LOWI Primer

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About this Document

This document is intended as training and reference material for controlling Innsbruck Airport (LOWI). It covers the stations LOWI_TWR and LOWI_APP. This page is work in progress. If you are controller: Feel free to discuss and edit.

If you are a Pilot: The page LOWI for pilots is a better source for you, with more info on flying airplanes and less on controlling.

AIRAC status is 1407 from November 2014.

Speaking of AIRACs: There was a time when airacs lacked all SIDs with partly visual departures (Navigraph left them out). If you happen to have this problem: then paste the following code into your .ese file to make it work. Place the following code to the LOWI SIDs (look for RTT2X and paste it there): 

SID:LOWI:08:RTT2Z:RW08 AB D0OEJ D0OEJ RTT
SID:LOWI:26:ADIL1H:RW26 RUM AB D0OEJ INN ADILO
SID:LOWI:26:KOGO2H:RUM D0OEJ RW26 AB RTT KOGOL D0OEJ
SID:LOWI:26:OBED2H:RW26 RUM AB D0OEJ D0OEJ RTT OBEDI
SID:LOWI:26:RAST3H:RUM RW26 AB D0OEJ D0OEJ RTT RASTA
SID:LOWI:26:RTT1Y:RW26 AB OEV13 RTT
SID:LOWI:26:RTT2H:RW26 RUM AB D0OEJ D0OEJ RTT
SID:LOWI:26:UNKE1H:RW26 D0OEJ RUM AB UNKEN RTT D0OEJ
SID:LOWI:26:MOGT1H:WI505 WI506 WI507 WI802 MOGTI

SID:LOWS:15:NEMAL1V:D099L NEMAL
SID:LOWS:15:PEREX3V:SI SBG D144L D144T PEREX
SID:LOWS:15:SIMBA6V:D099L SIMBA
SID:LOWS:15:TITIG2V:SI R226 TITIG
SID:LOWS:15:TRAUN7V:SI R226 TRAUN
SID:LOWS:15:LNZ6V:SI D099L LNZ

For convenience, the missing code for departures in LOWS (Salzburg) is there too - 6 departures must be patched.

This also means that there are some pilots with younger AIRAC cycles not able to fly the most basic departure routes. You could counter their unavailability by pointing out the charts: Most missing departures are non-RNAV - pilots could and should fly them by hand and radio navigation.

General

Location

Innsbruck is one of the most thrilling airports to fly from and to, for various reasons:

  • It is deep in the Inn valley, surrounded by mountains as high as 8000ft (to the north) and >10000ft (to the south and West). This means that approach is particularly long, and flying is limited to a narrow corridor. Turns within the valley need to be done with minimum speed and maximum bank to avoid rock.
  • The runway is somehow not in line with the valley, so approach and takeoff is not straight-in-or-out. Instead, the last part of approach and the first part of departure is visual only.
  • LOWI has peculiar wind conditions - "Föhn". This is a very strong and gusty southerly wind. Under these conditions, aircraft usually perform a "special Föhn" departure and arrival to avoid vomiting passengers and heart attacks. At VATSIM, these conditions cannot be simulated, but some local pilots love to fly it.
  • The runway has no complete adjacent taxiways for entering and exiting - Departing (and sometimes arriving) aircraft need to backtrack on either side, which takes time and makes Tower controlling a real thrill.
  • X-Plane 9 has LOWI as (nice) standard scenery, which provokes many X-Plane newbies to try out their skills here - thrilling experience for controllers, to be polite.

Airspaces around LOWI

As Innsbruck is deeply buried in "the canyon",

  • CTR (for LOWI_TWR) reaches up to A9000ft (mark: actual altitude, not FL). If no higher ATC is available, then Innsbruck Tower controls up to A11000ft.
  • Also, LOWI_TWR takes care of three adjacent SRA: Innsbruck I (west), Innsbruck II (east) and Innsbruck III (south). TWR competence reaches from SRA bottom (6000ft for Innsbruck 1, 8500ft for Innsbruck II, 7000ft for Innsbruck III, but at least 1000ft GND in all 3 cases) to 9000ft - above is APP. VFR route points are mandatory reporting points (full triangle, except Golf) and TWR shall be contacted 3 min before reaching the initial entry point (M1, N1, W1, Brenner), even if those points being located outside the CTR.
  • LOWI_APP airspace (Area Tirol) reaches up to FL165. The airspace above is delegated to EDMM.
  • If LOWI_APP is offline, LOVV_CTR takes over (but does not take over the delegated part, so if EDDM is offline, >FL165 is UNICOM.

For VFR, Innsbruck is quite a paradise. There are certain limits, under which VFR aircraft need not call in. See Alex Arlow's overview for this: [1]

Blue is CTR: knock before you enter :-). Orange is SRA: Knock before you enter, but only above a certain altitude. Red is CTA with free VFR up to 9.500ft.

The tricky thing is: RTT NDB is outside the orange airspace: any VFR aircraft can mess around there without contact - a nightmare. Luckily, most VFR pilots don't know and register nicely. As usual, they get traffic information. IFR gets separated.

EDIT Dec2014: There are new airspace rules which will be implemented soon 2015: There are no more SRA, only TMA (Transponder mandatory Area). Stay tuned for spaces and regulations! See Alex Arlow's posting for details.

What that means for controlling Innsbruck

  • Approach and go-arounds are especially long - a go-around adds up to 15min to flight time - more, if there is a holding to queue through.
  • For LOWI_APP, the thrilling thing is to judge distances and speed far in advance: Decisions to merge different approaches (LOC DME East, West and ELMEM) are made some 5 minutes before planes actually meet, with little room for manoevre once the decision is made.
  • For LOWI_TWR, there are many thrilling things: 1) you have tasks to do which other airports have a director for: final approach sequencing. You have to slow aircraft or speed them up, issue altitude restrictions and more (you won't give them headings - too much rock around, but rather orografic directions based on terrain). 2) Your task on top is to manage the merger of different approaches with VFR and more. 3) You even have to manage go-arounds, as they regularly get in conflict with your arrivals. 4) You don't have DEL or GND - you do it all. It's really fun to do!

Airport

(see the aerodrome chart, which is [here].)

