Re: What do your ships look like?

Date sent:  25-JUL-1996 14:37:42 

>Niko writes:

>>  The wings of most modern jet planes (and pracically ALL jet
fighters) 
>> are there to keep the ailerons and flaps further away from the body
of 
>> the plane, and give space for weapon-stoage (look at a Hornet or a 
>> Fishbed. How long do you think they would glide with the engine
turned off?).
>>  It's the engine power that keeps them up there. Of course,
streamlining 
>> is a good idea to keep things from ripping off at high speeds (such
as 
>> might be encountered during re-entry).

>I may not be a jet engineer (I don't even play one on TV) but
>I believe the wings provide a more critical role than you describe.
>Wings translate the horizontal component of thrust from the engine
>into a vertical component called lift. Without wings to provide lift
>planes could not maintain altitude.

Most modern airplanes use the body for a significant proportion of the
lift.

However, if we are talking about very fast jets, the 'wings' are
designed
to create a vortex of air over the wing causing the air above the wing
to move much faster than the air below it. (Note that ordinary wings
just give the air over the wing a longer journey to create the same
effect). The faster moving air has, by definition, a lower pressure. So
the plane goes up. As this method of moving the air over the upper
wing surface is much more efficient than conventional wings, the high
speed wings can be much smaller, so cause less drag.

The snag is that unless the plane is being powered, it can't move fast
enough to create a vortex. No vortices is bad, since the smaller wings
can't hope to create enough lift without them. So below about 200mph
a modern jet has all the flight characteristics of a big brick.

At least thats the way a Concorde works. I presume military jets work
on a similar principle.

>The only other alternative would
>be to fly at a very steep angle of attack, allowing the thrust from the

>engine to provide a force vector in the vertical direction. Such a high
>angle of attack produces excessive drag and is inefficient. Wings are
>the more efficient method for translating thrust to lift.

Hey. You ever seen a Lightening take off? The worlds first VTO
jet fighter (Though it needs a run up to the end of the runway 8-)
)

>Course I look like hell in a body-sock, so there is little incentive
>to beleive me! B-)

Ditto.

>Marty

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