In answer to EGBKFLYER:
There are 3 main applications of the CRP-5 in JAA exams:
1) You have measured the track (course) off the map, you know the TAS you wish to fly, and you have a forecast wind.
2) You are flying a heading (for instance, a mandatory radar heading), you know your TAS, and you have a forecast wind.
3) You know your heading (after all,you're the bloody pilot - you should know that - you're flying it). You know the TAS - you've done some work during the flight planning process. You can find your track and groundspeed - either you pass over 2 successive fixes and you use them to find your track and groundspeed, or you've got INS, or (if it's a very old aeroplane) - you've got doppler. So now you've got heading and TAS and track and GS. Using the CRP-5 you can now find a wind. This will be more recent and more local than your met met forecast.
(Look - I know some of this stuff sounds a bit old-fashioned - but I don't write these exam papers - I just prepare students to answer them - OK?)
You will find an equal amount of all 3 types of the above questions above in the average JAA exam. If you want to pass - then you have to be equally good in answering all 3 types of question - because you can expect about 8 of each type to turn up in the exam. Do you want to throw the exam away because you haven't prepared 8 of the 24 of this type? As Dirty Harry says - do you feel lucky, punk?
No. So any sensible bloke (or girl) who wants to pass this exam will get equally good at all 3 types of question.
THE ONLY WAY TO DO THAT IS WIND DOWN!!!!!!! Otherwise you have to learn wind up technique for finding heading from a known track, you can (just) by bodging it, find W/V from wind up, but there is NO neat and easy way for finding track from heading from wind up.
Honestly, guys and girls - use wind down technique for all 3 problems - it's so much easier, once you get used to, it works for all the problems, and it's consistent. Wind up method is only suitable for PPLs who are not going to go on to CPL or ATPL and only need to be able to find heading, given track. But it's useless for the other 2 problems - WHICH YOU WILL NEED TO BE ABLE TO DO EQUALLY WELL IF YOU WANT TO BECOME A CPL OR ATPL!!!!
Sorry about the capitals, but I see so many stupid opinions on this subject, and I haven't come to these conclusions lightly.