Conference vmszoo::rc

Re .-1 

BTW, does anybody have any thoughts on feeding some of the spoiler servo output
into the "up" elevator? Would that work effectively to counter some of the nose-
down effect of the spoiler alone? If so, should it be done electronically, in 
the xmtr, the rcvr or mechanically with the servos?

Dave

    The Prodigy was designed by the young prodigy Paul Carlson who used
    to work at Tower Hobbies before branching out and forming his own
    company(Off THE GROUND MODELS).  He is an excellent flyer who placed
    in every category 2-meter, Standard, and open of the NATS all with
    his 2 meter PRODIGY.  The Prodigy uses the Selig 4061 airfoil. 
    I have only seen one fly at a contest last year, it seemed to fly
    quite well.  The building looks a little tricky due to the extremely
    slender fuselage which definitely requires micro servos.  Moving
    from a sophisticated lady to the Prodigy would be a definite step
    up in performance.  High performance 2-meter gliders can be kind
    of tricky to fly because they are so "short coupled".  The full
    flying stab requires very little movement to effect the glider.
    The higher wing loading will mean a faster flying machine than your
    sophisticated lady.  The Prodigy has an excellent track record and
    a good reputation in general.  By the way Paul has a new 100" ship
    out called the QUASOAR, it looks like a scaled up Prodigy.
    
    Jim

    A guy had a Prodigy at the Sudbury glider contest a couple weeks
    ago. The impression he gave me was that it wasn't a good glider
    for a beginner. He said it flew best when trimmed for speed, and
    was tough to handle when trimmed to float. From your description
    of the wing construction, it sounds like it's a pretty rugged design.
    
    About the nose down effect of the spoiler: I thought that was the
    whole idea. It takes the plane down fast without gathering too much
    speed. When doing a spot landing, I bring the plane in much higher
    than normal, then open the spoilers to force a steep descent toward
    the spot. Then flair just before landing. But it still is tricky.
    
    What really amazed me was the big gliders with the flaps. They could
    come down at a remarkably steep angle without gaining speed. It
    looked as if the plane was help up by strings and was being gently
    lowered to the ground. The landing looked more like a dive bombing
    run in slow motion. Very effective.
    
    Dave
    

>BTW, does anybody have any thoughts on feeding some of the spoiler servo output
>into the "up" elevator? Would that work effectively to counter some of the nose-
>down effect of the spoiler alone? If so, should it be done electronically, in 
>the xmtr, the rcvr or mechanically with the servos?

No - don't try to out guess the designer.  If it needed coupling the 
instructions would say so.

Spoilers do not necessarily cause down trim.  They just decrease lift and
speed by spoiling the air over the top of the wing.  And as Dave said - 
it's hard to imagine a case where you want to deploy spoilers and not
come down also.

But if you want to mix it should be done in the transmitter IF the transmitter
can do it.  In that case it is easier to adjust and weights less.

Bye          --+--
Kay R. Fisher  |
---------------O---------------
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RE: < Note 672.1 by OPUS::BUSCH >

    DISCLAIMER:  I am not a glider pilot (yet!) so the following is
    based on "gut feel" and general impressions of talking with glider
    pilots.

    $ set disclaimer=ON
        I agree with .3 and .4 - mixing elevator with spoilers is not
        necessary. 
    $ set disclaimer=OFF

    In general, mixing can be done any of the three ways.  If you choose
    to do it at the Rx, Ace R/C makes a small board that can be added
    between the Rx and 2 servos to mix any amount of either channel to
    the other servo.  I think they call this board the "Christy Mixer"
    or some such thing.
    
    I also agree with Kay; the "best" place to do mixing is in the Tx -
    if you bought one that can do this.  (Or if you are _REALLY_ into
    electronic hacking...)

                       _____
                      |     \
                      |      \                          Silent POWER!
      _        ___________    _________   |            Happy Landings!
     | \      |           |  |         |  |
     |--------|-  SANYO  + ]-|  ASTRO  |--|              - Dan Miner
     |_/      |___________|  |_________|  |
                      |       /           |     " The Earth needs more OZONE,
                      |      /                       not Caster Oil!! "    
                      |_____/

    There seems to be disagreement over whether spoilers should be mixed
    with elevator or used alone.  Actually either method works quite
    well depending on how you intend to fly.  Spoilers perform two
    functions:(1)Decrease lift (2)Increasre drag, hence slowing the
    glider down.  Spoilers deployed alone will usually cause the nose
    of the glider to drop which increases the airspeed.  This is good
    when dethermaling but can be scary when landing, especially if you
    are just beginning.  If spoilers are used in conjunction with up
    elevator the glide angle can be adjusted to a speed you are comfortable
    with.  The spoilers will add a great deal of drag which slows the
    glider, especially when landing into the wind, and the more up elevator
    the less down pitch which also slows the airspeed.  This "dirty"
    high drag configuration dramatically slows down the glider making
    it easier to land for less experienced flyers.  If you are a new
    pilot flying a clean(fast) high wingloading ship, the mixed spoilers
    and elevator might not be a bad idea.  However if you are an
    experienced pilot who can comfortably manipulate two transmitter
    sticks simultaneously the added flexibilty of non-mixed spoilers
    and elevator would probably be preferred.  
    
    
    Jim