Michael Jones
Radio Controlled Airplanes


Building the Extra300S

This World Models Extra300S aerobatic plane is similar to my SIG Extra300XS.  It is larger with a 80.5" wing-span but is only about a pound heavier at 14 pounds.  It is a 27% scale model.

Inside the main compartment, there is plenty of room.  The throttle server is a Futaba S3004.  The rudder is rigged with pull-pull cables attached to a Hitec 645MG, hi-torque, metal-gear servo.  The battery is a 1100 mAH connected through an MPI switch and charge jack.   A 24oz. Sullivan tank was used in place of the one that came with the kit.

The receiver is a Futaba R148DF 8-channel radio.  The receiver and battery pack are padded with foam and held in place with Velcro straps.

Looking aft down the inside of the fuselage.  The rudder servo is in front with wires to the rudder horns running to the back.  Everything is built up balsa except the turtle deck and the area in front of the canopy.  They are foam core with balsa sheeting.  

The engine is an OS 1.60FX.  It develops 3.7 hp at 9000 RPM.  I used a predrilled OS motor mount.  The box in front of the firewall had to be assembled.  The kit provided all the wood and tri-stock to attach it to the firewall and two formers.  Everything was glued with epoxy.  The muffler is a Bisson Pitts made specially for the 1.60FX.

The wings are detachable and are held in place with an aluminum rod, a dowel pin, and a threaded rod.  A pre-painted civilian pilot figure was used.  The kit included a different figure.

The completed plane before all of the decals were applied.

The maiden flight was September 1, 2002