John

In fact I am not concerned about a crash, because in that event the small gas bottle might be the last of my concerns.

A while ago, I remember a jet caught fire in flight and in the event of a gas leak during flight, if it reaches the exhaust it sure will catch fire. With a filled small gas can, I only need to fill it once to fly several times and that is why I'm using it.

My concern is to have a redundant safety valve to avoid such an event and a manual valve might be a good option.

Do you rely only in a oneway valve?

Regards

Nuno