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Ground speed check guidelines
henrik created the topic: Ground speed check guidelines
I came across a question in the online practice exam regarding syllabus item 126.96.36.199 [d] which relates to ground speed checks.
It's probably a bit of common sense, but are there any guidelines regarding the use of suitable features to perform ground speed checks with? If I remember correctly the question gave options of homesteads, rivers and roads at various distances from the initial fix.
rossy replied the topic: Re: Ground speed check guidelines
Hey, just letting you know that i did my test on wed and there were no such questions in my own exam, any q that req figuring things out gave the g/s. a couple of 1 in 60's, quite easy and all two marks. Were a few q's on bod and eod and also similar ones to the bod and eod and a planned flight asking the max hrs possible for flight etc. Pretty straight forward and nothing you wont have seen in the text.
bobtait replied the topic: Re: Ground speed check guidelines
There are a couple of points worth remembering for ground speed checks.
1. Don't attempt to check you ground speed over a short distance. It is impossible to get an accurate ground speed over a distance like 20nm. You cannot time it accurately enough and one minute would make a huge difference to the answer. The longer the distance the better, but don't waste you time if the distance is any less than 30nm.
2. Pick a line feature [straight river, road or railway line] that crosses you track an approximately right angles. That allows you to be a little left or right of track and still get an reasonably accurate ground speed. A line feature that crosses track at a shallow angle will give very different answers if you are a little left or right of track.
3. Don't use an abeam feature if it is more than a couple of miles off track. It's surprisingly difficult to accurately assess when you are abeam a feature that is a long way off track unless you use a nav aid such as ADF or VOR.