φ is a Bank °
Turn Radius (r) in NM = TAS^2 / 68649 / tg φ °
Turn Radius (r) in sec=TAS / 19.07 / tg φ °
for calculatons on mobile phone calculator
Radius in NM for (φ 30°) = TAS*TAS /39683
(φ 15°) = TAS*TAS/ 18382
(φ 10°) = TAS*TAS/ 12107
for calculations from one's "top of head"
TAS 199 kt φ30 r=1 NM
φ16 r=2 NM
φ11 r=3 NM
Radius in SECONDS (φ 28°) ~ TAS / 10
(φ 15°) ~ TAS / 5
(φ 10°) ~3 xTAS /10
Turning Point= Radius (NM or KM) * tg (( next CRS – present CRS) /2)
