The expedition of all the surprises
A season under the sign of adversity from both natural and meteorological phenomena, aggravated by the lack of collaboration by some air traffic controllers and the increasing appetite of the customs officers in the port of Buenos Aires.
The first natural, and certainly the most meaningful, phenomenon was the eruption of the Chilean volcano Puyehue-Cordon del Caulle, situated 100 km NW of Bariloche, last June 4th, 2011. Photos, taken about 30 km away from the crater, give an idea of the size of the cataclysm. The immediate consequence for Bariloche was a solid rain that covered the city and the lake with 12 inches of sand and pumice stone, because, unfortunately, that day the wind was blowing right on the axis of the volcano (310°). After nearly 4000 people had been evacuated, normal life stopped completely for several weeks along hundreds of kilometres towards the East, the majority of the wild life died and thousands of bovines and sheep had to be euthanized because they were deprived of food and unable to eat the fodder that the farmers brought to them, because, never having seen it before, they did not know what it was!
Some days after the explosion, the volcano started spitting very fine, impalpable ashes (as light as icing sugar) sowing this thick, deadly powder along its plume that turned according to the will of the wind and falling to earth along a cone of 90° angle having its bisector oriented precisely W-E and whose edges were, unfortunately, the airports of Bariloche and San Martin de Los Andes, with, as a consequence, the inactivity of one or the other, and the impossibility of flying below 3000m along the 100km that separates these two airports.
Plume and affected area, 29.1.2012
Bariloche main street (Mitre)
The city of Bariloche remained paralyzed for more than a week, the time for the shovels to clean the streets. The hangar stayed safe, on the one hand because of its shape and, on the other, thanks to the fast intervention of club members while taking big risks.
Gliders hangar cleaning
The runway remained unusable for four months, the time for rain and snow to make the dust penetrate the soil and for the wind to displace the rest eastward up to Buenos Aires (1600 km), where the airports had to for close several days, like those of South Africa, Australia and New Zealand. Bariloche’s international airport remained closed from June 4th and only officially reopened on December 20th, while taking advantage of this forced stop to change the asphalt of the runway and add a water cleaning system in order to wash away the ashes deposited on the asphalt. In fact, commercial flights would only recommence at the end of January, and again with numerous interruptions each time the plume passed above the city. For the record, an airline jet remained trapped for several months on the tarmac. The pilot had received clearance to take off but the
This liner stayed there for months
controller did not realize that the cloud that was arriving over the city and the lake was, actually, a cloud of sand and ashes, which invested the plane during the initial roll out, obliging the pilot to abort the takeoff. The controller had not been informed about the eruption of the volcano!
From the point of view of the ground handling around the parking and club runway, the situation was not brilliant because the whole area of the gliding club was completely protected from the wind, preventing it from blowing the five inches of ashes away toward Buenos Aires! It was, therefore, necessary to live under these hard conditions, the feet in the ashes and, often, wearing a face mask, forced to go straight under the shower every day when back home.
Under the ashes, waiting for better times
Of course, you will say “But why the hell did you go there, knowing the situation? “ After long reflection, and consultations with the German team, we decided to go based upon the facts that, on the one hand, no eruption of the neighbouring volcanoes (Llaima and Chaiten in 2008) had lasted more than three months and, on the other hand, the area of influence of the plume had completely spared the neighbouring airports of (B) El Maiten (100 km south), (C) Esquel (200 km south), (D) Zapala (250 km north) so we could have moved the camp there if necessary. Actually, none of the plans B, C or D could be applied. For (A), the runway of El Maiten was too soft to allow the Nimbus to take off with two pilots, which forced me to abandon my passenger on the ground to return by bus, in his flight suit designed for -30°C but with +25° on the ground and not a single penny in his pocket! For (B), Esquel turned out to be practically QGO because the local ATC suddenly passed from one airplane per week to four per day (partially replacing Bariloche), so big panic! To the point that the Swiss, Jean-Marc Perrin (DG 800) and the U.S. Perlan Project team (DG 1000) had to abandon this solution after a few days because they had to take off before the airport opened and land after it closed, while prohibited from flying in half of the TMA, the good one, where the wave stays. The plan (D), moving to Zapala, could never be applied because of the abnormally South position of the Pacific anticyclone, so that the meteorological conditions were never favourable for more than one day at this latitude, thus eliminating any interest for a move that would mean losing two days and a lot of money. On the contrary, it would have been wiser to move the camp at least 300 km south, which proved impossible because of the absence of infrastructures and logistics compatible with the transportation of one container and the operating contingencies of the Nimbus 4DM, unable to taxi with it’s sole engine. Jean-Marc Perrin, coming from Switzerland with his own car, trailer and the DG 800 in 15 m, could therefore take advantage of these precarious runways and thus log flights between1500 and 2000 km, thus allowing him to win the OLC 2011.
