I recalled a one-page article in Soaring magazine that promoted the
idea of using knots for vertical speed on the variometer. I finally
found it in the Soaring magazine index: June 1963. The author used a
pseudonym ("Sinbad"). I assume the soaring world was moving in that
direction anyway but this was the first our little group in the
midwest had heard of this idea. Within a few years, certainly by 1970,
everyone seemed to be switching over to knots both in conversation as
well as what they ordered on new instrument dials. It was a change for
me from feet per second (on a Cosim pellet vario--anyone remember
those?), meters per second (what the Winters of that era used), and
feet per minute (various varios of that day plus all of the light
aircraft rate-of-climbs we stuck into our glider panels as backups,
the most famous of which was the "Memphis" ROC that came out of Beech
Bonanzas from a decade or two earlier).

Chip Bearden
ASW 24 "JB"
USA