PDA

View Full Version : Whizzy Wheel Drift Help Needed!


baldwyn
20th Mar 2009, 19:44
Hey,
I've had a quick search on here to no avail hence my post :p
Got my navigation exam tomorrow, need some help mastering the drift aspect of it all.
I can get the drift correct +/- 1 degree but I'm unable to see which way to "turn" - I've tried visualizing it in my head i.e. Wind at 090 I'm flying at 100 so need to turn towards N to counteract it. Somehow doesn't always work?!
Anyone got any tricks/tips/methods that I can use?

Thanks In Advance.

POT NOODLE HORN
20th Mar 2009, 20:04
How about postponing your exam !!!!!!!!!!!

Hope it helps :ugh:

baldwyn
20th Mar 2009, 20:06
Not really, lol.

Put1992
20th Mar 2009, 20:58
If your using the wind up method, if the cross is to the right, you add the drift on 'to the right', if it's to the left, you take it away 'to the left.

Or just think about it.

Heading east, southern wind, you will have to turn towards that wind to the right

Comprende?

jxc
20th Mar 2009, 20:58
Tip

Read the book again and seriously think about postponing the exam this is PPl ?


Cheers

baldwyn
20th Mar 2009, 21:03
Right, Cheers.

I'm going to practice on it tonight and I've got an hour of groundschool tomorrow as well. If at that point I'm still wary, I'll cancel it until next week.

RatherBeFlying
20th Mar 2009, 21:48
If the whizz wheel is confusing you, drawing a vector diagram might help.

Or you can separate the wind into head/tail-wind and cross-wind components.

x-wind from right, correct to right
from left, correct to left

or just turn into x-wind

liam548
20th Mar 2009, 22:06
i had same issue until i just practiced and posted some threads on here. I use OAT PPL CD rom.

Managed to pass nav today without even using the books, just the cd roms.


Confuser is a very accurate example of the exam. You get one PLOG to complete and one route to draw and about 18 of the questions are on this so be very accurate with your PLOG.
Then last 5 are on Nav Aids.

baldwyn
20th Mar 2009, 22:15
Yeah, I've got the CD's for Law + Nav. Very useful - I do read the books as well as it puts everything into a different perspective which is useful when trying to learn it :8
Haven't got the Flight Comp OAT CD However, it's a pain that it's separate:*

Rightbase
20th Mar 2009, 22:19
I have a .pdf that might help - check your pms. Anyone know a good way of sharing a .pdf on here?

liam548
21st Mar 2009, 16:09
i learned the wind down method and it makes sense to me now. There was just one example I could not figure out which I posted on another thread and still cant get the right answer.

The OAT disc really does help as it talks you through it and you can see it as it moves on screen. Plus you can practice quickly with unlimited questions and it tells you if you are wrong or right instantly.

baldwyn
21st Mar 2009, 18:40
Worked hard, nailed it - Took exam - 80% :D

Thanks for your help everyone.

The method I was taught just before the exam is as follows.
1 - Set wind on index
2 - Set blue circle on 0 on bottom part of the scale
3 - Draw a dot for the wind
4 - Set Track
5 - Draw a straight line downwards from the dot - a few cm. Ensuring it's straight and parallel to other lines.
6 - Set blue circle on TAS
7 - "Twist" the wheel round until the line is in line with the other lines ( Makes sense? :p )

This is accurate to a few degrees so it cannot be used for exact measurements. More of a double check to ensure you're going the right way and are roughly in the right area.

liam548
22nd Mar 2009, 00:58
Worked hard, nailed it - Took exam - 80% :D

Thanks for your help everyone.

The method I was taught just before the exam is as follows.
1 - Set wind on index
2 - Set blue circle on 0 on bottom part of the scale
3 - Draw a dot for the wind
4 - Set Track
5 - Draw a straight line downwards from the dot - a few cm. Ensuring it's straight and parallel to other lines.
6 - Set blue circle on TAS
7 - "Twist" the wheel round until the line is in line with the other lines ( Makes sense? :p )



This is accurate to a few degrees so it cannot be used for exact measurements. More of a double check to ensure you're going the right way and are roughly in the right area.


join the 80% nav exam club then.. thats what i got yesterday.

I would like to know when we would want to calculate the wind in real life situations?

Mark1234
22nd Mar 2009, 13:06
The method sounds horribly complicated. Only whizz wheel I've ever had is the completely round one CR-something springs to mind.

With that, stick a dot on the disc for the wind direction, and that's the only drawing required. Rotate the disc to heading, it gives you the head/tail and cross components. rotate the outer disc to the airspeed, and read off the number of degrees against the knots. very doable in flight. Might be worth looking at as an easier solution.

Tinstaafl
22nd Mar 2009, 18:11
Yeah, I favour CR types against slide types too. Little chance of 'em becoming popular in the UK. Ignorance & inertia from the instructing community, I think.