Want Alpine thrills? Try competitive paper plane flying
World championship for bored kids
Competitors -- around 180 people from around the globe -- were able to travel ultra lightly to Salzburg with their "kit" composed of simple pieces of standard A4 size paper.
Not a classic tourist trip
But, for one weekend only, competitors will be out to see who can launch their "fighter aircraft" the furthest or loop the loop most spectacularly or else stay in the air the longest.
Competition mode on
Most participants say they came to the event, organised by Austrian firm Red Bull, just "by chance" or "for fun".
But once engaged, the competition has really drawn them in, organisers say.
"The level is impressive. Some participants can throw for 50 metres (160 feet)," French competitor Jonathan Miraucourt, 24, told AFP as he prepared to joust in the "long distance" category.
He said he was pondering even at this late stage whether to change his trusted technique of a small run-up designed to ensure a stable flight.
Participants have varying views on technique, from how to fold the paper just so in order to propel the "jets" skyward.
Art of paper folding
Ryan Naccarato, from Los Angeles, won the "acrobatic" category in 2012 and wears the calm mien of that successful experience as he prepares for his third event in a competition first held in 2006.
"You have to adapt to the parameters of each event: the quality of the paper, weight, air temperature, humidity," explains the 29-year-old, a big fan of origami.
That art of paper folding originated in Japan, which is where 54-year-old Emmei Shinichi -- the oldest competitor in a mainly male field -- comes from.
Counting down to the event, Shinichi was studiously putting the final touches to a complex model he hopes can remain airborne longer than anyone else's.
One Indonesian entry consisting of two pieces of paper flapping in concert was arousing early curiosity, as was an Indian man's concept of a paper boomerang that looked to be able to reach impressive speeds.
"For distance, we all make the same type of plane, in the form of a very fine arrow," explained an Algerian, flexing his arms and shoulders in warm-up exercises to ward off the potential onset of cramps at just the wrong moment.
All planes have to be made onsite in the organisers' Hangar7, home to historical planes and Formula One cars.
The venue has a view of the majestic Alps... as well as Salzburg airport's runways -- albeit too far away to have its airspace affected.