I have been experiencing this as well. DCG3.46 with HSFX 5 class files. running 4.10.1 with HSFX5.1 with DCG replace DGEN full auto generation mode
It seems to happen if any of the following are done:
1. you edit the master mission and add objects such as buildings, tents, oil drums etc
2. you change any aircraft to a modded a/c (but not all modded a/c are the culprit, just a couple of offenders)
3. you add airfields and do not add take off co-ordinates to the airfields.dcg file
4. you have more than 1 squadron spawning at an added airfield
It does NOT happen if ALL aircraft are set to airstart
Although one strange thing happened in a mission the other day, one of a flight of two rufes did the bounce/bent prop trick at mission start
the other started fine.
I have also noticed that sometimes the FMB refuses to load a dcg generated mission, it just sits there and does nothing
I have also noticed that a modded aircraft will appear in external view as bright mauve with bent prop, seems to always be a mod Hurricane that does this
Here is a mission that was generated by DCG and all planes explode at start (except the airstart planes)
https://www.mediafire.com/?q5l47wk4czbgd70