I am still trying to hunt down what could possibly cause this. As I mulled over it the last few weeks, it dawned on me that
- Our DLE 61 engine was not grounded to the system’s power ground.
- When installing an EFI on a DLE170 on previous project, I used to connect one of the engine’s fins to the battery ground. However, on the airplane that crashed, because it was on a carb, it didn’t cross my mind to also do it.
- The hypothesis is then: because the engine had no connection to ground, the engine built up charge and released it into the system (possibly via the ignition), causing something inside the Pixhawk 2.1 to transiently behave really badly
- Something else that we are also grappling: why is it that we didn’t see anything amiss with our servos during our 1 week of post-integration shake down with the engine (where we put the system through its paces by revving the engine and running it for long hours) on this system when it was integrated? Could it be that the charge was discharging to the ground?
- It seems like the only was I could “try” to “replicate” this is to “shoot” the system down with a ESD gun
@tridge Is the engine of Canberra UAV’s OctoPorter connected to the battery ground (i.e system ground?)
- Additionally, on another note: can I also ask if your team are still using a fuel pump with the engine and if so, which one are you guys using?
Thank you!