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Old Apr 12, 2011, 10:33 AM
I feel the need...
Azn_Ace's Avatar
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Originally Posted by Maxthrottle View Post
Key element is figure out what you're up against and try. Nothing is going to happen unless you try.

Saying that its easy.....is relative. I'm sure I'm not the only one who's observed drivers that make you wonder how in the world the got their license. Or others who have failed their test a few times. And for those who just barely got their license and then face bad weather....relative......
Certainly flying a model is harder than driving a car.
I don't know how any of us could tell if we are talking to someone like that from these forums, but even if we came across one who had such difficulties, we could still give them pointers on what to look out for and encourage them to Try!
Ask and gather as many good pointers as you can for the design you're going to try and go out and... try!
My point is if you're a beginner attempting to fly something larger than an Ultra Micro, then try in a controlled environment (ie, flying club) - not in a public park where you can hurt someone... I've seen my share of yahoos...
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Old Apr 12, 2011, 10:48 AM
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Totally agree. Its not as some may be inadvertantly implying that you can't get in over your head. Not all designs are the same and sometimes there are stuff to watch for.

I've been flying lots of stuff for decades and still occassionally have a departure now and then.
Experience helps big time and finding how and why from these forums helps big time too.
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Old Apr 12, 2011, 12:12 PM
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My first attempt at an EDF was a disaster. I had success with a mini cub and some micros, then PZ warbirds. I was told if I could fly the PZ P-51, I could easily fly an EDF.

Well, once I figured out the launch technique (5 hard nose-ins), I finally got a good launch....and there it went....I try to turn and it would just spin (roll) like a drill bit....ending in disaster. I had tried EDF's on sims, and figured I would be fine. I abandoned the idea of EDF. At least until I got used to the speed and agility of the Funjet. I've had relatively great success with EDF's ever since. Problem with a lot of cheap, but attractive EDF's is that they lack the needed thrust and CG is always a guessing game and tend to stall too easily.
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Old Apr 12, 2011, 02:33 PM
I feel the need...
Azn_Ace's Avatar
Orange County
Joined Feb 2011
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Quote:
Originally Posted by restlessswind View Post
My first attempt at an EDF was a disaster. I had success with a mini cub and some micros, then PZ warbirds. I was told if I could fly the PZ P-51, I could easily fly an EDF.

Well, once I figured out the launch technique (5 hard nose-ins), I finally got a good launch....and there it went....I try to turn and it would just spin (roll) like a drill bit....ending in disaster. I had tried EDF's on sims, and figured I would be fine. I abandoned the idea of EDF. At least until I got used to the speed and agility of the Funjet. I've had relatively great success with EDF's ever since. Problem with a lot of cheap, but attractive EDF's is that they lack the needed thrust and CG is always a guessing game and tend to stall too easily.
Yeah, spectators usually see how cool EDFs look in the air - then they want to go out and get one. Problem is the cheap ones are usually underpowered and they end up stalling them and crashing.
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Old Apr 12, 2011, 03:46 PM
You are a "go" for reentry
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Quote:
Originally Posted by restlessswind View Post
....Problem with a lot of cheap, but attractive EDF's is that they lack the needed thrust and CG is always a guessing game and tend to stall too easily.
Quote:
Originally Posted by Azn_Ace View Post
Yeah, spectators usually see how cool EDFs look in the air - then they want to go out and get one. Problem is the cheap ones are usually underpowered and they end up stalling them and crashing.
Not saying either of you don't know your stuff but for many CG and underpowered is often blamed for stalls. On any model I reconfirm if the CG was calculated correctly so that I'm not tail heavy or over sensetive on the tailerons. Once that's covered a stall would have to be because of me causing it. If I could get the model in the air would show sufficient thrust. To stall would need to pitch up and slow down or speed stall, something a pilot is supposed to judge. Otherwise you'ld never get off the ground. I don't know I'd see a stall in that case as my fault.

