STRIPS

SCHEDULE

DEPARTURES

ARRIVALS

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METAR

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ATIS —

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RADIO

RADAR

CONTROLS

THE JOB

You work TOWER and GROUND together. Click or tap an aircraft on the map, or its strip, to fill the callsign, then type the clearance into RADIO and press Enter.

The dropdown lists the legal next words: arrows to pick, Enter to send. The route draws on the map before the clearance goes out, flashing while it is incomplete and solid once it reaches the target. Drag the field to look around. The mouse wheel zooms, and two fingers pinch to zoom on a touch screen.

INSTRUCTION SHAPE

Every clearance is the same three slots: [CALLSIGN] [TARGET] [PATH]. TARGET is where the clearance ends: a runway hold, a gate, a stand, a ramp, or a pushback facing. PATH is the vias in the order they are flown, starting with the one the aircraft is already on.

Taxiway letters and runway numbers are the ones painted on the field. SHOW TAXIWAYS in the top right corner lights them up. Where two paths reach the same parking, swapping the last taxiway sends the route the other way, and both still end in the same place.

ICE306 19 K E N: Taxi to the hold of runway 19 via K, then E, then N. They hold short and do not enter. From an intersection the crew wants spare runway beyond the run they need; otherwise dest -19 to hold short (or cross).
ICE307 GATE 14 N E: Taxi in to gate 14 via N then E. Use STAND when that is what the strip shows.
ICE306 PSHBK SE: Push back to face southeast. A pushback has no path.

DEPARTURE FLOW

Gate to airborne is three clearances.

HOLD stops them where they stand, mid-push or mid-taxi. After a hold short, or a HOLD on a taxiing aircraft, RESUME continues the rest of the clearance. At a stand they leave on their own power there is no push: they request start-up, START approves it, and they call ready to taxi once the engines are running.

1PSHBK SE Push back. The compass point is the facing they stop in, not the direction of travel. N / NE / E / SE / S / SW / W / NW. Where a taxi line runs close to that facing, they finish lined up on it.
219 Q N Taxi to the hold of runway 19 via Q then N. They stop at the holding point.
319 CLRD TAKEOFF Cleared for takeoff. Issue it once they are holding at that end, or while they are still taxiing to it. Check the strip is empty. From an intersection the crew wants half as much runway again as their run, less when they are running late; from full length they always go.

ARRIVAL FLOW

An inbound is three clearances, from final to parking.

If the approach is not working, GO AROUND. MIN SPEED then RESUME SPEED buys spacing on final. If the runway will be free just in time, EXPT LATE lets them continue uncleared down to 50 ft.

119 CLRD LAND Cleared to land. Issue it while they are inbound on final for that runway.
2VCTE Q Vacate via taxiway Q while they roll. Add LEFT or RIGHT when the same letter exists on both sides of the strip.
3GATE 14 Q N Taxi to the assigned parking via Q then N. CROSS a runway in PATH if the route goes over one.

HOLD SHORT AND GIVE WAY

Prefix a taxiway or runway with - or -- to stop short of it. Type the dash in the PATH slot, or the TARGET slot, and the dropdown switches to HOLD SHORT / HOLD PAST.

Use a dot instead of a dash to also give way: . is - and .. is --. At a taxiway, after the hold the aircraft lets whoever is rolling that taxiway go by, then continues onto it. A runway never takes a dot: conditional crossings are not used in real ATC, so hold short and clear the crossing yourself. A gate, stand or parking area is never something to hold short of.

-Q: Stop before Q. RESUME then enters Q.
--Q: Stop at the first Q intersection and stay off Q.
-19 / --19: Hold short of runway 19 mid-route — the two mean the same at a runway. RESUME is then the clearance to cross.
19 .Q: Hold short of Q, let the traffic go, then join Q toward 19.
..Q: The same give way, holding at the first Q intersection and staying off Q.
BKTRK 10 -19: Held short of a runway while on another runway: there is no hold line, so they stop one width of the runway being crossed short of its edge.
-C -N --N14: Mid-taxi, on its own: add several holds to the route already cleared. Each one is taken in route order.
-19 mid-taxi: On a route already cleared with CROSS 19: -19 takes the crossing back and they hold short.

LINE UP BEHIND

19 LINE UP BHND holds the aircraft at the entry until the traffic ahead is out of the way, then lines it up. That is an arrival rolling past the entry, or a departure moving away from the line up point, whichever is the case at the time. Long form: BEHIND.

There has to be traffic to be behind, or the command will not take.

CROSSING A RUNWAY

CROSS 19 authorises the taxiways and fillets over that strip. BKTRK 19 is CROSS plus travelling the centreline, a backtrack. The number is the direction of travel: BKTRK 10 rolls heading 100, BKTRK 28 the other way.

Without one or the other, the hold line blocks the path and they stop there. Backtracking one runway over another still needs the other one crossed: BKTRK 10 CROSS 19.

SPLIT RUNWAY OPERATIONS

There is no command for this. You choose it by clearing landings and takeoffs on more than one strip. On a crossing layout (BIKF 10/28 × 01/19) that only pays if you can keep the intersection empty.

If you cannot protect the junction, keep a single runway. More traffic is not a reason to split.

