24-05-2011, 09:20 PM
Here's some accumulated info I've gathered in building some of my crazy plans.
The attached PDF walks through this (simple) process. It waas written when brushed motors and NiCd batteries were king.
- Calculate the wing loading or desired wing loading.
- Work out approximate horsepower (Watts as input power) needs based on weight for your flying style.
- blah blah blah
- Decide on the prop to get the right amount of thrust and airspeed. The stall speed depends largely on the wing loading and you should aim for a capability of 2-3 times the stall speed.
Since that seems like a bit of a chore, the wizards at RCGroups have got together and built a web page that does just this
.
http://www.rcgroups.com/forums/showthread.php?t=254742&page=2
Of course, motocalc, etc also have valuable databases of stuff but you need to have a ballpark of what you're looking for.
The last (and possibly best) guide is to find others who have successfully flown the same or similar size/weight/dimension models and find out what they used.
If none of that works, try sacrificing your newborn at first light of a full moon with some eye of newt - I think that's still in stock @ hobby king
.
The attached PDF walks through this (simple) process. It waas written when brushed motors and NiCd batteries were king.
- Calculate the wing loading or desired wing loading.
- Work out approximate horsepower (Watts as input power) needs based on weight for your flying style.
- blah blah blah
- Decide on the prop to get the right amount of thrust and airspeed. The stall speed depends largely on the wing loading and you should aim for a capability of 2-3 times the stall speed.
Since that seems like a bit of a chore, the wizards at RCGroups have got together and built a web page that does just this
.http://www.rcgroups.com/forums/showthread.php?t=254742&page=2
Of course, motocalc, etc also have valuable databases of stuff but you need to have a ballpark of what you're looking for.
The last (and possibly best) guide is to find others who have successfully flown the same or similar size/weight/dimension models and find out what they used.
If none of that works, try sacrificing your newborn at first light of a full moon with some eye of newt - I think that's still in stock @ hobby king
.Drew
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Built-up
Balsa: Commercial: Depron:
Great Planes PT-20 (modified) HK Hawk 80 Index 3
Indoor Thingy Skyartec Cessna 182
Katana X lite (in construction) UM SU-26 12"WS Shoestring (Plantraco)
HK Extra 260
and a Fox chuck glider converted to RC
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