I have this with the posky 757 a lot. It happens when I do a replay of a take-off. (which is what you did for your screenshots!) When the replay starts, the undercarriage is still retracted so the plane gets damaged (sparks and smoke; with the 757 they come from the nose as well, which looks very strange). In the replay the main wheels will only extend completely when the plane leaves the ground after take off. If I resume the flight after the replay the damage is still there and never goes away until I restart the flight. I find this annoying

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To prevent it I'll lower the gear before starting the replay, that does the trick for me

Other option is to make a flightvideo of the take-off instead of using replay. Then it doesn't happen, plus you lose the "replay XXsec" message in your screenies
Cheers
AJ