Peter,

I never meant to launch a personal attack against you. In my world view,
disagreeing with you does not constitute such, but challenging your
character does. I do not believe that I maligned your character, but if I
did, I apologize and welcome instruction in that which crossed over into
offense.

To clarify: My position on the tailcone belcrank is that it is a better
solution than merely splitting the cables somewhere mid-fuselage. Granted,
ideally the rudder belhorn IS the tailcone belcrank, but that puts all the
connecting goodies out in the airstream (=slowness). Besides, the QAC folks
got it exactly backwards by running the cables FIRST to the tailwheel and
then FORWARD to the rudder. Tailspring breaks and all directional control is
lost.

So, in order of evolution:

1) Use the rudder belcrank as the terminus for the rudder cables, then run
separate cables to the tailwheel. Much better (as you have done). However,
the geometry is not favorable for the tailwheel cables/springs and as I
said, all the slowness leaks out of the fuselage. (Though I do believe that
the lower rudder hinge IS sufficiently robust for such duty.)

2) Put the slowness inside the fuselage where it belongs. But there's the
rub; simply splitting the cables and running one part to the rudder and one
part to the tailwheel invites various minor and major catastrophes, from
rudder flutter to inability to separate the ratios of the control inputs to
each (wheel vs. rudder) to loss of directional control if the tailspring
breaks (yes, it could happen depending on how the whole thing is arranged).

3) A solution to the problems in 2) is to run separate cables all the way
from the rudder pedals to the rudder and tailwheel. Different attach points
on the rudder pedals can accommodate the need for different ratios, the
tailwheel springs can go anywhere, all is good in the world. This might be
the simplest, most austere, most elegant solution available (how come nobody
promotes this one???!)...

HOWEVER,

4) There are people who already HAVE a tailcone belcrank. These people are
in the forefront of defining a pseudo-standard for what constitutes an
acceptable Quickie vis-a-vis the JB6Pack. I've fought good and hard to get
my alignment suggestions recognized as psrt of the 6-Pack because I
recognize that you can never win in a contest against superior marketing
savvy. Not to mention that they are RIGHT (for the most part). Likewise, why
fight success by arguing against the tailcone belcrank. These people HAVE
the belcrank, they BELIEVE in it, and it is part of the GOSPEL of how to
make an acceptable airplane. And it works. You might disagree on engineering
grounds, but the marketing machine is what will eventually lift these planes
out of the dustbin of history and bring the resale value up to something
above sub-par. So what if the solution isn't the most pure one possible? In
fact, that might be an advantage because it is IDENTIFIABLE as so VERY
different from the original. As an engineer you know that there is no
optimum solution, only solutions (PLURAL), so pick one. So long as the
solution has been decreed by the marketing department and is justifiably a
bona fide solution, then allow the engineers to massage it into a more
useful, more elegant, more functional solution than the rudimentary initial
device may have been. What's the harm?

5) These planes were meant to be built by avarage guys with little more than
a high school education. The subtleties of design may escape them, but they
can identify that a part is or is not built in accordance with "the
drawing." Sometimes "complicating" the design actually makes it simpler to
build or just to understand. Sometimes maybe people don't want to dig under
the panel to extract their rudder pedals and get new parts welded to them,
so they find it easier to just add a new belcrank and cut the cables to
suit.

6) Since you don't have a fuselage split, you may not appreciate the
perceived benefit of having the rudder and tailwheel cables all captured
right there in the mouth of the tailcone. It may not actually be a benefit,
but it is perceived as one.

So, Peter, you see, I'm not at all opposed to what you've done or your
opposition to what others are doing. I'm just greatly in favor of some kind
of standardization such as we would have had if a man of Burt Rutan's
stature had been at the helm of the Quickie Aircraft Corporation. Absent
that leadership, I'll take the JB6Pack Cheerleaders Council as defacto
leadership if only through sheer vocal determination (not that they're wide
of the mark, either) in order to establish some sort of recognizable parity
to yank this fine airplane design out of the doldrums of its well-deserved
reputation. There's no reason for the general consensus among homebuilders
to be to sneer at the world's most efficient two seat airplane just because
it lands like snot on sandpaper. Give it a Kleenex and forget the quibbles
over design economy and eloquence. Fix it, put a happy face on it, and make
it friendly again.

As for your Norton, I was only trying to draw a parallel, noting that you
have "abandoned" the elegance of few moving parts and rotary motion in favor
of a well-polished but old-school design with lots of reciprocating bits, in
analogy to the high parts count and "fail point" count of the "un-needed"
belcrank that we continue to try to refine....

As for Jabiru, well, I've spent enough time under their hood already to know
that that little jewel of an engine is being mistreated by the factory
personnel, whoever they are, who are "advising" the design of cowlings for
the various airplanes, including Jabiru's own, that house the sweet little
engines. The plenum design they've recommended is poorly executed, leaks,
and leaves the crankcase soaking in uncirculated cylinder waste heat. If
you've copied anything like the factory cowl on a Jabiru or Thorpedo, then I
think you'll be buying new crankshaft and camshaft bearings sooner than you
should have to. Evidence: the "loosening up" period recommended by the
factory. Evidence: Five minutes at full throttle in a J230 leads to
excessive oil temps in level flight. Evidence: ground operations lead to
high cylinder head temps on #6 under the stock plenums. Evidence: what the
heck are all those cooling outlets for on a Thorpedo??! I won't join the
battle, though, because they have marketing muscle and market penetration on
their side. And I don't have time. But for you, friend, I'll make time to
hint that perhaps you should investigate the possibility that you could be
cooking your expensive investment into scrap aluminum under the factory's
advice.

Cheers, Peter, and carry on. Never mind all this ruckus Stateside.


David J. Gall
P.S. No, I haven't taxied a Q and I don't think I need to. I joined this
discussion because another pilot/engineer had already determined that the
problem existed and had identified the correct solution. His was a question
of implementation. You, however, have questioned the original assertion that
there is even a problem to address. Granted, questioning the assumptions is
what good engineers and armchair quarterbacks do, but all this "diverting
tedious, complex splitting of hairs" has actually been by request. The
necessity thereof was never at issue.