From the very first conversation with a European pilot to each ensuing one thereafter, I have been warned about the “Föhn.” The word is a fancy German equivalent to “Chinook,” which implies what is ultimately a simple witch’s brew of meteorological malfeasance: mountains and wind. While Europeans tend not to be as cowboyish about these subjects, the gist was to be careful, as the Föhn is a nasty beast that will devour me and my airplane.
The Pyrenees enter into the picture. With no such warnings, I plunged into the mountain range and got beat up on the first time, a sunny September day. I would then learn that the Pyrenees are a mountain wave factory, with its own Föhn. Surely, I had mastered the skill, because a Föhn is a Föhn, no matter where it happens? Oh, how little the foreigner knows! Pilots continued to warn me about the Alps Föhn, even though I was living in a factory of mountain turbulence.
The thing is, nobody gave me specific warnings about said Föhn, it was just that “it’s there” and it can’t be good. I appropriately decided to make my initial forays into the Alps with significant caution, leaving wind out of it. It did not help that there were three fatal crashes in the week of my first trip here in 2018, and there have been many since. While I read to the extent I can in depth about crashes to learn from them, the fact with most of them was some other issue was in play. Surely the Föhn didn’t cause a midair collision?
As I got a bit friskier in the later part of the 2018 trip, I found that I was bereft of deadly wind, even if I wanted to find it. Curious. The weather actually seems to be structurally good in the Alps for quite a number of days. Now fast forward to 2019, and I found a similar situation…. the wind seems not to blow so fiercely on nice days.
Bit by bit, I have been toying with more upper level wind, and have come to find that it differs little from comparable speeds when in other mountain ranges. Updrafts, downdrafts, rotors, and turbulence have the same effect on an aircraft. The secret sauce is in figuring out what invisible air is doing, navigating accordingly. I decided to translate Rockies and Pyrenees knowledge here, and it seems like it’s working well. In fact, the Alps feature something that the aforementioned ranges lack: low valleys and passes. On days with stiff upper level winds and soaring mountain wave clouds, Swiss pilots are regularly flying at the lower levels of the atmosphere, avoiding the worst of it.
I decided to catalog some of the change of seasons and meteorological exploits from the past month. It starts out with the first snow in early September.
Second week of September. First snowfall! West of Zermatt, looking southeast.
Southeast side of the Weisshorn (4505m / 14,780′). It has enjoyed morning sun, so snow is beginning to melt.
North side of Wildhorn (3248m / 10,656′) with Mt. Blanc sneering from behind. Sheer white areas to the left are a glacier.
A couple of days later, I discovered Switzerland’s illustrious network of webcams. There is one 5,000 feet above the house on the hill behind us, so I checked to see if the stratus layer had a top. The webcam was above it, so after 30 minutes of curvy mountain roads and a 20 min jog up a trail, I was above the clouds. Dent du Jaman (left) and Massif du Chablais (horizon right). I had left the webcam open on my computer and when I returned it showed what I thought was impossible: the entire Bernese Oberland, in the direction of the airport, was suddenly socked in overcast! In a matter of 20 minutes, the whole thing clouded over. I checked Gstaad Airport webcam, and other than a few holes, socked. I emailed a bunch of people and they basically said, “yeah, that can happen in the evening.” Note to self: carry more fuel. I would rather not return to base above a solid stratus deck.
Next flight: Simplon Pass, with Italy about 5 miles away. Now the south side of the Alps gets the cloud deck, whereas the north side is entirely clear, with no mysterious clouding over upon my return.
I know I whined for quite a while about the inversion in Spain. I take it back now! I never expected a glacier, mountains, and a glorious inversion. Still in Switzerland, with Italy as the farthest island in the sky.
Next flight. I needed to move the plane before the runway was closed for a bit. It was windier than I liked, though I could stay low if I wanted and avoid it. A high-time pilot seemed nonplussed (“There is no point flying backwards”), other than to indicate that “its usually rough over Martigny.” So I went there on the way to Mt. Blanc. Over the pass to France, I broke my record for the slowest groundspeed yet: 35kt with 39kt winds. It was smooth over the pass and upwind of terrain. Before someone gets too carried away with my apparent silliness, I got passed while in the pass (aircraft in the image below). There was a lot of air traffic for a windy day.
Mt. Blanc (4809m / 15,777′). Highest in the Alps. Note blowing snow below. Winds at 15,000′ were 50kt over Grenoble and 20kt over Turin. I came across another airplane and a helicopter here, all of us intelligently upwind. The wave was perfectly smooth, giving climb rates above 12,000 feet in excess of engine power at 4,000 feet.
Above the wave, sloped to the left above the Aiguille Verte (4122m / 13,524′). It was an illustrious flight.
I have now released book #19 “Mountain Texture: The Pyrenees from the Sky.”