Controllers' Handbook
last updated Tuesday, June 1st, 2010 @ 14:40 UTC


This manual assumes you have already read through the Pilots' Handbook, and the Communications Handbook. Much of what is listed there should give you a solid head-start on what you need to do, and how you need to do it, as a controller for TransGear Airways.

If you are not yet a TGA-approved controller, please understand that while I allow a great deal of leniency for new pilot participants and the learning curve that comes with communicating via voice for potentially the first time, none of this applies to my controller staff. I have extremely high standards and expectations for good procedural adherence (to the extent that it's laid out and watered down for these events anyway), good phraseology and terminology (as outlined in the guidelines below), good separation and intercepts, and a confident and professional "presence" on the channel. The reason for this is that the controller staff is critical to maintaining a good flow to the event. Pilots are going to fly their planes more-or-less the same, regardless of how well or poorly they know how to communicate. But a good versus a poorly-skilled ATC can really impact the quality of the event.

Equipment / Software

As far as the physical tools involved: whatever your preferred setup may be is fine by me. Whether you rely on the Multiplayer Map, one of the ATC-sets available on the downloads page or in the CVS (or now the "git") repository, the version with multi-lingual chat support created by Jorg Emmerich, the TGA-optimized version created by me (available for download here), or something else entirely, it doesn't matter to me. Just make sure you're able to see aircraft within your intended control area, and can monitor the text chat while working with most participants via FGCom. Whatever combination of tools accomplishes this most comfortably for you is perfectly acceptable.


At present, each "hub" airport is staffed with a two-person Air Traffic Control crew; one handling Approach and Departure, and one handling Tower and Ground. At this time there is no need to implement Clearance Delivery, ARTCC ("Center"), or multiple Approach/Departure sectors. ATIS services are also ignored for the current scope of this event. See "Future Expansion" below for some thoughts on how this staffing arrangement may evolve over time.


This is probably the one area where I am least willing to bend. I request that my controller staff please use the callsigns listed below, exactly, without exception.

Callsigns in FlightGear's multiplayer system are truncated at seven characters. I ask that the first two of these represent your position as either "Ap" (Approach/Departure), or "Tw" (Tower/Ground). The remaining five places should represent the frequency in use -- if there is only one digit after the decimal, a hyphen should replace/represent the decimal; if there are two places, no dash or decimal may be used as the callsign will need all five remaining characters to represent the frequency.

As a result, the callsigns to be used in the current format are as follows:

To keep the initial contact frequencies consistent from event to event -- if there is one controller staffing an airport, use the "Tw" prefix but operate on the Approach/Departure frequency!

The purpose for all of this strictness is to provide a billboard over the Multiplayer Map to non-TGA pilots that there is an air traffic controller at this location, and give some hint of what services they are providing and how they may be contacted. Surely, many such pilots will not be FGCom equipped, but those that are will hopefully have an instant recognition of the fact that the controller is "broadcasting their frequency" and thus may jump at the chance to participate with a live-voice air traffic controller -- and if they come and see what's going on, perhaps they'll become interested in participating in the events down the road. In short, these callsigns are intended not only as informational tools, but recruiting tools.

Terminology / Phraseology

The procedure guidelines set forth in the "responsibilities" sections below lay out pretty explicity what I hope would be used as standard phrasing. They are probably not one-hundred-percent real-world rigorous, but are certainly based in reality as closely as possible. While I would stop short of mandating that those lines must be rehearsed and recited verbatim, as I understand there may be an unusual case that may spring up here or there requiring some creativity, I would certainly like to know if there's a compelling and/or recurring reason to stray too far from what's presented there. If any of these resources are found to need modification or amendment, I'm happy to do so -- contact me on the FlightGear Forums via PM, or simply e-mail me if you would like to discuss any part of the phrase guide.

Responsibilities -- Approach/Departure

Minimum Separation Standards. In the real world, minimum separation standards vary by airspace type, as well as per aircraft based on their navigation equipment, crew certification levels, and size considerations such as wake turbulence, etcetera. For our purposes and to keep things a little simpler, uniform separation standards of 3nm lateral or 1,000ft vertical will be sufficient. Notice the word "or" -- meaning, if the altitude of two passing aircraft differs by 1,000 feet or more, they may pass within 3 miles of one another. Aircraft within 1,000 feet of the same altitude should be kept at least three miles apart.