X-Plane Screenshot of LOWI

Apron

  • The far eastern part is for General Aviation (GAC East).
  • The middle part of the apron is for larger birds.
  • Local General Aviation is at the very Western part in front of Hangars I, II and III.
  • In the western part is a "cutout" in the grass. On earlier charts, this was marked as helipad. Some choppers still use it - clarifiaction ("heliport in front of hangar II") is recommended Otherwise Copters are parked like planes (depending on size) at the main apron.
  • Rescure and police helicopters operate from the "Flugrettungszentrum" (ICAO: LOJO), which is south of hangar III and the engine run stand. Local pilots pronounce it "Lojo" and don't spell it. LOJO is not part of any standard package. Giannis MSFS add on scenery has it, and X-Plane has it too.
  • Apron, hangar and LOJO is not under TWR control. Therefore, you treat it as any space within CTR. you tell QNH, wind and "takeoff/landing at own discretion", as long as they don't interfere with runway or taxis.
  • The Apron has no predefined "stands" in real life. In real life, aircraft are handed off to the follow-me car. As there is no car at VATSIM, "taxi to stand of your choice" is best, maybe added by "in the western part of the apron" - for some mysterious reason many aircraft tend to log on in front of the tower in the eastern part.

Holding points

  • A on the taxiway A towards rwy 08
  • B1 (facing east before turning into B) and B2 (facing west, before turning into B). They are not shown on the VACC charts and not included in FS or X-Plane standard scenery, but included inGiannis LOWI scenery for MSFS. Don't expect pilots to find it. "Holding point B" works perfectly.
  • L holding point is relevant for the GAC parking.

Runway and around

  • Runways 08 and 26 both have turnpads. Some pilots report "runway vacated" when standing on it, so be aware.
  • North of the runway is taxiway Y which is grass and for light aircraft and gliders only. Some pilots think it smart to use it if they miss taxiway A to vacate, or the adjacent "Schleppweg" (glider tow track) with 767's and are a bit surprised.
  • About 1,5nm final rwy 26 is the rooftop helipad of the hospital (LOIU). This is not part of the MSFS or X-Plane standard scenery. If the helipad is occupied, inform arriving aircraft about a "floating" heli: "traffic information: stationary helicopter at the hospital helipad at 1.5nm final".

Runway configurations

Be aware that a few factors restrict runway configurations, mainly: position in the valley and pilots' ability.

  • Easiest config is outbound 08 / inbound 26. (Almost) all pilots can handle this. But this is an opposite configuration. In this case, outbound taxi is via A, and backtrack is only granted as long as arriving traffic is above RTT. Always instruct maximum rate of climb. This is the least efficient configuration - only at low traffic.
  • Once this configuration gets crowded, you can only speed up lineup by 1) clearing departing traffic to A, 2) order arriving traffic short landing and hold on the runway short of A, and if this works out: 3) order departing to lineup and backtrack 08 and 4) order arriving to taxi via A to the apron.
  • If short landing does not work out, the arriving has to taxi all the way back to B while the departing lines up and backtracks. You can ONLY do this, if the approach sequence is free from RTT to final - outbound aircraft need the airspace.

  • Best high traffic situation is 26 only. Departing aircraft taxi via B and circle (with max rate of climb) and reach AB with 6000ft or more. With this, vertical separation is guaranteed and you can get aircraft in and out fast. Bear in mind that you need at least 5nm arriving distance in case a landing aircraft overshoots A. You need at least 7nm arriving distance to get an aircraft off the ground (backtrack and takeoff).
  • The most common mistake is to forget a LOC DME West arrival which kisses the departing aircraft in mid-air. Also, you won't allow ELMEM arrivals (they go to 08 only).
  • Föhn config is 08 only. Arriving aircraft must be able to circle. You need at least 10nm arriving distance to bring an aircraft out.
  • High traffic trick: Best procedure is to issue backtrack 08 early, and at the moment the arriving aircraft is turning left at AB for circling, takeoff clearance is given (and the next arrival must be 10nm before AB to provide vertical separation).
  • High End config is "as it comes": Use 26 and 08 as it fits, instruct pilots "on the fly" to change arrival runways and the like. Usually it is less efficient than 26only, but much more fun for pilots and controllers.

VFR Traffic

LOWI VFR routes old and new

(see the VFR chart, which is - hooray! courtesy of AustroControl and free for VACC users: it's here). Important: There are new routes as of March 8th, 2012. Expect pilots turn up with charts of either generation, so we recommend: Try the new charts right away and see if the pilot knows what you mean. If he doesn't, the following changes apply:

  • M1 is the old E1
  • old E2 is omitted
  • M2 is old L2
  • M3 is old L3
  • old A is omitted
  • The eastern arrival route (new: M1-M2-M3) is old: E1-L2-L3.
  • Approaching from F, the old arrival route L (L1-L2-L3) is now F-M2-M3, but beware: F-M2 is close to the LOC DME east, as VFR pilots need to climb to 7500ft.
  • West: G and I are new, so you might avoid it.

See this graph with the new chart and its changes from the old. If you look for the old chart for historical purposes, it's still [here].

The MIKE route has a dog's leg to the south at M2, and the reason is: this is the best way to separate IFR from VFR. LOC DME East passes this route high above just before M2, crossing from the southern slope to the north (at AB NDB), so VFR aircraft cross underneath and enter the VFR holding south of the airport. This VFR holding south of the airport is even better, as it does not conflict with IFR aircraft circling 08.

You can be very eclectic with VFR traffic (means: do-as-you-like) to get them apart from IFR traffic. Order them to fly to the southern or northern slope of the valley, to circle on the spot where they are, to climb or descend. The defined routes are made for maximum separation and are good to clear if you have a lot of traffic (as you don't need to think about them).

Radio Communication Failure for VFR

Caution: RCF procedures are not at the VATSIM charts - expect pilots to do what they want (you might tell the pilot via pm what he/she can or should do). In real life for VFR, the following rules apply:

  • If RCF occurs before CTR entry clearance, then the pilot has to divert to an airport in uncontrolled airspace.
  • If RCF occurs after CTR entry clearance, then the pilot follows this clearance and lands. ([reference]. If the clearance is until holdings, then in real life aircraft continue to a predetermined position near the airport (for west: north and for east: south) and await light signals (or, in fact: they call in by phone).
  • At VATSIM, expect RCF aircraft to do what they want, really... :-)

IFR Traffic

Approach

Innsbruck has two standard directions to fly in, but "standard" is relative: They are not straight-in and you have to land visually on rwy08 or rwy26 (either approach).

Visibility limits

Visibility limits are up to pilots. If visibility in the valley is below minimum standards for the approach, it is a courtesy to pilots to warn them, but decision is up to them. If you want to be "as real as it gets" and follow the Austrian AIP, then you could restrict...

