>
>> > > I am 90% done with the airframe of my dragon fly I
>> >
>> > am intending to
>> >
>> > > power it
>> > > with a 13b. Any comments? Anyone seen a rotary
>> >
>> > powered dragonfly?
>> >
>> > > would make
>> > > quite a buzzz.....
>> > > --
>> > > Thanks,
>> > > Brent Hasty
>> > >
>> > > Isn't it a bit heavy Brent?
>> > >
>> > > Paul Lamar
>
> --------------------------------------------------
> vw engines are around 165 lb average see:
> http://www.greatplainsas.com/specsfd.html
>
> I initially began to think about repowering with a rotary when on the list
> someone sent out a link to an outfit making alumininum side plates, this
> makes it around just 50lbs heavier than a vw for well over twice the hp,
> not
> to mention reliability issues...
> What are other means to put a 13b on a diet, if one were willing to
> sacrifice
> a little bit of horse power?
>
> I do not think a rotary powered dragonfly is insurmountable.
>
> ------------------------------------------------
>
>> > I'd think so.. I just about bought a Dragonfly
>> > project, but was
>> > discouraged by the weight limit for an engine, and
>> > who wants to
>> > fly behind a VW motor?.. If memory serves me
>> > correct, a c-85 was
>> > to much weight. A single rotor would fit, but that
>> > might mean a
>> > bit of a wait until they get on the market..
>> >
>> > Jarrett
> --------------------------------------------------------------
> What are the dynamics of aircraft performance that are affected by a
> engine
> weight increase like I am discussing?
>
> Consider the reduction of stall by modifying the Aelerons with a flaperon
> mechanism similar to the kitfox and avid?
> ---------------------------------------------------------------
>
>> I owned and flew a Dragonfly for many years. The 13B
>> is too heavy and powerful for that design.
>
> -------------------------------------------
> How can one ever have too much power?
> -----------------------------------------
>>It was
>> designed around a 1600cc vw, but others have installed
>> c-85/O-200, Jabiru, Subaru, etc, up to about 135hp.
>> Mine was powered by the humble VW for 240 hrs or so,
>> then switched over to a turbocharged Subaru EA81.
>> Performance increased significantly, and no more 50 hr
>> valve jobs req'd.
>
> -------------------------------------------------------------
> At 200lbs the weight of a 13b-aluminum is equal to the ea81 with
> significantly
> more power.
>
> Any clue the VNE of the dragonfly airframe? (cant find it on google)
>
> ------------------------------------------------------------
>
>> There was one fellow out near Mojave somewhere that
>> had built a single-rotor powerplant for the DF. I
>> visited his hangar back in the mid-90's. I have no
>> idea if it ever flew with that engine.
>
> -------------------------------------------------------------
> I have a farm I bought to put a fabricaton shop on that is 2500 feet long,
> I
> hope to be able to get in and out with the dragonfly.
>
> The extra power will help to leap off the ground, but I will have to deal
> with
> a hot landing...... Again the flaperon idea may help.
>
>
>
> Thanks,
> Brent Hasty
Be careful with flapperons. If not done properly you end up with almost
enough flap and not enough aileron control just before touchdown. Is the
Dragon Fly really a rough field bird? If you have to go rotary, then a
single rotor seems the way to go. How were you planning to plumb the
radiator? Midships with an intake?
best
George W
I ran across a wealth of info on the q200 and dragonfly last night in my
research
http://www.imageevent.com/qdf_files
and read the vne paper, servo tabs, reflexes and more...
I was planning on maintaining a improved strip for aircraft.
I am not apposed to a midship radiator but when all approaches finality on the
power plant for this bird I will solidify those decisions.
Brent Hasty
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