Flying across Germany to the Alps

JoakimHermansson wrote:

And, when I get to the alps, my plan is to follow the A56 Gafor route from Salzburg to LOWZ. I’ve never used Gafor routes before, and I can’t find much useful information anywhere about how they actually work. I wonder, can I enter a route anywhere, or do I have to join the route at certain points? At what altitude should I fly? In skydemon I can see what the reference altitude is, what does that mean?

Swiss and Austrian GAFOR routes are routes that go through valleys, with the intention of allowing you to fly below the level of the mountain peaks. You don’t have to follow them, you don’t have to enter or exit them at specific points, but they are designed to be convenient for lower level flying, and to provide a documented “path” through valleys that gets you from point A to point B while encountering, among the possible ways, the lowest maximum terrain altitude.

The reference altitude is the highest terrain along the route, along a very narrow corridor (if I recall correctly in Austria, that is a 3nmi corridor? I think Switzerland is different.). That is terrain, not obstacles. Not cables slung across valleys. You should fly higher than that. 500ft above that is not legally enough, because you must be 500ft above obstacles. IMO make it more than the legal minimum. IMO, the higher you fly, the better; but don’t get yourself in hypoxia.

If you don’t have experience in flying in the mountains, please consider several points:

• If you turn into the wrong valley, you may encounter higher terrain than planned. The “wrong” valley may be narrow and/or a dead-end (considering your plane’s climbing ability, both as maximum level and angle of climb… maybe with tailwind), making a U-turn mandatory but difficult to impossible.
• In a valley, GPS reception will be less good than otherwise. Will you be able to use GPS and Skydemon to not turn to the wrong valley?
• You should fly on the right side of the valley, both as a kind of avoiding head-on collisions and as a way to give you more space for a U-turn.
• You should not fly too close to the mountain slopes, because katabatic wind can be faster than your plane’s climbing ability. And if the cloud base is above mountain tops, the anabatic wind may blow you up right into cloud.
• Approach a saddle point (mountain pass) and ridges at a 45° angle, will make a turn away from it a 90° turn instead of 180°.

If the weather allows it and your plane can fly high enough that you don’t have to follow valleys (and GAFOR routes), then it may be safer to fly higher; if you climb enough to be above most peaks, even if you have to avoid the highest peaks, navigation is easier (and more direct / shorter) and consequences of errors of navigation less dramatic. But don’t get yourself in hypoxia.

Mountain flying is very fun, and gives magnificent views. I don’t mean to tell you you shouldn’t do it. Just, please get educated on how to do it.

JoakimHermansson wrote:

Is it Bremen Information that grants clearance to cross Berlin CTA? Does anyone know if there’s a good chance I’ll be given a clearance or is it more likely that I will have to fly around Berlin?

Bremen Information will give you information service only, such as frequencys or metars etc. Nearly all VFR-flights do cross Berlin inside Airspace D at max. 2500 feet, there are some VFR transit routes you should know beforehand. If weather and traffic permits there is a good chance to get a clearance from Tegel-Tower in the north of Berlin or from Schönefeld-Tower in the south. For crossing Berlin inside Airspace C on a VFR Flight it is very difficult to get a clearance from Radar, you need to ask Berlin-Arrival or Departure. In my experiance it is easier to plan the flight around Berlin on a VFR-Flight.

JoakimHermansson wrote:

And, when I get to the alps, my plan is to follow the A56 Gafor route from Salzburg to LOWZ. I’ve never used Gafor routes before, and I can’t find much useful information anywhere about how they actually work. I wonder, can I enter a route anywhere, or do I have to join the route at certain points? At what altitude should I fly? In skydemon I can see what the reference altitude is, what does that mean?

GAFOR-routes are basically the usual trails flown by pilots, and weather information are provided for these routes. They are no mandatory routes nor do you need to join at specific points. You use them, in full or partially, or not. The reference altitude is the altitude where the forecasts are based on. For example, pilots typically fly at reference altitude +1000ft. So frankly said you could consider the reference altitude as “ground” (but don´t forget the obstacles!).

Maybe helpful for flight planning / preparation:
Austrian AIP: https://eaip.austrocontrol.at/
ICAO map: https://www.austrocontrol.at/pilots/pre-flight_preparation/aim_products/aeronautical_chart_-_icao_1500_000

Have fun!

Sounds like a nice flight. Not much to add to the excellent advice above.
The GAFOR routes correspond to the „General Aviation Forecast“ GAMET (since 2016 called low level sig wx alps), a special met report.
The GAFOR is published and amended daily for these routes, entailing if the route is clear, marginal or closed. You fly them when for performance or wx reasons you can’t fly a direct routing, or if you want to :)

Following valleys without local topographical knowledge by flying a route on the gps is possible but be aware even short heads down moments can cause you to come very close to other traffic, terrain, material cablecars, obstacles, powerlines etc.. and (like Peter said) if for any reason you enter the wrong valley and you do not turn around early enough you will be in front of a mountain. Depends on the valley of course.
Also Wien Info can not give traffic info as there is no radar.
If you can, fly the GAFOR routes but „above“ instead of in the valleys. Some are easier, wider etc.. in reality than on the chart, others vice versa.