  • no IFR departure below ground visibility of 1.500m and ceiling below 1.300ft above the ground (which makes about 3.300ft altitude)
  • no IFR Special performance departure below RVR 300m.

IFR from the East

LOC DME East Approach

LOC DME East approach

This approach is most popular, but many pilots don't read the charts and surprise both themselves and controllers: It has a glideslope, so many aircraft think it is an ILS and discover their mistake some 100ft over ground that they head for the apron and a hangar - funny manoevers happen.

  • Minimum visibility is 6 miles, as AB NDB is MAPt. For Tower controllers that means: Clear them to land at AB NDB, or issue "expect late clearance" so that they can continue. If pilots don't hear anything, they must go around (noone does in fact...)
  • Go-around is a challenge: Continue slow and max. rate of climb until D1 OEV, do a steep turn left and back to AB NDB, a 74° climbout until D14 OEV and then a straight RTT into the holding - expect pilots do whatever they can.

Special LOC DME East approach

...is the same as the "normal" LOC DME East, but has a lower decision heigt and a Missed Approach Point which is the outer marker. You see it on the visual approach chart: the dotted line from the outer marker to the south. The special approach is granted on pilot's request, and as the pilot has to monitor decision height, controllers can grant it and ignore the rest.

  • As MAPt is the outer marker, minimum visibility should be 4,1 miles or more.

RNAV 0.3 (RNP) arrival

This approach is very rare and on pilot request only (as aircraft have to be equipped with GPS with 0.3nm accuracy). The approach is very similar to Special LOC DME East approach.

  • This approach leads into rwy 26 only (and might mess up your runway config, if you have 08). Go-around is different - a RNAV turn in the upper Inn valley and return to RTT NDB. If you discover that landing on 26 is impossible, you have to ask the pilot "able for visual approach circling 08", and if the pilot is unable, issue a go-around.
  • This arrival is the least to close when visibility declines: 2 miles is enough.

In fact, most virtual accidents happen on go-around. Those who most likely evade the mountains - if they don't hit a fellow airplane - are those who visually climb out the valley.

LOC R RWY 26 arrival

A relatively new approach is the combination of two:

  • descend the LOC DME East approach,
  • but the go-around is an RNAV go-around.

The clearance phrase is important: 

"Cleared Localizer DME East Approach, followed by RNAV missed approach."

(there is no "Localizer RNAV Approach"!)

IFR from the West

LOC DME West Approach

LOC DME West approach

A challenge! A steep descent from KTI NDB over the airport to AB Locator at 5000ft, where a tight (visual) right turn leads them into the position of either continuing towards RWY26 or RWY08. Pilots who don't read charts think that this approach directly leads to RWY 08. Some dive for it when they have runway in sight and end up with 300kt on short final.

  • This approach has no glideslope (hence LOC). Aircraft have to descend with v/s on and good planning. The descent levels at 5000ft above the outer marker with a few extra miles level flight for landing configuration (as aircraft will likely hit mountains flying the right turn with approach speed).
  • Caution: LOC DME West is not part of standard FS2002 and 2004 (but included in X-Plane 9). It is recommended (to APP) to check in advance, if the pilot is able to do this. Some pilots use the back course of LOC DME east with smashing results.
  • This approach is challenging to anyone doing it for the first time. Descent is steep and you need to be at 160kt for the right turn - in fact, you almost need to prepare your aircraft for landing (flaps, gear, speed 160kt) above KTI. If APP wants to be polite, he/she tells them and sends them into the KTI holding until speed is down. If controllers notice aircraft rushing down with more than 250kts, prepare to extend their downwind eastwards or order go-around.
  • Go-around is the 08 departure route: 67° inbound OEJ and 65° outbound OEJ, past RTT NDB and a left turn into RTT holding.
  • In real life, many pilots request "visual" before KTI, when they see the Inn valley is clear of fog or clouds and proceeding visually to RWY in use (yes, this may also include a downwind for RWY 26)As ATC, you can clear this on pilots request if it fits you.
  • Visibility has to be extensive: LOC DME West is for cloud-breaking purpose only: cloud base must be more than 5000ft and visibility depends on aircraft category: 3km for A and B, 5km for C and D.

Special LOC DME West approach has been omitted by july 2011. Use standard LOC DME West approach.

RNAV 08 GNSS via ELMEM

Since this "visual" has become the rule for more and more aircraft, there is a new RNAV arrival via ELMEM covering exactly that, and it's quite thrilling: It starts at ELMEM and descends on GPS waypoints into the valley, and then pilots follow visually the GPS route until they have runway 08 in sight.

  • This approach is for cloudbreaking only: ceiling must be above 4100ft and visibility 5km or more.
  • Go-around is down the Inn valley via MATF (Missed Approach Transition Fixes): Aircraft are requested to fly fixes to avoid hitting scenic scenery. WI103 is equivalent to the outer marker and WI001 is RTT NDB. Aircraft should fly a teardrop entry (expect 80% not to know what that is).

Visual Landing

All approaches meet at AB NDB. From there, there are two ways to the runway (see the visual approach chart):

  • rwy26: For east approach, this is almost straight-in. For DME west approach, a steep right hand circle into final.
  • rwy08 For DME east approach, aircraft turn left towards INN and then circle right onto final. Aircraft almost need landing speed to turn. For DME west appraoch, aircraft turn right hard (landing speed!) over AB, fly left downwind as DME east approach and then turn right into final.

Caution: It is TWR's responsibility to merge traffic arriving at AB NDB!

How to clear approaching aircraft to land

Approach is long, and many things happen in the meantime. Therefore, we recommend step-by-step clearances:

  1. Clear all approaching aircraft with a reporting point which is no later than the MAPt:
  • For LOC DME East and West, this is AB NDB
  • for RNAV West, it's "runway in sight".
  • for RNAV East, it's WI003, the outer marker.
  1. For rwy26 (and RNAV West to 08), clear to land, if possible (or issue "expect late clearance"). Aircraft should not continue approach if they don't receive any of the two.
  2. For circling approaches (DME west and DME east->rwy08) clear "visual circling rwy 08, report crosswind", and then clear to land.

This step-by-step clearance helps to stay flexible if the situation changes. You could clear to land at fist contact at 13.000ft, but the plane would still be flying for several minutes before touchdown and you might have forgot, who has a landing clearance and who not.

