Hi Flakbait,
>One ATA is one atmosphere (29.92" Hg or 760mm Hg) and it can be readily converted into PSI, InHG or anything else you want without any math what-so-ever.
Actually, ata and atü are based on the "technical" atmosphere of 1 kp/cm^2, while atm refers to the "physical" atmosphere of the international standard pressure P = 101.325 kPa.
Math is still required :-)
Regards,
Henning (HoHun)