Q1_Aircraft: VNE

Hi Martin,

Long time no hear. Firstly, I do not think that it is necessary, The
Q1 is an excellent solution for it's intended mission.

The first port of call would be to look at the Q2 and Q-200 solutions
for the elevator and ailerons. The next task would be to have a good
look at the rudder fin combination. If you had the tools, a flutter
analysis is the best way forward - but it is easier, surely, just to
fly within the envelope. If I wanted a faster aircraft, I would have
built one (oops, come to think about it, I did )

All the above said, that is not to say it cannot be done. I would
rather say that it is unlikely that it can be done simply. It is
simply foolish to assume that everything will be fine because.....
Burt always overdesigns everything right? Guess how much of the
margin was consumed with the VE mainspar issues?

Common sense check : when Burt wanted a faster solution it is
significant that he did not just overpower a Q1 and end up with the
AMSOIL racer...Wonder why?

Regards

John




--- In This email address is being protected from spambots. You need JavaScript enabled to view it. , 'Martin Burns' <martin.burns@...>
wrote:
>
> John,
>
> The Q1 does not have mass balanced control surfaces. Is it worth doing,
> and if so, how would you go about it?
>
> Martin Burns
>
> G-BKSE Q1 Scotland
> (still trying to fit that Kohler engine)
>
> ________________________________
>
> From: This email address is being protected from spambots. You need JavaScript enabled to view it. [mailto: This email address is being protected from spambots. You need JavaScript enabled to view it. ]
> On Behalf Of JohntenHave
> Sent: 06 November 2006 08:46
> To: This email address is being protected from spambots. You need JavaScript enabled to view it.
> Subject: [Q1_Aircraft] Re: VNE
>
>
>
> Sorry Guys,
>
> this is not completely correct.
>
> VNE is determined by the designer and it is the design speed above
> which structural damage or failure can occur if the wrong combination
> of events coincides.E.g. Such things include gust loadings, flutter,
> wing or surface divergence.
>
> THE FACT THAT OTHERS CHOOSE TO UNDERTAKE RISKS THAT THEY EITHER DO NOT
> UNDERSTAND OR DELIBERATELY CHOOSE TO IGNORE WITHOUT ANALYSIS IS NOT
> JUSTIFICATION FOR REPEATING SUCH STUPIDITY. The fact that they got
> away with it once does not guarentee you will get away with it.
>
> Is the quickie overbuilt? Where is the weakest point? What is the
> failure mode? After adding extra weight, how much margin is left?
>
> If you cannot answer those questions before you make the change, do
> not do it.
>
> I agree with Ryan on one point, mass balancing the control surfaces
> will reduce the risk of one of the failure modes due to overspeeding.
>
> John
>
> --- In This email address is being protected from spambots. You need JavaScript enabled to view it.
> <mailto:Q1_Aircraft%40yahoogroups.com> , 'Tri-Q1' wrote:
> >
> > Jonathan,
> >
> > The VNE is a published number set by the designer. This is a speed
> > that a design has been tested to, more speed than that is for the
> > test pilot (YOU) as to what is safe under the conditions it was
> > tested to. A builder that modifies an aircraft or set of plans can
> > change/set the numbers because they are the designer now. The
> > Quickie being a Rutan design is over built , as are all of his, for
> > the mission at hand, why not make it 1 1/2 times as strong and safe
> > as advertised, it protects your bacon and wallet at the same time.
> >
> > I have not compared a set of Q200 plans with the original Quickie
> > plans to see where the extra structural strength is. The simple
> > answer is that all of the moveable surfaces on the Q200 are balanced
> > dynamically. I would bet that Leon knows the answer.
> >
> > Ryan
> >
> > --- In This email address is being protected from spambots. You need JavaScript enabled to view it.
> <mailto:Q1_Aircraft%40yahoogroups.com> , 'jpkuehne' wrote:
> > >
> > > The Vne on the Quickie is 150 mph, I believe, correct? The Q200
> > > must be substantially higher, as I have seen some of them flying
> > > close to 200 mph. What makes the difference? Is there a
> > > substantial change in the way the canard or main wing is
> > > constructed? More layers? Better materials?
> > Bigger/thicker/longer
> > > spar?
> > >
> > > Of course more Hp will be needed, and that means more fuel burn,
> > but
> > > SURELY the frontal surface area of a Q1 is smaller than a Q200...
> > > How much more would it take? (Any engineers out there?)
> > >
> > > So what would it take to build a rocket out of one of these?
> > >
> > > (Not saying I'm GOING to, but just thinking out loud...)
> > >
> > > And BTW - has anyone constructed a larger fuel tank, or added a
> > > secondary tank? How about baggage or fuel pods? I would think a
> > > secondary tank and a hand transfer pump would be a relatively easy
> > > add-on...
> > >
> > > Thanks all!
> > >
> > > Jonathan
> > >
> >
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

All,
So I'm also putting on a larger engine, so the real question is...
should I redline it at 150. If so then I don't need to worry at all?
It would be nice to know the actual design limits. Is flutter the real
risk in the Q, or is it structure?

dave R.
N4YQ
P60 engine soon.
Texas

Hi Dave:
Where in Texas are you located? Have been working on the idea of using
a P-60 engine for sometime.I would like to see your project and exchange ideas &amp;
information. Have a friend also building a high powered quickie who is an
engineer.

R.Glimes

davedrosen < d2r@... > wrote:
All,
So I'm also putting on a larger engine, so the real question is...
should I redline it at 150. If so then I don't need to worry at all?
It would be nice to know the actual design limits. Is flutter the real
risk in the Q, or is it structure?

dave R.
N4YQ
P60 engine soon.
Texas






[Non-text portions of this message have been removed]

Dave,

VNE has nothing to do with power, it is a velocity. Flutter results
in structural failure. It is initiated by a divergent oscillation in a
control surface/ fixed surface assembly (i.e. not mass balanced).
Engine power will not change that, but increased airspeed will.

Increased weight also has an effect, because the G limits are
calculated and tested upon the assumption that the MAW is as per the book.

Next thing to check is that the COG is within the permitted limits
from full fuel to empty fuel for the permitted pilot weight range.
The last thing to do is to check the stressing for the engine
attachments based upon the new engine weight and position. hint -
(forget the superquickie firewall modifications) they are not
correctly engineered.

The design limits are in the book. Change them and you are on your own.

John

--- In This email address is being protected from spambots. You need JavaScript enabled to view it. , 'davedrosen' <d2r@...> wrote:
>
> All,
> So I'm also putting on a larger engine, so the real question is...
> should I redline it at 150. If so then I don't need to worry at all?
> It would be nice to know the actual design limits. Is flutter the real
> risk in the Q, or is it structure?
>
> dave R.
> N4YQ
> P60 engine soon.
> Texas
>