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Description
Text
taken from “Laminar Easy BiP” by Sepp Singhammer in
Fly
& Glide
magazine issue 3/2001.
Translated
by Claudia Lucía Mejía de la Pava
Just
like the rest of the Laminar Easy series, the Laminar Easy 20 or Laminar
BIP (Biposto Italian for ‘two
seater’) has been developed by the World and European Champion Manfred
Ruhmer; sail development has been carried out by Pause Segel.
The
aim was to produce an easy, light handling, overall safe tandem glider
with a decisive improvement in performance regarding the already existing
tandems in the market.
This
glider has been released as a tandem and/or a solo glider for heavier
pilots. In the DHV test the glider achieved a max. take-off weight of 199
kg.
Some
pilots have reported that you do not need to weigh 150 kg in order to fly
the BIP on your own; the
glider weighs 37.6 kg, a 78 kg pilot could fly the glider solo.
Construction
The
BIP is a clear and simple glider. The fastening of the swivel tips is
something to point out: they are fixed by means of a round-headed bolt
that goes into a specially designed fitting, the other end of the tip
passes through a strap attached to the inner upper sail. Once these two
things are done, the tip cannot move sideways nor downwards. This
principle is used in kingpostless gliders too.
It
has a kingpost hang-point to make handling lighter.
There
is a cable running parallel to the crossbar attached to the crossbar/wing
junction on one end and to the central block on the other.
This
cable ensures proper crossbar stability.
The
frame is made out of strong and light
Perunal
aluminum. The inner tubes have a 60 mm diameter and the outer ones 50 mm.
The keel has a 50 mm diameter too and is reinforced in the middle to
account for the extra weight.
The
tubes and fittings are very clean and relying on simple solutions.
As
an option, you may order an asymmetrically shaped speedbar. The curves are
placed so that the pilot, displaced sideways when flying tandem, may still
have a symmetrical grip of the speedbar.
The
wing’s profile height is between average and high because it is
definitely important, for a tandem glider, to have good low speed flying
characteristics.
The
sail has 3 zippers and 2 cloth ribs per side: one zipper by the fiberglass
tip lever, another one at the
rear end of the wing tube (to release the sail for easier short-packing)
and a third one at the crossbar/wing junction. The cloth ribs help
maintain the airfoil when flying at higher speeds.
The
sail has no wrinkles whatsoever: none on the ground and none in flight!
Ground
Handling and Take-Off
During
ground handling you can hardly notice the glider’s weight and, because
of its large sail area, the weight on your shoulders is easily relieved by
a light front wind. Nevertheless this large area also makes it a bit
harder in gusty conditions; in such conditions, it is always advisable to
have 2 good take-off assistants.
“The
take-off characteristics impressed me: With passengers weighing 68 and 74
kg [on different flights] plus
my 84 kg, we climbed at approximately three m/s after three or four steps
in light to moderate front wind, without even sinking a bit!”
Behavior
in Flight
Thermals:
The large sail area offers quite a few advantages when thermalling and in
the overall handling, where less strength is required and the glider’s
response time is shorter.
Another
surprising characteristic is the low speed that you can reach when flying
thermals. “With almost fully
stretched arms, I was able to circle with my passenger in weak
‘bubbly’ thermals, during the fall.”
Straight
Ahead:
The BIP easily maintains its path when flown by an attentive pilot. He/she
just needs to provide the proper steering input in bumpy conditions and
the glider will easily get back into track.
Speed:
The speed range is quite high, Fly & Glide’s test pilot Sepp
Singhammer, reports reaching a max. speed of 90 km/h.
At
higher speeds the bar pressure is light to moderate and the glide is much
better than other tandems.
Cross
country flying is definitely possible with this glider, even though it has
no VG.
Stall:
When stalled the glider sinks at very low values giving a moderate warning
through speedbar pressure. As you let the speedbar go, the glider will
dive in a very gentle way and will recover in a very short time.
Even
if you try to stall the BIP in a harder way, the dive and recovery will
still be gentle.
Stall
speed lies around 32 km/h, depending on your passenger’s weight of
course.
When
stalling the glider in a curve and maintaining your bank angle, the glider
will start to sink but it will easily regain its speed as you pull the bar
in a little. Only when done during circling at higher speeds, will the
stall be ‘harder’.
Landing:
Any pilot who has not a lot of experience doing landing approaches on
tandems must pay extra attention not to over-steer the glider. The more
economically and effectively you fly, the more easygoing your approach
will be.
At
the beginning you should pay attention to your final glides to get used to
the BIP’s performance, because this glider has definitely a better glide
ratio than the other tandems around.
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