They are Estes A3-6t engines from the late 1970s.
(Correction - made in 1983)
Estes no longer makes the A3-6t engines, there just isn't room for a long delay in the casing.
Over the years black powder has changed. It takes more BP to get the engine up to the proper thrust.
In the inset picture you can see the clay ejection cap is almost to the end of the 1 3/4" long engine.
TRIVIA: The "t" designates "tiny" engines. 13mm MPC and Centuri used an "m" to say "mini". MPC named theirs Mini-Jets, Centuri and Estes called them Mini Engines.
If I'm not mistaken....that "N" date code corresponds to 1983. Nice get, though, and I wish the A3-2T were still available as well!
ReplyDeleteHi Anonymous,
ReplyDeleteThanks for the correction on the manufacturer date. I never quite understood the Estes numbering system. I know it's on the forums somewhere, I should have checked. The A3-2t engines were great, perfect for many models. I guess they figure the A10-3t works in its place.