Flight B/C

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Flight B/C

Post by bernard »

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Re: Flight B/C

Post by pumptato-cat »

Hey, I have a couple of questions.
1) What ratio rubber winder would you guys recommend? I read somewhere that larger ratios like 15:1 are better for thinner rubber, and 10:1 or smaller is better for thicker rubber. Is this true?
2) how do you compensate for AC while flying? Last year in NC states I watched a bunch of teams struggle to get 1 minute flights(AC was so strong) and they were all nosediving/stalling. advice?
3) Where do you guys get torque meters? I want to buy one but they all seem very expensive or have crazy shipping rates.... is building one better?
4) How much do you guys spend on this event in an average season as a competitive team?
(i'm looking at buying J&H right now but shipping is crazy. This seems like the best option though, as FF has not released yet and I'm new to Flight. with shipping, 2 planes = 80$, torque meter = ~20$, winder = ~20$, and that's not counting lubricant/spray adhesive/other materials. Am I doing something wrong, or is this a normal amount of money to spend? (we're self funded, i'm trying to budget)
5) Do kits really make a huge difference in flight time? (like, if I buy a kit with estimated flight time 2min, is that the highest i'm going to get?)

(sorry if these have already been answered-I have looked through multiple years of forum posts, and they haven't helped answer some of my questions though...)
Last edited by pumptato-cat on October 2nd, 2022, 10:57 am, edited 1 time in total.
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Re: Flight B/C

Post by bjt4888 »

pumptato-cat wrote: October 2nd, 2022, 10:55 am Hey, I have a couple of questions.
1) What ratio rubber winder would you guys recommend? I read somewhere that larger ratios like 15:1 are better for thinner rubber, and 10:1 or smaller is better for thicker rubber. Is this true?
2) how do you compensate for AC while flying? Last year in NC states I watched a bunch of teams struggle to get 1 minute flights(AC was so strong) and they were all nosediving/stalling. advice?
3) Where do you guys get torque meters? I want to buy one but they all seem very expensive or have crazy shipping rates.... is building one better?
4) How much do you guys spend on this event in an average season as a competitive team?
(i'm looking at buying J&H right now but shipping is crazy. This seems like the best option though, as FF has not released yet and I'm new to Flight. with shipping, 2 planes = 80$, torque meter = ~20$, winder = ~20$, and that's not counting lubricant/spray adhesive/other materials. Am I doing something wrong, or is this a normal amount of money to spend? (we're self funded, i'm trying to budget)
5) Do kits really make a huge difference in flight time? (like, if I buy a kit with estimated flight time 2min, is that the highest i'm going to get?)

(sorry if these have already been answered-I have looked through multiple years of forum posts, and they haven't helped answer some of my questions though...)
Cat,
1. 15:1
2. Very important to have air handlers turned off for flight testing and competitions. I coach four schools in mid-Michigan and have worked carefully with the school administrators to be sure that the blowers are off. It takes perseverance and lots of communication to teach the schools the importance of this factor and get it done. If you have to fly with blowers on, try to fly late in the day so that you can observe other's flights and determine the bad areas and the drift directions. Then fly according to the drift. You might have to launch somewhere other that the middle of the gym to get the best air. Also, you may need extra launch torque to punch through the bad air. Or, strangely enough, you might need less launch torque if the blowers provide lift and make the airplanes fly higher than expected. Again, watch earlier groups fly to try to learn.
3. All the SO flying event manufacturers sell torque meters; Freedom Flight, J&H Aerospace, Lasercutplanes, and Guru Engineering are a few.
4. Airplane construction can take anywhere from 4-6 hours for a simple design to 10-12 hours for a more complex one. My teams practice two or three times per month and three hour sessions work pretty well (the four schools I coach are very competitive; often winning Michigan States and flying times better than the eventual Nation Champion). Yes, the amounts you mention are the normal expenditures.
5. Kits will give you a big headstart. The kit companies have had the draft rules for a month or so and have built a number of prototypes and done a fair amount of testing to give you a good performing solution. You can build without a kit, but the learning curve is a bit steep if you don't have an experienced coach. Yes, the J&H kits are typically very good and I believe that Freedom Flight is shipping kits; you can contact them through their website and ask. Their website may not be updated yet to show the new models. The other two manufacturers I mentioned above typically make very good "basic" airplanes that are less time consuming to build and still give pretty good performance.

Also, look at the National Free Flight Society webpage and Youtube channel for good info and ideas. https://freeflight.org/join-learn-fly/science-olympiad/

Keep asking good questions!

Brian T.
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Re: Flight B/C

Post by pumptato-cat »

Thank you so much for your reply!
2) unfortunately, NC state would not turn off the AC. Not sure why, but it really messed up everyone's scores... I'm planning to head to school early to fly every day, so I'll try my best to talk to the administrators. My school's funky though, so I might have to fly with AC this year :(
3) I'm ordering J&H's "Senior Flyer", but their winders are out of stock, along w/ the lubricant. I don't know if the torque meter is good, thoughts? :( any suggestions for sites w/ low shipping and winders/lubricant/rubber? I was considering FF, not sure if it's worth it though.(25$ D:)
4) Is it a good idea to fly every day if possible? I think I may be able to work something out-would 1 hour a day be overkill?
5) Wait, FF is shipping '23 kits already? I'll see if I can email them! Thanks!!!
Again, thank you so much!
(Sorry for the truckload of questions D:)
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Re: Flight B/C

