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Lumps
21st Jul 2017, 23:11
Seems like it's the natural successor of the venerable (not vulnerable) J2B. Did Lycoming's FADEC boffins go against much of the Lycoming PR department's recommendations regarding LOP operations?

Following on from the Navajo spar thread, turbines a great, no argument there, but I wonder if piston powered aircraft would enjoy a better reputation if the industry was better educated on engine management. In this area the Chieftain AFM is actually pretty good, except for the high power leaning bit, even publishing LOP procedures as many would know.

However, seeing as not all pilots have real interest in the red levers I wonder how much of say the PT6 or TPE331's reliability advantage actually comes from the fact that they both pretty much remove the possibility of white shirt wearing airline wannabe's ability to screw things up. Save for blowing a few very simple limitations.

On the contrary the traditional aero piston engine gives the operator great freedom, and with freedom comes responsibility. Pilot's can't be blamed for not being interested in them to the level required to do things properly, many are off to JetA stuff asap why invest the brain cells.

So engineer out the pilot's ability to screw things up (FADEC) and maybe piston engine's MTBF would start closing in on their turbine counterparts' that by their very nature have negated much need for an educated pilot to operate reliably. From Honeywells marketing publication the TPE331 series has a MTBF of a bit over 60,000 hours (memory item, can dig up reference). Googling this subject turn up some wildly different figures, but this is from the manufacturer, who is naturally promoting their wares.

Of course, this would be contingent on the maintenance community coming along on the education ride too, being able to interpret the data from the EDMs correctly and a few lessons on oxidisation for owners that leave piston aircraft to sit uninhibited in hangars at 90% humidity for months on end...

A lot of work! Perhaps this is why we have collectively accepted spalled cam lobes (corrosion) and cracked cylinders (high temp & pressure) as just inherent to the world of piston bug smashing. I'm generalising here of course, to make a point.

lo_lyf
22nd Jul 2017, 09:10
We've collectively accepted multiple jug changes per TBO as inherent because we've all been taught that the POH is your bible. The green arc goes up to 500degF!

In the near future I don't think we'll see enough of these engines flying to skew the figures in the favour of the FADEC piston engine. And from a narcissistic pilots view once a piston engine is FADEC they've eliminated the opportunity for me utilise my knowledge. It may as well be a turban.