One example with two aircraft: LHA123 is just after RTT for LOC DME East approach, and LHA456 at KTI for LOC DME West approach. As LHA123 from the east is lower (RTT is 9500ft) and nearer (15 DME AB) than LOC DME west (FL130 and 18-20 DME AB), it will be first in: 

LHA123: Innsbruck TWR, gutn Tach, Laipzich Air 123 LOC DME East established.
TWR: Leipzick air 123, servus. Contintue, Wind 230° 4kt, runway in use 26, report AB NDB.
LHA123: will report AB, LHA123.

Next is LHA456, who has to slow down (as 3-5nm is not enough separation). Anyway, for LOC DME West approach aircraft should prepare their aircraft at KTI for landing: Speed down, flaps down, and they might need speedbrakes up. It is a good precaution to tell this to pilots: West approach is steep and many aircraft get too fast and are in too early. The only way out would be a go-around to RTT. Caution if you order speed down: There might be an aircraft behind - yu might need to check with APP. 

LHA456: Innsbruck TWR, hallo, LHA456 LOC DME West established FL130.
TWR: LHA456, servus, continue, wind 230°4kt, runway in use 26, reduce to landing speed, report AB NDB.
LHA456: Reducing to landing speed, will report AB, LHA456.

Now LHA123 is near AB and sees the runway. He gets and clearance to land, plus traffic info, as the other acft is roughly 5-7nm away, head-on and above: 

LHA123: LHA123, AB.
TWR: LHA123, traffic info: Approaching company airline on LOC DME West at 12 o'clock, 7000ft. Wind 230°4kt, rwy26 cleared to land.
LHA123: Traffic in sight, rwy26 cleared to land, LHA123.

As LHA123 is away from AB, LHA456 gets clearance further on into final, plus traffic info, and after reporting final, clearance to land. If there is no traffic around, TWR could clear him to land at once (Strictly speaking, both aircraft could meet at AB, as LOC DME West approach should be about 700ft higher. But it's close and you will have problems with lateral separation at final anyway. If you produced such a problem, you could order LHA456 circling 08 at landing speed and hope that LHA123 vacates quickly). Most likely, LHA123 is still busy vacating the runway, so landing clearance is not possible yet: 

TWR: LHA456, approaching company acft on LOC DME west 6000ft at your 12 o'clock position. After AB continue visual circling rwy26, report final.
LHA456: Wilco, traffic in sight, LHA456.
LHA456: LHA456 on final 26, runway in sight.
TWR: LHA456, wind 230°4kt, rwy26 cleared to land.

Tricky conflict situations

Arriving/departing too close

Sometimes, aircraft come too close to each other, departing from 08 and arriving LOC DME East (mostly because aircraft climb out fast-and-low). What can you do?

  • Giving the arriving aircraft go-around most likely increases your trouble: flight paths cross.
  • You could order the departing aircraft max rate of climb. This helps, if the pilot really does it, and if it's not a whale (747 or so). If it doesn't, you are still in trouble.
  • You can order the departing aircraft visual climbout down the valley with max altitude well below the glidepath. Expect some funny reactions when you attempt to change a MD81 to visual.
  • Most elegant solution: Separate both aircraft visually. To do this, ask the landing aircraft if he is able to perform visual landing left of the localizer. If yes, then clear him visual approach left side of the localizer and give traffic information. Then, clear the departing aircraft visual climbout left side of the valley and give traffic information. It may be a scary moment if two A320 pass in mid-air in the narrow valley, but it is legal.

It could sound like this, assume that DLH1 is departing and AUA2 is arriving: 

LOWI_TWR: AUA 2, are you able for visual approach left of the localizer?
AUA2: Affirm able for visual approach left.
LOWI_TWR: AUA, cleared for visual approach left of the localizer, traffic information: departing A320 at your 1 o'clock position, passing right, confirm in sight.
AUA2: visual approach, traffic in sight, AUA2.
LOWI_TWR: Lufthansa 1, cleared visual departure left side of the valley, traffic information: arriving B737 passing right, confirm in sight.
DLH2: visual departure left side, traffic in sight, DLH2.

Departing aircraft are too slow lining up

Sometimes, departing aircraft are too slow lining up and backtracking for takeoff. This will result in arriving aircraft on an occupied runway. What can you do with an approaching aircraft?

  • You instruct departing aircraft to hold position and instruct arriving traffic to go around. But go-around in LOWI is very long and time-consuming: Aircraft have to climb all the way to RTT and back.
  • Most elegant solution: If the pilot is able for visual manoever, you can offer him to circle visually and re-enter final. Once the aircraft is on downwind, quickly push departing aircraft out. That could sound like this:
LOWI_TWR: DLH1, hold position, say again: hold position, acknowledge.
DLH1: Holding position, DLH1.
LOWI_TWR: AUA2, go-around, say again: go around, or alternatively visual left traffic pattern, report intentions.
AUA2: Requesting visual traffic pattern, AUA2.
LOWI_TWR: AUA2, cleared visual left hand pattern at 3500ft or above, report ready for base turn over AB, 
(after AUA2 is away over the airport:)
LOWI_TWR: DLH1, cleared for immediate takeoff, expedite.

This manoever works with 26-only and 08-only, just the other way around.

Aircraft meeting at AB NDB

Absam NDB is the focal point for almost every approach and departure - things can get really nasty there.

It could either happen, that two aircraft from LOC DME East and West meet head-on at AB NDB, or that a go-around from 08 kisses an arriving aircraft from LOC DME West. Both are really difficult situations which they cannot resolve on themselves, as TCAS might advise them to something that terrain won't allow (and TCAS is first, ATC is next). What can you do? First, you have to bear in mind, that any solution might cause the next problem (and you have a chain of problems to fix). Second: These are the options.

  • Clear the LOC DME West arrival to level off at 6000ft. The LOC DME East arriving will pass well below. There is still room to descend while turning into final. Anyway, you might need to clear the LOC DME East for rwy26 and the West for rwy08 for separation.
  • If you notice the problem early: Make one aircraft reduce to landing speed - better the East arrival, as the West descent is steep. Bear in mind that this might mess up arrival sequence behind.
  • If a go-around gets in the way of an arriving LOC DME West: Separate vertically by clearing the go-around at 5000ft until AB NDB and the arriving at 6000ft. Bear in mind that restricting the go-around in altitude might make the next mess with following arrivals on LOC DME East. The brute force solution is to clear the LOC DME West approacher a visual go-around at the Northern slope, while the LOC DME East go-around is cleared visually out the southern slope of the valley (you have to give them traffic information, and you have to separate them as soon as they are clear of peaks).

Bear in mind: These are really tricky manoevers. You need experienced pilots and controllers to do it.