This is sometimes where things seem to be a mystery EDF, tip stall, root stall, flapperons, tailerons etc where the problem is explainable but is mispercieved for something else.

Cheap stuff may not help in some ways but as you get a better understanding you have an idea if something doesn't look right. I fly cheap stuff just fine or I look to avoid something that may be very unstable or a handful.
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Old Apr 12, 2011, 04:19 PM
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this is the problem with "most" RTF foamies..............they need an extra cell in order to perform in a "kinda jet-like manner". case in point: my Euro sucked bad on 3S, but when I went up to 4S it was like a completely different animal that put a really large smile on my face.
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Old Apr 12, 2011, 04:31 PM
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Originally Posted by LuvEvolution7 View Post
this is the problem with "most" RTF foamies..............they need an extra cell in order to perform in a "kinda jet-like manner". case in point: my Euro sucked bad on 3S, but when I went up to 4S it was like a completely different animal that put a really large smile on my face.
I never thought of upgrading my F4D-1 Skyray to 4s, your right though, it didn't have jet like performance at all, you had to be VERY conservative with your energy, granted it can get up to high 60-low 70 mph range on stock stuff, though it still sucks power wise. Might have to try it on 4s, too bad I just stuck it's ESC in my 50mm F-22
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Old Apr 12, 2011, 06:45 PM
FLY HARD OR FLY HOME TO MUMMY
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Joined Jan 2011
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there is nothing wrong with modifications, however it seems that it is these very same mods that change the cg and cause aircraft to behave badly in many cases. i bought my t45 64mm edf and have flown it stock since, with the exception of changing the aileron servo for something of better quality. is it underpowered? it will perform a half cuban right after take off..so i would say definately not. yet the same aircraft will happily fly around at 1/3rd throttle and is as docile in the stall as my j3 cub, in fact even more so without the torque from a propeller to upset it. i also find my 90mm hornet to be a very honest flying aircraft, again with no mods. having said that i flew the pair of them back to back this morning and i can confidently say that the 90mm hornet is not suitable for a first edf, unless you have some rc experience flying some thing that gets around at similar speeds. its simply too fast and uses up too much sky. what i am saying is that edf is not that bad if you choose the right one as your first(edf, not first rc plane), and there is nothing wrong with stock kits provided you choose wisely and do a bit of research. stock kits don't make people crash. lost orientation and not understanding stalls do. many people do not understand that stalling has nothing to do with speed, an aircraft stalls because you have exceeded the critical angle of attack.the reason people say keep the speed up is that the effect of this is you need less angle of attack to stay in the air, giving you a margin of safety. all bets are off though if you are are overcontrolling with the sticks, because regardless of speed, if you increase the angle of attack quick enough(eg yank back on the stick) the aircraft will still stall.
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Old Apr 12, 2011, 09:59 PM
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Originally Posted by snivilous View Post
I never thought of upgrading my F4D-1 Skyray to 4s, your right though, it didn't have jet like performance at all, you had to be VERY conservative with your energy, granted it can get up to high 60-low 70 mph range on stock stuff, though it still sucks power wise. Might have to try it on 4s, too bad I just stuck it's ESC in my 50mm F-22
if you are gonna go 4S, make sure you go with a 60 Amp ESC, since you are gonna be consistantly in the 40+ Amp range..............a little extra too, with fresh packs before the Amps settle out. you can get away with a 45 Amp, but I like the 60's for that little bit of extra cushion. also make sure your motor is capable of pulling the extra constant Amps. I was lucky that the V1 Sapac motor is more than capable of the extra Amps, so it was a simple swap of pack and ESC.
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Old Apr 12, 2011, 10:05 PM
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@ jb,

