Is there a set depth from the bottom the PA gliders will descend to? I think they use sonar to detect the bottom and then turn upward, but I can’t find anywhere what that distance is.
Yes the gliders use an altimeter to detect the bottom and inflect. It has likely varied over the years but at Pioneer we typically try to inflect between 10 and 20m above the bottom. There is usually some variance involved in this because the pump types differ in how long they take to inflect.
I wanted to follow up and let you know that the glider does record altitude data and it is available in the recovered files. If you were looking at the raw data files it would be parameter m_altitude.
This data is also available for recovered glider datasets ingested into OOINet under the glider_eng_recovered stream.