencies for anyone you might get handed off to are posted around the radar screen. Its a good thing the FAA doesn't move its controllers around the country every four years or so.
Much to our surprise, each position is normally operated by two people, not one. These are known as the R-side (for Radar) and the D-side (for Data). The R-side obviously is looking at the radar presentation. The D-side tracks airplane data with paper strips. These paper strips are used as a backup if the computer goes down. Each position is equipped with altitude filters, which allows the controller to select which altitude blocks he is looking at. The presentation to the controller is fully synthetic, with no raw radar returns shown. Each aircraft symbol is assigned a data block, which contains its call sign, altitude that it is cleared to, its current altitude, ground speed, computer identification number, and which sector is currently controlling it. The controller can also pull up the aircraft's VFR or IFR flight plan on a separate screen.
The computer will flash the entire data block if a possible separation conflict is possible. The controller then decides if a traffic call is necessary. For example, the computer may detect a possible conflict, but the controller might ignore it because he knows the two aircraft will level off at different altitudes and thus maintain separation. When the aircraft is approaching a sector boundary, the data block will flash which sector the aircraft is about to enter. In this case, no land line communication is required, since the receiving sector will see the aircraft entering his sector and pick up the handoff.
We had been left to believe that when asked to IDENT, some huge marking jumped out of the radar screen, grabbed the controller by the collar, and screamed "YO, DUDE. HERE I AM!!!" Then again, maybe at sometime in the past such a system did exist, but was removed to save wear and tear (and early retirements) on the controllers. Instead, an aircraft that was asked to IDENT for us showed three flashing parallel lines about 1/4 inch long at the aircraft's position. To us, these were not real obvious unless you were looking for it. Likewise, squawking 7700 does not set off the fire alarm bells throughout the facility. In the past there were some alarms, but these were removed many years ago. This, obviously, was not demonstrated to us. We were told that part of the data block displayed "EMER" if you squawked 7700. Likewise, squawking 7600 displays "NORDO," and 7500 displays "HJAK." The screen does show the last three beacon returns from your transponder, to show the controller a history of where you have been. This lets him know if you are flying straight or in a turn. Moving radar returns that are not specifically being tracked show up as "+" on the radar screen. The interesting result of this is that ZLA can track trucks on Highway 58.
We did notice an obvious bias toward airline traffic, which is not surprising, since this is most of what the center sees. The controllers can generally tell you where each aircraft is headed, not from any displays on the screen, but just from seeing them everyday and basically the same time each day. We got the impression that there was no real animosity toward VFR pilots. However, you can make your dealings with controllers much more enjoyable if you stick to proper procedures and consider their side of the operation too.
VFR aircraft will show up on the scope with a data block showing your squawk code. If you request flight following, they will assign you a squawk code and generate a paper strip for tracking you. They will only know what type of aircraft you are if you tell them. Flight following is primarily a service provided for the pilot's benefit. There is no real advantage for the controller. Remember, ATC will not issue you vectors as a VFR pilot unless you specifically request them. This is particularly important to remember if a controller issues you a traffic advisory, and despite diligent use of your Mark XX eyeballs, you are still "negative contact." If the controller's voice is getting higher as he calls out "TRAFFIC NOW 12 O'CLOCK AND ONE MILE," simply say "Request vectors for separation" and he will gladly vector you out of harm's way.
We asked the controllers if they had any pet peeves from dealing with VFR pilots. The one they mentioned was pilots with "diarrhea-of-the-mouth" on initial call-up. This was new to us, since both Mike and I had CFIs who told us on initial contact to tell them everything they would want to know. For example, "LA Center, Tomahawk two five six six bravo at five thousand five hundred feet on the Palmdale VOR zero eight one radial at thirtyone DME squawking 1200 headed from Rosamond to Palm Springs." While you were babbling all of that out, the controller was wishing you would shut up so he could make a traffic call to someone on another frequency, clear someone to a new altitude, and about five other things. They would prefer that you dial up the frequency, listen for a little while, then make your initial call with who you want to talk to and your call sign. For example, "LA Center, Tomahawk two five six six bravo." Then be patient. Just because you don't get an answer within five seconds does not mean he didn't hear you. Finally, remember that the words "Radar Contact" do not mean that you can stop looking out the window. ATC does not guarantee separation to VFR aircraft (except in certain cases).
As for the working environment at the center, it was much different than I expected. I expected a bunch of rigid robots staring at screens totally detached from the world. In reality, the environment was relatively laid back, with people not currently on duty joking and poking fun at each other. These were normal people like any of the rest of us. Of course, this was not during the busiest time of the day. There were a bunch of chairs here and there, which I am told are all filled during the busy parts of the day. On the scopes, the controllers were relaxed but professional, as you would expect them. Some creature comforts do exist, as some controllers were observed munching on popcorn while vectoring aircraft. Normally a controller would work no more than two hours on the scope, with about a 20 minute break. A controller will work any sector within a given area, and will go to whichever sector comes up next for a break when his name floats to the top of next to go in.
As for the future, Steve expects to be getting some new equipment in the next couple of years. The current radar scopes were installed in the 70's, and the radios are 40's technology. He does not see the role of the controller going away, even with the proposals of a display in the cockpit to show the pilot where the traffic is. He expects that the controller will still need to take command and direct the traffic, or else anarchy might break out when pilots have no idea where the other guys are headed. Rather than just sit back and observe traffic, the controller will need to remain proficient in controlling traffic in case the system goes down and his services are really needed. Additionally, the controller is able to interpret many more situations than the computers can. For instance, the current TCAS system has problems, such as declaring a traffic conflict for a climbing and a descending aircraft when both aircraft will be leveling off before a conflict arises.
If all of this has made you want to run down to ZLA and request a tour, you might want to wait a while. They are currently removing asbestos from the building, and aren't too exited about the risk of a visitor getting cancer. What does this say for the people who work there? You decide.
We did find that your tour will probably be better if you can arrange it to be a few on one. A large group would be able to see the facilities in general, but a couple of people can really get in and study the displays and ask lots of questions.
Project Police Case #ZLA1.01 closed.
Epilogue: Mike and I flew down to Calexico the following Sunday, and took advantage of flight following during the trip. Our visit to LA Center made a big difference in helping us to understand what was going on. For instance, when they asked us what type of aircraft we were and where we were going, we knew why they asked and what they were doing with the information. It helped make flying in the Not-So-Big-Sky with ATC a little less mysterious.
Contents of The Leading Edge and these web pages are the viewpoints of the authors. No claim is made and no liability is assumed, expressed or implied as to the technical accuracy or safety of the material presented. The viewpoints expressed are not necessarily those of Chapter 1000 or the Experimental Aircraft Association.
Revised -- 2 March 1997