Carf-Models Ultra Lightning Instruction Manual page 12

the door opening for additional stiffening if you wish.
Finally secure the 1" stroke BVM door cylinder to the milled
plywood sub-former supplied, (photo P6) and route the
tubes to suit your retract and door system valve.
Alternative Dual Nose Doors
As with all jet models, the nosewheel tends to throw up
debris into the cockpit and R/C bay - which is especially
dangerous on a damp runway. For this reason it is prefer-
able to install dual nose gear doors, with the main (rear)
door on a door sequencer so that it closes again after the
gear has been extended - preventing 99% of this problem.
This can easily be done by cutting 85mm off the front of
the supplied door, and hinging it at the front either with 'off-
set' door hinges, or a pair of flat plastic hinges as supplied
for the wing outer doors.
Actuation of the front door is simple, using a small plywood
block on the door and a cable tie around the noseleg -
length adjusted for correct closing. The remaining back
part of the door is installed exactly as described above,
using 3 of the phenolic hinges and door cyclinder. Note that the front door has a small lip on
the back edge, made from the thin fibreglass strip supplied, to provide a closure for the back
door when closed.
Nose Section
The removable nose section is totally completed for you at the factory. With it (and the exhaust
and tailcone) removed the plane is just 2 metres long and will fit in even a standard station
wagon car, or a small box for shipping (photos P7 and P8).
It is held in place by 3 specially designed aluminium dowels that locate in plywood formers,
and retained by three M4 x 50mm long allen bolts (with a washer under the head) that go thru'
the front nosegear former. It is easiest to use a ball-ended allen key to tighten the 3 bolts from
inside the fuselage. If you remove the nose regularly, for transport, then you can make sure
the 3 bolts don't get lost by adding a small 'O' ring or length of silicone tube over the bolts.
Engine and Ducting Installation
Turbine installation (& maintenance) is very simple with
easy access thru' the large bottom hatch. It is a fully-
bypassed set-up, using the new carbon composite bypass
duct supplied. We recommend a turbine of 15 - 16kg thrust
(eg: Jetcat Titan or P160, AMT Pegasus HP etc.) which
give more than enough power for great performance and
an easy Centre of Gravity position with the gear in the rec-
ommended positions. However, the bypass is 150mm
diameter, which does also permit installation of larger tur-
bines like the JetCat P200 or AMT NL Olympus HP.
(above and below) A nice neat
example of dual nose gear doors
from Peter Agnew (Intairco), using
offset door hinges.
(above) The carbon bypass duct-
ing is trimmed in the factory, and
the 3 rear fixings for the upper
half are already completed.
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