Go-arounds

  • Go-around rwy 26 is a steep left turn and climbout to RTT.
  • Go-around rwy 08 is a straight climbout to RTT.
  • Go-around of RNAV 0.3 RNP arrival rwy26 is along waypoints into the upper Inn valley where the aircraft does a steep left turn and returns the approach path to RTT - Nobody flies this.

Go-arounds go all the way back to RTT - that takes a lot of time and could mess up the next arriving aircraft. If there are other landing aircraft on LOC DME East, max rate of climb is necessary. Some pilots don't do this and must be reminded.

To smart pilots, you can offer a visual circuit, leading them back to final via AB, see the section above.

Departure

All departures are cleared FL160. When things are busy, you might need to decide on short notice if a pilot flies out 08 or 26, as some can only arrive 26 (and departing need to take 26 for spacing), and some can only depart 08 (and vice versa), and then Mirza comes along and ultimately wants to land circling 08 (:-). Controllers' delight are pilots who are able to change SID and approach at short notice. Controllers' headache are the others - in doubt, they have to wait on ground.

NEW Flight plan clearances

There is (almost) nothing special on flight plan clearances (which are done by TWR, there is no DEL in Innsbruck), except:

  • If you clear a special performance SID (RTT1W, KPT1Z, RTT2Z, RTT1Y, RTT1X), you have to ask if the pilot (and his/her plane) is able to fly it. There are two reasons for an "unable": Not enough climb rate and no RNP0.3 equipment. If the pilot is unable, clear an alternative (RTT1W & RTT2Z->RTT2J, KPT1Z->ADILO1J, RTT1Y & RTT1X->RTT2H).
  • Visual departures: put a note in the text field so that Approach knows, where he/she is up to. You might want to coordinate with APP before. Generally, all special departures are on pilot's request.
  • Be careful on the initial climb altitude: Standard clearance is FL160. If an aircraft has a lower RFL, then this makes no sense, but take care: There are mountains around and you need to clear to the minimum safe altitude - if the RFL is too low, then you have to amend the flight plan to the next suitable FL. What is the minimum safe altitude and the matching FL? You have to calculate:
  1. KPT departures have MSA 11.500ft. You have to add the safety distance (like you calculate TA and TL according to QNH: add 0 to 3000ft) and then take the next matching flight level. Example: For QNH 1019, it is: 11.500ft+1000ft=12.500ft. The next matching flight level (to the west: even) is FL140.
  1. ADILO departures have MSA 13.000ft, and you have to calculate accordingly. For QNH 1019, it is: 13.000ft+1000ft=14.000ft -> FL140.
  1. All departures east via RTT have the standard 11.000ft TA. Add the safety distance and you have the miminum RFL. For a flight to LOWS at QNH 1019, you take: 11.000ft+1.000ft=12.000ft -> FL130 (east=odd).

For information on TA and TL, see the Transition_Altitude_and_Level glossary !

Departure Rwy 08

08 is the "easy" way out, but don't expect it to be easy for controllers, as the SIDs can conflict with LOC DME East approach. If you don't have inbound traffic, the standard departure routes are fine. If you have, there are alternatives.

Some pilots are programmers only - they only can fly what their FMC tells them :-) They might not have SIDs with visual parts in it. Strictly, you can deny departure. There is no RNAV departure for runway 08.

Standard departure routes 08

RTT2J, OBEDI2J, RASTA3J, UNKEN1J, KOGOL2J all have the same pattern: out on runway heading, following the 067° OEJ in- and 065° outbound radial until 9.500ft, then a turn onto their next waypoint. If they are too low at RTT, they must fly by RTT to the right and then do a left turn back to RTT. APP will (and should) issue a direct order when the aircraft is clear of peaks.

Danger: All this SIDs conflict with LOC DME East approach, as climb rates are too low for vertical separation. If you have a LOC DME East inbound aircraft, then you must issue "max rate of climb" (and hope that aircraft can and pilots do), or reclear to RTT1W departure: It has a steeper climb rate and approach paths don't overlap - they just cross at approx. 7DME OEJ.

Also, some pilots don't have OEJ (which is not part of the Standard MSFS scenery), and they most likely fly anything to RTT.

Heaven knows what RTT2Z is really here for - it is identical to RTT2J. Any ideas? Please let me know.

Special SIDs 08

  • RTT1W is a rocket departure: similar to RTT2J, but a steep climb rate (8.2%min.) and passes LOC DME East - first to the south, and then above. Aircraft should have 5.000ft at AB (just about enough to separate from LOC DME East, coming in at 4.300ft). If pilots don't climb enough, you are doomed.
  • ADILO1J: ADILO1J has a steep right turn after OEJ and needs a double climb rate than the "standard" SID via RTT. As precaution, TWR should check with the pilot if able.
  • KPT1Z has a higher rate of climb - pilots have to confirm.

Visual climbout 08

  • Sometimes you notice too late that a departing jet darts out at 250kt and too low climb rate, AND you have a LOC DME east inbound aircraft. What can you do? separate them visually left-around. Let the departing aircraft fly out on the left (northern) side and let the arriving aircraft continue on the LOC, which is on the southern side. See the "tricky conflict situation" section above for details.

Departure Rwy 26

Same here: Some pilots are programmers-only and can't fly what their FMC does not know. For runway 26 there is a remedy: If you are nice, you can clear them a visual departure to RTT and then to resume their route. Or you clear them RTT2X (GNSS RNAV only, see below, and only for runway 26).

Standard SIDs 26

  • RWY 26->RTT: RTT2H, OBEDI2H, RASTA3H, UNKEN1H, KOGOL2H have a common pattern: Max rate of climb on runway heading, a slight visual right and a steep visual left onto the 67° inbound and 65° outbound LOC OEJ. Expect pilots not to find OEJ (not part of the standard MSFS scenery) and fly out visually. If you have inbound traffic on LOC DME East, minimum climb rate is too low - use the special performance SIDs or order "max rate of climb".
  • ADILO1H has the visual circle left and a steep right turn after OEJ and needs a higher climb rate than the "standard" SID via RTT (6.5%). Aircraft should have enough altitude above AB NDB (5.000ft) to separate from LOC DME East approach, but you never know.

