Calculator use on the ATP Written
 

Looking for some gouge on the use of a calculator when taking the ATP written. I know calculators are allowed and a fistful of problems on the test require straight up aero formulas (convert Mach to TAS at a given alt and temp), but i've also heard there is a built-in calculator as part of the ATP testing software. So 3 questions:
- Can anyone validate whether the ATP written test includes a calc?
- If so, is that calc sufficient, or are you better off bringing your own?
- If there is a built-in, do you know of any on-line modeling for their calc, so you can practice on how to use it, before showing up for the test.
Thanks!

There are two testing systems (CATS and Lasergrade), so there might be some variances in what each system provides. I took mine on CATS, and I believe there was a simple math calculator available as a pop up but without aviation functions it's not really useful.

However, my recommendation is to buy an FAA testing-approved calculator with all the aviation functions. If you're like me you use a smartphone for all flying ops - which isn't allowed. So buy it from Amazon, practice with it while prepping, use it on the test, then return it when done since you likely have a good calculator on your phone. Simple.

I tested under the old system and used Sheppard Air so think I broke out the calculator only once or twice. With their gouge you likely know most of the math answers ahead of time.