At lease one accident of a B-2B has been caused by Mud Dauber wasps:
The pilot reported that he "...lost fuel pressure which resulted in engine failure." A postaccident inspection of the aircraft and its records by a Federal Aviation Administration (FAA) Aviation Safety Inspector revealed that the fuel overboard vent tube assembly was clogged. The FAA Inspector stated: "Cutting open the tube near the open overboard vent end...resulted in finding insect and nest remains that filled the tube. The vent tube was plugged in at least two places and a third plugged location was not opened up for examination."
The full report can be found by selecting the following link: N2261U
Bottom line is that Mud Daubers are dangerous. They will crawl inside of the smallest holes and build their rock-hard nests out of mud. For those of you in areas that have these wasps, it would be a good idea to cover or tape up the holes on rotor blades, pitot tubes, exhaust pipe, fuel vents, etc. when not using the helicopter. They build the nests very quickly, sometimes in less than a day.
Attached is a picture if you have not seen one before:
I've pretty much read every post on this board. The value of this board for Brantly owners is immense. Since I'm getting ready to start my Brantly I've been trying to final check everything. I checked the fuel vent line and it looked clean as a whistle. Stuck a piece of safety wire up it several inches-clean as could be.
But here was a fatal accident that might have been caused by a blocked vent. I removed all the lines from the little header fuel tank. The line from the header tank to the bottom of the fuselage(vent overboard line) was plugged tight as a drum about in the middle of the line sight unseen! Took a lot of air pressure before the clog let go and blew out the other side. The two fuel tank overflow lines to the header tank and the header tank itself all were okay. Better keep an eye on this-and don't just assume it's open even if it looks "clean" for several inches!
