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Author Topic: Anybody coached, or competed in, the Science Olympiad "Helicopters" event?  (Read 1301 times)
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lincoln
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« Reply #25 on: March 22, 2021, 10:16:56 PM »

I'm kind of surprised that the helicopters with sheet balsa blades are overweight.  If a 12 inch(30.5 cm), sheet balsa pennyplane prop can weigh 0.65 grams, I don't see why a 20 cm sheet balsa prop can't be 0.4 grams or even less. What am I missing? Is everyone required to use wood from 1970's Guillow kits? At least for me, a sheet blade would probably be easier to make than a built up one, even with camber.

Hypothetically, if a two axis heli can be made to the minimum weight, and stability issues can be addressed, it should have better efficiency.

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bjt4888
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« Reply #26 on: March 23, 2021, 01:52:34 PM »

As a good flying Heli is launched with a relatively high motor torque, it is best to commit a significant share of the 2.5 gram weight budget to the fuselage. This leads to the need for light (but strong) built up rotors. Our rotor a are .020” carbon rod LE and TE and are quite light. A good balsa fuselage is still quite light and will only take high torque if reinforced by Kevlar truss thread. My students are flying the equiv of the 2016-17 national championship times, so the design concept in my earlier posts is working well.

Brian T
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Little-Acorn
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« Reply #27 on: April 10, 2021, 08:24:19 PM »

For SoCal State competition (all virtual), They had the competition last Saturday. My school's helicopter team had a top flight of 1 min 28 sec. There were 30 schools on Category C (high schools).

Today (April 10) was the Awards Ceremony, finally. My school (Westview) came in 11th overall. 27 high schools had Helicopter teams. My Heli team came in 8th.

Congrats to the kids, they were VERY dedicated, did a fair amount of experimenting and thinking, and it paid off.

I HATED doing this "virtually", by Zoom. Only good thing I can say is that all the other schools had to do it too. I still have never met most of the kids on my own Helicopter team, unless they were in one of my previous fixed-wing classes (Wright Stuff, Electric Wright Stuff, Elastic Launched Gliders). Frustrating.

But we got it done.
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bjt4888
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« Reply #28 on: April 12, 2021, 01:57:59 PM »

LA,

Great job to you and your students.

Brian T
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