A Piece of Engineering !

by Vincent on April 27, 2008

I’m not sure of the reason why, but persons planning airports like to put them in challenging places. Look at this Google Earth view of Nice airport. Not only there’s always crosswinds because of sea-breeze, but there are hills in the axis and mountains on the north side.

Nice (LFMN) Airport Environment

There is no other option than having all departures and arrivals on the sea side, resulting in rather complex procedures. Typically, all departures include a right turn at 420 feet. This is easy in a light aircraft, but in a jet, this means a turn less than 30 seconds after departure.

The rest of the procedure is also a piece of engineering: multiple navaids, heading segments, radial change, and to make the whole thing worse, the navaids are not located on the airport. One of the turns must be done at 8DME from a certain beacon, which is located… at 8 DME from the airport. The procedure includes an initial turn followed by a leg which passes abeam the beacon. It’s only after passing the beacon, and being 8NM away that this turn at 8NM takes place.


If you have access to a Jeppesen, look at the LONSU and EPOLO departures. You can also download the official French AIP pages here.

Bern (LSZB) Airport Environment

Bern (LSZB) is also a good example of airport surrounded by significant hills. The initial departure includes a left turn at the end of runway to climb in a valley, then a left turn to a beacon located by the runway end. Another left turn is required after this very short homing to fly the outbound leg of the parallel entry to a holding. This holding is with right turns, with an inbound heading opposite to runway direction. Clear ? If not have a look at the FRI departures from RWY 14 (no free version available in Switzerland… sorry).

I don’t know if it is possible to design simpler procedures. In both cases the presence of cities that can’t be overflown in close vicinity makes the situation more complex. I don’t know who designed these procedures, but some require more engineering skills than flying skills.

For pilots used to clearances like “Maintain runway heading, climb to 8’000 feet”, flying a complex SID could create a serious overload. Not that I think there are pilots out there unable to fly them, but it requires a detailed briefing. The navigation setting must also be well thought and prepared.

Napoleon said that war is a simple art, of simple execution. This applies really well to instrument procedures. Be well prepared before opening the throttle, and you’ll be fine. No place for improvisation in instrument flying. Particularly when the pointy rocks are involved.

{ 2 comments… read them below or add one }

Cliff April 28, 2008 at 4:07 pm

The point is that these departures have been designed to be overlaid with the RNAV departures. In a suitably equipped plane, you just put, say, LONSO 3A into the GPS, get the autopilot on at takeoff and, other than initiating the right turn at 420 ft, it should do the rest.

Once everyone can (or is required to be able to) follow RNAV procedures, I’d expect LONSO 3E and similar to disappear.

As for Bern, there doesn’t appear to be a FRI departure. Has it been replaced. I have to say I’d far rather take the BER 1S departure over the low land than I would the MONIN 1S where I have to climb exactly as stated or risk hitting the mountain! BER 1S is the IFR equivalent of climbing in the overhead.

PlasticPilot April 28, 2008 at 6:42 pm

Cliff, you’re right, this is much easier with a GPS. But there are days where GPS fail (seldom, but does exist), and some procedures are not allowed as GPS overlay.

I flew both of them with GPS programmed but with no map nor coupling, just as backup (and unfortunately the Nice one in simulator). To be fair, I got lost in the Bern departure (while still in instruction). And in the case of Bern, no way asking for vectors, the lower airspace there has no radar coverage…

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