Carf-Models Ultra Lightning Instruction Manual page 28

Cockpit Tub
A moulded ABS plastic cockpit tub will be included in the
kits. It consists of 4 pieces, which should be joined with plas-
tic cement and painted/trimmed to your choice, in the usual
way. When completed it is glued permanently inside the
cockpit canopy frame. The photo here shows the plain,
unpainted parts, as supplied in the kit.
R/C and Gear Installation
There is lots and lots of space in the cockpit area for your gear layout, and it is a joy to work
on the gear in this model! Everything is easily accessible for installation and maintenance. In
most set-ups the receiver and turbine batteries will need to be installed in the removable nose
section to obtain the correct Centre of Gravity, and you will need to make up balsa supports for
these as needed. Be prepared to install some trimming weight in the nose to obtain the recom-
mended CG, depending on your engine and battery choice. You can also fit the air tank for the
landing gear/brakes in the nose.
Included in the kit is a milled plywood gear mounting plate, and 2 sub-formers that fit under-
neath to secure it. It is a generic plate, designed to suit many different set-ups, and can be
modified as you wish. Once all your gear is set out on the plate, glue the sub-formers in place.
Secure the gear plate to the bulkheads with sheetmetal screws or bolts and T-nuts in plywood
blocks on the sub-formers, as you choose, to make it easily removable for maintenance.
Everyone has their own favourite accessories, methods and options when fitting the R/C and
gear, but the 4 installations shown in the photos can be used as a guide, and have all proven
reliable and easy to maintain and check.
As this is a large model with at least 7 hi-power digital servos we highly recommend that you
install a powerbus system for servo control, and dual Rx batteries, and we can supply the
world famous 'PowerBox' range and their switches. The R/C gear plate has a position specifi-
cally for this item, see photos P49 - P52. If you chose not to use a servo powerbus system, we
definitely recommend that all servo leads and extensions longer than about 30cms (12") are fit-
ted with ceramic chokes (ferrite rings) to prevent RF noise, at the receiver end - within 100mm
(4") of the receiver. Wrap the extension cable through them at least 3 complete turns.
Generally the routing of the air lines, servo extension leads and fuel tubes follows normal prac-
tices. Note that the 5 air-lines to wing, as well as the extension cables for the flap and aileron
servos, all exit through a hole in the side of the fuselage about 50 - 60mm in front of the front
edge of the wing tube. Make sure that you protect these from rubbing against the hole in the
fuselage skin with 'spiral-wrap' or equivalent. Robart 'quick-connectors' for the air lines are
included in the landing gear option pack (photo P48). We have also included enough connec-
tors for the removable nose, in case you wish to install your air tank(s) in there.
Please take care to protect the rudder and elevator servo extension cables from heat, and
make sure that they are secured and cannot touch the exhaust ducting. You can cover the rud-
der cable socket with a scrap balsa plate, and shield the extension cables with aluminium tape
as shown in photo P47.
(above) Plastic cockpit tub dry-
fitted into the cockpit. Add detail-
ing and paint as required.
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