Originally Posted by
SecondLife
I have a Seneca II and considering using it for flight training. I know the conventional wisdom (mentioned here and that I have repeated myself) that having turbos on a training aircraft is a bad idea. I wonder though if anyone has practical experience with this? For example, would one expect the turbos' life expectancy to be cut in half? Or worse?
One bad thing with turbos is rapid power reductions where you have a fast spinning turbo with reduced oil pressure. You can't just yank an engine on climb out but otherwise I'm not sure how the turbos would be stressed by typical training scenarios. Granted its been a few years since I taught ME students so I may be missing something.
In some regards the Seneca II is not a bad twin for ME training. It has great performance when lightly loaded so it would keep a student on his/her toes. It also has a good single-engine service ceiling (12,000 ft) so you can actually do some flying on one engine.
The only turbocharger failures that we've experienced haven't been of the catastrophic type.....the turbine blades, if cooled too quickly, evidently get brittle and eventually a small piece of one of the blades will break off, causing the turbocharger to vibrate and eventually break off of it's mounts.
We run 8 Seneca IIs, and I've had many failures, but what I've described above is the only type of direct turbocharger failure that we've experienced.
The turbocharger, however, creates many more "indirect" problems, some of which are described in my first post on this thread.