For your purposes, arriving aircraft will be loosely grouped into three categories:

  1. those arriving on a STAR which leads directly into the active arrival runway IAP,
  2. those arriving on a STAR which requires Approach control intervention after a given waypoint to smoothly transition them into the IAP,
  3. those arriving who are not following a STAR (regardless of how they are managing their navigation).

You will have to consult the STAR chart they are following to know whether it falls into situation (1) or (2) above.

To make your life easier, it's suggested to have those that are arriving under condition (1) report crossing the waypoint immediately before the initial approach fix. Then you can pretty much let them "do their thing" (though you might need to monitor and manage their speed) -- when they report back to you, it'll be time to clear them for their approach and hand them off to Tower. Similarly, those arriving under situation (2) above could be asked to report the second-to-last waypoint in their procedure, to give you a heads-up that they will soon need to slow down and begin receiving vectors to get lined up for their approach. Of course, in either of the above two cases, you could always change your mind depending on other traffic later, and have them break out of their STAR procedure earlier if it becomes necessary.

Note that all pilots, even those arriving via non-procedural means, are initially offered an ILS as opposed to a visual approach. This is more about the pilots' skill and knowledge level than following any real-world consistency. Pilots in any of the three categories above may request a visual; there's really no difference in how they should be handled until localizer intercept, as discussed below.

Localizer Intercepts. Once the arriving aircraft are at approximately 2000 feet AGL and 170 knots (with exceptions to altitude based on radically unusual IAPs, and to speeds based on aircraft perforamnce characteristics), localizer intercepts should be set up such that the difference between the aircraft's heading and the localizer heading is no more than 60 degrees; the shallower the turn, the better, where an angle of 30-45 degrees is preferred. For example, if the approach heading is 230, the aircraft should be routed across it at a heading of no less than 170 and no more than 290; but a range of 200-260 is better, as pilots making 60-degree turns onto the localizer will tend to overshoot. This intercept should be made absolutely no closer in than 5 miles from the touchdown zone but a distance of 10-15 miles is preferred.

ILS versus Visual Approaches. Aircraft on ILS approaches, once they are on an intercept heading, should be cleared for ILS approach and immediately handed off to the Tower. There is no need to vector them directly toward the airfield -- the localizer will handle that. On the other hand, pilots on a visual should be vectored as closely to "right down the beam" as you can get them, and should be asked to "report visual with the runway." Once they have the runway in sight, then they may be cleared for their visual approach and handed off to the Tower.

Missed Approaches. If an aircraft on your channel reports a missed approach, they may be following the published procedure, or they may elect to follow the "TGA missed approach" version which is to fly the runway heading and climb to 5,000 AGL. In either case, you are free to immediately issue them a new vector and altitude (which overrides/supersedes either of the aforementioned) to quickly sequence them for another attempt. Those reporting missed approaches on the Tower channel may be given a vector and altitude assignment by the Tower controller, in the interest of spacing with other traffic, before being handed back to you -- hopefully your "partner" will notify you via MP Chat what they have instructed the aircraft to do.

The general process for all arriving aircraft is as follows (modify as necessary for special circumstances):

At this step... ... with this approximate range to destination... ... for this type of arrival... ... issue this instruction.
Aircraft Initial Check-In 80nm all "TransGear {flt#}, {facility} Approach, radar contact, altimeter {altimeter setting}, expect ILS approach runway {rwy#}."
At any point you feel it necessary for spacing, or to progress them towards the localizer intercept 80-10nm all except (1) above
(at controller's discretion)
"TransGear {flt#}, turn [left | right] heading {hdg}."
"TransGear {flt#}, descend and maintain {altitude}."
(NOTE: both a new heading and new altitude may be combined into a single instruction if necessary.)
Aircraft is descending below 10,000 feet 40-60nm all "TransGear {flt#}, reduce speed 2-5-0 knots."
Aircraft is approaching within 30nm 25-30nm all "TransGear {flt#}, reduce speed 2-0-0 knots."
Aircraft is approaching localizer intercept 15-20nm all "TransGear {flt#}, reduce speed 1-7-0 knots."
Aircraft is on localizer intercept heading 10-15nm ILS approaches "TransGear {flt#}, maintain heading until intercepting localizer, clear for ILS approach runway {rwy#}."
Aircraft is approximately following localizer 8-15nm visual approaches "TransGear {flt#}, range {nm} miles, report visual contact with the runway."
Aircraft has reported runway in sight 5-8nm visual approaches "TransGear {flt#}, clear for visual approach runway {rwy#}."
Aircraft has been cleared for ILS or visual approach 5-15nm all "TransGear {flt#}, contact {facility} Tower on {freq}."
Notify Tower controller of handoff and assigned runway via MP Chat.