Special SIDs 26

  • RTT1Y is the max-rate-of-climb-alternative for the standard SIDs, if you have inbound traffic on LOC DME East. Aircraft must climb 5.4% or more and are clear of arriving traffic at AB NDB. The SID also passes AB slightly south and then crosses the approach part to the north (but not enough for IFR separation).
  • RWY26 RNAV 0.3: Only for equipped aircraft. This route flies up the Inn valley along waypoints, turns around and flies back to WI001=RTT. In practice, aircraft fly this route with max rate of climb until clear of peaks and then a direct routing - the rest of the route is backup if anything goes wrong. On pilot's request only.
  • Based on this RWY26 dep is the MOGTI 1x departure, which requires the same equipment and special performance.
  • There is a new MOGTI1H departure (GNSS). Aircraft fly visually up the Inn valley and at WI802 then turn to MOGTI. Nice departure to the west, as these aircraft are away quickly. This departure is only on the Austrocontrol charts yet. The patch for the .ese file at the beginning of this page covers it too.
  • Some pilots come along with the departure to ELMEM (ELMEM1H). The departure is similar to the MOGTI1H, but continues at WI802 to ELMEM and was only in use for around 1Q 13.

Visual

  • RWY 26 visual: Aircraft fly up the Inn valley until clear of peaks and then directly to their next waypoint. This departure often "happens": Pilots head for ADILO or KPT and forget that they have to turn twice. Instead of reminding them (then they turn too late and smash the mountain below KTI), you can reclear them "visual climbout west" to avoid even more trouble (controllers' benefit: They are out of the way then!)

Common mistakes by pilots

  • To RTT, many pilots tend to depart fast-and-low instead of slow-and-high. If you have arriving traffic at LOC DME East, then remind pilots (2, 3 times) of a max rate of climb. If they have 5.000ft at AB NDB, they climb enough.
  • On rwy26 departures, some pilots turn right instead of left, doing a CFIT into the Martinswand; the reason is that the left turn is slightly more than 180° and many autopilots (like the x-plane standard AP) turn the shorter side. In reality, a pilot with activated autopilot at that stage ends in a coffin or in jail. IF pilots fly out somehow strangely, it is a good idea to confirm "visual climbout west", as vectoring usually worsens the situation.
  • Some pilots do not understand that ADILO1H has a left turn towards OEJ and a right turn towards INN and end up with visual climbout. Not your problem unless you have VFR traffic in the W or N corner.

Föhn procedures

"Föhn" procedures are at pilot's request. Rarely used at VATSIM, as simulators can't simulate the strong (5-20kt) and gusty (20-40kt) winds. Local pilots like to do it for fun, so you should know it. The wind situation at Föhn is tricky: Wind breaks in through the Brenner valley from the South and (with escalating Foehn) drifting down the northern slope, dividing over Innsbruck to the West AND the East. As the airport is west of the city, local winds at the airport are from calm to easterly, where everything a bit higher up is full of gust and windshear. People will need vomit bags and pilots need good nerves.

Föhn operations lead to rwy08only and are visual only (with Föhn, view is excellent).

  • Arrivals descend high along the northern ridge between 8000 and 5000ft, were turbulence is least. West of the city (sometimes as far west as Seefeld!), aircraft dive for base and final rwy08. There is no standard circling 08, as it would lead aircraft right through the funnel of the storm around INN NDB.
  • Departures depart runway 08 and immediately drift to the northern slope, where pilots climb in the least turbulent air.
  • ADILO departures also climb on the northern slope and turn westwards above the turbulent area.
  • KPT departures are not recommended, as this SID turns very early = low in the middle of turbulence. The better alternative is standard Föhn departure (eastwards) and direct KPT above 10.000ft.

Spacing

The best thrill of the Innsbruck TWR controller is spacing. As Innsbruck has few and narrow approaches and backtracks on runways, spacing is well beyond other airports. As a rule of thumb, the following spacings are "conservative guesses" - you will most likely be on the safe side If you have the balls (and pilots can fly), you can shorten ist on your own risk :-)

  • arriving before arriving (same runway): 7nm (reason: you may need backtrack, if aircraft overshoot the exit). You could shorten to 3-4nm, if the aircraft is able for a short landing without backtrack (issue go-around when the first aircraft overshoots the exit).
  • departing before arriving (same runway): 7nm (reason: you need backtrack of departing aircraft). Make sure the pilot is at the holding point and ready to roll before issuing lineup clearances - 10 seconds make a difference. You can shorten to 4nm, if departing aircraft is able for intersection takeoff.
  • departing 26 before arriving rwy08: Arriving acft should be before AB NDB when departing aircraft takes off, and departing aircraft should have maximum rate of climb (they turn head-on, and departing aircraft should have 700ft more altitude!). Exception: If departure 26 is visual climb-out or RTT1X (departing aircraft flies up the valley and won't turn left).
  • departing 08 before arriving 26: Arriving acft should have D18 OEV (=just reported LOC DME established), departing aircraft should have maximum rate of climb.
  • departing 08 before arriving 08: For takeoff clearance, Arriving aircraft should be after AB NDB turning into downwind or before D18 OEV to avoid conflict. Watch out for the next conflict on LOC DME East - arriving aircraft should be D18 OEV.
  • arriving 26 before arriving 08: As the east-08 flies a visual circle, 5nm will fit.
  • arriving 08 before arriving 26: Well, if you really want to smash two aircraft in the middle of the runway.
  • Merging West and East approach: Both approaches meet at AB NDB, with West at 5000ft and East at 4460ft. There is one problem: vertical separation is not enough. Consider merging traffic with enough (7nm) horizontal separation over AB NDB. You could shorten this to 3nm separation, if the first plane ist LOC DME East and you clear him into 26 and the second ist LOC DME west and you clear him circling 08. You must be very fit if the LOC DME East aircraft does a last-second-go-around: The planes will meet head-on on downwind, and you have to separate them visually (both to their left) in seconds. How can you sequence KTI and RTT approaches? Look at the scope: Both descents are roughly the same distance to AB NDB. If you order same speeds, you can treat KTI as if the aircraft were above RTT. (In fact, KTI is a bit shorter, but aircraft need to turn above AB NDB, and that makes KTI about 1-2 miles longer, but you should not separate so tightly as you never know, how fast pilots will descend).

Do not hesitate to give speed orders if necessary, and if it does not mess up arrival sequence.

Reduced runway separation

None, as the risk is too high that an arriving aircraft overshoots the exit and needs a backtrack while the next aircraft lands and might do the same.

Radio Communication Failures for IFR

In real life, there are no predefined RCF procedures for Innsbruck for a good reason: In a narrow valley with lots of VFR and IFR traffic, this could have dangerous consequences if a big bird flies around without contact. There are company-specific rules negotiated between airline and Austrocontrol. As a rule-of-thumb, expect:

  • With RCF before approach clearance and handover to TWR: divert to a different airport.
  • RCF after approach clearance and handover to TWR: land - TWR should clear the way. Check, if the aircraft has received the runway to expect - if not: Where will it land?

