I did have problems with E12's and E16's in the past. Below are my most recent results:
2020 E16-6 Two flights. One perfect, the second did not build up as much thrust as it should have. Chute did not open in time. A 4 second delay would have resulted in a good recovery.
2022 E12-4 Fourteen perfect flights.
2023 E12-4 Seven perfect flights so far.
The E12-4 is now one of my go to engines.