WIND: ATIS / METAR. A strong wind on one axis makes the other strip a tailwind or a heavy crosswind. If only one pair of ends really works, stay on that pair.
CROSSING: Never two movements in the junction at once. Hold one short of the crossing, or wait with margin until the arrival has vacated past it, or the departure is airborne and past it.
SPACING: A stream of inbounds on one strip leaves no gap to launch on the other. Split when mixed traffic would otherwise queue and the next arrival is far enough that the crossing will be clear.
TAXI: Two active strips usually means more runway crossings. Budget CROSS and hold shorts on the ground routes, or the air picture looks fine while the apron locks up.

COMMAND LIST

Every line starts with the callsign. It is already filled in if you clicked the aircraft or its strip.

PSHBK N: Pushback. The cardinal is the facing at the stop. It includes start-up approval.
START: Approve start-up for an aircraft that leaves its stand on its own power and has asked to start. No pushback; they call ready to taxi when the engines are running.
PSHBK GATE: The tug pulls back into the stand. Only after a HOLD mid-push.
19: Taxi to the hold of runway 19 for departure. Too short from that entry still routes, with remaining/need in red — the clearance will not send. Need from an intersection includes the spare the crew wants (half their run again, less when they are running late); full length never asks for more than the run. Use -19 to hold short (or cross).
GATE 14 / STAND 63: Taxi to that parking position.
RAMP J: Taxi to a ramp (Arlanda's Ramp J); the stand on it is picked for them.
Q N: PATH vias. Name the taxiway under the nose when it is a proper run.
-Q / --Q: Hold short of Q / hold at the first Q intersection and stay off Q.
-19 / --19: Hold short of runway 19 on the path (the same thing at a runway).
.Q / ..Q: Like -Q / --Q, but give way to traffic on Q, then continue onto it.
CROSS 19: Cross runway 19 on taxiways and fillets.
BKTRK 10: Cross plus travel the runway centreline (backtrack), in the direction of that runway number.
19 LINE UP: Enter the runway and wait. If another departure is using that same runway number, they taxi up to the runway outline and hold short — not at the holding point — until it has been in the takeoff roll for 5 seconds. A different runway end does not hold them.
19 LINE UP BHND: Line up once the traffic ahead has rolled past or moved off the entry.
19 CLRD TAKEOFF: Cleared for takeoff. Long form: CLEARED TAKEOFF.
19 CLRD LAND: Cleared to land. Long form: CLEARED LAND.
VCTE Q [LEFT|RIGHT]: Vacate via that exit. Add LEFT / RIGHT where the same letter exits both sides. VCTE 28 vacates onto an intersecting runway. Long form: VACATE.
VCTE LEFT|RIGHT: Vacate first convenient left / right: the pilot picks the exit on that side. In the dropdown, each side's flyout (›) lists every exit on that side.
HOLD: Stop where they stand. Also stops a push or a tow. Before the takeoff roll, cancels takeoff clearance. A taxiing aircraft keeps its route: RESUME continues it.
LINE UP: After takeoff clearance, before the roll: cancel takeoff and line up and wait.
RESUME: Continue past the current hold short, or carry on after a HOLD. At a runway hold it is the clearance to cross.
ABORT: Reject a takeoff that is already rolling.
GO AROUND: Discontinue the approach.
CNCL LAND: Take back a landing clearance. They keep flying the approach, uncleared; they ask for clearance and go around at minimums unless it is given again.
EXPT LATE: Expect late landing clearance. An uncleared inbound stops asking for clearance and holds off the go-around until 50 ft. Long form: EXPECT LATE.
MIN SPEED: Minimum approach speed. RESUME SPEED to go back.
TOW 50: Tow back up to that many metres (max 300), along the trail they came.

TWRSCORE

THE NUMBER

TWRSCORE in the top bar rates how you run the tower over the whole session. It starts at 80. Around 100 is a tower that runs on time and by the book; above that is something extra. Below 50 the operation is in trouble.

It appears once the first few departures and arrivals are done. The arrow beside it shows where it is heading against the last minute. Click it for the details.

EVERY FLIGHT

Each flight is judged when it is done with you: a departure once it is airborne, an arrival once it is on blocks. Pushed on time, a short taxi with no stops for nothing, airborne or parked when the schedule says. The score follows how your recent flights went, so one bad flight fades as good ones follow.

Only what you control counts. An arrival the sim brings in late, or weather that sends one around, is not on you. A late flight you hold back is: it counts against you while it waits, not only when it finally goes.

SAFETY FIRST

An occupied runway on short final, two aircraft too close in the air, departures released too close behind each other, traffic braking hard for each other on the ground: these take the score down at once. It climbs back over the next minutes, but a serious one also caps how high it can go.

That cap lifts slowly, one clean movement at a time, and never all the way within the session. Clearing onto a runway that is not free is noted even when nothing comes of it; if it ends in a go-around, it costs more.

STAYING AHEAD

Clearances given before they are needed keep traffic moving: LINE UP BHND, a takeoff clearance before the aircraft has stopped, EXPT LATE while the runway is busy, a taxi route before the aircraft has to stop. When it works, it is rewarded a little.

When it does not, it costs more than playing it safe would have. Being early is good; being early and wrong is not.

BUSY OR QUIET

A busy hour forgives a little more delay and a longer queue than a quiet one, where there is no reason for anything to wait. Safety is judged the same however busy it gets.

There is no trick to a high score. Run the tower the way a good controller would, and it follows.

THE PANEL

Click the score for the panel: accidents, incidents and remarks so far, where the last flights gained and lost, and FEEDBACK: what needs your attention right now, and what is going well.

DISPLAY

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TWRCTRL air traffic control simulator