Different engines possible?

[Morne]

Originally Posted by Ernie Martin

Your safest aircraft is a well maintained certified aircraft.

Ernie, I appreciate your point of view, but hasn't the 550 been STC'ed for the Skymaster? Thus, isn't a Skymaster with a 550, be it one or both engines, still certified?

As to other ideas, like diesel, again I'm talking about once it has been STC'ed. I have no desire to be a test pilot. The diesel thing, addressed more thoroughly in its own thread, is a longterm option for dealing with the 100LL problem.

I don't have a MS in Mechanical, but I am a degreed engineer. I worked as a Metallurgist for a fortune 500 aerospace OEM for most of my career. Seeing the differences between the various revisions of "same model" commercial and military aircraft makes your point for you - just because the F-18C/D and F-18E/F look alike DOES NOT mean they are the same from an engineering standpoint! Ditto all the various tweaks of the 747, you can't pull a landing gear from a -100 and use it on a -400.

So I fully understand and respect your point about playing around with a time proven airframe. Further, I have great respect for the "nostalgia factor" associated with a "complete correct" specimen of an older vehicle, be it a classic car or a classic plane. But what I remain uncertain of is whether or not you are attacking the entire STC process in general?

Certainly there are STC modifications that are better than others. For instance, I never liked the "tip tanks" and wouldn't buy a Skymaster with them. But there are also a WHOLE BUNCH of STCs that are just fine.

Just curious where you're drawing the line, here.