Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Alkor	AL559b	12.07.2021 - 14.07.2021	REEBUS MOSES	Baltic Sea Eckernfoerder Bucht Western Baltic Sea

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Sommer Stefan	Helmholtz Centre for Ocean Research Kiel (GEOMAR)	Kiel	Kiel

Ziel der Reise / Objectives of Cruise:

AL559b: Major aim of the short Alkor cruise AL559b (12.-14. July 2021) was to conduct an extended underwater test of the newly developed Deep-Sea Rover (DSR) Panta Rhei. The DSR Panta Rhei represents a six-wheeled benthic vehicle, which is specifically designed to carry out repeated benthic oxygen flux measurements inside flux chambers for prolonged time periods of up to one year. Beside the DSR Panta Rhei, further tests with regard to positioning and a homing algorithm were conducted of the crawler/lander system VIATOR and MANSIO. These tests were performed within the framework of the Helmholtz and BMBF funded projects ARCHES, MOSES and REEBUS. The tests took place in the working area A1 at the entrance of the Eckernforde Bay at the north-eastern slope of Mittelgrund in water depths of 18-19 m. The gently sloping terrain with different seafloor types offers ideal test conditions for benthic vehicles, encompassing sandy sediments in shallow depths, which with depth become progressively muddy. At the 12th of July, a team of six scientists from the Helmholtz Centre for Ocean Research Kiel, GEOMAR boarded RV Alkor in Kiel (eastshore pier) after successfully having passed the required Covid-tests and laboratories were established for the envisaged field tests. At around 08:00 (CEST) RV Alkor left Kiel harbor under good weather conditions and headed towards the working area Mittelgrund (A1). During the tests, technical difficulties with regard to the operating robotic software and energy supply of the MANSIO/ VIATOR system were encountered. In addition, the catamaran, which is towed behind the VIATOR enabling fast WLAN data transfer between the VIATOR and the ship, capsized as one of its hull was flooded with water. Unfortunately, also the long-term test of the DSR Panta Rhei failed presumably due to a defect wake up module. At the 14. July 2021 13:15 (CEST) we left the working are and headed towards Kiel east-shore harbor. After cleaning and unloading the equipment, the scientific crew left RV Alkor at around 15:15 (CEST). Despite encountering several technical failures, we hope that their solution will contribute to make these increasingly complex mobile sensor platforms more robust and reliable for future applications. Scientifically relevant data were not obtained during this cruise.

Messungen / Measurements