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redgiki
02-26-2006, 06:29 PM
After weeks of the bird sitting in my garage waiting on a break in the weather, I finally maidened my e-Flite P-47 yesterday. Here are the specs:
Park 450 motor
Dymond 2100mAh LiPo. Yeah, there's no balance plug on these batteries, but they are cheap, work great, and seem to last a long time when recharged at around 0.4-0.5 amps.
Hitec Supreme radio (a little heavy for this bird, and behind the CG, so I'm going to replace it with something lighter)
Hitec HS-55 servos (3)
E-Flite brushless ESC
Master Airscrew 10x8E and E-Flite 10x8E props
Dubro scale wheel struts
Just so you know, I really like flying this bird. She's very pretty in the air, stays up for a good long while (about 12 minutes on a 2100mAh battery), and is a blast to fly. I'm going to list quite a few downsides, but it's in hopes that my bad experiences can help someone else :)

Positives:
Very easy build. I have very little build experience (I prefer flying to building), and found it very straightforward and well-documented for the power choices I made.
Once trimmed, she's very solid in a light wind.
The 10x8E prop is well-matched for this bird, even at 5000 feet elevation.
The Park 450 outrunner is a fine motor for this warbird. Very short takeoff rolls, and lots of power. At my elevation and with the extra weight of the Dubro scale struts and lots of nose weight (more on that later), I couldn't hover her using this motor, but nevertheless it provides a very pleasant flying experience.
Having a rudder available in a plane this size made my landing approaches in a crosswind much easier and prettier than in an aileron/elevator-only ship.
It's a damn pretty little electric in the air, even with a little fuselage and wing rash.
Inverted flight is fairly easy to hold. Not as easy as, for instance, a ParkZone Stryker, but with this motor on the front I never worried about not having enough power to push or roll out of the invert and maintain altitude.
Even with extra weight due to additional nose weight, epoxy, a heavy radio, she cruises just fine at 1/2 throttle doing lazy figure-eights and circles. At 3/4 throttle, she can do most aerobatics, and at full throttle she can do enormous loops.
For a warbird, she's very docile. The nose just mushes in a stall, rather than tip-stalling like the P-51. With factory throws, the roll rates are just slightly faster than scale at full deflection.
Landings were a non-event. I did four approaches to learn her glide path, then brought her right down on the fifth one. On the second flight, the first landing approach was perfect and she settled down at 1/3 throttle easier than my J-3 cub.
The battery bay fits a Dymond 3S1P 2100mAh LiPo battery perfectly. Since these are the same size as the Thunder Power 3S1P 2100mAh, those should fit fine too. If you have fatter packs than these narrow-form-factor ones, you may have better luck with not having to add nose weight, but you'll also have to hog out the foam in the nose a bit. Given that these narrow LiPos are almost exactly the same width as a 2/3A battery, you should also have good luck with NiMH packs. And hey, with a NiMH..... less nose weight required!

