Door Opening in flight?

[Ernie Martin]

The upper door has flown open twice on my 337G normally aspirated. Both times pilot error, where I failed to lock the safety pin down.

I share the view of others that the mechanism is robust and open doors are almost certainly pilot error. Locking the pin down is now not only part of my checklist but I always tell whoever is on the copilot seat to remind me before takeoff.

Ernie