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172_driver
12th Mar 2011, 08:59
Interested in hearing some opinions from other pilots on a particular scenario.

In a 1 min holding pattern we normally apply 2-3 Wca for crosswind on the outbound leg to give some space for a wider turn radius as we turn inbound. Assuming traditional technique and no variation of bank angles.

Do you apply any corrections on the offset entry leg, let's say you have a pretty strong crosswind for the type of plane you are flying? Normally we track 30 deg offset on the outbound portion of the teardrop. Would you increase this angle as appropriate to avoid overshooting the inbound radial? I am not sure what is most beneficial obstacle wise, to stray a bit extra further out on the holding side or overshoot the inbound turn into the non-holding side? I have never seen any literature deal with this scenario and I can understand it comes down a bit to personal technique and experience. Like most things in aviation are negotiable I am asking what you would do? Mostly concerns drivers of low speed machines.

Morrisman1
12th Mar 2011, 09:10
If the hold is over a VOR then an easy way to do it is to fly along a radial 30 off the outbound track keeping within the holding pattern, this way you don't really have to worry too much about drift, just track like you normally would in a crosswind situation.

It would work for NDB too but not quite as easy as with a VOR.

In nz I believe the wording is track outbound for an appropriate time, so its up to the pilot. In the seneca it was about 45 seconds. If wind was blowing me towards the inbound leg while tracking outbound on the offset entry then I would extend that time to maybe a minute, if wind was blowing me away from the inbound then it may be possible to get away with a shorter time.

172_driver
12th Mar 2011, 09:14
Yes, certainly would I aim to track 30 deg offset, no matter VOR or NDB. The question was more, would you increase the angle from 30 to let's say 40 deg in order to compensate for the larger turn radius as you turn inbound? Thanks for reply though.

eckhard
12th Mar 2011, 19:05
In the 747-400, the FMS seems to track about 40 degrees from the inbound leg, whatever the wind. It also varies the bank angle to achieve a constant-radius turn, so I realise this is not exactly relevant to your question, but hope this info is helpful.

172_driver
13th Mar 2011, 05:42
Thanks Eckhard, interesting info!

BOAC
13th Mar 2011, 12:05
172 - you are protected all around the holding pattern on both sides at initial (joining) hold altitude (otherwise you would only be able to join the hold from the holding side?) so 'obstacles' are not really a consideration. It is just VERY untidy (in my opinion) to fly through the inbound radial and makes it sooo much harder, so yes, I would 'correct'. I think in your 172 in a 'howling crosswind', if you wished to have a chance of 'catching' the radial......................:)

Microburst2002
13th Mar 2011, 14:53
In my opinion.

- Fly overhead the fix
- turn to outbound heading (no WCA)
- after one minute turn to the fix (do not intercept the inbound). Just turn to the fix. If TAS and windspeed permit, you can intercept, of course. But if you are too fast and wind is blowing from the "wrong side" don't worry. Fly to the fix.

172_driver
14th Mar 2011, 05:36
Thanks for your inputs... many techniques out there to achieve the same goal. Personally I am also the "pedantic" type who considers it untidy to shoot through the inbound radial.... I was just asking because I see my students neglect the effect of wind every time..... "ahhh they just don't get it :ugh:"... until you think to your own time as student..... :)

sevenstrokeroll
14th Mar 2011, 09:12
you should do your best to navigate the holding pattern properly...but unless you have alot of gadgets to help you, you will be ''experimenting'' all the way around until you get it right.

I've dealt with winds aloft across the holding course of over 100 knots..

the best advice is also the best description of a holding pattern.

LOST IN THE VICINITY OF A FIX


sort of like the game of golf: a good walk in the country...spoiled.

by the way, after you have spent four or five times around the racetrack pattern, and you have just gotten it right...you will receive further clearance.

AND ALWAYS WORRY ABOUT terrain and make sure the holding clearance is proper...a friend of one of the best pilots I've ever known crashed into the side of the Wasatch mountains because ATC gave the clearance in an incorrect manner.

BOAC
14th Mar 2011, 09:20
As an old TRE said to me many years ago:
"Your first hold (and your entry procedure) counts as a 'free go' but make an effort to get it right. Your second/actual hold after entry had better be right"