Menu Sign In Contact FAQ
Banner
Welcome to our forums

Wind correction angle advice

As a side question: How often do people fly holds when touring IFR in the Eurocontrol system?
I did only one in the last six months. It was in the UK when flying a procedural NDB approach.

I can recall maybe 2 ATC-assigned (i.e. not training) holds in total since 2005. One was at Zurich.

Administrator
Shoreham EGKA, United Kingdom

How often do people fly holds when touring IFR in the Eurocontrol system?

Once per year I would say (or every 300-350 hours flown). There are some places where you are (almost) always instructed to enter the hold like Madrid Barajas. Or Frankfurt at certain times of day. In winter it is quite common to have to hold for snow removal (20 minutes was my longest holding).

Last Edited by what_next at 20 Nov 14:56
EDDS - Stuttgart

Quote Therefore my feeling is that one should be able to fly a hold using the full RNAV display available, which would mean following the magenta line.

Without airdata input and heading input to the GPS, the magenta holding pattern shown on a WAAS GPS doesn’t correct for winds. In strong crosswind conditions, it can be very difficult to follow the depicted pattern and at the completion of the turn to the inbound leg, one may be quite far from alignment with the course. I teach to use as much as three times the inbound correction on the outbound DR leg, especially for a one minute hold. There are four legs of the hold, each of which is affected by the wind. The inbound leg is the only one that provides navigation, the other three are DR legs, two involving turns and one proceeding outbound. The times in all three DR legs as a first approximation are the same when a crosswind is involved, one minute, so the total drift is for the three legs, but correction for drift only occurs on the outbound leg. It is for this reason that I use the times 3 multiplier, particularly for slower aircraft where a crosswind has a greater relative effect.

On the Garmin WAAS GPS units, if airdata and heading is available, then the pattern is depicted with a wind corrected track and can be quite distorted in comparison to the oval shape. The objective of the distortion is to complete the turn to the inbound leg rolling out on the inbound track. An autopilot that either integrates or has an external roll steering adapter can fly these holds seamlessly.

KUZA, United States

In the US, pilots are required to treat the time or the distance as a maximum and can fly the hold with a time or distance less than the charted value, but not greater. If the hold is a timed hold, we can’t use distance other than as an aid to making the inbound time be as specified or less. So if the hold is a one minute hold and airspeed is 120 Kts, going outbound 4 NM would be outside the specification of one minute.

KUZA, United States

I do 3 x wca on the outbound leg, up to 30 degrees I think is the suggestion. On the inbound leg I do 1 x wca.

To be honest every time I have done holds in training, the winds aloft is rarely the same at the time of the hold and I wont deny I find the correction difficult. Ideally when you intercept the inbound track, you work out whether you over or under corrected and compensate accordingly next time round, or when descending outbound for the procedure. A GPS in real life makes it much much easier than a basic ADF. There might be some more info on this thread

Thanks all, I must admit, my aircraft doesn’t quite have the amount of kit the majority of you are giving me advice on but it’s an interesting read!
I think the best true way for me, pre exam, would be for me to work out WCA joining the hold ( as that’s not assessed) and then use the 3x WCA method on outbound leg.
Hopefully after I pass, I can work up my own technique using the ‘non certified’ equipment that I have at my disposal and fly in ‘the real world’!

Goodwood

and then use the 3x WCA method on outbound leg.

Don’t you mean the WCA is 3 x Drift?

Don’t you mean the WCA is 3 x Drift?

Yes sorry, I did mean that. I was rushing to go home from work when I typed that. Thanks.

If you have a GPS on board, it gives you track, the difference between track and heading = drift. GPS also gives you groundspeed. The difference between TAS and Groundspeed = wind component. I am amazed at how many pilots I have seen struggle to guess, and use out of date met information, to work this out when its all in front of them!

You apply 3 times the drift outbound so that you should finish up on the inbound radial, if you don’t, you can compensate for the single drift inbound based on where you finished up. Much better to eyeball it than work out loads of figures on the ground with rather dubious out of date forecasts.

Sign in to add your message

Back to Top