Gliding and volcanic ash
The plume with clear sky, January 2012
To all things misfortune is good, it is said. If ash is actually a poison for the engines and prevents all take-offs, the situation changes when the motor is put back.
Once in flight, we discovered two types of volcanic ash:
Primary ash, which is the fresh ash leaving the crater and materialized in the plume, isolated and easily visible in a clear sky (January 2012) but hard to identify when absorbed into a cloud layer. Its extent perpendicular to the axis of the plume is quite limited, about 10 km at a distance of 100 km away from the volcano, but its density and toxicity are very high. Better to stay home, wearing the mask if required to go out.
Primary ashes embedded in the cloud layer, November 2011
In flight at 14.500ft above the erupting crater
The photo shows the position of the plume of primary ash on January 29, 2012. When the wind turns quickly, the ash front penetrates into the air mass like a cold front.
Front of ashes arriving from NW
Luckily, we have never been forced to fly under these conditions where the visibility is only a few tens of meters. The secondary ash is the consequence of wind erosion and lifting of the primary ash deposited onto the ground by the plume, carried away toward the East, day after day. The photo shows the extent of the damaged zone, a triangle whose leg is more than 600 km long.
Plume and affected area, 29.1.2012
The photo shows, on the one, hand the total desertification of the territory (we are flying abeam Caleufu, the wing pointing east, the territory visible on the photo is about 80 x 80 km), and, on the other hand, the intensification of the density of ash in suspension while going eastward.
Rio Caleufu covered with ashes
The photo, taken 50 km north of Bariloche at 6700 m, looking south towards the lake and the city, shows the position of the wind erosion ash front, the mountains located to the west appearing clean whereas, everything that is downwind of the front is totally unflyable, at least with an engine.
Wind ashes in movement
We had twice been forced to fly down home while crossing the secondary ash cloud. The top of this cloud doesn't exceed 3000m and the visibility is around a few hundred meters, in all directions. Considering the absence of icing risk, the presence of three redundant GPS navigation systems and of two gyroscopes supplied by three independent electric circuits, the IMC descent didn't pose any problem except that the time it took to come down from 3000m in this mash seemed to me an eternity that will not quickly fade from my memory.
But not everything has to be thrown away: the ashes lifted by the wind are so light, that they gorgeously materialized the hydraulic jumps and the classic rebounds. Very useful at the start, allowing us to easily identify the heart of the lift! The photo, taken at 3000m and 10km north of the airfield looking north, shows the perfect materialization of a small hydraulic jump, with the presence of Kelvin Helmholtz rolls while the particles of air and ash were falling at a super critical speed, which means a speed higher than the average speed of the surrounding air mass, consisting in a practically vertical rise of the particles from the ground until the altitude at which the speed becomes, once again, equal to that of the surrounding air mass, in the present case, around 3500m. One can observe that, about 50 km north, this system gives way to a classic, sinusoidal, rebound wave system without Kelvin Helmholtz rolls.
Hydraulic jump materialized by the ashes
The photo, looking eastward, shows the materialization of the lifted ash trapped in a magnificent hydraulic jump located downwind, right in the middle of the Pampa about 50 km away from the mountains. This photo shows three important features of the hydraulic jump: 1) the presence of rolls aligned with the axis of the wind ending precisely at the front, 2) a unique, practically vertical front, in which the particles of air and ash rise to the altitude of the laminar layer and 3) a high altitude cloud having a leading edge located headwind (into wind??) with respect to the ground line of the front (the shadow can be seen). In this case also, it can be observed that the ash does not pass into the laminar layer and remains caught between the ground and about 3000m. A disaster for power planes, light or commercial aviation.
Hydraulic jump materialized on the pampa
The photo, taken at 5000m and 50km North of the airfield, looking Northeast, shows, on one hand, the total absence of exchange between the two air masses and, on the other hand, the vertical amplitude of the sinusoidal displacement of an elementary particle, which is in the order of only 200 to 300 m. This characteristic represents the fundamental difference between thermal and wave lift. In the first case, each elementary particle travels the whole distance from the ground to the cloud, while, in the second case, it travels vertically only a few hundred meters and the movement is transmitted from one particle to another, similarly to the game of colliding pendula. It is therefore necessary to forget the classic diagram that can be found in the best books, in which one sees a sinusoidal movement of the fluid lines having an amplitude of the same order of magnitude as that of the mountain, whereas, the actual slant of the ascending and downward fluid lines is only a few degrees, hardly visible on a drawing at scale 1/1.
Materialization of the rebounds by the ashes
In conclusion, whatever the wave mode, no air particle is transferred from the turbulent layer to the laminar layer, which was always completely devoid of the least dust.
