Whose airplane is it anyway?

"Richard Riley" wrote

Even 8 is begging for pitch diversion on landing if anything goes
wrong. A little bounce and you're off to the races. It doesn't have
to have that high nose attitude - just a longer, fixed nose gear. A
lot of the gear design is left over from the original design goal of
making it roadable.

Are you sure about that? Are you taking the delta wing's need to come down
nose high, to slow down to reasonable speeds for landing? How about getting
the nose high enough for takeoff? If the nose were much lower, how fast
would you need to go, to get enough elevon effectiveness to lift the nose
for takeoff?

My guess, and forming an opinion from reading flight reports on the Dyke, is
that the unusual attitude is not a problem. While landing, you land nose
high, and the speed becomes whatever is necessary to get a good sink rate.
You don't come down fast, because you won't, if you are too fast. If
anything, a bounce is a non incident, because you mush right back down after
you bounce back into the air.

That is my take, anyway. I would want to fly one, before I went messing
with the landing gear geometry.

I do think fixing the gear is reasonable, though.
--
Jim in NC

Morgans wrote:
"Richard Riley" wrote
Even 8 is begging for pitch diversion on landing if anything goes
wrong. A little bounce and you're off to the races. It doesn't have
to have that high nose attitude - just a longer, fixed nose gear. A
lot of the gear design is left over from the original design goal of
making it roadable.

Are you sure about that? Are you taking the delta wing's need to come down
nose high, to slow down to reasonable speeds for landing? How about getting
the nose high enough for takeoff? If the nose were much lower, how fast
would you need to go, to get enough elevon effectiveness to lift the nose
for takeoff?

My guess, and forming an opinion from reading flight reports on the Dyke, is
that the unusual attitude is not a problem. While landing, you land nose
high, and the speed becomes whatever is necessary to get a good sink rate.
You don't come down fast, because you won't, if you are too fast. If
anything, a bounce is a non incident, because you mush right back down after
you bounce back into the air.

That is my take, anyway. I would want to fly one, before I went messing
with the landing gear geometry.


I have an Xplane model. Not the real thing, but eh...

Even 8 is begging for pitch diversion on landing if anything goes
wrong. A little bounce and you're off to the races. It doesn't have
to have that high nose attitude - just a longer, fixed nose gear. A
lot of the gear design is left over from the original design goal of
making it roadable.

Are you sure about that? Are you taking the delta wing's need to come
down
nose high, to slow down to reasonable speeds for landing? How about
getting
the nose high enough for takeoff? If the nose were much lower, how fast
would you need to go, to get enough elevon effectiveness to lift the
nose
for takeoff?

My guess, and forming an opinion from reading flight reports on the
Dyke, is
that the unusual attitude is not a problem. While landing, you land
nose
high, and the speed becomes whatever is necessary to get a good sink
rate.
You don't come down fast, because you won't, if you are too fast. If
anything, a bounce is a non incident, because you mush right back down
after
you bounce back into the air.

That is my take, anyway. I would want to fly one, before I went messing
with the landing gear geometry.


I have an Xplane model. Not the real thing, but eh...

I don't know the reason, but every delta winged aircraft that I can recall
ever having seen pictured has had a pronounced nose high attitude while at
rest.

From that observation, it is easy to infer reasons--and, of course, to be
wrong!

If anyone here actually knows the real reason, please post it. (Inquiring
minds want to know.)

Peter

Peter Dohm wrote:

I don't know the reason, but every delta winged aircraft that I can recall
ever having seen pictured has had a pronounced nose high attitude while at
rest.

From that observation, it is easy to infer reasons--and, of course, to be
wrong!

If anyone here actually knows the real reason, please post it. (Inquiring
minds want to know.)

Peter



You have to get the nose off the ground if you're going to put a prop
out there.

"Peter Dohm" wrote

I don't know the reason, but every delta winged aircraft that I can recall
ever having seen pictured has had a pronounced nose high attitude while at
rest.

From that observation, it is easy to infer reasons--and, of course, to be
wrong!

If anyone here actually knows the real reason, please post it. (Inquiring
minds want to know.)

Delta wings don't really stall; they go into a "mushing flight" mode. That
is why they can land with the nose way up. To get slow, they need to get
the nose up. Also, the maximum lift coefficients are the highest with a
large angle of attack.

Taking off, the nose high attitude lets it "fly off" the runway when a
decent speed is reached. They would need to go very fast to bring the nose
up from a level attitude, because the elevons are not way back there on a
fuselage with a long moment, like standard wing plan forms. Without the
long moment, the elevons need all the help they can get, initiating
rotation, and the nose high attitude does just that.

You may have noticed that delta wings with a big canard (Mirage,
Eurofighter) do not have such a nose high attitude. The canard provides the
long lever (moment) needed to rotate the wing.
--
Jim in NC

Add to that:

http://www.aerodyn.org/Wings/larw.html

The high alpha is a side effect of low aspect ratio wings.

Richard

"Richard Riley" wrote

Without getting into details, I have enough non-reading-flight-reports
information to be confident about it.

OK, good enough for me.
--
Jim in NC