5 FLIGHT TESTS NORTHEAST SAILPLANE PRODUCTS ...

NORTHEAST SAILPLANE PRODUCTS ULTIMATE EPP BIPE
The kit's major components are hot-wire-cut
out of EPP foam, and that is a great choice
for an aerobatic model like the Ultimate, as
it can take the abuse. The Kevlar and molded
carbon-fiber landing gear is perfect for
absorbing those less-than-perfect landings.
The outer cabane struts are made of EPP
foam, and the center cabane struts are made
of a fiberglass material to add stiffness and
strength. The kit includes carbon-fiber spars
to stiffen the wings and carbon-fiber rods for
the struts to tie the top and bottom wings
together. The result is a very stiff and very
tough airframe. The kit includes all of the
necessary hardware, and the detailed
instruction manual makes building the
Ultimate an enjoyable task.
PUTTING IT TOGETHER
I started construction by inventorying and
sorting out all of the parts. You'll need a
large work area to lay out complete assemblies
such as the wings and the stabilizer.
>Fuselage The fuselage takes very little time
to complete because most of the work has
already been done for you. The top half of
the fuselage is blue and has a nice tapered
shape to it. The cabane struts are factory
The rudder and elevator servos are installed under
the clear canopy.
installed, and that saves a lot of assembly
time. An EPP hatch covers the battery compartment
at the front of the model, and I
used self-adhesive Velcro* tape to attach it.
Installing the recommended Axi 2212/26
brushless outrunner motor is a snap. Just use
5-minute epoxy to glue the precut composite
firewall to the fuselage. When the epoxy
has cured, use screws to secure the motor to
the firewall and you're ready to move on. To
complete the power package, I used a
Thunder Power 3-cell (11.1V) 1320mAh Lipoly
battery and a Castle Creations Phoenix
25 brushless ESC. Northeast Sailplane
Products provided this recommended drive
system with the review plane, and its website
offers these products as well as a vast
selection of other power systems.
>Wing assembly The Ultimate's two, onepiece,
hot-wire-cut EPP foam airfoiled wings
incorporate flat carbon-fiber spars glued into
recessed areas on the underside of each
wing. The upper and lower wings are slightly
different; you should mark them after
they have been identified so you don't mix
them up. The four ailerons are also wire-cut
and shaped to follow the wing's airfoil.
Before you install the ailerons, thoroughly
clean all of the surfaces. I used denatured
alcohol to remove oil from the areas being
hinged. Listed in the manual, there are several
techniques for attaching the ailerons,
and I elected to use hinge tape made out of
clear, reinforced duct tape. Attaching the
ailerons is simple: just flip the wing upsidedown,
align the surfaces leaving a 1/16-inch
gap and apply the tape to the hinge line.
Temporarily secure the ailerons with masking
tape to prevent them from moving; then
flip the wing over, double-check the aileron
alignment and apply the hinge tape so it's
centered over the hinge gap. Remove the
masking tape, and you've finished.
SPECIFICATIONS
MODEL: Ultimate EPP Bipe
MANUFACTURER: Northeast Sailplane
Products
TYPE: aerobatic electric biplane
WINGSPAN: 31.5 in.
WING AREA: 400 sq. in.
LENGTH: 31 in.
READY-TO-FLY WEIGHT: 14 oz.
WING LOADING: 5 oz./sq. ft.
RADIO REQ'D: 4-channel w/3 microservos
MOTOR REQ'D: brushless
FLIGHT DURATION: 10 to 15 min.
PRICE: $89.95; Axi airplane motor
system, $194.95
COMMENTS
The Ultimate EPP Bipe is a nearly indestructible,
fun-to-fly biplane. Its large
flying surfaces permit it to maneuver
quickly, and its high power-to-weight ratio
allows unlimited vertical performance.
HIGHLIGHTS
>Quick assembly
>Very light airframe
>Strong construction
>Highly aerobatic
The underside of the bottom wing contains the
aileron servo.
The Ultimate has plenty of bracing to prevent the
wings from flexing.