Don't use chinagraph pencils!
Contrary to popular belief, Chinagraph pencils are about the worst thing you can use to plan a route. Remove it from your flight bag and put in the bin!
Why? Lots of reasons:
1) They look like a child's crayon mark on your aeronautical map, not very professional.
2) The thickness of the lines they produce can make measurement of track inaccurate to a whopping 4 degrees!
3) They are expensive.
4) In warm temperatures, they turn to mush and are virtually impossible to sharpen.
5) Can you even find a sharpener with an orifice big enough for one of these big daft clunkers?
I could go on and on, but I’m sure by now you get the picture. The main gripe is, they make measurement of track direction inaccurate.
So, what should you use?
A nice ‘fine’ (not medium/thick) Staedtler ‘permanent’ marker. That’s right, ‘permanent’. Why would you want to use anything else? Non-permanent will disappear with a sweaty hand in the aircraft, not the best plan when you need to see if you’re on track! A permanent track line isn’t going anywhere. I would also suggest using ‘black’ (least used colour on an aeronautical map). Any other colour will inevitably cover up a motorway, river, woodland landmark etc. Black, Permanent and Fine (thickness) is best!
How do I rub it off then if it’s permanent?
NOT with nail varnish remover! Why? Again, lots of reasons:
1) ‘If’ you’re a chap, who wants to ask their Mrs/Girlfriend if they can use their nail varnish remover? If you’re a girl (or a guy who’s called Suzy at weekends), then I suppose this won’t be an issue for you.
2) It’s smelly.
3) It’s corrosive to your chart and with prolonged use it will eventually cause map de-lamination and all the colours will look crappy and faded.
4) If it leaks in your flight bag, then good luck. My friend had a bottle of his girlfriends nail varnish remover in his bag (he said it was his girlfriends) and it leaked out and destroyed a £2,000 Garmin GPS, £900 Bose Headset, £800 Portable TCAS Unit and a few other bits and pieces. Total damage, well over £5,000. Ouch!
What should you use thats any better? A rubber? No, they’re rubbish too, they’re messy and take a lot of effort to shift permanent pen.
A simple cheap and chirpy ‘dry wipe’ board pen. Simply run it over your permanent tracks, leave for a few seconds, then wipe off with a piece of kitchen towel / tissue.
It’s a simple but very very effective tip. Oh, by the way, keep the pen to fine thickness because that enables you to measure track to an accuracy of 0.5 of a degree. Even an Airbus autopilot cannot fly to that level of accuracy.