At the Cold War Air Museum, we are again working on the MiG-23.
The 23 has an unusual ventral fin for added stability in flight. Here it is shown retracted to the side so that it does not scrape the ground on landing or take off. Fin retraction is tied to the landing gear system. It automatically extends when the gear is retracted and retracts when the gear is extended.
We were able to see this (and a lot of other things as well) while checking some of the hydraulics and the gear system yesterday. Sean, one of our volunteers, captured several clips of the gear and ventral fin and provided them to us for the blog. Thanks Sean!
At the beginning of this clip the gear is being retracted and the ventral fin can be seen moving to the down position. Almost immediately the gear is extended again as the camera shifts to a different view. Upon full extension, the view quickly shifts to the tail to show the fin flipping back to the side again.
A young man recently visiting the museum called the MiG-23 a "Transformer" plane. Like the action figure series, it has lots of large moving parts and is capable of some pretty fancy reconfiguration. The clip below shows another view where at first you can almost imagine a mechanical arm reaching out from some large mechanical war machine. Oh yeah, in reality, that's pretty much what it is.
The video continues long enough to again show the ventral fin changing position under the tail (the "click" noise associates with the fin unlocking to change position).