Airplane design.

Ben Hallert wrote:

Just as a friendly challenge to anyone foolish enough...
Design an airplane within the 254 pound weight limit.


IFR or not? Does it have to be able to fly into known icing?



Ben Hallert
PP-ASEL - http://hallert.net/cozy/


Uh, no.

And day VFR seams more reasonable.
Although I do love flying at night...

Ben Hallert wrote:
Just as a friendly challenge to anyone foolish enough...
Design an airplane within the 254 pound weight limit.

IFR or not? Does it have to be able to fly into known icing?



LOL! Pressurized? Retractable gear?

The only thing stopping me from hanging tricycle gear and a pair of
JetCat 200 turbojets off my Wright machine is the $10k+ cost of the
engines. Supose I could just use a pair of chainsaw motors... or even
6 model airplane engines, but that wouldn't be nearly as cool. By
Wilbur's calcs, the 1902 glider only requires 6 hp at 30 kts cruise.
Stall is at 14, and Vne is about 50 kts. Of course it'll still fly
like crap compared to a modern UL, but then the design is 104 years
old.

Harry

("Richard Lamb" wrote)
Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?


Cri-Cri type
Twin diesels - torque, torque, torque
Wings that rock - "control wing" "free wing"

http://www.flyingflea.org/docs/SprattControlwing.htm

http://www.airandspacemagazine.com/ASM/Mag/Index/1995/DJ/ssfw.html

Original CriCri's weighed approx 150lbs, that included two 9hp engines. 150
lbs - total!

150 lbs - (15# engine + 15# engine) = 120 lbs - 20 lbs other stuff = 100 lbs
of plane building material.

So I'm thinking ...how much would (guessing) 60lbs of Titanium cost?


Montblackium

Montblack wrote:
("Richard Lamb" wrote)

Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?



Cri-Cri type
Twin diesels - torque, torque, torque
Wings that rock - "control wing" "free wing"

http://www.flyingflea.org/docs/SprattControlwing.htm

http://www.airandspacemagazine.com/ASM/Mag/Index/1995/DJ/ssfw.html

Original CriCri's weighed approx 150lbs, that included two 9hp engines.
150 lbs - total!

150 lbs - (15# engine + 15# engine) = 120 lbs - 20 lbs other stuff = 100
lbs of plane building material.

So I'm thinking ...how much would (guessing) 60lbs of Titanium cost?


Montblackium


So, why did they put two engines on that small of of an airplane?
Was it to get around the 61 kts stall speed requirement? (I believe two
engine airplanes don't need to meet that...) Or was it just because they
could?

"Stuart Grey" wrote in message
...
Montblack wrote:
("Richard Lamb" wrote)

Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?



Cri-Cri type
Twin diesels - torque, torque, torque
Wings that rock - "control wing" "free wing"

http://www.flyingflea.org/docs/SprattControlwing.htm

http://www.airandspacemagazine.com/ASM/Mag/Index/1995/DJ/ssfw.html

Original CriCri's weighed approx 150lbs, that included two 9hp engines.
150 lbs - total!

150 lbs - (15# engine + 15# engine) = 120 lbs - 20 lbs other stuff = 100
lbs of plane building material.

So I'm thinking ...how much would (guessing) 60lbs of Titanium cost?


Montblackium


So, why did they put two engines on that small of of an airplane?
Was it to get around the 61 kts stall speed requirement? (I believe two
engine airplanes don't need to meet that...) Or was it just because they
could?

I really don't know either. But it is a pretty old design, so it is
possible that the designed was simply not aware of a suitable single engine
at the time. It is also possible that there was concern about the fuselage
reducing the thrust of a very small prop--the props do operate in relatively
undisturbed air and have plenty of clear space behind them.

To the best of my recollection, the designer really was an aeronautical
engineer--which I am not.

Peter

In article . net, Richard Lamb
says...

Just as a friendly challenge to anyone foolish enough...

Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?

I for one have done it www.cgsaviation.com/hawkultra.htm and so have
others.Mine not also meets the 254 # but the stall speed and top speed criteria
set by the feds in part 103-7. Although I don't think this is the style of plane
the original questioner had in mind. Weight is relative and on this end of the
spectrum alum sheet gets heavy as a build material.Especially if it's over .020.

The Hummel plane is all alum and can carry a 200# guy has a fairly good sized
wing, so it's not a rocket at landing.But it still tips the scales at almost
300# empty.

It's an interesting challenge something us Ultralight guys have had to work with
for about 25 years. One thing I did was to not design to the 170# FAA pilot
since most pilots I know and and those I see at airshows haven't been 170# since
8th grade ,that includes me as well :-)So your design should use 200# -220# for
the design criteria. Good luck.

See ya

Chuck S

ChuckSlusarczyk wrote:
In article . net, Richard Lamb
says...

Just as a friendly challenge to anyone foolish enough...

Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?


I for one have done it www.cgsaviation.com/hawkultra.htm and so have
others.Mine not also meets the 254 # but the stall speed and top speed criteria
set by the feds in part 103-7. Although I don't think this is the style of plane
the original questioner had in mind. Weight is relative and on this end of the
spectrum alum sheet gets heavy as a build material.Especially if it's over .020.

The Hummel plane is all alum and can carry a 200# guy has a fairly good sized
wing, so it's not a rocket at landing.But it still tips the scales at almost
300# empty.

It's an interesting challenge something us Ultralight guys have had to work with
for about 25 years. One thing I did was to not design to the 170# FAA pilot
since most pilots I know and and those I see at airshows haven't been 170# since
8th grade ,that includes me as well :-)So your design should use 200# -220# for
the design criteria. Good luck.

See ya

Chuck S

Hey Chuck,

I've seen those around. There are two or three at Kitty Hawk.
Guess I'll go visit and see how they fly!

Richard

Richard Lamb wrote:
ChuckSlusarczyk wrote:

In article . net,
Richard Lamb
says...

Just as a friendly challenge to anyone foolish enough...

Design an airplane within the 254 pound weight limit.

Clean sheet of paper.
254 pounds empty weight.
Your choice of engines, design, materials.

Where would you start?



I for one have done it www.cgsaviation.com/hawkultra.htm and so have
others.Mine not also meets the 254 # but the stall speed and top speed
criteria
set by the feds in part 103-7. Although I don't think this is the
style of plane
the original questioner had in mind. Weight is relative and on this
end of the
spectrum alum sheet gets heavy as a build material.Especially if it's
over .020.

The Hummel plane is all alum and can carry a 200# guy has a fairly
good sized
wing, so it's not a rocket at landing.But it still tips the scales at
almost
300# empty.

It's an interesting challenge something us Ultralight guys have had to
work with
for about 25 years. One thing I did was to not design to the 170# FAA
pilot
since most pilots I know and and those I see at airshows haven't been
170# since
8th grade ,that includes me as well :-)So your design should use 200#
-220# for
the design criteria. Good luck.

See ya
Chuck S

Hey Chuck,

I've seen those around. There are two or three at Kitty Hawk.
Guess I'll go visit and see how they fly!

Richard


There's a volcanolgist in Iceland that has been flying one over some
pretty dangerous ground for for the past few years. By all accounts it
a good plane but he but have titanium balls to fly any ultralight over a
volcano...