Well I got brave and hand launched my GWS Pico Tiger Moth this morning. Wins dead calm. She took off, maintained about 20 feet elevation...would not climb....slow to turn but eventually she did...then midway into turn suddenly nose dived...breaking seal for upper wing...and broken prop. Not too bad damage. Anyway...suggestions for improved flight appreciated. (this was my first build...and a lot of corrected mistakes were made in the assembly...also have just completed a Eflite Jenny JN4... Which went together much better than GWS...but afraid to maiden till I master the tiger moth).
Specs for tiger moth are...2712-17 outrunner brushless, 10 amp ESC, GWS 8" 8043 prop, and sky lipo 800mAh 20 C batt
OK, looks like you have a Heads Up RC deal (27mm motors aren't very common!). According to them you can step up to a 9050 prop but you'll only develop another ounce of thrust. That being the case you'll probably have to move up a motor size to get what you need. I'd place a call to Heads Up and see what they say. I'll bet their specs are accurate but for lower altitude.
To make you feel bad, while giving you more confidence in Heads Up, here's a Pico Moth flying on a 2212 1180kv motor and 8x6 SF prop. It has less power than you and is performing just fine. Altitude can be a killer! Gaupoman is a Florida boy like me. We fly in thick soup!
Sounds like you are underpowered and/or overweight, altitude wont be helping.. When the model "suddenly nose dived" that would almost certainly be a stall because you were flying too slow when you turned.
The larger prop should help. What weight is the model?.. Have you added anything that might increase weight over standard spec?
Just read the motor spec page... According to the data there even with your current prop you should have 13oz of thrust which on a plane that should have an all up weight of about 8oz would give you endless vertical climbing performance!
Wondering if elevation is an issue...live at 7200 foot elevation. Even my mini supercub is difficult to gain elevation.
At that altitude i would go up one prop size or go to and three cell battery. You need to keep in mind the specs on the web page were done at a much lower altitude so will produce more thrust. If you do use the three cell I would not run full throttle very much like they say though.
At that altitude i would go up one prop size or go to and three cell battery.
Even allowing for altitude (air density being about 80% of that at sea level) the thrust to weight ratio should still be greater than 1:1 (if the motor stats are correct and if there is no problem with the model).. a 1:1 thrust/weight ratio will always be more than enough to fly, regardless of altitude.
My Tiger has the headsup 2712-12, and I use a 10x4.7 GWS prop. A 800Ma 2 cell lipo. She will almost stand on her prop. Mine is also heavy with added wooden landing gear and Pilot...she will also carry a 1 oz. cam onboard. Maybe you could try this, since your JN-4 is ready...do a take off from the ground...into the wind using 1/2 to 3/4 power setting, try to keep her level and fly straight out until your 2 mistakes high, do a very slow turn either right or left, watch what she does. That JN-4 should fly all day at 1/2 power even at your alt. If she flies fine...then you have a issue with the Tiger.
Today was a very bad day! Again dead calm in am...launched my HZ champ...won't fly well after last decapitating (wing) flight...bent prop shaft. So got the micro T 28... Nose dive on turns. then got out the GWS Stick ( just completed)...from ground would not gain altitude...broke prop. Then tried the Tiger Moth again...hand launch...went 25 feet crash. Broke cowling. Then got new Eflite Jenny J...tried to take off from ground...again would hardly gain but 2 ft then head first to ground...need new prop and cowling. I've tried Firebird commander...crash, Mini super cub... Gains maybe 20 feet then crash! Only plane that flys well is the champ...but she was so battered by my learning phase that she is now retired. Ordered a new champ! So what is it? Champ flys like butter ith my dx6i....but can't seem to get anything else to take flight! Is it the elevation? Do I need to move? Grrrrrrr
Okay it's time for an irrelevant story and then I'll try to connect it to what's going on, wish me luck. I own a Sun EZ1 recumbent bicycle. It's kind of a neat thing, longer than an upright bike, has some "cool factor" high rise handlebars, but its greatest feature is that it is an amazing conversation piece. If you're going to a big fly-in with a bunch of strangers, just ride one of these and everybody wants to talk to you.
Anyway (get to the point Rockin. Pixels don't grow on trees!) I find the thing very easy to ride and it's second nature to me. But if someone were to try to steal it we could make a really ridiculous video of a fool jumping on a bike, stalling out and falling down. You see it has a longer wheelbase, coupled with a lower center of gravity because you sit 19" off the ground. The bike has an entirely different rhythm then an upright bicycle. Until you live with it awhile it is a cranky beast! When it gets through putting you in your place, you find out that the recumbent way is a good one and you wouldn't have it any other way. Whew! I better connect this with something RC, quick!
It's the same with airplanes, especially when you jump from micros to parkflier sized. You are used to giving the plane something to do and it reacts with a certain speed and momentum. But when you fly the Slow Stick you'll find that all the rules have changed. Stuff just happens slower. And the plane has much more inertia and momentum. In thin air this can be exacerbated.
It's not like you forgot how to fly. This is a different plane and she likes a different kind of handling. Take her up high and throttle back. Practice some slow turns and just baby her around the sky getting the feel for what she likes. Stall her and see what happens. Fly with different throttle settings. She'll be your friend if you'll learn her ways.
Are there any clubs nearby with other high altitude flyers? There must be some tips and tricks they've learned to deal with it. (Maybe there needs to be a high altitude flying topic opened up?) Do you have a wattmeter do see what kind of power the motors are pulling? Without seeing the flights, it's hard to tell if it's the planes or the pilot.
It seems you have a decent budget to work with. Have you considered a larger, more powerful plane? I'm guilty of bias because I own one, but the Apprentice has a huge wing and lots of power. I guess your flying space might be a limiting factor as well. It's just that your list of planes seem like ones that are powered just enough in regular circumstances, and maybe they're too underpowered for higher altitudes.
Well, I'm not experienced at that high altitude flying, these are just some I deas I'm throwing out on the table. Hopefully you'll find a solution soon. Kudos to you for not being one of those that just goes 'this plane is crap! Don't buy one!' You keep trying to solve the problem!
The GWS Tiger Moth (Pico version) is a fantastic flying airplane. Is there a club around that can help you? I suspect you just need a bit of help to get them setup properly and then you will be good to go.
I fly my moth in a single BB gym. It is a magic airplane when setup properly.
Thanks for ll your help and suggestions. Nearest club is an hour drive from here. Now...after searching thru posts I think the olution is more pitch to the pop for elevation...( ordered several to try). Also this morning tried out my Hawk Sky ith the sme results. Nose dive to the ground. So far Champ is the only one to ly up here! Hope the props work as it is a cheap fix!
I use a GWS 2205/15T with an 8040 HD prop, Thunderbird 18 ESC, and Thunder Power 2S 910mah batteries.
It will climb vertical but will also fly as slow as you like. As for control, increase the rudder and elevator throws as much as you possibly can. The Pico TM needs a lot of control throw to really make it maneuver.
As far as props go, you may also want to try larger diameter with the same pitch propellors. I'm still relatively new at this, but as I understand, you'll get more speed by adding pitch, but more power by adding more diameter. Which one is better for high altitude???