Here's my thoughts on turbine conversion of an aircraft designed around a piston
engine. In my opinion it's a process in which one decides they'd rather carry
fuel than passengers and/or luggage. Granted, turbine engines are very sturdy
and deliver all of their horsepower through a wide range of conditions, but at
a
price. If you're going to put one in, get ready to make a lot of compromises.
Let's say I want to regularly cruise in the higher flight levels to take
advantage of the lower fuel consumption rates up there. Now I'm going to need
supplemental oxygen. What am I going to leave behind to compensate for the
weight of an O2 system?
Here's the real kicker, range. Turbines are fuel hogs. A turbine engine isn't
going to run very long on 68 litres of kerosene. So unless I'm only going to
wow the gathering throng at local airshows, I'm in need of more fuel storage.
I
met one gentleman at Sun 'n Fun who had recently converted his fast glass
kitplane into a turboprop. It was at that "90% complete, 50% to go stage", with
no paint and a rather raw interior. I stuck my head in the cockpit and nearly
reeled back from the smell of jet fuel. I asked the pilot what kind of range he
was getting, and he replied "Oh, over a thousand." I didn't ask if he meant
statute, nautical, or metres. I showed some surprise and replied "Wow, how do
you carry enough fuel for that?" He looked at the ground for a moment, then
answered "I've got 2 drop tanks, one under each wing." Interestingly, these
were not attached to the aircraft at that moment. When I then asked what these
additions did to his cruise speed, he waffled, only saying that he did see a 50%
reduction in rate of climb. So as I see it, he's taken a fast, long legged
aircraft and turned it into a slow, kerosene tanker. Another recent example of
this conversion is the Turboprop A-36 Bonanza produced by a company in the
Mid-West. Sales have been glacial. From what I've been told, (Warning! Second
hand facts ahead!) if you load full fuel in this oddity, you can only carry 3
passengers and a change of socks.
IMHO, any attempt to place a turbine engine in an aircraft that was not
originally designed around one is a gross misapplication of ones money and
effort. I see no way one can come out ahead in this area. Now, if you'll
excuse me, I need to get back to my drawing board and finish up my floatplane
mod. for the XS.
Regards,
Steve Genotte
Dallas, Texas
Stephen O'Brien wrote:
> Hello all,
>
> With the Europa's top speed way up at 350Kts, is there anything preventing
> the installation of a small turbo-prop--besides cost?
>
> I heard someone in the U.S. put one in a Lancair to stunning effect, and I
> believe they've survived the experience. Just think what it would do to the
> takeoff run. Might not compare to a JATO, but it'd certainly stun a crowd.
>
> Actually, there is a serious question in here. Just what does prevent the
> development of a small turbine? My guess is that the smaller fan diameter
> would make casting the blades much cheaper (less stresses through
> centripetal force, etc.), but then, my concept of a turbine is limited to
> Encarta animations, and I'm always stunned when I see all the tubes that
> wrap around a real one.
>
> Still, it must be possible to make one from fewer parts than a fuel-injected
> 912, especially if the blades and their rotor could be cast as one piece.
>
> Am I displaying unblievable ignorance here?
>
> Regards,
> Stephen.
> --
> Stephen O'Brien
> Quorum Creative
> Australia
>
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