than most airfi elds with an instrument
approach. Pilots fi nd they are often in and
out of clouds at the decision height, and
they must be very familiar with the area
and the procedures in order to continue.
“The valley [is only wide enough to]
allow the 180o turn at a maximum of 150
or 160kts, and bank angles must be at
least 25o. The documented procedures
highlight these issues, which demand
every aircraft’s performance is used to its
maximum extent.
“There is a lower MDA of between 2,500ft
and 2,800ft above sea level (600-900ft
above the runway) available, but to use it
operators must prove that their aircraft are
able to climb above the obstacles with one
engine out and the anti-ice [systems] on.”
So how much does the weather impact
the regular comings and goings? “Those
procedures off ered a certain amount
of resilience, but they were still too high
on about 15% of winter days when there
were low clouds and snow,” said Wieser.
“Missed approaches turned towards the
next inbound. That led to complicated
separation issues for ATC to deal with
and there was no radar coverage below
9,000ft. The consequence was too
many diversions.”Improving the minima
The airport authority needed to improve
things, and in 2001 a procedure
was developed that enabled missed
approaches and departures to
continue westbound in the Upper Inn
Valley following the extended runway
centreline. This option was already
used for contingencies such as baulked
landings and fl ights in visual conditions.
Once the new approach was certifi ed,
it became available to aircraft carrying
a combination of RNAV and GNSS (area
navigation and global navigation satellite
system) equipment, and operating
in instrument conditions. Obstacle
clearances came down to only 0.6nm.
Wieser continued: “In 2004 our RNAV
AR (authorisation required) approach
and standard instrument departure
procedures were approved and published.
We were the fi rst airport worldwide to get
those. They require special equipment on
the aircraft, so they are only available with
permission from Austro Control.
“Parallel to that, a new surveillance
system was developed which was also
the fi rst approved for operational use.
It provides full multilateration [radar
equivalent] coverage in the Inn Valley witha one-second update rate, so our service
to assist pilots is now guaranteed.”
But the authorities didn’t stop there
and another improvement to the MDA
followed in 2013. It was achieved through
a combination of another technology,
LNAV (lateral navigation), with RNAV. This
enabled improvements to be made to fl ight
tracks along the Upper Inn and brought
the height at which pilots must either see
the runway or go around down to 350ft.
Again, using it needs special permission,
but nine airlines have obtained approval.Keeping things moving
Innsbruck describes itself as ‘Alpine-
urban, sporty, dynamic and cosmopolitan
yet charming, strong and traditional’.
Its airport is an important economic
driver in the region, the gateway to the
Austrian Alps, and is one of the city’s
largest employers. There is no doubt
the authorities have done all they can to
ensure the dramatic approaches and
departures, and inclement weather, inhibit
fl ights on as few occasions as possible.
The proven and robust ability to keep
people moving ensures the sights and ski
slopes are busy, no ma er whether the
skies are blue or overcast grey.ACKNOWLEDGEMENTS
The author would like to thank Armin
Sto er and Michael Wieser for their
assistance in compiling this feature.AIRLINES
Austrian Airlines
British Airways
Czech Airlines
easyJet
Eurowings
Finnair
Flybe
Laudamotion
SAS Scandinavian Airlines
S7 Airlines
Thomas Cook Airlines
Transavia
TUI Airways
TUI fl y BelgiumABOVE: British
and Scandinavian
charter jets line
the apron during
a busy winter
weekend. (Air-
TeamImages.com /
Dominic Spuller)BELOW: The Inn
Valley might seem
quite wide from
the cockpit of
a light aircra ,
but it is rather
tight for fast-
moving airliners.
(Ma hias Kunde
via Innsbruck
Airport)INNSBRUCK
Extreme Airports // 2116-21_Innsbruck.indd 21 11/05/2018 14:21