Top Flite Metrick - Manual (Page 13)

PRE-FLIGHT
1. CENTER OF GRAVITY: Although the METRICK has a
fairly wide C.G. range intital flights should be made
with a balance point located directly at the wing spar
location, or 2-5/8" back from the leading edge of the
wing. This is the time to add any ballast required to
achieve this balance point. Ballast should be lead
sheet or lead shot and should be placed forward
and/or beneath the battery pack. The ballast should
be securely but not permanently installed in order to
make changes for personal preference in glide later
on. If you have built the engine powered option it
may be necessary to switch the locations of the
receiver and battery pack to achieve the correct C.G.
2. RADIO AND AIRFRAME INSPECTION: Once again,
check the radio system to be sure that the surfaces
move in the desired direction by radio command and
that the action of the servos is bind-free. If you have
installed a captive tow-hook system, test it's opera-
tion to be absolutely sure of release on command.
Inspect the airframe and it's various components.
Check for warps in all of the surfaces. If any are found,
now is the time to correct them. Initial flights with our
METRICK's employed the use of about 1/4" of wingtip
wash-out (wash-out is the raising of the trailing edge
wingtip). This was used to avoid any tip-stalling ten-
dencies that might have shown up on our prototypes.
Subsequently, our METRICK's have been flown with
and without wash-out with equally good results—
pick the set-up that works best for you. Once every-
thing has been checked to your satisfaction, make
sure the battery pack is charged and head for the
flying site.
FLYING
Whether your METRICK has been set-up powered or
unpowered, you will need to perform a series of hand-
glides to develop a basic neutral trim. Assuming that the
C.G. is right and that the radio is on and functioning, run
into the wind until the airplane begins to feel "light" at
which time throw it straight, slightly nose-down with the
wings level. The airplane should glide straight forward at
a very flat angle. Try to remember what commands you
had to give the transmitter to achieve straight and level
flight. Repeat these hand-glides until you are certain
what is required. We used our transmitter trims to
achieve the flat glide that we were looking for and then
made the required adjustments on the servos, followed
by returning the trims to neutral and repeating the proc-
ess until the plane flew flat and straight with no stick
movement on the transmitter necessary. This then is
dead-neutral trim. As your flight time and familiarity with
the METRICK build-up, you can experiment with moving
the C.G. progressively aft—we caution you to do this in
very small increments—until the point is reached that
you can literally vary the cruise speed of the airplane with
transmitter trim, without stalling. This is done by remov-
ing small amounts of lead ballast from the nose until you
are satisfied.
Assuming that your METRICK is an unpowered sailplane,
the next phase is a tow-launch. Although this method of
launching a sailplane can be intimidating to the beginner,
the METRICK's stability on tow is of great help. If you are
using a "Hi-Start" system—surgical chord and monofili-
ment line—pull the line back until you have about 20 lbs.
of tension. Hook the tow-ring onto the towhook on the
bottom of your model. With the transmitter on and of
course the receiver, hold the airplane in your right hand,
transmitter in your left, with the wings level and the nose
at about 15° to 20° up. Launch the airplane briskly and
level. The airplane should quickly assume about a 50° to
60° climb attitude and be moving in a straight line up and
away from you. Any corrections to maintain the straight
launch should be done with small movements of the
transmitter stick—avoid quick, full-throw movements
because at launch speeds the flight surfaces are very
effective! As the airplane comes over the top of the Hi-
Start, it will begin to slow down and the nose will be
about level with the ground. At this point, apply some
down-elevator to let the tow ring come free from the tow
hook. The airplane should now be free from the tow ring
and flying on it's own. If you followed the hand-gliding
instructions, your METRICK will very likely be very close
to trimmed for flat and level flight.
First try a series of both left and right turns to get the feel
of the rudder, be sure to trim the rudder for straight flight
on the transmitter, if necessary. Next, while at altitude,
slowly feed in up elevator until you observe the airplace
beginning to "mush", this is the beginning of a stall and
knowing where it begins and how drastic it is can save
your airplane later on. Continue to hold up elevator until
the airplace fully stalls—it will literally stop flying.
Observe carefully what it does at this point. Does it lose
all airspeed, drop the nose and continue flying or does it
fall-off on one wingtip or the other? If it falls off on a
wingtip, some washout in the wingtips could help—not
cure—this phenomenon. Practically speaking, it is best to
know the stall characteristics of your particular airplane
and to avoid those flight circumstances which will lead to
them. While we are still at some altitude, try dropping the
nose a little with a touch of down elevator to get some
idea of the speed range that your METRICK provides. As
the model's speed picks up, the airfoil becomes quite
efficient and tends to resist the nose-down condition—
the result is a very flat, fast glide rate that allows you to
cover a lot of territory with a minimal loss of altitude.
Landings, especially some of the first ones, until you are
used to the airplane, should be set-up in the normal
fashion, except for the final up-wind leg which might
have to be longer than you are used to since the
METRICK, with the nose slightly down, as in a landing
approach, tends to want to stay airborne. If you have
equipped your plane with spoilers, the landing task
becomes very easy with incremental amounts of spoiler
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