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adambsmith
22nd Aug 2013, 11:49
This will be my fourth exam having passed Law, Flight Planning and Comms (95%+ in them all) but it's bending me out of shape a bit.

I am doing the mocks from the Pooleys Q&A book and each one requires a PLOG to be completed and then doing 20 or so questions based on the PLOG.

I seem to fall down just getting the true headings right. I start with the route for the first leg, draw a line between the two and measure the angle using a protractor. I try to be as accurate as possible but find that I am always +/- 1 or 2 degrees on my measurement of the angle. I use the lines on the chart to line up the protractor before taking the angle.

Of course if I am out to begin with the error just gets magnified when taking into account drift and variation and I never seem to end up with the answer - always being 1 or 2 degrees out.

I need to pass this exam prior to 1 Sep to avoid any messing under the new EASA rules. I am close - scoring just over the pass mark in the mocks but I want more confidence before going into my club to take the exam.

I know I can do it as I have now done three nav exercises in the air which have all worked well.

Any tips re the above welcome!

Thanks

BackPacker
22nd Aug 2013, 11:59
In my experience the error will not be "magnified", but will remain rather constant throughout the questions. And the answers in the exam paper will usually be at least three degrees apart. So you just have to pick the answer that comes closest to your calculation.

To an extent, the different answers to a question are chosen so that they catch fundamental calculation errors like applying the variation or wind correction the wrong way 'round. Not to fail you on a one degree measuring error.

adambsmith
22nd Aug 2013, 12:04
Yes true.

I just find that if I get an answer to be say 45 which is not an option in the answers then the others are then 46 and 44 (in the Pooleys book) with others being way out. Invariably I get the wrong answer which is infuriating!

G-F0RC3
22nd Aug 2013, 12:15
Adam, from my experience of doing the Nav exam (a couple of years ago now admittedly), I don't recall the answer options being so close. And it wouldn't make much sense if they were. In reality, flying doesn't require you to be accurate to within a degree, and it'd be impossible anyway; the wind is never exactly as forecast. The main purpose of the exam is to ensure you can plan a flight with sensible drift calculations and time estimates etc...

Anyway, good luck. :)

BackPacker
22nd Aug 2013, 12:56
Adam, in this particular case the Pooleys mock exam might not be entirely representative of the CAA exams. If there would be a CAA exam which had choices 44 and 46, and an actual measurement would yield 45, then there'd be too many complaints from examiners and candidates, and the exam would've been changed long ago.

Pooleys doesn't have such a direct feedback mechanism so questions like this may stay in their books for years.

So I wouldn't worry about this. As long as you can do all the calculations properly based on a best-effort measurement, and are consistently within one or two degrees of what Pooleys considers the proper answer, then you're going to be fine.

splidge
22nd Aug 2013, 13:52
Obviously papers differ but I don't remember this sort of trap when I sat the nav exam a few months ago.

I got 100% and don't remember having any serious doubt about the correct answer based on my protractor work although I'm sure I was the odd 1 degree off here and there.

If it really came out that way one possible escape would be to reverse engineer the answers - so in your example you could take the 46 answer and work out what track angle that would correspond to on the map, and then do the same with the 44 answer. Then when you look at the actual map you should have a better idea of which angle is more likely...

Heston
22nd Aug 2013, 14:35
I don't know the Pooley's book so won't comment on that. however you will find that the exam is structured so that it is NOT possible to "reverse engineer" from the available answers.

The OP is right in his concern - if you are a degree or so out in measuring angles then it is possible to go wrong in the exam (its perfectly true that this needs an unrealistic degree of accuracy IMHO, but I didn't write the questions).

My tip for measuring angles accurately - do not draw lines on the chart by trying to judge where the centres of the airfield symbols are because you won't be accurate enough. Instead draw from the edge of the circle of the symbol to the edge of the circle of the other symbol (same edge of course!). Your line will be offset a bit, but the angle will be very accurate.

Also remember to measure the angle approx. half way along the track, not at one end or the other. And apply corrections for deviation etc in the proper order.

Hope that helps.

Pull what
22nd Aug 2013, 20:57
I can assure you as an examiner that the Nav Plog isnt difficult at all. If you cannot measure a track line accurately you have a real problem. Its much more likely that your error is with the whiz wheel. Go over finding Heading and G/S with an instructor as this is usually the common source of error.

Using Skydemon light-plot some single track cross countries and compare the Sky demon results with your own with the whiz wheel. Use several different winds.
#
You also need to do a common sense 'gotcha' check with anything you take off the whiz wheel. Have you got the drift on the right side for instance. Always guestimate the answer before taking it off the scale as a cross check

Lagentium
22nd Aug 2013, 22:26
Adam, I remember sitting down at Sherburn in the room where people take exams a couple of years ago, working everything out and my headings not being the same as the choices on the paper, the delight of multi choice is that two usually stick out like a sore thumb as to being wrong, then you are left with two and use your headings to work out which is correct, well that's what I did and it worked out fine, but if you start with the wrong answer it will lead you down the garden path and the test will be buggered, as a bloke did the same day as me and was a bit fed up. So it's maybe worth making sure everything is correct before ploughing on, but most of all good luck, you have the right attitude by asking questions so its usually those people that pass the tests!

Cheers, Jim:ok:

riverrock83
22nd Aug 2013, 23:07
Just to say - if trying to practice using skydemon light remember that it will change true airspeed with altitude ( such as at takeoff) rather than just using indicated airspeed.
Took me a while to work out why I was always getting the wrong answers...

adambsmith
23rd Aug 2013, 08:01
Thank you all for your helpful advice.

I am getting there although need some weekend revision on the other bits - nav aids in particular.

Will probably take the exam on Monday assuming someone is at the club to do the official bit.

Cheers :ok:

Foxforce
23rd Aug 2013, 13:29
I remember having a very similar issue from the PPL Confuser book and I think I may have got one in the exam. I attributed the error to variability in the computer when calculating the wind correction, rather than measuring the initial angle from the chart.
The exam question I had the biggest risk of losing marks on was an early question getting you to plot the initial angle from the chart and I couldn't find the starting airport. The answer from that question was used for a further 4 or 5 questions. Threw me because I hadn't come across questions using map co-ordinates before, so worth having a wee practice on finding map locations from co-ordinates before the exam. Best of luck mate.

G-F0RC3
23rd Aug 2013, 15:04
Fox, had you not practised finding lat and long before doing your nav exam, or are you talking about a different type of co-ordinates? I can see how that would have been tough if you weren't familiar with finding a location via lat long :\ ... did you still pass on that occasion?

And the PPL Confuser has lots of errors in it, which I found very irritating! :(

adambsmith
31st Aug 2013, 11:37
Thanks again for the help above.

Just took the exam and scored 92% so very happy with that.

Met next.