Post by bjt4888 »

pumptato-cat wrote: October 2nd, 2022, 3:08 pm Thank you so much for your reply!
2) unfortunately, NC state would not turn off the AC. Not sure why, but it really messed up everyone's scores... I'm planning to head to school early to fly every day, so I'll try my best to talk to the administrators. My school's funky though, so I might have to fly with AC this year :(
3) I'm ordering J&H's "Senior Flyer", but their winders are out of stock, along w/ the lubricant. I don't know if the torque meter is good, thoughts? :( any suggestions for sites w/ low shipping and winders/lubricant/rubber? I was considering FF, not sure if it's worth it though.(25$ D:)
4) Is it a good idea to fly every day if possible? I think I may be able to work something out-would 1 hour a day be overkill?
5) Wait, FF is shipping '23 kits already? I'll see if I can email them! Thanks!!!
Again, thank you so much!
(Sorry for the truckload of questions D:)
Cat,

2. All schools with modern air handlers have web-based control systems. The system can be programmed easily to turn blowers off and on at set times. With one school I work with, I had to make a presentation to the school board about supporting young people involved in STEM activities.
3. Freedom Flight might have winders in stock; call them or email them via their website. A 15:1 or 20:1 winder; either one; is fine. 10:1 is not usually quick enough for the number of turns you need (1,500 - 2,000 depending upon the rubber length and density) and the short 10 minute flight period in competition.
4. Every day practice is not really necessary and might be over exposing your airplane to potential damage, especially if flying with blowers on. The key is having a very organized approach to practice so that you progress through the standard trim strategies to find a best possible solution. Here's an abbreviated description of the trim, rubber winding and practice strategy that I coach: https://drive.google.com/file/d/14GfPgK ... sp=sharing

Also, here's a demo of me winding a rubber motor and launching a rather poor helicopter flight from 2020. This demo was me video coaching my teams during the pandemic, so I apologize for the poor sound quality and the poor helicopter flight (we were consistently flying 2:08 - 2:15 that year in Heli in a 7 ft ceiling). Airplane rubber winding is the same as Helicopter except (as you'll see in the above link) there is more backoff winding and lower launch torque flying in a typical gym with a typical propeller: https://youtu.be/aheLN19uRLI

Good questions

Brian T
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Re: Flight B/C

Post by pumptato-cat »

Oh ok, thanks! Yeah, I'm glad I asked before deciding to fly every day with AC 😅 Thank you so much for the links!!
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Re: Flight B/C

Post by jander14indoor »

While I agree with Coach Brian on the importance of working with schools to get the air handling off, I also see many tournaments where it isn't. SO, I recommend you prepare for either possibility.
- Try to get practice time in you home gym with air off to get a feel for how to trim and fly in good conditions. Start here if possible to learn how to fly if you don't have experience.
- jAlso practice with the air ON.
-- Learn how to figure out where the likely good and bad spots are by inspecting the room for air inlets and outlets. Fly and see how they affect you. This is in addition to watching other teams at a tournament, you don't always have a chance to fly late.
-- Learn how to trim for disturbed flight, it will be slightly different than a still air trim. Best still air trim tends to be more sensitive to disturbance and may recover slow, losing lots of altitude and being slow to recover. You can trim to be more resistant to stalls and bumps and recover faster. You won't get as long a time in still air, BUT, you will be more robust in a bad site. Very important.

Winders, there are suppliers for the Knight & Pridham winders other than SO suppliers, you might want to look around if the SO suppliers don't have them in stock.

Kits. If you are inexperienced, they are a great place to start. The best ones CAN do well, but you HAVE to do your job building accurately and LIGHT, then learning to fly and trim. They are NOT magic. But, once you are experienced, you can build as good or better a plane and certainly beat the kits. Again, they are not magic.
Note also! This years rules give a LOT more room for experimentation. No more span and chord limits, can be bi-plane, etc. I suspect there are design ideas out there that can take advantage of this and the kits won't have the flexibility to move quickly to a new concept if someone finds it.

Jeff Anderson
Livonia, MI
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Re: Flight B/C

Post by pumptato-cat »

Thank you! Is there any glue you'd recommend? I'm afraid of the glue adding a ton of weight to my plane. (I did Bridge last year, and the CA glue added probably 0.5-1.75g. 😭)
Unfortunately, I'm nowhere near building my own plane(I haven't even built a kit yet...) I wouldn't know how to take advantage of the new specs :( Thanks for mentioning that, would never have thought of it.
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Re: Flight B/C

Post by bjt4888 »

Cat,

We use medium “gap filler” CA from Zap. The key is to buy fresh CA glue. We buy from online model airplane websites like Stevens Aero. They won’t sell you old expired glue. Use a “two pin” applicator to place very tiny drops of glue. A 10 mg drop of glue is adequate for joints like rib to spar; a little more for attaching the nose bearing to the fuselage. With 8 grams allowed for the airplane, carefully applied glue is not a significant share of the weight budget. We also use thinned Duco cement for joints like small gussets that need a little more working time to position the part. And, of course, 3M77 spray glue to attach covering to the flying surfaces. Spray a light mist of this on the frames this glue can add several tenths of a gram if overapplied.

Brian T
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Re: Flight B/C

Post by pumptato-cat »

Thank you so much!
anything'll fly if you throw it hard enough
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