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liam548
25th Feb 2009, 15:34
I'm on the nav part of the PPL and wondering what method people use when calulating heading on the old whizz wheel.

If the wind up is easier why is there even mention of the wind down, what are the pros and cons of each method?

is a particular method better suited to commercial flying training?
Liam

soay
25th Feb 2009, 15:58
Get a whizz wheel with a wind arm (eg. CRP-1W) and you don't need to worry about which method to use. It's more intuitive, quicker, and there's no pencil mess to clean up. I've never understood why they make them without it.

Mike Cross
25th Feb 2009, 16:10
I use wind up because that's the way I learned to do it. I find it totally intuitive and easy.

Makes no difference IMHO which way you use it, just use the way you're happiest with.

That said I now tend to use Navbox Pro 'cos it does everything else for me as well, including looking up and printing the frequency list. Also does w&b and fuel burn and is less prone to artithmetical errors.

However before you start doing that make sure you are totally at home doing it the mandraulic way, then you won't get caught out if plans change.

Redbird72
25th Feb 2009, 16:28
I was taught wind down by my instructor, but the Trevor Thom books appear to favour wind up.

I've just stuck with the method that was taught to me, to aviod confusion in the briefing room.

Whopity
25th Feb 2009, 17:02
Look at the Computer and ask yourself one simple question: Which way was this designed to be used? If you can't work it out, it probably won't make the slightest difference if you use it back to front, upside down or inside out!

liam548
25th Feb 2009, 17:06
Get a whizz wheel with a wind arm (eg. CRP-1W) and you don't need to worry about which method to use. It's more intuitive, quicker, and there's no pencil mess to clean up. I've never understood why they make them without it.

I got sent one of these but found that it was harder to read the answers off accurately enough for the confuser questions.

I therefore sent it back and asked them to replace it with a normal one without the wind arm!

IRRenewal
25th Feb 2009, 19:59
Both methods work.

Use the one you are most comfortable with.

If you have an instructor who can only teach one method and insists you use that method, find a different instructor.

Deeday
25th Feb 2009, 21:59
Wind-mark-up is undoubtedly better because it requires fewer steps than wind-mark-down (it's a direct method, as opposed to iterative, if we want to be pedantic).
The reason why people still use the wind-down is because they've been taught so by other people who had been taught so by... [repeat at will]. It's not a coincidence that on the Air Pilot's Manual the wind-up is presented first, and then, for completeness, the wind-down is included.

Remember! Smart people use the wind-mark-up, the others just keep jiggling the wheel ;)

Deeday

stiknruda
25th Feb 2009, 22:19
Wind down - 'cos that really shows the true vector diagram. Yes it might entail a wee bit of shuffling at the end to get the drift/hdg correct.

I was taught this method 30 years ago at 6FTS and it works. I understand the wind-up method and have helped "mates" with it. When the answer in the book does not agree with wind-up, I can by using wind-down get the right answer.

IF you understand the vectors - you won't go too far wrong in real life.

Horses for courses, really.

Deeday
25th Feb 2009, 22:44
Wind down - 'cos that really shows the true vector diagram

I don't get this one. The triangle of vectors is obviously the same in both cases; the only difference between -up and -down is which vector you line up with the wheel's centre line.

Horses for courses, really.Yes and no: the problem is one and there is only one solution, no matter which method you use. If you get different results, most likely it's because the wind-down has not been iterated to a sufficient precision (or precision has been lost from step to step). True, if an exercise has been prepared using the wind-down, then by applying the same method (with same iteration errors) you are more likely to get the correct answer (which is a reason good enough to use the wind-down, in this case!)

Deeday

mad_jock
25th Feb 2009, 23:56
Wind down is the method used for the commercial.

You can do more with the wind down method ie you can't answer all the questions in the gen nav paper if you do the wind up. Unless the exam has changed you had to do 10-12 questions using pretty much all of the functions on the wheel and work out the third side of the vector triangle using the derived data for the other 2.

To be honest after sitting that paper I haven't used the thing since apart from showing PPL students how to work it and using the board to scape the ice off hire car windows.

When you do the CPL you get discouraged from using it (well I did) and just use rules of thumb to work out the drift and leg times.

Whopity
26th Feb 2009, 08:17
The reason why people still use the wind-down is because they've been taught so by other people who had been taught No the reason is because thats the way it was designed to be used. Try reading the words written on the outer bezel Drift Left, Drift Right! If you had used any of the additional slides we used in the military, CARP, HALO, MEARS etc its the only way it can be used!

Mike Cross
26th Feb 2009, 08:56
I use wind up because the original Jeppeson Flight computer I used when I did my PPL in 1974 had instructions that said do it that way. Ergo it was "designed" to be done that way.

If you want the sum of 3 and 4 then 3+4 gives you exactly the same answer as 4+3, one isn't "right" and the other "wrong".

The E6B is simply a handy way of doing something you would otherwise do on a map, ask any navigator who's crossed the channel by boat and plotted the tidal vectors. If you're going from A to B you can draw the drift in one direction at the start point or the opposite direction at the destination in order to arrive at the course to be steered. They both achieve the same result. Try it!

Not at all sure which method Philip Dalton (http://http://www.flyingstart.org/apps/obituaries/MemorialWall2.aspx?ID=1277) advocated when he invented it.

usedtofly
26th Feb 2009, 11:37
wind up or wind down method?Personally, I like to wind up my co pilot in the afternoons, then wind down with a glass of wine in the evening :E:E:E

VFE
26th Feb 2009, 11:50
If you are planning to go on to commercial level I would suggest wind down as it allows you to obtain other answers to questions much easier.

VFE.

Whopity
26th Feb 2009, 13:57
Not at all sure which method Philip Dalton advocated when he invented it. As the Military are probably the only users of a "Dalton" Computer then its Wind Down.

If you own a Douglas Protractor, look at the inner scale, it reads 0 -360 in reverse; then compare it with say an Airtour Protractor and you will see it is calibrated in a totally different way! How many know how to use the inner scale on a real Douglas Protractor?

Mike Cross
26th Feb 2009, 16:00
And the other side's just a graphical representation of a set of Log Tables that allows you to add or subtract two logs to do multiplication or division, together with a few conversion factors marked on it. Oh how I remember the competitive slide rule comparisons at school. How fine is the engraving? Is it a magnifying cursor? An E6B is very crude by comparison.

I dare say we could discuss kneeboards now:E

liam548
2nd Mar 2009, 14:34
Im sticking with the wind down. All strasight forward but when it comes to re adjusting after the i initially moving for drift Im finding it difficult to work out of i should adjust in a clockwise or anti cllockwise direction...

Liam

Cusco
2nd Mar 2009, 20:00
I'm frankly amazed that we still have to p*ss about with CRP 1s and 5s. with the wealth of electronic gadgets now available.

I gave up using the slide-rule (that's all a CRP is) when I left school in 1963.

Even log tables (hands up who remembers them?) are no more.

Time for flight training to come into the 21st century.

And yes, Ive got a CRP1 and bought a CRP5 last year out of necessity............

Cusco.:ugh:

TheGorrilla
3rd Mar 2009, 01:08
Wind up, down, left, right, couldn't care less..... Tis the big picture in your head that matters most. That's why we have instruments and gadgets and it really doesn't matter how clever they are if you don't have a clue.

Spend more time thinking about the vectors involved and the big picture and less time about the silly bit of plastic you're twiddling away with.