When did you start the game - 1900 or 1920?
1920
What nation were you playing?
Japan
Were there any start options that were not the default?
Yes. Varied Technologies and slowed research rate.
Describe the issue in detail.
By 1933 all AI nations had acquired torpedo bombers. I had not acquired such. In an other play through as the U.S I encountered the same issue and I wasn't able to research dive bombers nor torpedo bombers by 1940.
What were you doing when the bug occurred?
I wasn't in a conflict nor in a battle. Just sitting on the fleet overview.
What did you expect to happen and how was the result you saw different than you expected.
I would've expected to research at least torpedo bombers by 1928sh.
Can you describe how to reproduce the bug?
No idea. Something with a line of code?
What version of the game were you playing (v1.00, v1.01, etc)?
v1.22