As each aircraft clears the runway and establishes positive climb, Tower should hand them off to you. They should advise you via MP Chat regarding any altitude and/or heading assignments they were given.

Departing aircraft, when they check in with you, are supposed to advise you whether they are following a SID or are expecting vectors; if the latter, they should advise the general direction of their destination. If not, you will have to ask them. Unfortunately this often becomes a longer question-and-answer session than you probably have time for -- as pilots get used to our procedures hopefully they will remember this for future reference.

Fortunately, once you've established their intentions, you shouldn't need to worry too much about them. Those that are following a SID should only need to be told to proceed direct to their first waypoint (it's nice to refer to that point by name, so you should have the various SID charts handy) and then "resume own navigation"; the ones who are just looking for vectors in a general direction might need to be given a turn or two for spacing before telling them the same. Once they're safely out of the way of each other and any incoming traffic, you can let them go until they get near the end of radio range and then clear them from your channel.

At this step... ... with this approximate range from departure... ... on this type of departure... ... issue this instruction.
Initial contact 1-2nm SID "TransGear {flt#}, {facility} Departure, radar contact, proceed direct {SID entry waypoint}."
Initial contact 1-2nm vectored "TransGear {flt#}, {facility} Departure, radar contact, turn [left | right] heading {hdg}, climb and maintian {altitude}."
At any point you feel it necessary for spacing, or to progress them toward their destination and cruise altitude 2-70nm all "TransGear {flt#}, turn [left | right] heading {hdg}."
"TransGear {flt#}, climb and maintain {altitude}."
(NOTE: both a new heading and altitude may be combined into a single instruction if necessary.)
At any point you feel comfortable that an aircraft is out of the way of departing or arriving traffic 10-70nm all "TransGear {flt#}, resume own navigation."
As an aircraft is nearing the edge of radio/radar contact 70-75nm all "TransGear {flt#}, clearing my airspace, radar services terminated, frequency change approved."

Responsibilities -- Tower/Ground

The Tower/Ground controller is responsible for all aircraft movement in the immediate airport environment. Fortunately there aren't any assigned terminals or gates for TransGear aircraft, so interaction is generally minimal as pilots are free to taxi and park wherever suits them. So the main responsibility of this controller generally ends up being to sequence arriving and departing aircraft in a smooth, safe, and efficient manner. Arrivals should naturally be given precedence, since departures can easily stop and wait on the ground while arrivals obviously cannot.

Don't forget that all landing and takeoff clearances should be preceded by a wind report (heading followed by speed); and in all runway clearances the runway number should be verbalized followed by the type of clearance ("position and hold", "clear for takeoff", "clear to land"). Also note that the words "takeoff" and "land" are only used when issuing an explicit runway clearance for either -- at all other times on the channel, these acts should be referred to using forms of the words "arrive" and "depart".

Once an aircraft is handed to you from Approach, doing anything with them besides clearing them to land will probably significantly disrupt their day. The pilot should advise you on check-in which runway they are approaching; as a backup, the Approach controller should notify you via MP chat at the time of the handoff. Clear them to land as soon as they switch over unless there's an extremely compelling reason why you shouldn't. If there is a traffic conflict of some sort, however, you should feel free (as a last resort, of course) to order an arriving aircraft to perform a "go-around."

Missed Approaches/Go-Arounds. If an aircraft on your channel reports a missed approach, or if you should have to order a go-around for any reason -- the pilot may elect to follow either the published procedure or the "TGA missed approach" version which is to fly the runway heading and climb to 5,000 AGL. In either case, you are free to immediately issue them a new vector and altitude (which overrides/supersedes either of the aforementioned) if necessary to avoid traffic near the departure end of the runway, before handing them back to Approach; however, they should be handed back to Approach as promptly as possible. Additionally, please notify the Approach controller of the missed approach via MP Chat, including any altitude/heading assignments you may have issued.

