I would just set up a state machine. Normally you read the speed values into the AnimBP anyway.
Hook into that and remember that normally 5% is .05 NOT .5 which is 50%.
Speed is it’s own thing though, you have to figure out what your max speed is and precompute the math. OR, you can convert it with a map range clamp to go from the actual values to 0 to 1 and get back to the stuff below.
Like a jump, 3 states for it. Transition in, hold wings open, transition out.
Similar to a jump, enter if speed is > .05, remain in state until speed is < .05.
The transition states both need to have loop disabled and a rule to transition to the next state based on the animation having finished (you should be able to click the auto transition checkbox too).
Since this is a constant behaviour the way you describe it, there is no need to trigger anything except for to read the speed and utilize it as the starting point for animations transirions.