I'm totally not disagreeing with you about these RTF foamies being "honest" fliers, because generally they are, even if most are a bit timid or marginal at best. up the cell count and you turn "honest" into downright enjoyable. I do agree that it messes with your CG, so this has to be compensated for with battery placement and/or equipment placement. also remeber that the extra weight will change the wing loading, so be prepared for that. if you've never flown your plane before the mod, then there's nothing to compare to, but for those that have, it's worth noting. that being said, it'll bleed speed more quickly in turns, stall sooner and generally require slightly more energy to maintain the original energy state before the mod. with those small things in mind, you'll have so much more fun flying. take for example, Jb's 90mm F-18, if it's a 6S plane, I would up the count to 7S on the same fan combo and see what it can do. I guarantee it will be a lot more enjoyable than on 6S. just don't go crazy and overspeed the fan combo, or you'll stall the fan out and have less than you had before. for that reason, one cell is often the best cure for a lame bird, without too much additional hassle of adding it.
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Old Apr 12, 2011, 11:35 PM
I feel the need...
Azn_Ace's Avatar
Orange County
Joined Feb 2011
459 Posts
Quote:
Originally Posted by Maxthrottle View Post
Not saying either of you don't know your stuff but for many CG and underpowered is often blamed for stalls. On any model I reconfirm if the CG was calculated correctly so that I'm not tail heavy or over sensetive on the tailerons. Once that's covered a stall would have to be because of me causing it. If I could get the model in the air would show sufficient thrust. To stall would need to pitch up and slow down or speed stall, something a pilot is supposed to judge. Otherwise you'ld never get off the ground. I don't know I'd see a stall in that case as my fault.

This is sometimes where things seem to be a mystery EDF, tip stall, root stall, flapperons, tailerons etc where the problem is explainable but is mispercieved for something else.

Cheap stuff may not help in some ways but as you get a better understanding you have an idea if something doesn't look right. I fly cheap stuff just fine or I look to avoid something that may be very unstable or a handful.
That's my point - inexperienced flyers stalling the plane due to pilot error. It doesn't help when the EDF is also underpowered because it's less forgiving and you don't recover. With a powerful setup, you could potentially mask the pilot error by "brute forcing" it.
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Old Apr 12, 2011, 11:39 PM
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^^^^^ +1
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Old Apr 13, 2011, 12:43 AM
Live to fly
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Sacramento
Joined Apr 2005
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There are some of us that pick up anything fast...I too have seen pilots with very little stick time have success...just more that don't!
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Old Apr 13, 2011, 02:09 AM
You are a "go" for reentry
Maxthrottle's Avatar
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Quote:
Originally Posted by Azn_Ace View Post
That's my point - inexperienced flyers stalling the plane due to pilot error. It doesn't help when the EDF is also underpowered because it's less forgiving and you don't recover. With a powerful setup, you could potentially mask the pilot error by "brute forcing" it.
Hey, I don't have the call sign maxthrottle for nothin
For some that extra power can also make a crash happen much faster but agreed. Power is ones friend.
Near 1:1 is always nice but considering the thread and real world seldom has 1:1 TWR, you generally try to avoid getting into a low control config to need power to get you out of a situation.

Because models don't all fly the same, onw does well to look for the little things that make a difference. Its a matter understanding those little things and flying within that envelope.
This is not just for EDFs but for any model.

Some will say EDFs are easy which they can be as long as you fly them within their limits, underpowered or not. But looking for power to get you out of an issue likely ment the pilot overlooked, forgot or may not have known a certain limit about EDFs that got them into the problem in the first place.

Which is what this thread is just putting out there as a caution. There are thing you do well to know before you just jump into the deep end.
Its not saying be terrified of deep water, have fun swimming, but our control is based on understanding.
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Old May 07, 2011, 03:37 PM
You win again gravity!
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UK
Joined Jan 2010
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^^^^^+1.

You shouldn't fly something for which you don't have at least a rudimentary understanding of how it flies.
For example, don't expect an SR-71 model to have sublime low speed handling! It will stall, and you will crash. Don't blame the model (mostly! sometimes some models are just junk!)
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