The Arctic UAV mission

TECHNISERV is an international company with offices in Russia, Czech Republic, Slovakia and Poland, which provides the inspections services by using remote piloted vehicles (copters, planes, submarines). One of these inspections was arctic UAV mission.

Our team was involved in performing inspection of Flare system on Berkut rig using an UAV (Unmanned Aerial Vehicle). The scope of the inspection was to get clear information about current state of the Flare system, which is very important for integrity. During the inspection, the Flare system was being in normal operational mode, i.e. means the ladders and the flare structure were completely restricted to access by persons. Therefore, the UAV/Drone was the ideal way to get closer and have a clear view on complete structure of the Flare system. Our UAV was being able to fly around the Flare tower at different altitudes and got a detailed view on all parts of the complete Flare structure. Using the UAV for inspection means no risk for operating personnel because all of them were at the safe place, away from the flare flames and heat. Using a drone allowed to get the important information in very time-efficient way. We had provided the customer with the results of the inspection at the end of the day.

Berkut Rig is currently the world’s biggest oil and gas rig in operation. It is located in Okhotsk Sea, in the northeast part of the Russian Federation. The area is commonly known as an Arctic zone. Berkut rig is operated by American company – ExxonMobil.

The inspection was performed in February, which is the coldest month of the year. We got a chance to understand completely what does mean – The Arctic. The local weather conditions were behind the official drone operating conditions. Temperature was around -25 ºC, apparent temperature -30 ºC, wind speed around 12m/s, sunny day. The sea around the rig was covered by ice, and the rig deck offered very nice view.

Although we had experience with other rigs at this region, but with huge dimensions of the Berkut rig, came a range of challenges we had to solve. Magnetometer had problems caused by closeness of the huge metal construction, especially during take off and landing. Because the place of operation was at far north and high drilling tower construction interfering the satellites mostly located at equator area, GPS signal was also extremely poor. The only solution was to flight in manual mode. The cold weather had impact on all of the drone cables. They lost their elasticity in those conditions. Crusted cables caused loss of gimbal stabilization. The micro vibrations led via crusted cables to the IMU connectors and some of them were loosen at the end of inspection, even if we used the extra flexible cables.

Our team is equipped by the UAV manufactured by German company Microdrones, together with Sony NEX7 and Flir Tau640 cameras as useful load. This drone has external dimensions 1730mm x 1730mm. We selected the place for the take off based on these dimensions, but it could not be used, because it was occupied by containers and the rig spare parts. Safe take off and landing could be performed from heliport only. It was another operations challenge for us, because the heliport was located at the opposite side of the rig then the flare, at the distance of 200m. We had to keep the visual contact with the drone, so, we were coordinating our work with a crane operator. All the issues described above had made this inspection mission very challenging for us. As the result of the inspection, we had delivered to the customer the comprehensive report describing the actual state of the whole system. The Arctic mission was completed successfully and we gained a great amount of valuable experience.

More information on web thedroneinspection.com