Contest airbrake, Order No. 72 2645
Length 250 mm, installed height 16 mm
For models of about 2.60 to 3.60 m wingspan
Contest airbrake, Order No. 72 2646
Length 370 mm, installed height 16 mm
For models of about 3.20 to 4.60 m wingspan
There are often problems with conventional airbrakes -
especially the longer versions. They tend not to open or
close reliably, or get „sucked out“ at high airspeeds
because they are only latched at one end. The central
locking system * of MULTIPLEX Contest airbrakes solves
these problems one hundred percent. The outer brake
blades feature a central latch and an over-centre lock, so
the brake retracts smoothly every time and cannot be
sucked out at high speed.
-
Central locking - the airbrake closes reliably.
-
Can be dismantled completely even when installed.
-
Internal actuation - very helpful if the airbrake is to be
installed under the wing skin.
-
If necessary the unit can be converted to side actuation.
-
All parts can be removed and replaced even when the
brake is installed.
* 370 mm version only
Please note:
When the airbrake is assembled and closed you may
find that you cannot open it from outside because
the latch has engaged. If this should happen on no
account force the blades open as this will inevitably
damage them.
Just tap the airbrake a few times on a firm surface as
shown in Fig. 1, and this will disengage the latch. You will
now find that the brake blades can be lifted out of the box
easily if you work carefully.
Dismantling assembled airbrake units
The airbrake blades, levers and actuating arm can all be
removed from the airbrake box. This is often necessary if
you are installing the brake box under the wing skin, and
it is also useful when you want to replace damaged or
worn parts.
1. When the airbrake is extended the
top blade
can be
lifted off upwards.
2. The
bottom blade
can be disengaged by pressing on
its retaining point with a fingernail and pushing in the
opposite direction. It can then be removed.
3. The
levers
can now be disengaged from their pivot
shafts by gripping them with a pair of pliers and carefully
twisting them off sideways.
[
Contest airbrakes
Fig. 1
Fig. 2
Fig. 3
The lever and actuating mechanism of the left-hand
airbrake can only be removed from the guide block if the
plastic lever is laid horizontal after disengaging it from
the pivot shaft.
This does not apply to the right-hand airbrake - the lever
can be in any position.
Assembling the airbrake units
1. Left-hand airbrake unit: the lever and actuating
mechanism can only be slid into the guide block if the
plastic lever is held horizontal. Position the hole in the
plastic lever over the pivot shaft and press down from
above using a screwdriver or similar tool to engage it.
Right-hand airbrake unit: the lever can be in any position.
Slide the lever and actuating mechanism into the guide
block and hold the plastic lever vertical. Hold the lever in
a pair of pliers and fit the hole in the lever on the pivot
shaft.
2. Hold the levers erect and press the
bottom blade
onto
the retaining lugs. The angled end of the blade must face
the end of the box with the actuator.
3. Hold the levers erect, position the
top blade
on the
pivot points and press down with your fingers. The angled
end of the blade must again face the end of the box with
the actuator.
4. Check that the airbrake works smoothly and freely.
Completing the linkage to the Contest airbrakes
The linkage to the Contest airbrake is connected inside
the airbrake box. Once the blades are removed the
pushrod is freely accessible.
Solder a threaded coupler onto one end of a 1.3 mm Ø
steel pushrod and screw a clevis on the coupler. Install a
bowden cable outer in the wing running from the airbrake
to the servo output arm. Push the end of the bowden cable
outer into the hole in the end of the airbrake box and secure
it with a drop of cyano. Install the pushrod and connect
the clevis to the actuating lever inside the airbrake box.
Connect the pushrod at the servo end, fit the airbrake
blades and check that the system works correctly.
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
