How to calculate lift per rotor at y rpm and x angle?
12-04-2004, 02:24 PM
#1
Junior Member
Thread Starter
Join Date: Nov 2004
Location: Cambridge, UNITED KINGDOM
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
How to calculate lift per rotor at y rpm and x angle?
Hi all,
The son and I are planning to enter the heli guild by building a 1/10 CH-46E Sea Knight. For those not familiar, it's a six blade, twin rotor, twin engine heavy lift/trasport helicopter.
We are a little concerned that we may build a craft to heavy to fly/hover, so have been looking for min/max lift figures for engine speed/angle of attack/rotor combinations but have come up empty.
The questions...
Do you (other bulders) calculate max lift figures before you build?
Where do you get your rotor information?
What rotors (make, supplier, type) would you recomend for 760mm rotors on a heavy craft?
Any help welcome
Thanks
The son and I are planning to enter the heli guild by building a 1/10 CH-46E Sea Knight. For those not familiar, it's a six blade, twin rotor, twin engine heavy lift/trasport helicopter.
We are a little concerned that we may build a craft to heavy to fly/hover, so have been looking for min/max lift figures for engine speed/angle of attack/rotor combinations but have come up empty.
The questions...
Do you (other bulders) calculate max lift figures before you build?
Where do you get your rotor information?
What rotors (make, supplier, type) would you recomend for 760mm rotors on a heavy craft?
Any help welcome
Thanks
12-04-2004, 02:57 PM
#2
Senior Member
Join Date: Apr 2002
Location: ----, NETHERLANDS
Posts: 367
Likes: 0
Received 0 Likes
on
0 Posts
RE: How to calculate lift per rotor at y rpm and x angle?
Hehe good question
I dont think any beginner will know the answer, and not many experts either.
Probably you can get an impression by searching for the frequently popping up questions about how much a heli can lift and checking what are the usual RPM and blade length for those machines.
But 6 rotors!! that's going to be a major construction job. You are going to use 6 engines and 6 governors?
I dont think any beginner will know the answer, and not many experts either.
Probably you can get an impression by searching for the frequently popping up questions about how much a heli can lift and checking what are the usual RPM and blade length for those machines.
But 6 rotors!! that's going to be a major construction job. You are going to use 6 engines and 6 governors?
12-04-2004, 09:08 PM
#4
Senior Member
Join Date: Jul 2003
Location: Morgantown,
WV
Posts: 238
Likes: 0
Received 0 Likes
on
0 Posts
RE: How to calculate lift per rotor at y rpm and x angle?
Sheldon,
If this is your first dip in the heli pool, might I recommend starting with something a little less complex? I think you could learn a lot about the RC helicopter by building and flying a standard RC model. You'd also have a much better chance of successfully flying the CH-46 if you were experienced with single rotor heli's.
That being said; I don't know of a quick and easy way to calculate the lift produced by a certain rpm/pitch combination. The larger single rotor RC heli's flying 700mm blades weigh in at around 10-11 pounds, but fly mostly with headspeeds in excess of 1800rpm ... not very scale-like. A more realistic scale headspeed would still offer plenty of maneuverability. I'd guess that a twin rotor design using similar blades and headspeed would be able to lift twice the weight without any problem. Have you done any weight estimates?
Good luck,
Keith
If this is your first dip in the heli pool, might I recommend starting with something a little less complex? I think you could learn a lot about the RC helicopter by building and flying a standard RC model. You'd also have a much better chance of successfully flying the CH-46 if you were experienced with single rotor heli's.
That being said; I don't know of a quick and easy way to calculate the lift produced by a certain rpm/pitch combination. The larger single rotor RC heli's flying 700mm blades weigh in at around 10-11 pounds, but fly mostly with headspeeds in excess of 1800rpm ... not very scale-like. A more realistic scale headspeed would still offer plenty of maneuverability. I'd guess that a twin rotor design using similar blades and headspeed would be able to lift twice the weight without any problem. Have you done any weight estimates?
Good luck,
Keith
