912UL fuel line & fitting size clean up (video)

Hi John Clark,

Reference; Hose fitting AN (threaded) V Push On

While I support individual choice, its important (at least to me) that the option -  Certified AN style threaded fittings be subjectively compared with the alternative - Push On.

Non Certified Rotax 9 engines around's the World have & continue to use, push on hose fittings, with no apparent significant reduction in safety outcomes.

"....certified aircraft use AN ....." 

In Australia small aircraft that are used for hire/reward must be Certified. The standard for Certification has come about through the hard lessons of history (aircraft incidents/loss of life) AND an over abundance of caution, due to litigation. The later, often impacted by perception rather than genuine risk analysis. For private flying & home built  aircraft, the standard is lower - this is not to suggest that such aircraft are any less safe. In fact its a recognition that Certification has, in many instances, gone too far, resulting in unnecessary cost. All Government authorities are averse to winding back supposed safety legislation, even when demonstrably ineffective. The result -  we accumulate regulation, much of which does not reflect changes in technology or research. A push on fitting, correctly executed,  is no less safe than a screw on (AN) fitting.

We fly in a hostile environment and safety matters but must be tempered by reality. Aspiring to Certified standards will, in many instances, just increase cost, without significant safety improvement. Ultimately this will economically exclude many from our activity (already happening?)

"....instead of garden hose barbs..."

This is, at best ,an ill informed hang over from the historic use of multi barb, usually brass, plumbing style fittings, at worst the sort of colourful rhetoric that serves no one well. Modern automotive style spigots are; secure, dont leak (assuming correct hose ID) or damage the hose, comparatively light weight & cheap. This style of spigot is supplied by Rotax for oil, fuel and coolant fittings and can be found on every  ground based vehicle less than 30 years old.

"...stainless and fire sleeved teflon hose with firesleeve and AN fittings."

Other than aesthetically pleasing, delivers comparatively minimal safety improvement, at much greater cost and weight.

 "....barb fittings just look wrong on an aero engine..."

This is an aesthetic statement that has no basis in function or safety outcomes. If fitting something that satisfies your aesthetic inner self, go for it ! Please don't try to justify it from a practical point of view.😈