There are no published RCF procedures on VATSIM charts, so expect pilots do what they want and expect the unexpected - most probably they will fly the approach they have been cleared or (if there was no clearance yet) they have filed (KTI or RTT). Most appropriate behaviour of controllers would be to clear the way. In real life, aircraft call in by mobile phone.

Transition Altitudes and levels

... are tricky in Innsbruck: Generally, Transition Altitude is 11.000ft (QNH), but it differs for East and West. Transition level is set by ATC. As a good rule of thumb, you should not mess up the two.

  • For the East approach, you might have a holding above RTT NDB, which starts at 9.500ft (as the approach). But you have a bundle of departures through RTT NDB - how do you fix this? The trick is: You leave FL 110 empty, where you shoot your departures through. If you want to do this, Tower has to clear initial climb rate of FL110, and holding stack starts at FL120. Any descending aircraft needs to descend from FL120 to 9.500ft altitude.
  • For the West Approach, the LOC DME West Approach starts at 11.500ft, and any holding is above 13.000ft (also QNH!). If you have a stack building up, what is the next FL? Either you calculate along QNH (if it's FL140), or you take FL150 and you are on the safe side.

Handoff

Handoff TWR->APP

Handoff from TWR to APP is best, whenever departing aircraft are conflict-free. It makes sense to have conflicting aircraft on the same frequency. Consider the example of an arriving LOC DME East (with APP) and a departing rwy08. They fly head-on. Either TWR gives the aircraft to APP (and APP monitors the possible conflict), or TWR waits for APP to receive the arriving aircraft (and TWR clears the conflict). Teamspeak is very handy at that situation.

Handoff is somehow tricky, if not all stations are online, because there are delegations. The hierarchy for handoffs is as follows:

Departure

Departures are straightforward, if Austrian upstream stations are online. If not, then handoff is tricky, as airspace above LOWI_APP is delegated to Munich. Therefore, handoff is handled in the following order: 

|------------------------------------------------|
| 0.  LOWI_TWR 120.10                            |
|------------------------------------------------|
| 1.  LOWI_APP 119.27                            |
|------------------------------------------------|--------------------|
| 2a. LOVV-CTR 134.15    | 2b. EDDM-APP          | for all others:    |
|     for all Eastbounds |     for all to EDDM *)|                    |
|---------------------------------------------------------------------|
| 3a. EDMM-K-CTR 124.05        | EDDM-C-CTR 133,67                    |
|     (Kempten)                | (Chiem)                              |
|     (ADILO-MOGDI, KPT)       | (for KOGOL, UNKEN)                   |
|                              |--------------------------------------|
| 3b. (all to EDDM-K-CTR if C-CTR offline)                            |
|---------------------------------------------------------------------|
| 3c. EDDM-R-CTR 132.550 (Roding)                                     |
| 3d. EDDM-A-CTR 129.100 (Allersberg)                                 |
|---------------------------------------------------------------------|
| 4. Unicom                                                           |
|---------------------------------------------------------------------|
  • ) Remark: Strictly, you must pass aircraft to München Center who will then hand off to München Approach. In practice, München Center has other things to worry than aircraft crossing their airspace for less than 2 minutes. Sometimes, Munich Approach takes them, sometimes not - enquire with partner controller, if online.

Anyone who wonders why there is no Italy in this graph: There are no SIDs from LOWI to the south: They pass over LOVV_CTR.

Arrivals

If no LOWI_APP and no LOVV_CTR is present, then aircraft are cleared by München FIR: 

TULSI arrivals are cleared at FL150 until TULSI, further released for descent at FL130 (they fly to RTT).
DCT ALGOI arrivals are cleared FL180, further released for descent to FL150 (they fly KTI).

The point to pick pilots up for LOWW_TWR is when established on the LOCs. If they call earlier (which they regularly do), then tell them to continue at their discretion and call back when established: 

LOWI_TWR: Leipzig Air 123, Innsbruck Tower, you are still outside my airspace, continue at your discretion and report when established on the localizer.

(you can be nice and add: "for your information: this means leaving RTT at 10.000ft with heading 210 ....")

(This reflects the LoA München FIR/Wien FIR from 1.11.2012)

Handoff to APP->TWR

whenever LOC is established.

APP issues

Innsbruck Approach has much less to do as Tower does the "director" job. Main things to get organized are:

  • arrange arriving traffic from the North and East in a nice stack in the RTT holding.
  • Enquire aircraft coming via BRENO if they want to appproach West or East.
  • Merge arriving aircraft from East and West so that they don't meet head-on at AB NDB

More precicely, you should take care about:

Airspace

... of LOWI_APP reaches up to FL165 (this is why departing aircraft are cleared FL160).

Airspaces around:

  • Above and North is EDDM-CTR. EDDM-APP is near, but not connected.
  • East is LOVV-CTR.
  • South is Padova Radar (LIPP_N_CTR 125.47) up to FL195. Near, but not connected, is Padova Upper Radar above FL195 (LIUP_CTR 132.90). Sometimes, Milano Radar (LIMN_N_CTR 127.45) is online and takes the whole north Italian airspace.
  • East (but not connected) is Swiss Radar (LSAS-CTR)

Arrival

The STARs tell the story: Aircraft meet at RTT NDB or KTI NDB. You can vector aircraft or clear STARs.

  • From the North, you get TULSI arrivals at FL150 over TULSI, released for descent to FL130 for RTT.
  • ALGOI arrivals are handed off at FL180, further released for descent to FL150 (they fly KTI).
  • From the West, aircraft arrive at FL180 or more towards KTI.

Caution: German controllers hand off differently: First they hand off. Second, you accept. Third, they tell the pilot. Fourth, the pilot contacts you. Sometimes, this ends up with the aircraft in sight of RTT.

  • Aircraft from the South arrive at BRENO with something like FL150. You can ask or order the pilot to fly BRENO2A or 2B arrival - don't expect all pilots to know the difference :-) You might as well issue a direct to RTT oder KTI.

Towards RTT, clear aircraft to MRVA, and then to descend 10.000ft (local QNH) to be levelled at RTT NDB. Don't forget that you may need to stack them in the holding, AND you need to leave FL110 open to get departing aircraft through -> see holding management.

