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Re: Helicopters C

Posted: May 31st, 2018, 11:22 am
by ScottMaurer19
glouthan wrote:
CrayolaCrayon wrote:I love that three rotor design. I wish I had tried something like that. How did you pull that off (with winding, construction, etc.)?
Construction used the same principles as the 2 rotor as in we needed to keep the rotors on the bottom so the center of mass would be lower (more stability) and of course we had to use some sort of stability vane in order to keep the flight variance down. My thinking process behind this design was that it would be more efficient to use a triangle stabilizer instead of the "X" shaped one with 2 rotors as we could get the weight lower per rotor (3g for 2 rotors = 1.5 g/rotor, but with 3 rotors we could try getting the overall weight down past 4.5g, reducing the weight per rotor). As for the rotors 2 were spinning clockwise and one spins counter clockwise - we never had any issues with this configuration and our flights were stable meaning that even over the approx. 100' height ceiling at state the helicopter would remain only a few horizontal feet from where we launched.

Winding was the tricky part. We eventually started using mini binder clips attached onto the motor sticks to hold the rotors in place so that we could wind the next motor without having to hold the other rotor in place. This was especially helpful when all 3 motors were on as only one of us would have to carry it over to our launch spot then we would we would undo the binder clips and release. It would be difficult moving the 3 rotor device while both of us were holding the rotors - risk of breaking the motor sticks would be high!
Curious as to what flight times you were getting

Re: Helicopters C

Posted: May 31st, 2018, 12:20 pm
by windu34
glouthan wrote:Not sure if anyone is still on these forums but since the 2018 season is over I decided to compile a video showcasing our helicopter designs from the 2018 season, including a TRIPLE ROTOR chinook helicopter! Check out the video to see it!

https://www.youtube.com/watch?v=CTTWWlr ... e=youtu.be
Fantastic job with this! Very interesting to see the triple rotor design

Re: Helicopters C

Posted: May 31st, 2018, 12:58 pm
by glouthan
Windu34 thanks! and ScottMaurer during practice we were seeing times around 3 minutes with the triple rotor on a 9' ceiling but unfortunately we had issues with our motors last minute. We had been using the same ones for all of our competitions since January and were putting more winds on them as the season progressed which helped out times (along with the fact we were trying out new rotors) but unfortunately we snapped them before state so we had to fly on new motors that weren't fully broken in. IIRC we flew the second state flight on 58 winds (which was 3 mins, 2 sec) which is less than the max we could put on the broken in motors ~ 64 winds.

Re: Helicopters C

Posted: June 4th, 2018, 4:45 am
by CrayolaCrayon
glouthan wrote:Windu34 thanks! and ScottMaurer during practice we were seeing times around 3 minutes with the triple rotor on a 9' ceiling but unfortunately we had issues with our motors last minute. We had been using the same ones for all of our competitions since January and were putting more winds on them as the season progressed which helped out times (along with the fact we were trying out new rotors) but unfortunately we snapped them before state so we had to fly on new motors that weren't fully broken in. IIRC we flew the second state flight on 58 winds (which was 3 mins, 2 sec) which is less than the max we could put on the broken in motors ~ 64 winds.
Still, nonetheless, very impressive craftsmanship.

Re: Helicopters C

Posted: June 5th, 2018, 8:45 am
by retired1
Personally, I am amazed at what you were able to do with the design. Lesson for all flyers is to have several pre stretched motors for a significant competition.