Gradient pitch

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Nick

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Anyone aware of any formula to change a standard 1 in x gradient into the BVE pitch system?
 
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Tom B

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Yep:

Let x = the gradient of form "1 in x"
Let y = the BVE pitch value

y = x^-1 x 1000
 

Tom B

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If you want a program to do it, try:

http://brj.railuk.org/GRADCAL.ZIP

which I wrote a couple of years back in QBASIC (I think anyway - I also wrote such a program in Pascal, so I don't know which one ended up getting uploaded. But it does the job).
 

Nick

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Shameless plug their Tom to your program, however I can make do with the formula and a calculator! ;)
Ta muchy for it!
 

taw valley

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so if i made the alps with a 1-60 grad

at the end of the thing it would be 16.66667 ? and if its not then your things wrong :P although its probuly right

sorry just seeing if i understand it as well lol incase i ever download the game lol
 

Tom B

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taw valley said:
so if i made the alps with a 1-60 grad

at the end of the thing it would be 16.66667 ? and if its not then your things wrong :P although its probuly right

sorry just seeing if i understand it as well lol incase i ever download the game lol

Nope, it's actually 16.6 recuring, or 16.66667 to 7SF. Though 7SF is a bit much - I usually use 3SF for gradients (what does everyone else use?).

If you're a fan of deriving formulae...

Think of the statement "1 in 60" as a right angle triangle of base length 60 and height 1. Generalise for "1 in x" as being of base length x and height 1.

Since the gradient = change in y / change in x (couldn't find a delta symbol), the gradient would be 1 / x or x^-1 to make it look prettier.

Then you multiply by 1000 to give the BVE value (not entirely sure why, but it works). QED.

OK it's hardly proving FLT but there we go.
 
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