Negatives:
You're going to have to add substantial nose weight if you use the rudder option. From my bench balancing during build, with just aileron and elevator, no landing gear, the CG appears spot-on with the stock motor and prop; using a light brushless motor, rudder servo, rudder hardware, glue, and tailwheel affects the CG mightily. I'm thinking of building a second one in a pure slow-flyer configuration without gear, rudder, or brushless motor later.
The stock CG indicator is slightly too far forward for perfect hammerheads. Although easy to handle, yaw performance suffers. With the CG at the factory location (using a CG machine), the elevator required quite a bit of back trim to maintain level flight, and exhibited classic signs of nose-heaviness on landing approaches.
To balance at the factory CG, I had to use the full bar of clay, pressed around the nose, and several additional small weights. The weights will be going away one-by-one until I find the sweet spot on the CG; I suspect it's about 1/4" back from the factory-indicated CG.
Like most uncovered foam models, the finish is very easily damaged in the hangar. I already have a scratch from one of my fingernails, and a pretty ugly white-ish bruise on the side due to an accident with my CG machine while balancing.
Trying to pry the cowling off in order to mount my motor was frustrating. They need to let the paint dry just a little longer before shoving the cowling on at the factory. Or maybe they could wrap the fuse in tissue or something so that the cowling slips off easily.
The space is very tight, even for a razor saw, when trying to cut the engine mount stick. You're going to end up taking out a few small hunks of foam even if you're really careful. They are concealed beneath the cowling, so it's not a big deal.
The lack of a steerable tail wheel complicates landings a little; once the tail drops, your level of control drops, too. That lack also complicates takeoffs if you attempt to do a scale rollout at half or three-quarters throttle rather than the "jump into the air" full-throttle roll.
The two wing panels should really be saved for last in the build. If, as I did, you're going with a flaperon setup rather than a y-connector, the flaperon adjustments may require repositioning of your servo arms. And that double-sided tape on the wing panels really sticks hard! Note, however, that using flaperons as flaps is strictly optional. She floats lightly even in the full-house configuration and nose-heavy.
She doesn't handle high winds really well. Like most park flyers, if the wind is faster than 10MPH, you might want to consider keeping her on the ground if you aren't confident at the sticks.
The stock throws provide too much elevator and too little rudder/aileron for my taste. Your taste may vary, and luckily suiting that taste is probably just one adjustment away.
The stock landing gear location is susceptible to nose-overs on landing. Bending them forward so the axles line up with the leading edge of the wing when sitting on the ground (weight on the axles) clears this up just fine, while providing plenty of clearance for the stock prop.
The little black wheel holders suck. I replaced them with some nylon ones, because one of the wheels fell off during the second landing.
Some people report that the paper hinges are weak on the ailerons. Mine does not appear to have this problem, but I still don't like how they look.
The indicated location for the ESC and radio is rather far back. I put my ESC in the nose, and trimmed some foam to move the radio as far forward in its tray as I could.
Overall impressions:

The E-Flite P-47 is a solid, large-ish park flyer, a ton of fun to fly, and really good-looking in the air. Although fairly slow-flying, with the Park 450 motor it's really too fast to fly within a baseball field, but a large treeless park may do the trick. I fly at an abandoned runway, and there was more than enough space :) My personal bet is that, in an aileron/elevator-only combination without landing gear, on the stock motor, this bird will be a great flyer even in smaller parks.

With factory throws, rolls are scale-like and pretty. There's plenty of power to push through moderate winds, but gusts above 15MPH will easily throw her around in the air since she's so light. Like many other short-nosed warbirds, tail-heaviness can be a problem; you should be generous with the nose weight, at least for the first few flights, and aim for at or very slightly behind the factory-indicated CG location.

I like it!

One question, though. I notice that my rudder servo only deflects about 50% on one side. There is no chatter from the servo, it just doesn't move all the way. My flying buddy noted this during our preflight yesterday, but we decided to put her up anyway. The transmitter has no EPA set for that servo; should I just plan on replacing it?

redgiki
02-26-2006, 07:15 PM
A few more notes about the two first flights:

The E-Flite 10x8E prop puts out substantially more power than the Master Airscrew. However, the E-Flite prop was also pretty far out of balance right out of the box. A prop balancer and some sandpaper fixed that up, but be aware. The MA was perfectly-balanced right out of the box after sanding the couple of stray pieces of flashing off, and is a much, much stiffer and heavier prop. The MA is a little less thrusty, but usually that also means that you'll have a little longer runtimes. Regardless, both props work great. The E-Flite prop has been out of stock for weeks (I think it's a new item), so that's why I have the MAs.
My left aileron is a little bit further away from the wing than the right one. This results in a little less deflection, it seems, though I'm not sure. I had to add three clicks of right trim on the maiden, then it tracked perfectly. If I end up doing a substantial rebuild at any point, I'm cutting that aileron out and putting in new CA hinges with less of a gap.
There's almost enough room to put two TP2100/Dymond2100 batteries in the battery bay. I think I'm going to take out a bit of foam, put in two batteries in parallel, and see if I can ditch my additional nose weight. If that works, then I'll have a bird with over 20 minutes of runtime at full-throttle. Not bad, and as much nose weight as I had to put in, I think it will work fine. A little more all-up weight will help in the high winds we get around here, too, and as "floaty" as this is on landing, I think it can handle the weight just fine.
The little magnet holding on the cockpit hatch cover concerns me. It just doesn't hold very hard. I'll have to do a few more inverted pullouts to see what happens in high-negative-G situations :)