At this step... ... issue this instruction.
An aircraft checks in on final approach "TransGear {flt#}, wind {heading} at {speed}, runway {rwy#}, cleared to land."
An aircraft has touched down and begun braking "TransGear {flt#}, make any available [left | right] turn off of the runway and taxi to the gate of your choice, remain on this frequency."
(NOTE: if they will be crossing any other runways enroute to the terminal, add "... hold short of runway {rwy#}." to that instruction, and then clear them across it once they arrive there.)

The Tower/Ground controller manages everything each aircraft does from just after preflight until they're off the runway and airborne. Of course, it is not now nor ever has it been Air Traffic Control's responsibility to manage anyone's flight schedule; the pilots should know that it's on them to check in with you as soon as they are ready to go, at or after their scheduled departure time.

At this step... ... issue this instruction.
An aircraft has requested startup and/or pushback "TransGear {flt#}, cleared to start up and push back, expect runway {rwy#} for departure, report when ready to taxi."
An aircraft has reported ready to taxi "TransGear {flt#}, taxi via {taxiway#(s)} to {rwy#} and hold short."
(NOTE: if there is a crossing runway before their departure runway, clear them only as far as that for now.)
An aircraft has arrived at a crossing runway (IF APPLICALE) "TransGear {flt#}, clear to cross {rwy#}, then continue on {taxiway#} to {rwy#} and hold short."
An aircraft is at the departure runway -- the arrival end will remain clear but there is traffic further down or on a crossing runway "TransGear {flt#}, runway {rwy#}, position and hold."
An aircraft is at or on its departure runway, and the way ahead is clear "TransGear {flt#}, [fly runway heading until {altitude} | {other instruction} | {none}], wind {heading} at {speed}, runway {rwy#}, clear for takeoff."
(NOTE: if the aircraft is departing via a SID, the instruction given to them just before the takeoff clearance should be consistent with that SID if possible. Otherwise, an assigned initial altitude is preferred but not mandatory.)
An aircraft has taken off and achieved approximately 1,000 feet of altitude above ground level "TransGear {flt#}, contact Departure on {freq}."
Notify Approach/Departure controller of handoff, assigned heading/altitude if given, and SID if known, via MP Chat.


(NOTE: the guidelines set forth in this section are new as of June 2010.)

Because TGA event controllers are hampered by the limitations of the FlightGear multiplayer environment, particularly that they do not have the ability to see and share information on pilots' flight plans, I recommend a simple coordination method between Approach/Departure and Tower/Ground to assist them in working together efficiently as a team.

Pre-Agreed Parameters. The Tower and Approach controllers should agree on one or more Arrival runways beforehand, at the time they are both getting logged on and set up, especially at Atlanta where there are five to choose from. In Indy, it may be simply where the two controllers agree on a direction for the main runway pair (5 or 23), and then use either side depending on the direction each arrival is coming from. Whatever the two controllers agree on is fine with me.

Multiplayer Chat Notices. When handing an aircraft off to your "partner," I ask that you type a Multiplayer Chat message to notify them that the aircraft is switching over and what they have been cleared to do. This will act as (1) a backup to the pilot giving their intentions in the initial check-in, which many (especially newer participants) will fail to do; and (2) a partial substitute for our current inability to submit, monitor, and share information about pilots' flight plans.

When handing an aircraft from Approach to Tower for an arrival, the Approach controller should notify the Tower what runway they have been cleared for. Because both of our present hub airports have several parallel runways it is not always possible for the Tower controller to determine visually which one an inbound aircraft is lining up for; a quick "heads-up" from Approach will help Tower decide if a departing aircraft can take their runway now or whether they should wait until after the arrival. The message doesn't have to be any longer than "Twr, TGA1260 coming 2 u, ILS 9L".

