[michaelt]

What if the 81mm also refers to the inner diameter of the tube that is used to launch the rocket?

[Zeppo]

Yes, if they are implying that the tubes were intended to serve as rocket housings rather than launch tubes.

It is my understanding (but I can not quote a source off the top of my head) that no other components were found by the ISG to have been part of a procurement designed to produce either 81mm rockets, or tubes to launch rockets, and that therefore it is nothing more than idle speculation to claim that the tubes were intended for use in rocket or artillery launch applications...

[Wristpin]

The letter states the inner diameter is 74.4mm. Is that still suitable for 81 mm rockets?

[mjaneangels@aolcom]

"What if the 81mm also refers to the inner diameter of the tube that is used to launch the rocket?"

Good question, but the document indicates that the 81mm is outside diameter with an inside diameter of 74mm with a thickness of 3.3 milimeters or a little over 1/8th inch. I haven't converted the inside and outside diameters to inches yet. Let me know if you want me to.