quorneng
Master member
The Frog Wren was a pretty 25" span free flight tissue and balsa kit with twin fins.
This was going to be a powered 3ch version but made entirely in 2mm Depron.
The wings are built up with an upper and lower skin to form a Clarke Y section but with no structural spar, all the load being taken by the skin.
The two servos are glued together to form a block and are mounted just behind the wing.
Mono filament fishing line in a closed loop is used to connect the rudder and elevator.
It weighs almost nothing and it works.
The 7g motor drivies a 5x3 prop.
To start with it had serious stability issues. Initially it had to be rebuilt with a big single fin to get it to fly well enough to sort out all the various problems but eventually it was returned to the original configuration albeit with slightly taller bigger fins and rudders.
The completed Depron Wren.
With a 500mAh 2s it weigh 3.25oz and flies really quite well.
With a minute Hobby King recording altimeter on board I wanted to see just how long it could stay up.
47 minutes 30 seconds
It may have looked like I was using a climb and glide technique but actually its just the difference in power of one 'click' of the throttle stick! The motor was running all the time.
315ft may not sound that high but I can assure you that a 25" white plane against a streaky white sky is pretty hard to see particularly when edge on!
Not bad for a 500mA 2s.
Now can I get it to 1 hour?
This was going to be a powered 3ch version but made entirely in 2mm Depron.
The wings are built up with an upper and lower skin to form a Clarke Y section but with no structural spar, all the load being taken by the skin.
The two servos are glued together to form a block and are mounted just behind the wing.
Mono filament fishing line in a closed loop is used to connect the rudder and elevator.
It weighs almost nothing and it works.
The 7g motor drivies a 5x3 prop.
To start with it had serious stability issues. Initially it had to be rebuilt with a big single fin to get it to fly well enough to sort out all the various problems but eventually it was returned to the original configuration albeit with slightly taller bigger fins and rudders.
The completed Depron Wren.
With a 500mAh 2s it weigh 3.25oz and flies really quite well.
With a minute Hobby King recording altimeter on board I wanted to see just how long it could stay up.
47 minutes 30 seconds
It may have looked like I was using a climb and glide technique but actually its just the difference in power of one 'click' of the throttle stick! The motor was running all the time.
315ft may not sound that high but I can assure you that a 25" white plane against a streaky white sky is pretty hard to see particularly when edge on!
Not bad for a 500mA 2s.
Now can I get it to 1 hour?
