I figure like this:
3500 knots X 0.60 = 2100 mph
should be close.
Not close at all.
3,500 knot = 4,027.7 mile/hour (mph)
I get a different number.
3500 * (6076/5280) = 4027 mph
knots > miles > kilometers
Methinks you calculated for kilometers.
3500 kts. = 3500 x 1.15 = 4,025 mph!!!
kts. are knots, not kilometers
Backwards.
Knots figure should be lower than miles per hour.
What conversion handbook are you using? One knot equals 1.151 mph. 3500 knots would figure to 4,028.5 mph. your 0.60 conversion is closer to converting kilometers to miles.