Hang on a second guys.
IO540's method works fine, and it involves much less mental arithmetic than Beagles.
Assess the cross wind component using the 1 in 6 rule.
Wind is 10 degrees off, then 1/6 of wind speed = cross wind.
20 degrees off, then 2/6 of wind speed = cross wind
.....
60 degrees off, then full wind speed = cross wind component.
Then if you're aircraft cruises at 100kt to 135kt take half of your cross wind, and adjust your heading by that.
17% out?
That's irrelevant! If it was 30% out it still wouldn't matter that much.
If your correction was a massive 15 degrees, and you were a massive 30% out, you'd be correcting by a massive 5 degrees in error!
Haven't we all, who have learnt dead reckoning, learnt to fly with the correct heading, identify a fix at our waypoint, and then adjust that heading to A) fix our track heading, and B) close back on to our track by the next waypoint?
The drift correction, is effectively only used between our first two waypoint. After that we should have adjusted our heading, by reference to the results of the first leg. So even the massive 5 degree error is not going to be too important.
dp