A capricious meteo
We therefore made “bad luck, good heart” (the best of a bad job), the ash was not the main thing that spoiled the season, the weather conditions did. Indeed, the direction of the "bad" wind, the one that made the plume pass above our heads, was about 310°, orientation far too North to give good waves because the subtropical air masses are too warm and humid and, in general, anticyclonic, and it is well known that it is not so much the speed of the wind that defines the intensity of a wave system, but more its temperature, its temperature gradient and its density (so, the colder, more stable and drier, the more powerful the wave).
Then, when the wind direction turned below 280°, we recovered with great pleasure the legendary purity of the Patagonian air and its fabulous waves, to a degree where, taken by the rage to fly at any cost and considering the particular conditions we were facing, we learned to fly with South wind, therefore parallel to the main line of the Andes, the technique being, in fact, the same we apply in the Alps, flying up and down from rebound to rebound, from peak to peak (positive wave), from lake to lake (negative wave) with the only difference that we had no landable field within a radius of 100 km, so “bye bye, high speeds”! But flying deep inside the Andes offers an unforgettable spectacle that replaces with great pleasure any speed or distance records. The figure shows the situation on January 11th, where the wind at altitude blew 30 to 40 kt full south, while it was, as usual, 20kt/300° on the ground. A rare situation but no less interesting.
Nefo of 11/01/12
These anomalies of pressure and temperature have been reported in fig. 20 where we see the temperature at 6000m parallel with the QNH at the take-off time. The first observation is that the temperature has always been above the standard (-24°C). The average is even 10°C above the standard and it is my opinion that this is the most meaningful phenomenon, since, ten years ago, it was around the standard. A warm up of 10°C in altitude is a real atmospheric cataclysm, whose consequences are completely unknown and unpredictable, this phenomenon being apparently ignored by the meteorologists and climatologists who keep their eyes on their thermometers on the ground or on the remaining polar ice! One more reason, in my humble opinion, for reducing the impact of human activities on global warming and an interesting subject for a debate about "environmentalism" and anthropo-centrism!" A glance on the curve of the QNH corroborates the moving down of the anticyclone 1000km southbound, or isn’t it rather the opposite? One could also say, that the temperature increase might only be the consequence of the pressure centres shifting. Messrs meteorologists, you have the chair, I remain at your disposal to start the debate.
Evolution of the temperature at 20,000ft and the QNH at takeoff
Consequently, the gliding activity has been the lowest of these last ten years with only 160 hours and 30 flying days out of 65 available days. The situation deteriorated continuously from mid-November, with periods of up to nine consecutive non-flyable days in December, essentially for lack of wind due to the positions and the strength of the anticyclones. The few thermal days were hard to fly because of the ash, which was put back in circulation by the convection. And since the two nearest emergency strips to the north and south (respectively 80 km and 100 km) were unusable for take off, no one wanted to take the risk of derigging the Nimbus in the ash!
The figureshows the situation of December 30 after seven days without a breath of wind, on the other hand very nice for swimming in a mirror lake. The Pacific high pressure centre is simply 1.000 km too South and the one on the Atlantic took the place of the usual low-pressure centre, that is the engine of the system, the one that "pulls" the flow and keeps the jet-streams blowing. The situation in the southern Patagonia was locally very good between 500 km and 1.000 km South from Bariloche, hopeless for us, but so good for Jean-Marc.
Nefo of 30/12/11
The Via Crucis of the customs
Looking for some place to put down the wings
Storage of the wings under the flying containers
Considering the very low number of European gliders (only four), we agreed to send only one container using that of the Germans, whose coordinator was Diether Memmert. At the beginning, I underestimated the cost of two out and return trips from southern to Osnabrück (near Hamburg) with trailer, i.e. 5000 km and eight travelling days. Diether’s clearance procedure appeared to be less efficient than mine and it was necessary to dispense €3000 in tips at all levels of the bureaucracy just to be able to leave the port within a reasonable time, days rather than weeks! The return was no less delirious: at the end of two weeks of endless discussions between our agent and the customs, while Diether had already returned to Germany, the “narcos” required us, without any possibility of negotiation, to fully empty the container setting all pieces on the ground, in the port. A total catastrophe. Diether and I had to return to Buenos Aires, hire some dockers and organize the removal of four fuselages, fourteen wings and about fifty bags and cases, to be laid on melting asphalt under the sun of a torrid summer, slaloming with our wings between mad trucks as we did our best to urgently leave this hell, and praying God that the containers that passed continuously over our heads remained firmly hung. A Kafkaesque delirium that cost us more than another €4000, just for allowing an unhappy dog to put her nose on absolutely all the pieces
The dog will sniff them all
. And to reach the peak of absurdity, they required us to check the container through the scanner after the control by the dogs. The decision is taken: never this any more! We are therefore working in search of alternative solutions, while hoping that the World Gliding Championship in Argentina next January can bring some improvement to the customs situation.
