questions on multi-wing planforms

Great link, thanks.
Gerry
"JP" wrote in message
...
They "all" are here.... perhaps not the safest aerial vehicles made?

http://www.aerospaceweb.org/question/design/q0214.shtml

JP


I seem to remember having seen a really short span American design, which
flew in the fifties or sixties. That was in an old issue of "Popular
Mechanics"

Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr

"GTH" wrote in message
...
Hi Gerry,


Thanks for your response, Gilles. A bit of clarification, perhaps. This
is not really a design to fullfill a mission. It's more of a "why not"
exercise.

Understand

The very short wingspan is the only real design criteria, and it
is just my idea rather than a definite need anyone has.

OK. Just out of curiosity, is the short span intended for flight
"requirements" (landing between telephone poles...), or storage
considerations ? Not the same, of course, since for precise landings,
handling qualities may be of prime importance.

Or maybe is it just for the fun of short span ?

That's it. Folding doesn't serve the purpose.
I think the whole thing is inspired by an episode of a tv series call
"galactica" or something of the sort where they had flyable motorcycles.

Gerry


The MCR 01 is a
very interesting design, but with a wingspan of over 20 feet it doesn't
fit my plan. Consider that if you made it a 10 foot span biplane it
would perhaps fit the bill?? I could restate it this way, if you divided
the 20 foot wingspan of the MCR 01 into two wings either tandem or
stacked would it provide similar performance? How about 4 10 foot wings
with one foot chord? I don't really know the answer, I'm just
brainstorming to see if anyone else knows the answer.

I believe that by stacking wings, you'll end up with a much different
airplane.
By the way, really short chord wings work very well, provided the design
is correct.
French aerodynamicist Michel Colomban designed the Cri Cri 10 ft span, 1
ft chord single seater 25 years ago, with really nice flight behavior.
His last project will fly shortly with about 1.5 ft chord.

I seem to remember having seen a really short span American design, which
flew in the fifties or sixties. That was in an old issue of "Popular
Mechanics"

Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr

pTooner wrote:
Firstly, I am new here although I've been reading for a few days. For
anyone with more knowledge than I, I keep considering building a small 4
wing aircraft. Not stacked, but two up front and two in the rear. I have
read frequently of problems supposedly resulting from interference of the
airflow between wings, but I can't seem to find anything very specific. I'm
fairly confident that interference between the front wings (or rear) can be
minimized by reasonable spacing and differing dihedral. I'm not sure what
the effect of the airflow coming off the front wings will have on the rear
set. I don't know whether I could remove most of the problem by having one
set considerably higher (how much?) than the other set or if it is
reasonable to have them on more or less the same height. The reason for
the concept is trying to get a wingspan small enough to fit into a normal
garage and conceivably take off and land from streets and highways. I
visualise something in a two place plane that would fall into something of
the appeal category of a motorcycle or small sports car. Any thoughts would
be appreciated.

Gerry
Hi, Gerry! Just remember this: if you take someone's word that
something won't work, you've only learned to pass that off as fact in
the future, and thus contribute to possible anti-knowledge and myths.
However, if you read as much as you can about a subject, then try it
yourself, even if it doesn't work, you'll know why. Go to www.mbda.net
and click on one of the little symbols in the lower left to get
"search", then put in Diamond back". A very interesting joined-wing,
extendable-wing concept!

ELIPPSE wrote:
pTooner wrote:
Firstly, I am new here although I've been reading for a few days. For
anyone with more knowledge than I, I keep considering building a small 4
wing aircraft. Not stacked, but two up front and two in the rear. I have
read frequently of problems supposedly resulting from interference of the
airflow between wings, but I can't seem to find anything very specific. I'm
fairly confident that interference between the front wings (or rear) can be
minimized by reasonable spacing and differing dihedral. I'm not sure what
the effect of the airflow coming off the front wings will have on the rear
set. I don't know whether I could remove most of the problem by having one
set considerably higher (how much?) than the other set or if it is
reasonable to have them on more or less the same height. The reason for
the concept is trying to get a wingspan small enough to fit into a normal
garage and conceivably take off and land from streets and highways. I
visualise something in a two place plane that would fall into something of
the appeal category of a motorcycle or small sports car. Any thoughts would
be appreciated.

Gerry
Hi, Gerry! Just remember this: if you take someone's word that
something won't work, you've only learned to pass that off as fact in
the future, and thus contribute to possible anti-knowledge and myths.
However, if you read as much as you can about a subject, then try it
yourself, even if it doesn't work, you'll know why. Go to www.mbda.net
and click on one of the little symbols in the lower left to get
"search", then put in Diamond back". A very interesting joined-wing,
extendable-wing concept!

Gerry,
Try NASA CR-178163 'Weight estimation techniques for composite
airplanes in general aviation industry'. Published 1986. While the title
says that it is for weight estimation, the report goes into pretty great
detail about various wing configurations, straight, canard, biplane/dual
wing, and swept forward/rearward and joined wing. In fact, it is the
first report that I can recall ever seeing that did any actual analysis
on joined wings. Lots of graphs showing the relative performance of
differing staggers and separations. Sounds like it's just what you are
looking for.

Morgans wrote:

"flybynightkarmarepair" wrote


This is an admittedly arbitrary distinction. The cabin on a Dyke Delta
is, again, IMHO, not well integrated into the fuselage/wing - MY
definition of a lifting body is that it's ALL an integrated whole.


So, in your opinion, the Hyper Bipe is not a lifting body? It provides
substantial lift, therefore, it is a lifting body, in everyone's view,
except yours.

I submit that you are incorrect.

Well, so does the Tailwind.

But the trick is, alla these have - well - wings!

Stall speeds???

I believe that these aircrafts are the ones having the Vso and Vne far too
close to each other :-)

I would be more worried about the actual glide ratio that may beat even the
space shuttle and that's scary. An engine out landing flare might be an
experience of a life time?

JP


"cavelamb" wrote in
message
JP wrote:

They "all" are here.... perhaps not the safest aerial vehicles made?

http://www.aerospaceweb.org/question/design/q0214.shtml

JP

Far Out, JP.

But they didn't show weights or stall speeds...

"ELIPPSE" wrote in message
ups.com...

pTooner wrote:
Firstly, I am new here although I've been reading for a few days. For
anyone with more knowledge than I, I keep considering building a small 4
wing aircraft. Not stacked, but two up front and two in the rear. I
have
read frequently of problems supposedly resulting from interference of the
airflow between wings, but I can't seem to find anything very specific.
I'm
fairly confident that interference between the front wings (or rear) can
be
minimized by reasonable spacing and differing dihedral. I'm not sure
what
the effect of the airflow coming off the front wings will have on the
rear
set. I don't know whether I could remove most of the problem by having
one
set considerably higher (how much?) than the other set or if it is
reasonable to have them on more or less the same height. The reason for
the concept is trying to get a wingspan small enough to fit into a normal
garage and conceivably take off and land from streets and highways. I
visualise something in a two place plane that would fall into something
of
the appeal category of a motorcycle or small sports car. Any thoughts
would
be appreciated.

Gerry
Hi, Gerry! Just remember this: if you take someone's word that
something won't work, you've only learned to pass that off as fact in
the future, and thus contribute to possible anti-knowledge and myths.
However, if you read as much as you can about a subject, then try it
yourself, even if it doesn't work, you'll know why. Go to www.mbda.net
and click on one of the little symbols in the lower left to get
"search", then put in Diamond back". A very interesting joined-wing,
extendable-wing concept!


Very interesting, thanks.
Gerry