LukeWarm Show full post »
LukeWarm
To make it clearer, I rewrote the section in question

16) The Big motor thing: When going to a bigger heavier motor; You will need a bigger heavier ESC. If you want the same amount of time in the air, you will need to use a bigger heavier battery. You may also have to reinforce the plane. When adding all of this extra weight, many people are disappointed because they do not see the performance increase they had anticipated. On a 30 oz plane with more power, because of the higher wingloading, the performance difference between a 20 oz plane and a 30 oz plane is huge.
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johnw5734
Right on, Lukewarm.
In the RC glider competition world, low drag and light weight is where the performance is. The same approach works great on our scratch built park jets. You can always ballast a light plane but you really don’t have that option with a heavy one.
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F1wanabe
I agree totally with low weight set ups. I had a conversation (!) a while back on this point exactly. A v1 plane on mjv3, 20 amp esc and 1600 battery weighing 15-17 oz performs extremely well. Great in fact. Do I feel the same when I install a smjv2? A 22-25 oz v1 with smjv2, 50 amp esc and 2200 3s has more thrust and more speed, but other than that performance suffers. Wing loading increases and a shift in cg almost always results with negative results. Motor and battery upgrades often cause an overall DROP in performance. A properly set up v1 plane on a mjv3 is very difficult to beat. Now I think the v2 planes are able to benefit much more from upgrades as wing loading and cg changes are less dramatic. Thanks for posting this, Luke! Lots of beginners have these questions that need to be answered.

My youtube :
http://www.youtube.com/gstrysky
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jm0348
Thanks for the info Lukewarm! I can attest to #3. Backwards just doesn't work. Unfortunately it took 4 attempts and 4 wingovers right into the ground to figure it out on a F22v2. Oh well, I'm a beginner. I bought a HZ Supercub LP and figured out how to keep it in the air and more importantly, how to bring it back to the ground in one piece. I scrapped the F22 and built and have been flying the F35v2 elevons only and I have to say, it is way easier to fly than the Supercub. It handles wind 10 times better than the Supercub and it goes where I point it with little effort. I just finished another F35v2 with all the bells and whistles. Thanks to Svetlin and Rodrigo, I got all the controls moving in the correct directions with mixing. Supposed to be calm winds tomorrow and through the weekend so I will maiden the new plane.
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LukeWarm
The two problems I see most are The prop is on backwards and The plane is built way too heavy.

The prop is on backwards is due to a lack of knowledge, The prop does not come with instructions, so every time you install a prop, you have a 50/50 chance of getting it wrong. You can learn how to correctly install a prop in both of our courses, and it's all over this forum. Once you learn, it should be a part of your preflight checks because you will do it again.

The plane is built way too heavy is also due to a lack of knowledge. For his first flight, he wants to fly the best, so he loads it down with all the bells and whistles he cant think of. He over builds the plane so bad, that it takes two rocket scientist and a witch doctor to figure out how to dial it in and get it in the air. It pays to start simple and tackle one problem at a time. When you over build, there are too many things that can go wrong. Another thing I see is too much glue. You should use just enough glue to hold the plane together; if it hits the ground hard, a glue joint braking may save the plane.

There are two major reasons I see for crashes. The pilot does not do his preflight checks, or the plane runs into something. The second one is normally causes by ether the first one or mistakes in orientation.
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Keith_5031
This is a good thread. Wish I would have seen it sooner. Would have solved quite a few issues.
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LukeWarm
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This is a good thread. Wish I would have seen it sooner. Would have solved quite a few issues.
These are all good information resources:
The Scratchbuilders Beginner's Guide
They show you how to build a foam plane
Resources This has shortcuts to information threads
RCPowers Blog
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Anthony Yurong
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I guess no one liked my list. It's the answer to many questions we see all of the time. I am supprized that no-one made a post to add something to the list. Maybe i should have made the post shorter.


Thank you for that wealth of information!!!
Aloha
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Brudder
Just read this thread, all makes sense now, Still building my first jet from your site but,,, I can see I have a tendency to over build . Thanks for the pointers
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TnTiger
Another fine post!!!very informitive
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