My first twin engine model completed & flying
02-02-2006, 11:36 PM
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My first twin engine model completed & flying
Well, it's been nearly 3 1/2 years.........but I finally got my act together. My twin engined aircraft has been built & flown - have to say that the whole process has been very satisfying.
To maximise the chances of success, I "borrowed" an existing design but changed it to suit personal preferences & also the cope physical properties of our flying field. The plane first appeared in an Australian modelling magazine approx 10 years ago so I obtained the plan & changed the following:
Low wing to high wing
Tailplane from top of fuselage to bottom of fuselage
Engine nacelles from on top of wing to under wing - better looks
Undercarriage was attached to wing but moved to under fuselage - increased prop clearance
Compound curved fuselage to basic slab sides - didnt want to invest too much effort in case model was a failure
Slight dihedral to no dihedral - stronger, stiffer wing
Everything else same as plan - ie: wingspan, wing area, tailplane & fin area/dimensions.
Initially, I tried 2 x OS Max 20 engines using 8 x 4 props. Acceleration on the grass runway was brisk but then the plane would not go any faster and had to be "pulled" into the air by use of excessive elevator. Also to maintain airspeed, the engines had to be run at full throttle all the time - not good for the engines, fuel economy or the nerves.
I then switched to OS 25FP's with 9 x 6 props - the character of the plane was immediately transformed. Now I had a model that would accelerate easily to take off speed, practically fly itself off the ground & cruise around at less than half throttle. There is ample power on hand to perform steep climbs, huge loops & the like. I did spend a considerable amount of time (much to the amusement of fellow modellers at the field) getting the engine speeds/settings matched. The time spent was well worth it as I have had 100% engine reliability with now 25 flights on board.
Have uploaded some pics so you can see the finished result. The pics were taken prior to the first flight & so have the OS Max 20's installed.
To maximise the chances of success, I "borrowed" an existing design but changed it to suit personal preferences & also the cope physical properties of our flying field. The plane first appeared in an Australian modelling magazine approx 10 years ago so I obtained the plan & changed the following:
Low wing to high wing
Tailplane from top of fuselage to bottom of fuselage
Engine nacelles from on top of wing to under wing - better looks
Undercarriage was attached to wing but moved to under fuselage - increased prop clearance
Compound curved fuselage to basic slab sides - didnt want to invest too much effort in case model was a failure
Slight dihedral to no dihedral - stronger, stiffer wing
Everything else same as plan - ie: wingspan, wing area, tailplane & fin area/dimensions.
Initially, I tried 2 x OS Max 20 engines using 8 x 4 props. Acceleration on the grass runway was brisk but then the plane would not go any faster and had to be "pulled" into the air by use of excessive elevator. Also to maintain airspeed, the engines had to be run at full throttle all the time - not good for the engines, fuel economy or the nerves.
I then switched to OS 25FP's with 9 x 6 props - the character of the plane was immediately transformed. Now I had a model that would accelerate easily to take off speed, practically fly itself off the ground & cruise around at less than half throttle. There is ample power on hand to perform steep climbs, huge loops & the like. I did spend a considerable amount of time (much to the amusement of fellow modellers at the field) getting the engine speeds/settings matched. The time spent was well worth it as I have had 100% engine reliability with now 25 flights on board.
Have uploaded some pics so you can see the finished result. The pics were taken prior to the first flight & so have the OS Max 20's installed.
02-02-2006, 11:53 PM
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RE: My first twin engine model completed & flying
Looks like a good start into twin engine aircraft.
It appears that it will be one of those that you will actually enjoy flying frequently.
It appears that it will be one of those that you will actually enjoy flying frequently.
02-02-2006, 11:53 PM
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RE: My first twin engine model completed & flying
Bone:
Looks nice, and I like your nose piece. Is it rubber to make the plane bounce in a vertical landing?
Haw.
Glad it has all worked out. Now it's time for a Twin-Air, or maybe a Duellist.
Bill.
Looks nice, and I like your nose piece. Is it rubber to make the plane bounce in a vertical landing?
Haw.
Glad it has all worked out. Now it's time for a Twin-Air, or maybe a Duellist.
Bill.
02-03-2006, 12:11 AM
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RE: My first twin engine model completed & flying
~~~~~~~///// Rudolph da red nose aeroplane //~~~~~
~~~~~~/// had a shiney red noosseee ///~~~~~~
xxxxxxxxx xxxxxxxxx xxxxxxxxx
Bone,, like Gremlin Castle says,,, that is one of those planes you will actually enjoy flying,, and often...
Congrats..
~~~~~~/// had a shiney red noosseee ///~~~~~~
xxxxxxxxx xxxxxxxxx xxxxxxxxx Bone,, like Gremlin Castle says,,, that is one of those planes you will actually enjoy flying,, and often...
Congrats..
02-03-2006, 12:17 AM
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RE: My first twin engine model completed & flying
The nose piece - hard plastic - was the top of my daughter's "Dinosaur Egg" shampoo bottle. Like most things I own, my wife wanted to throw away the empty bottle. Naturally, I resisted her urge and said, "I can use that one day".......... and the rest is history.
