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[Courtesy of Joel Foner joel.foner "at" fonerassoc.com,
Here are some shots of the Mantis, a new open class sailplane designed by Tom Kiesling.
The pair of ships in these pictures are owned by Anker Berg-Sonne (anker "at" ultranet.com) and John Nilsson (nilssonj "at" rd.simplexnet.com). There are a
bunch of interesting features in this design - hopefully the shots below show off many of
Information about the Mantis,
including ordering information, is available at http://home.att.net/~CASA/Mantis/.
Here are Anker and John with a pair of "Manti" (!?)
And here's one up in the air...
Click on each of the small thumbnail images below to see a full-size picture
Here is Anker's a bit closer up
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A distinctive feature of the Mantis is the pylon-mounted wing. This approach cleans up the
aerodynamics by minimizing the disturbance to airflow at the root of the wing. It
also allows the flat center section to have a one-piece, very effective flap.
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The bottom of the pylon is also very clean. The fuselage is a single tube, that runs
from the "nose bump" all the way to the tail. Rather than add nose weight,
the tube is a bit over length - that way you can make the nose length just right for
balance without adding length. A neat idea!
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This picture shows the pylon with the wing removed. Note the arrow for which way is
forward. Another interesting design concept is the built-in ballast area.
There are three cylindrical holes in the pylon. Without any ballast, the two ships
shown here are under 60 oz.
By putting cylinders of ballast (brass tube with lead
in it) in the three ballast tubes, you can add over 20 oz of ballast, in increments
appropriate for the day.
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Here is the bottom of the wing center section. Note the one-piece flap, and the
outline of the reinforcement that mounts to the pylon.
Oh, another neat idea - the wing
attaches with one bolt! This provides an attachment that is very
secure, since the bolt goes down to the bottom of the pylon, yet allows the wing to pivot
if you catch a tip, helping to prevent "torn wings" on a rough landing.
The wing tip is a plug-in design with a CF joiner rod.
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The radio area doesn't leave much space to fool around in. It's basically just
big enough for a 500 mAH pack in the nose, with a pair of HS80 metal geared servos behind,
and that's it! This is Anker's Mantis, with the "stock" pushrod
installation. Note the nose cone with the pronounced tooth.
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John decided that he just had to have pull-pull. After some fussing, he found a way
to get both servos, pull-pull rig, adjusters, and enough arm length for reasonable throw
to fit inside the nose.
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Another shot of the skeg. There is no question about whether or not the plane will
stop when this touches the ground.
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Here is a landing sequence... One trick the Mantis does real well is full flap, full
down, and it just comes down at 45 degrees - without picking enough speed to matter at
all. Just like a parachute, but with full control.
This one is a big shot, but I couldn't bring myself to crop out the clouds...
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Getting ready to hit the spot