May 25, 2017

Glacier Benito Journal: Crossing the Glacier and the Mavic Takes Off – Friday 14th April

Posted by larryohanlon

See the other posts from this expedition here

By Martin Sessions

The plan on Friday was conduct Mavic drone flying from the middle of Level II on the glacier. So at 0945, all five of us set off to point ‘403’.

A brief pause in the walk to point ‘403’

On arrival Mark with Johnny and Marcos stayed at the point to fly some Mavic drone flights. Mark had the controls whilst Johnny reviewed the mission plan with directions, intent, primary and secondary objectives, planned heights, flyout bearing (worked out by Marcos), latitude and longuitude of waypoints and so on. Johnny provided subject matter expertise in the ‘observer’ role including points of interest to the science community (how the glacier stops flowing at the bottom of the Finger, and the need to have angle down photogoraphs to leave out the sky for mapping purposes, etc).

Mavic about to take off from point ‘403’

Mavic examining Dump Ridge where there might be a sledge from 1973

The first flight was to Dump Cairn area to see if the cairn or a sledge could be seen and to take a panorama in the vicinity. Continuing on that mission, the drone was then flown to the position of Stake 10 in 1972/73 for a further panorama. However at this stage the battery was running down so a photographic panorama was undertaken as the drone was returning to base which it does automatically once the battery starts getting flat! The second mission was to fly to the Level II Cairn at the Finger which was completed satisfactorily. A third flight was made down glacier from point ‘403’ towards ‘Not an Island’.

Goodbye Drone

The Drone Returns to the Red Panel Surveyed by Olaf earlier

Meanwhile Olaf and I continued across the glacier to the vicinity of Level II cairns on Dump Ridge. Progress became slower as we approached the ridge as the crevasses were getting wider and running at an inconvenient angle to the direction of travel. Eventually we made it to the edge of the glacier at 1400. Next problem was how to ascend the ridge because the rocky slope was steep and cluttered with unstable broken rock. Eventually we ascended to 790 m absl before deciding to call it a day because further ascent was too difficult. In fact the cairns, if they still exist, are further east of the former snow gulley. The high point was marked with GPS before we left the ridge to return to camp. On the way back, the Trimble GPS was running in rover mode to get a current profile of the glacier along Level II. We chose to follow the line of the crevasses for while going higher up the glacier before dropping down to take a direct line back to camp, arriving there at 1745.

Olaf and Martin Continue to Dump Ridge

Another Peak is revealed as we cross the glacier

The rock covered slope of Dump Ridge

Climbing Back down the ‘1972 Snow Gulley’

On the way back, we were buzzed by the Mavic!

The Mavic following Olaf and Martin

 — Next: Winding Up —

This post was originally published here

Martin Sessions was born in Kenya in 1948 but educated in England, finishing up with a degree in Engineering at Cambridge University (Pembroke College). For 28 years, he served in the Royal Navy as an Engineer Officer before migrating to Australia where he is an engineering consultant in Canberra. His first expedition was to Koldukvislarjokull in the North West corner of Vatnajokull, Iceland in 1970. Then followed expeditions to Chilean Patagonia (1972/73) and Liverpool Land, Greenland (1977). Finally he made expeditions to Glacier Benito in 2007, 2011 and 2017 to capitalize on work undertaken there in 1972/73.