Towards KTI, the formally correct procedure is to clear aircraft to FL130, let them descend in the holding to 11.500ft (local QNH) and then clear them LOC DME West approach. If they come from the north or northwest, you clear them for 13.000ft and when KTI is less than 10nm away, to 11.500ft and the localizer.

Holding

For East arrivals, stack aircraft in the RTT holding. If you have intense outbound traffic, make sure to leave FL110 empty to "shoot" departing aircraft through. In this case, alert Tower to clear departing aircraft to FL110 only. You have a holding over KTI, which you will rarely need.

There is a trouble at very high traffic: Aircraft arrive low, and the RTT holding is full with about 6 aircraft. If this occurs, then tell München Center to open a holding at TULSI and open another holding at NANIT. To the west, ELMEM is a good choice for a second holding.

Approach

Caution: Arrival procedures start at RTT and KTI, and there is no vectoring beyond these points. If the pilot asks for it, issue go-around and ask the pilot, if he has charts (and divert to EDDM or LOWS if he has not). No-one can land without knowing approach procedures.

For West arrivals, you have to distinguish:

  • From the West and Northwest, you can clear aircraft to 11.500 feed (QNH!) straight and clear LOC DME West.
  • From the South, aircraft would spoil their nose at that altitude. Either clear them to FL130 to KTI and to fly one turn in the holding to descend before clearing LOC DME West, or clear them to FL140 and BRENO2A arrival, after INN NDB FL120 and when nearing RTT NDB, 10.000ft.

Approach clearance is straightforward: 

Leipzig 123, cleared Localizer DME east approach, report established.
Leipzig 456, cleared Localizer DME west approach, report established.

To merge East and West traffic, measure the distance to AB NDB - separate them laterally with at least 6nm for landing with backtrack. If you happen to have aircraft closer, then alert Tower and see if he can clear the first aircraft rwy26 and the second rwy08 (and Tower won't be happy about that mess). In this case, Tower should clear descent of the LOC DME West approaching aircraft to 6.000 to separate horizontally over KTI NDB. Turn and downwind are far enough to descend the remaining 3500ft.

Special performance arrivals are cleared on request only and are much less hassle. RNAV West approach directly ends up in runway 08 - take care about different spacing!

Handover to tower is as soon as the pilot reports established. Beware of departure/arrival conflict situations: You should have both conflict situations on the same frequency - both APP or both Tower. Teamspeak is very handy for this.

Departures

Standard departures to the East all have similar patterns: You get them from Tower when conflict-free. As soon as the aircraft is clear of peaks (FL100) you can issue a direct to avoid conflict with holding aircraft over RTT.

Standard departures to the West are very easy: They (should) just fly out, not messing up anybody.

Handover

Strictly, all aircraft must be handed over to München Center, as the airspace above is his'. But most likely he won't want to have them all, when they fly out east, south or west. In the end, it comes to the following:

  • To Germany: hand over to EDDM-CTR.
  • To EDDM: München Approach is near and EDDM-CTR might want you to hand pilots directly to Appraoch. Ask him if online.
  • To the East: hand over to LOVV-CTR: München won't accept aircraft for a 1 minute transit.
  • To the South: the same: hand over to LIPP_N_CTR (125.470).
  • To the West: Normally, München Center will take them until Swiss Radar is in range.

Beware the German handover procedures: 1) handover in Euroscope 2) Accept by Controller, 3) handover to the pilot & bye. You can do that after the aircraft has passed RTT or received a direct.

Coordination APP-TWR

Coordination with TWR in Innsbruck is more important than on any other airport in Austria, because runway decision is tower (and might change on short notice), but has major consequences for arrival spacing. So you should do the following:

  • TWR needs to tell APP default arrival runway so that APP can adjust spacing.
  • APP needs to ask for exceptions (if pilots request the other runway and the like)
  • TWR needs to tell all exceptions (other than default departure runway, visual climbouts etc.)
  • It is a good idea that APP tells TWR if west approaches come in.

A good help is if the two stations listen to the other's radio (Euroscope: Listen to frequency, and hardware setup: output line 2 to a different speaker), then most coordination problems never occur.

Weather minima

At VATSIM, weather minima are sort of - virtual, by definition. However, we have METAR to have a guess on the weather out there and can follow these conditions.

For Innsbruck, there are no LVP (low visibility procedures) as such. There are minima which are relevant first to the pilot, second to Tower controller.

VFR flight

In real life, there are no special rules for VFR flight, therefore the minima for airspaces apply. Innsbruck CTR is B, and that means:

  • up to 10.000ft 5km, above that 8km flight visibility AND
  • free of clouds.

TWR can issue a warning at entry clearance that weather is below VMC, if METAR suggests that: 

LOWI_TWR: OE-LBN, weather information: flight visibility probably below VMC: visibility 4km, broken clouds with base at 3500ft.

IFR arrivals

  • Aircraft category A-B: 3km flight visibility
    For LOC DME East this means: At 1,6nm OEV DME you should see ground, slopes and the runway or go around.
    For LOC DME West this means: Overflying the airport, you should see the airport which is roughly 1,5km below you, and at AB DNB you should see ground and the right mountain slope, which is a good 2km away (if you don't see the slope, you can't turn without hitting it).
  • Aircraft category C-D: 5km flight visibility
    For LOC DME East this means: At about 3nm OEV DME you should see ground, slopes and the runway or go around.
    For LOC DME West this means: Overflying the airport, you should see the airport which is roughly 1,5km below you, and at AB DNB you should see ground and the right mountain slope, which is a good 2km away.

It is up to pilots to monitor conditions at landing!

IFR departures

  • Ground visibility: 1.500m AND
  • Ceiling: 1.500m
  • Exception 1: for Special Performance Departure: RVR 300m.
  • Exception 2: For departure from Rwy 08, if low fog, mist or snow blowing over the airport:
    RVR 600m AND
    visibility >5km above this layer AND
    no further clouds 3.100ft AAL

It is up to pilots to monitor conditions, but Tower may deny takeoff clearance if visibility is below minima according to METAR. Tower may offer the RNP 0.3 departure instead, or issue a warning 

LOWI_TWR: Speedbird xxx, ground visibility is 1.400m, that is below IMC, are you able for RNP 0.3 RNAV departure runway 26?
BAAxxx: Negative, Speedbird xxx, we continue with present clearance.
LOWI_TWR: Speedbird xxx, in this case: go ahead with present clearance, wind calm, runway 26 cleared for takeoff.

LOWI_TWR: Speedbird xxx, RVR 700m, ceiling at 4000ft, above that CAVOK, wind calm, rwy26 cleared for takeoff.
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