One idea that comes to mind is the method that Burt Rutan uses on his
Long-EZ aircraft. At the wing tips, he has rudders. These rudders
work in a very particular way. If you press on the left rudder pedal,
only the left rudder works, by swinging outboard. If you press the
right rudder pedal, only the right rudder works, by swinging
outboard. However, if you press both rudder pedals at the same time,
both rudders swing outboard at the same time, and act as an air brake
system. It is a very clever design and could be used effectively on a
high speed, low level flying WIG.
On Mar 24, 1:53 pm, Ken Roberts <for...@[EMAIL PROTECTED]
> wrote:
> On Mar 24, 3:29 pm, Buy_Sell <werksp...@[EMAIL PROTECTED]
> wrote:
>
> > The big attraction to the WIG concept, is speed and fuel efficiency
> > over water. My next question is about, how would you perform an
> > emergency stop is a WIG? and what would be a reasonable theoretical
> > stopping distance if you were traveling at say 100 mph as an
> > example?
>
> > I realize that this depends on the design, etc, etc. But in theory,
> > how would you go about getting a WIG stopped in a real hurry? With
> > your hovercraft, you stated before that you spin it around 180 degrees
> > and go full throttle in the opposite direction. I am not sure that
> > this could be done in ground effect, so aside from a parachute, what
> > are the options?
>
> I haven't even worked that out myself yet. I made a UH-18sp, haven't
> yet seriously pondered wings yet although I will almost certainly do
> it when I get the chance.
>
> With regards to the UH-18sp, which is the only truly functional full-
> sized WIG I've seen yet firsthand for more than a few minutes
> operation time, first thing is it isn't fast. The ones I've seen took
> off somewhere between 45 and 60 mph, and they don't fly much faster
> than that. WIG or not, they're fully functional UH-18sp's which means
> they have excellent plow characteristics. The times I've seen one of
> the UH guys stop fast, they just slam it down on the water and stop
> like it's a hovercraft. The other option is to bank it hard to avoid
> the obstacle, which is probably faster than stopping if you have
> someplace to go.
>
> The UH-18spw flies considerably nose-up. It can't dive into the water
> nose first based on that angle. If you push the stick all the way
> forward from full height, you still land tail first, or so I've been
> told. I've never flown the WIG version, although I've driven a couple
> long tail versions as hovers without wings.
>
> I've cruised alongside UH-18spw's lots of times, including when the
> wing rib broke and once with a wooden spar that broke, and a torn wing
> fabric. While breakage causes a relatively hard landing and sometimes
> a hard turn to one direction or another, I haven't seen a hardware
> failure cause an accident yet. I've seen video where Bill took it out
> in too high a wind and cartwheeled it when hit by a gust, but that's
> as much an operational problem as a technical one, and nothing was
> damaged (including Bill). Obviously, Something Real Bad could happen
> in such a situation, but it's not automatically disastrous.
>
> IMO, the reason the UH-18spw is so forgiving is that it's not a very
> good WIG. A "good" WIG would fly level, so if it had any altitude it
> would be able to nose in and do real damage on a hard landing. It
> doesn't fly fast, so at any point the craft will not see a speed for
> which the plow planes are inadequate.
>
> The WIG in the video flies lower than the UH-18spw. It flies inches
> rather than feet off the water, so that probably makes up for the lack
> of a significant nose-up attitude. Still, you should be able to nose
> it in or drop thrust and land just like a boat. That craft does not
> do fast turns on the water though, it's more a "point and squirt" type
> machine.
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