AMSTERDAM AIRPORT SCHIPHOL / 12 DECEMBER 2014
LOSS OF SEPARATION
The primary responsibility of Air
Traffic Control the Netherlands is
ensuring the separation of aircraft
from other aircraft and ground
vehicles. All safety events that occur
at Air Traffic Control the Netherlands
are reported and investigated with
the objective to learn and improve,
and thus reduce the probability of
similar incidents in the future.
Piper P46T
Direct MISGO,
climb to FL060
FL037
Investigation follow-up
The owners of the small aircraft P46T
will pay more attention to the
adjustment of the altimeter during
annual ‘prof checks’.
Maintain FL060!
Maintain FL060!
FL060
FL065
Descent
immediately
FL067
Leiden
N
N
W
W
Den Haag
O
O
Hoek van Holland
Z
Z
1
2
Rotterdam The Hague Airport
Rotterdam
Hellevoetssluis
In the morning of Friday, December 12th
2014, two aircraft came closer than the
separation minimum in the approach
area for Amsterdam Airport Schiphol.
A small aircraft, Piper (P46T), departing
from Rotterdam The Hague Airport flew
higher than instructed by air traffic
control, causing a loss of separation
with a Dassault Falcon 900 (F900),
which was approaching Amsterdam
Airport Schiphol. As a result, the
horizontal separation between P46T
and F900 was reduced to 1,6 NM and
the vertical distance to 300ft. LVNL has
reported this occurrence to the Dutch
Safety Board and conducted its own
investigation.
Approaching
FL060. Maintain
3
4
3
4
5
5
Gouda
2
separation distance
1
FL070
Dassault Falcon 900
Flight Levels
A flight level (FL) is specific barometric
pressure, expressed as a nominal altitude
in hundreds of feet. The pressure is
computed assuming an International
standard sea-level pressure datum of
1013.25 hPa, and therefore is not
necessarily the same as the aircraft's true
altitude either above mean sea level or
above ground level.
Flight Levels are used to separate aircraft
above the height where ground obstacles
(like mountains) are no longer of concern.
FL070
Left heading Climb to
340
FL080
FL (1013.25 hPa)
Altitude referenced
to standard pressure
at sea level
One of the altimeters in the P46T was not
adjusted to standard pressure of 1013.25hPa.
As a result, this altimeter indicated that the
small aircraft was at 6000 ft (992hPa), which
actually is FL066 at 1013.25hPa.
FL
080
QNH
FL070
070
Transition Level (TL)
Transition Layer (TRL)
060
QNH060 = FL066
300ft
QNH (992 hPa)
Altitude referenced to
regional air pressure
060
1000ft
050
050
030
020
080
070
040
040
Transition Altitude (TA)
FL060
in combination with
upward turbulence
desired
altitude
030
020
010
010
000
000
Altitude referenced to
standard pressure at sea level
altitude referenced
to regional air pressure
Luchtverkeersleiding Nederland / Stationsplein Zuid-West 1001 / P.O.Box 75200 / 1117 ZT Schiphol / phone +31 (0)20 40 62 000 / [email protected]