On Thursday, 6 May 2021 at 18:54:14 UTC+3, jfitch wrote:
The paper is fairly circumspect on the details of what they are doing. Their claim that this hasn't been done before seems disingenuous, given that the Air Vario had been out for a number of years producing (or claiming to produce) a similar result. Air's efforts are described in a university published paper from some years ago.

Yes, they are ignoring basically everything that has been done with variometer tech during last 25 years.