Wind correction in the hold

[Tinstaafl]

I've had to hold many times in Oz, UK & now that I'm working here, in the US. Holds *do* happen.

US holding procedures require the pilot to try to make good the hold timing on the **inbound** leg, not the outbound (+/- any HWC/TWC adjustment) as used by ICAO. In effect you need to time both outbound & inbound legs and attempt to adjust the outbound timing so that the inbound time is as close as practicable to the time specified for that holding procedure.

This isn't related to drift correction - just to achieving the specified hold timing on the inbound leg. Drift correction is something else again.

I'm not overly fond of the various X x the estimated drift on the outbound leg methods, although I've used them. Generally I approximate the drift correction by rounding to multiples of 5 or 10 deg deg to adjust my outbound heading. If I suspect the drift will be small then 5 or 10 deg is usually adequate. If medium then 10 or 15 deg, and if strong then maybe 20 deg.

If it's an NDB based hold then I also use the position of the needle for guidance about my position at the end of the outbound leg. For a 1 min hold the needle should be ~30 deg offset from 180 deg (+/- any heading correction). A 2 minute hold gives about 15-20 deg offset. If less than that then I know I've drifted/over adjusted for drift to the 'inside' of the hold & may need to compensate during the inbound intercept. If more than that then I've drifted/over adjusted to the 'outside' of the hold & will probably have to stop the turn at 90 or 45 deg to go. At 90 deg to the intercept the ADF should read ~10 deg ahead of the wing & at 45 deg to the intercept ~5 deg lead. This lets me judge how the intercept is going because I can choose to reduce or even stop the turn if the needle leads by too much or slightly increase the turn rate if it lags with a possible requirement to re-intercept from the other side of the inbound course.

A 2 min hold gives an opportunity for an *approximate* 'double the TE' type heading correction at the 1 min timing point (or half way if the timing is adjusted for HWC/TWC). However many degrees the RBI/RMI is reading above or below the expected 30 deg offset can be doubled to be come a heading correction to hold until the end of the two minutes eg at 1 min the RBI shows 35 deg instead of the expected 30 deg. so make a 10 deg HDG correction towards the holding pattern (towards because the greater reading puts the a/c outside the holding pattern. A 25 deg reading would put the a/c 'inside' the hold so you would then turn away from the hold). No need to be too wound up about it - a hold isn't a precision procedure, especially on the outbound leg.

A VOR can also be used similarly but it takes a bit of OBS twiddling to get the information.