Similarly, when handing off an departing aircraft from Tower to Departure, Tower should pass along any post-takeoff instructions the aircraft was given prior to switching over. If they were cleared to 5000 feet, that's useful information for Departure to have. If Tower happens to know what direction or SID the aircraft plans to follow, even better. "Dep, TGA1260 coming 2 u, rwy hdg to 5000" is probably more than sufficient.

Secondary Frequency Monitoring. Finally, there's one "trick" some controllers may be able to use to make coordination easier, which is to run a second instance of FGCom as a "monitor" of their partner's frequency. (This may not be possible on all operating systems or with all sound card configurations.) The way to do it on Windows (and probably also Linux) is to start a command line in the active directory where FGCom lives, and run this command (for example, if you are working Atlanta Tower/Ground):

C:\Program Files\FlightGear\bin\FGComGUI> fgcom.exe -aKATL -f126.9 -i0 -o0.4

... and you should get the following response from the console window...

fgcom - a communication radio based on VoIP with IAX/Asterisk
(c)2007 by H. Wirtz
Version 1.2.2 build 226M (with FGComGui patch)
Using iaxclient library Version SVN UNKNOWN

Successfully parsed commandline options.
Reading list of airports...done.
Initializing IAX client as
Call 0 accepted
Call 0 answered

... if you do not see the "Call 0 accepted" and "... answered" messages, something is amiss.

This will run FGCom on the default server with Atlanta Hartsfield as the location monitoring 126.9 MHz (the Approach frequency) with an input volume of zero and an output volume of 40 percent (of course, you can adjust the output volume to suit your taste). If you're a good multitasker, you can hear which arrival runway Approach is having each aircraft expect as they initially check-in, and can hear the information again when the pilot is cleared for his approach to that runway. The chat message will then serve as a backup in case you are busy on your channel and fail to hear the handoff.

Future Expansion

Per suggestion by Peter (Farmboy) among others, currently I am considering implementing a Center controller stationed approximately midway between KIND and KATL to assist in maintaining an orderly flow of traffic during the "second phase" of the event when essentially all traffic is passing between these two locations. I have presently tabled that thought as I am hoping to focus first on new pilot recruitment to boost the number of participants back to the levels we enjoyed in the early part of 2010. At the levels of participation we have seen in late Spring and early Summer of this year, no Center controller seems necessary. I'm not fully convinced one would be required even at a full roster of 20 pilots, but I'd like to head in that direction first before I consider this matter any further.

At various times we've also discussed expanding the airport staff to include separate Tower and Ground controllers, but again, with traffic levels where they are now, I hesitate to see this as a priority.

Generally speaking I would much rather find ways to boost pilot participation well before giving serious thought to expand the Air Traffic Control facet of the events.

Should we find ourselves in need of additional pilot slots at some point, I'm hopeful that we can add some additional destination cities in the USA East region or start expanding into some longer-haul flights to the West; however, another suggestion was to simply "double-up" flights on already existing routes. Certainly a prefix of "2" rather than "1" (i.e. in the thousands place of the flight number) would easily designate a second flight on the same route, and the time could just be offset by fifteen minutes from the first departure to allow for some spacing and variance in the time slots available.


Above all else, I try to promote each TransGear event as a friendly, casual, fun learning environment. So regardless of any problems that may have appeared during any event, I would hope that any "Monday-morning-quarterbacking" that goes on in the forums remain positive in tone and constructive in nature. I'm not asking that negative issues not be discussed, but simply that we remember that the goal is a learning environment, and that any problems should be discussed and approached with an eye for what can be learned from them.

If there are problems with individual pilots that might not be useful to discuss in a public forum, I recommend that those issues remain in PM, or be brought to my attention privately so that I may determine how best to handle them. Certainly I hope that we wouldn't even have to worry about considering sanctions against any participants, but if we even enter into that arena I would hope that those sorts of decisions would be left to me.

One final note -- I know that I tend to be set in my ways about a great many things. But, I do my best to be receptive to feedback regarding any of my roles here, whether to do with my participation as a pilot or controller, or the way I organize, promote, and chair the events. I always invite any and all participants or other interested parties to e-mail me, and I do my best to respond to all questions and concerns, and consider all ideas thoroughly before deciding whether to implement them or pass on them.

So in conclusion, please contact me anytime you have questions, concerns, ideas, or any other relevant thoughts. I thank you for your continued interest in TransGear Airways events.