Bill:
Some (quite restricted) "user data": A 1 mm Phenolic-Liner (Hp 2061) in a
38 mm OD casing will withstand a 1 second burn of APCP (no Al or other
metals added) in a free standing BATES-grain configuration without any
problems. It will be coked after a 5 second burn with the same propellant
in an end-burner configutation but will still save the aluminum-casing
(wall thickness 2 mm) from a burn-through (just some discoloration of the
anodic coating). I can provide photos if desired.
Hagen
Troy:
Let me add that given 0.8 mm and a (conservative) 1.2 second burn, it follows that this liner was good for about 0.66 mm per >>>second, implying a need for 6.66 mm for a 10 second burn.
With enough similar data it will be possible to estimate a number, with variance, that at the low end allows for a (probably) >>>safe flight.
Bill