dropmaster
Aerospace
- Jun 2, 2003
- 4
Background:
I'm the Director of Engineering of DropMaster, Inc. My patented invention, CopterBox, can be seen at:
Also please see the 'Why CopterBox' link on the home page:
There is a video, some articles and a white paper.
This information is provided for background purposes only and not for selling, as we only sell to government agencies due to liability concerns.
The Army (Natick Labs) has come to us asking for a 500 lb payload version, which I'm calling MonsterBox (the current CopterBox is designed for 60 lbs but will actually handle 100 lbs) and I have some ideas about how to increase lift. CopterBox has patented, faceted, cardboard rotor blades. MonsterBox will likely have extruded foam rotor blades with a more efficient airfoil. My main question is this:
CopterBox has always had 3 rotor blades. We can now add more, but have never really flown with 4 or 6 blades. I'm wanting MonsterBox to have 6 blades and I'm looking at innovative ways to increase lift. My primary interest is the effectiveness of (3) blades having -6 degree pitch like Copterbox (to initiate rotation) but the other alternating (3) blades having 0 degrees of pitch, which will at first not have any forward thrust but hopefully will drive the blades forward once maximum RPM has been achieved and the velocity triangles have had a chance to catch up. The (3) blades with 0 degrees of pitch will provide more lift (and drag) than the -6 degree pitch blades. There can be some vertical separation of alternating blades in case there is some adverse cascading effect. Is this approach a valid one to consider for significantly increasing lift? Another approach is to reverse rotor pitch prior to ground contact, but I'm trying to keep this simple and low-cost.
Does anyone have any input or know of someone who can help?
Thanks!
Chase
I'm the Director of Engineering of DropMaster, Inc. My patented invention, CopterBox, can be seen at:
Also please see the 'Why CopterBox' link on the home page:
There is a video, some articles and a white paper.
This information is provided for background purposes only and not for selling, as we only sell to government agencies due to liability concerns.
The Army (Natick Labs) has come to us asking for a 500 lb payload version, which I'm calling MonsterBox (the current CopterBox is designed for 60 lbs but will actually handle 100 lbs) and I have some ideas about how to increase lift. CopterBox has patented, faceted, cardboard rotor blades. MonsterBox will likely have extruded foam rotor blades with a more efficient airfoil. My main question is this:
CopterBox has always had 3 rotor blades. We can now add more, but have never really flown with 4 or 6 blades. I'm wanting MonsterBox to have 6 blades and I'm looking at innovative ways to increase lift. My primary interest is the effectiveness of (3) blades having -6 degree pitch like Copterbox (to initiate rotation) but the other alternating (3) blades having 0 degrees of pitch, which will at first not have any forward thrust but hopefully will drive the blades forward once maximum RPM has been achieved and the velocity triangles have had a chance to catch up. The (3) blades with 0 degrees of pitch will provide more lift (and drag) than the -6 degree pitch blades. There can be some vertical separation of alternating blades in case there is some adverse cascading effect. Is this approach a valid one to consider for significantly increasing lift? Another approach is to reverse rotor pitch prior to ground contact, but I'm trying to keep this simple and low-cost.
Does anyone have any input or know of someone who can help?
Thanks!
Chase