O n this sunny spring day, two passengers board the unusually yellow and purple painted propeller plane.

It is located at the small Langenthal-Bleienbach airfield near the Swiss capital of Bern.

The two pilots have completed a thorough pre-flight check.

Now the engine is started.

The boxer engine starts immediately.

After warming up, the crew goes through the before takeoff checklist at the end of the taxiway.

Then the machine rolls onto the runway.

The captain goes full throttle.

After a short taxi ride, it's off to the sky.

So far, so normal.

Somehow this Pilatus PC-6 Porter is different from all the others.

The Swiss multi-purpose aircraft actually has a characteristically long fuselage nose.

It usually contains the powerful propeller turbine with 650 hp.

This example, on the other hand, looks short and cute.

No wonder.

The Porter was built in 1962 and is therefore an early example of the model series, at that time still with a piston engine.

The special thing about it is that it is a true-to-life replica of a PC-6 that first became famous in the Himalayas and then crashed there.

On January 14 of this year she had her second maiden flight after several years of restoration.

And now she's a precious one-off, the last piston-engined Porter in the world to fly.

To understand the meaning of this special machine, you have to look back 62 years.

Swiss mountaineers want to attempt the first ascent of the 8,167 meter high Dhaulagiri in Nepal in 1960.

It is the sixth highest mountain in the world.

That is why those responsible for the expedition to the Himalayas conclude a rental agreement with the aircraft manufacturer Pilatus Aircraft.

The then brand-new PC-6 prototype is equipped with a Lycoming piston engine and is intended to fly mountaineering material to the base camp.

With large Himalayan lettering on the hull and christened Yeti, this porter started on March 12, 1960 in Zurich.

The two pilots' journey to Nepal takes eight days.

The machine has a combined wheel and ski runner chassis so that it can take off and land on both snow and gravel roads.

First flights to get used to the high mountains follow.

Supply operations will start at the end of March.

The strikingly painted Porter flies with material or mountaineers to base camp 2 at an altitude of up to 5750 meters.

The pilots thereby set a world record for the highest landing of an airplane, which is still valid today.

Damaged beyond repair

It's not without risk.

Just weeks later, on May 5th, the crew lost their flying luck.

The Yeti crashes in thin air immediately after launch.

The reasons are unclear.

However, the six-cylinder with a nominal 340 hp has a significantly reduced performance at this enormous altitude.

Both pilots survive the crash unscathed.

The aircraft is irreparably damaged and cannot be transported away.

That is why parts of the wreck can still be found at the site of the accident today.