Measurement equipment is let down into the sea at the end of the Adventfjorden for testing. The sun is setting very slowly.

At the top of the plateau above the airport you can see the satellite domes. You can follow the ship through the Über marinetraffic site.

Adventfjorden is left behind and we go out to the sea through Isfjorden. The ship lulls us gently to sleep with pitch and roll movements.

We leave for the ship after an additional ice safety course at UNIS in the morning. A great piece of brand new technology, a bit confusing. The important information: There are three stairs, all ending on deck 5. The rear one goes up, the middle and front ones go down.

The facilities are very comfortable compared to some older research vessels. Our two-person cabin is at the front of the portside, the only one with only one porthole. There is a private shower, internet, desk and a flat screen with live ship data.

You are not just a passenger but part of the ship. Everything is full of marine technology, winches, cranes. Equipped with safety shoes and helmet, I carefully explore the ship, trying to locate our equipment on deck.

At noon, the pier is needed for another ship. Everything is moving, a slight little discomfort. The ship virtually drops anchor next to the German research icebreaker Maria S. Merian at Longyearbyen.

There is an introduction to the ship with a tour in the afternoon. Everybody crawls into the rescue sub. There is a short outline of the program of the next days. Then there is the safety exercise and dinner.

Our aircraft, net and sandbags have reached the helicopter hangar.

We very carefully get closer to the idea of flying our aircraft from here. The edge of the helideck is approached only cautios. It is spooky to look over the folding railing to the deep, dark sea.

The SUMO aircraft received fiberglass reinforcements around the wing tips and ABS plastic covers over the servo links. That should protect them during landings.

The object of desire arrived overnight at the coal port of Longyearbyen: The research icebreaker RV Kronprins Haakon. We will spend twelve days on it in the Arctic Sea. The LIDAR and Radiowave instruments are getting installed on the ship. In the evening we meet other participants of the measuring campaign at the Kroa.

Spitsbergen in early September, the island is not covered by snow. Structures, details and colors come to light everywhere. A completely different experience, so nice not to have to leave the house packed with clothes.

We prepare by hardening the aircraft and filling sandbags.

On last nights flight a faint white-greenish whiff of impossible-to-photograph polar lights showed up in the north-eastern sky when we passed Bodø. Around Bear Island they lost against the the midnight sun that was acting below the horizon. The southern tip of Spitsbergen was then clearly recognizable.

There will be a third measurement campaign this year. That required a one-day course in personal survival techniques. It was fun to jump of the quay wall in a survival suit and to crawl into a life raft.

There is still some light as we directly drive from UNIS to the other side of Adventdalen, across from Longyearbyen. Steam rises from the fjord.

The air near the ground (where we stand) is -20°C cold. It is ok as there is no breeze. The mini Talon is having fun at -12°C in 50m altitude. This has often been the case here in the valley: we are freezing and the plane is enjoying the warmer air further up.

The sky is great, full of stars. The LEDs of the mini Talons mark his path. Every now and then a touch of a polar light draws across the sky. Above the contours of the mountains to the south you can see a light green at the distance. We are too far north on Svalbard for strong polar lights today.

For the first time I am cold. Standing motionless in the cold can be unpleasant even with good equipment. The mini talon flies profiles over valley and fjord.

We warm up in the old polar light station after two flights. Then we head out for another profile to 1000m and stacked lines.

The program is different today: The airport is opened in the evening/night and we are allowed to fly in the morning.

The sun is not yet appearing over the mountains. The small amount of light gets reflected by the snow and wonderfully illuminates the valley. The horizon is filled with colors. A new flightplan is created with the students. The mini Talon flies different profiles from the old polar light station far into the valley. Air temperature is only -15°C but perfect to be in as there is almost no wind close to the ground.

The air gets warmer further up and there is a layer with stronger wind. The mini Talon flies at different heights on a line and perpendicularly through the valley.

Simultaneously another group of students follows the track with sensors on snowmobiles.

A great day.

We head out to the station in the afternoon to test a new plane: the mini Talon. It already did some test flights in Finland and should now show its capabilities in strong winds. It can fly faster (40m/s), allows a larger payload and is more efficient than the SUMO. For a flight at a constant altitude it needs about 50% less power. But it is much harder to fine tune and fly. The main application is to fly at high wind speeds and operate turbulence sensors that give a more accurately signal at higher speeds.

The advantage of the SUMO is that is possible to operate at up to 15m/s wind even with low model aircraft skills. The autopilot keeps the aircraft level in the assisted “Auto1” mode. The mini Talon needs more active flying by the pilot. The approach has to be precisely planned as it glides very well.

In contrast to yesterday there is strong wind with speeds up to 13m/s. The wind speed is lower at higher altitudes. We seek shelter in the lee of the Bandvagn at the beach. The plane can cope with the turbulent gusts in 40m altitude only after we have reduced the control gains of the autopilot. Profiles are flown at different places in the valley entrance.

The clouds disappear during the night. There is an interesting temperature drop at midnight. Icing on the plane should no longer be an issue. We drive to the old polar light station in the afternoon and fly a 500m and 1500m profile as a test. The Bandvagn brings us to the “beach” at Adventfjorden.

We are flying several profiles from the fjord to the valley as in February 2016 to measure the atmosphere in different parts of the valley.

We use Panasonic Toughbooks as ground station, mostly the CF-19. The computer really cares about its components. It does not charge too cold batteries and heats the hard drive before a boot with a built-in heating foil. This is no longer necessary with the SSDs that replaced the magnetic disks – but it can not be switched off.

The lithium polymer batteries are preheated to about 40°C with a camping cooler/heater. The entire SUMO is made of EPP (a soft polystyrene foam) and the battery compartment is sealed from airflow. During the flight the battery heats itself through the electrical current flowing through it.
The air inside the battery case of the bebop2met is sufficiently insulating. In addition, the powerful computer directly under the battery heats it.

Thin wool gloves with fleece fold-down finger tips above are being used to control the manual takeoffs and landings. Scooter suits are worn against the cold wind.

Chocolate plays an important role in heating from the inside. On special occasions and to match the weather it was “Kalter Hund” tonight.

The aircraft are checked and repaired in the morning. We exchange one engine that had behaved funny during the last campaign with the Polarstern. In the afternoon we use the Swedish-made “Bandvagn” vehicle to go out to the old Aurora station.

What a great device. You can go everywhere with it. But it is horribly loud and moves only slowly. The engine is mounted in between the front seats and makes everything vibrate.

The machine needs a lot of love. We carefully check the oil level of the Daimler engine before running it.

The shock at the old Aurora station: The workshop is gone. There is a darkened room in which tourists can watch polar light films instead. The beautiful workshop in which we spent so many nights staring at aircraft icons circling, just gone.

We move to the kitchen and make the SUMOs ready to fly. It is snowing slightly. Propeller and the wings leading edge freeze on 400m, surprisingly. Svalbard is very dry and we had seen icing only once in all the years, even when we flew in clouds. The ice is rougher and not as clear as during the flights over Finland.

The tethered balloon is set up. The profile is quite unspectacular as expected. On the way home there is a glimpse of polar light over the mountains behind Longyearbyen.