Date: Thu, 28 Apr 2005 13:34:30 -0400
To: WSFA members <WSFAlist at WSFA.org>
From: "Mike B." <omni at omniphile.com>
Subject: [WSFA] Re: Alternative reality v SF
Reply-To: WSFA members <WSFAlist at WSFA.org>

At 01:02 PM 4/28/05 EDT, MarkLFischer at aol.com wrote:
>In a message dated 4/28/2005 12:47:58 PM Eastern Daylight Time,
>twhite8 at cox.net writes:
>
>>I'm talking about airliners with passengers riding
>>*inside* the  wings (with windows in the leading edges), or a dozen  engines
>>w/propellors mounted on each wing -- pointing *up*.  Ocean  liners of the
>>air....

Flying wings require the use of computers to make them properly stable.
The ones tried by Northrup in the 50s had some serious problems.  The
current ones, such as the B2, work fine.  Passengers in the wings are ok if
you stay low.  If you want to pressurize the passenger compartment (so you
can go above 10,000 feet without oxygen masks) you need it to be spherical
for lightest weight, or the current compromise between weight and capacity:
a round-ended cylinder.  Making them wing-shaped would require too much
mass for reinforcement to hold the shape under pressure, and therefore eat
too much fuel.  I.e. they are inefficient.  The B2 only carries things in
the wings that don't mind low pressures (fuel, weapons, electronics, etc.).

As for planes with vertically mounted propellers, check out the Osprey.
Takes off that way, then rotates the wings to aim the propellers forward
for high speed flight.  You can't go fast with them vertical for the same
reason that helicopters can't go fast:  the retreating and advancing blades
see different relative air flow velocities.  As you increase vehicle speed
eventually one blade will go supersonic while the one on the other side of
the "disk" is well below that, and the turbulence caused results in flutter
and blade failure, and blades don't usually like to go through the sonic
barrier twice on every revolution anyway.  The "X-wing" design is another
way to have both vertical takeoff and high speed level flight...basically
you stop the helicopter blades once you are up and moving, and lock them in
a "X" shape so they act as fixed wings.  Don't know if they've actually
built one of these yet or not.

>I saw that concept dusted off not too many years ago, a huge flying wing
>with facilities to "dock" smaller conventional airliners in the DC-9/727
class
>for passenger, cargo, and fuel transfer.  The plane would fly  an wandering
>circumnavigation course, never landing, handling passengers in  much the
same >way that a city transit bus does today.

If you could make it solar powered, with enough battery to get through the
night, and kept it above the cloud layers at all times, you could keep it
up indefinitely.  Maintenance would be the only issue, and you might be
able to make that happen in flight.  Maybe.  NASA has a plane that uses
this method, but it's unmanned and slow...like a big glider almost, covered
in solar panels.

It might be easier to use lighter than air technology and solar power just
for propulsion, not lift.

There are also the "skyhook" ideas to get planes from one area to another
quickly and with little or no fuel use.  Planes would have to be
space-capable for this to work though, as some of the trip would be spent
outside the atmosphere.

-- Mike B.
--
If you aren't living on the edge, you're taking up too much space.