This SAE Aerospace Standard (AS) defines an involute with a 30\mD pressure angle and a full radius at the roots thus reducing the stress concentration in the area of the root.
SAE AS84C History
More Standards PDF
SAE AMS3323B
$37.00 $74.00
SAE AS6060A
$87.00 $175.00
SAE ARP1088C
$34.00 $69.00
SAE AIR1289A
$50.00 $101.00