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Weightlifting Competition - Stock C Pack

BATTLEAXE

Well-known member
#21
What if you took a set amount of weight and the competition is to see how far you can go with it before you have to land, 2 laps, 3 laps. That way you can build your plane for efficiency of the lift transfer and not just a heavy lifter.
 

Arcfyre

Well-known member
#22
Wait a minute, Pilgrim, I never said 20 ft span or 70 lbs. That takes at least 50 lbs thrust, probably use @SquirrelTail as the pilot. I do see 20lbs AUW as a max lift possibility on a C pack but that's going to be close to dangerous. I also still think that 1 pound AUW simple scout should win this but that probably won't happen.
I think you misunderstood me. I never meant 20 ft or 70 lb either. It was a simple off the cuff example of what would not work with a c-pack.
 

Duck

Active member
#26
So where did that leave us with the a pack twins? Fair game or nah...
I don't think you can compare one to one. If you call out A-pack twin with your dead weight you should be in that class. I have a little super bee which might lift a few grams.
 

Duck

Active member
#27
I'm about to make a massive foam box and fill it with helium balloons. Then stick on two wings, a cpack motor, and a 20lb weight. I got this one in the bag lol
"Launch under your own power or hand launch. No power assisted launches. Walking to the top of a cliff counts as cheating :p I see you guy in the back thinking of cheating with a balloon launch." - I already cut you off at the pass :)
 

Hondo76251

Well-known member
#28
Just ordered an FT Bushwacker speed kit, with some modification it should be a good contender...

I like the idea of basing the competition on "All up weight" vs Payload as there is no penalty for having things like landing gear (FPV gear, cameras etc)

Doing it this way will make it easier to have a nice looking plane that is competitive vs a flying wing being the only viable option.
 

clolsonus

Active member
#30
Flying wings aren't as efficient as flat bottom airfoils beecause of the reflex
I think you'll also find that in a heavy lift scenario, any kind of stall break will likely be much more violent and hard to arrest in a flying wing compared to a more conventional layout. Most RC'ers are used to light wing loaded (and relatively high power) flying wings -- and they fly great. But when you push the weight and power margins razor thin, flying wings become extremely white knuckle and difficult to launch and land successfully.
 

Hondo76251

Well-known member
#31
My point wasn't a debate on wing design, it was that using the gross weight instead of just payload opens up the option to build an actual model airplane instead of a purpose built lifting contraption.

I realize that I said, "flying wing" but that's not what I had pictured in my mind. I'm not a wing guy so it didn't even dawn on me that it sounds like i meant a versa or kraken. Because the competition is power limited, if we wanted to measure JUST payload you would want to waste as little weight in the airframe as possible. I was picturing something like a storch wing with a carbon fiber arrow shaft for a fuselage and a 4" steel Nut attached under the wing! 🤣 I like where this is going now much better...

Stock c pack
Gross weight
Hand launch or ground roll

Did we settle on a flight time or distance requirement yet?
 

quorneng

Well-known member
#32
Hondo76251
I think you might need something like this. 48" span and 230 g (8.1oz) without the battery
06Feb19.JPG
It normally flies with an 5000mAh 2s which weighs 220 g (8 oz) but with 6 oz of lead substituted along with a 1000 mAh 2s (1.9 oz) it can, and has, flown for 1 hour - 61 minutes to be exact but it was right down to the LVC.
Hand launch and belly land it was built purely to achieve a nominal 5 hours endurance but I am sure its performance could be 'tweeked' a bit to meet specific criteria.
 

Piotrsko

Well-known member
#34
That's where I was going in my early posts. If I put the energy into it, I can easily build something huemongeous that will place in the top. However, that kinda kills the competitive aspect to the challenge for everyone else. I also have this monster A/C unit at my flying site generating huge thermals above 50ft which I can get to on launch.