Closing Angle

[Vone Rotate]

Hi all,

Does anyone know how to work out the 'Closing Angle' for a PA-28 cruise speed of 100kts G/S?

I use this method but wondered how to adjust the closing angle to keep the times to 1nm=1min flying time. I currently use this:

E.g 1 mile off track = turn towards desired track 30deg for:
1 mins @ 120kts G/S
1 1/2 mins @ 90 kts G/S
2 mins @ 60kts G/S

I remember an FI examiner telling me you can work the angle out for your aircraft speed so its 1 min per mile off track to regain your desired track rather than adjust the time as I have done here.

Thanks