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This build log entry details construction of the Borjet Maja airframe specifications for which can be found in a previous blog post here.

The Maja was built as per the supplied instruction manual however a few modifications were made to make the airframe more modular.

Firstly carbon fiber mounting plates where made for the elevator and rudder servos so that the in the event of a failure the servos can be quickly replaced.


These mounts were then glued into position on the foam so that the servo could be secured using standard servo mounting hardware.


2-56 Gold-N-Clevises and threaded rod were used in lieu of the kit supplied piano wire for linkages. This allows for a more flexible control linkages system that is not depended on only using one particular size/configuration of servo. Currently Futaba S9257 digital servos are used throughout.


During bench testing it was discovered that the plastic rods that secure the tail/motor section to the main body of the Maja would come loose when the motor was run at high RPM. To overcome this RC car body pins were mounted on either side of the plastic rod.


A 60A speed control(overkill i know) was mounted in the tail section. Note, additional plugs were installed so that the speed control can be replaced without disturbing the main power wiring loom that runs through the plane. This tail section can be entirely removed and replaced with all electronics still intact in under 60 seconds.


For initial testing manual flights will be conducted with no autopilot or sensors on board, thus only the receiver was installed and each of the servo cables were labeled for future reference.


The battery pack was secured using Velcro so its position can be easily adjusted to suit center of gravity requirements.


As there are currently no sensors or additional payloads installed on the Maja the plane was quite tail heavy. Fortunately to balance the plane the Maja's wing position can be adjusted to one of three positions on the fuselage. In this particular case while the plane is quite light the wing was sent to the most aft position.


The Maja was then balanced using the Great Planes CG Machine.


The center of gravity of the Maja occurs at 85mm from the leading edge of the wing.


This concludes build log update 2. Manual flight testing will commence shortly and will be documented in subsequent build progress updates.

Tagged in: Velcro , UAV , S9257 , rudder , Planes , modular , Maja , Machine , Great , Gold-N-Clevises , Futaba , fiber , elevator , CG , carbon , Borjet , autopilot , airframe