Valiant Tanker info required please
Am currently browsing a Valiant tanker pilot (deceased) log book to write up his flying career. Have reached 1958 entries and he is clearly on Tanker trials duties in which he notes during separate sorties: Trial 306: XD816: '2 below'; XD869: '3 below'; XD812: '2 above & 8 below'; XD816: '7 below'. For the month in question: June 1958 he totals: 'Hook-ups: 32 (12 above). I believe all these relate to 'dummy' tanker/receiver flights but it is not clear (to me) what is going on. Is there anyone out there who could interpret this for me please?