redgiki
02-26-2006, 11:56 PM
So for my final addition today, I have to comment on landing on grass. I had only landed on asphalt previously, and it worked fine: bring it in fairly hot, flare at the last moment, life is good.

I followed the same pattern today, but with a critical difference: I was landing on soggy ground with winter grass in a local park. I brought it in hot, bled off some speed, flared, and... the landing ripped the tail wheel off, mount and all.

Next flight, I was bummed, but figured I could do a wheels landing before dropping the tail on the foam. Brought it in and... it ripped the right front wheel off. Mount and all, right out of the foam. The plastic mount is much stronger than the foam. Just like the tail wheel, though, I realized how little glue they use to secure these things in. Just a drop on the front, and a drop on the back of the mount. There was very little damage to the foam, and on the wing it was concealed by the plastic cover plate.

Realizing I'd have a balance problem if I left the other wheel on, I went to my toolkit and found I had left the screwdriver home. So I walked back and pulled the last wheel out by hand. Minimal damage to the foam, again. They hardly hold those plastic mounts in with anything!

My observations:

Well, first off, don't attempt to land with gear on wet, soggy ground with normal-length grass. You'll rip your gear out of the foam. I think stubbier grass, leveller ground, or dryer ground, and it wouldn't have been a problem. I should have been tipped off when I tried to rise off the ground for takeoff, and it just went nose-over rather than scooching forward. Kind of a clue that the grass was too long, but I ignored it and hand-launched.

But second observation? HOLY CRAP, that thing is lighter and more manueverable without the wheels and mounts! Much faster roll, much faster pitch... I didn't notice any improvement in yaw. Plainly faster in the air without the gear drag.

I think the gear are staying off this bird from now on; although I will miss rising off the ground, it just flies a lot better without the gear. For landing, it belly-flops in grass very gracefully, with no damage and just a very slight grass stain behind the set screw holding the wings on. It's now quite nose-heavy, even using the factory CG marks rather than 1/4" back as I prefer, so I can reduce weight even further from the nose now with the tail wheel off. With no gear, this thing flies like a sweetheart, even nose-heavy.

My two cents. If you're going to build this plane to be a hangar queen, or you really want to taxi around, build it with the gear and put a steerable tail wheel on. If you're more interested in how it looks and flies in the air, and have a reasonable grass patch to land in, leave 'em off.

Don Sims
02-27-2006, 01:32 AM
Thanks for the excellent insight and comments. You need to post some photos of your P-47 when you get a chance!

redgiki
02-27-2006, 05:10 PM
...post some photos of your P-47 when you get a chance!

OK, but these are going to contain several examples of "what not to do"! Left to right:
Rudder photo shows the rudder mod in action. You'll note that, if you do 45 degrees on either side like the instructions indicate, the white area is really large and ugly. Either get happy with the yellow and black paint afterwards, or you can do a MUCH more modest 15 degree or 20 degree sanding job and have a much smaller line. There's really not a lot of room for rudder travel.
Wing underside photo. The point of this is to show you what happens to the wing panel if you remove it repeatedly after removing the wax paper from the double-sided tape. Note that it's peeling and lifting? I need to re-tape it. I strongly recommend just relying on the two velcro patches to hold the panel in place until you are ready to maiden the bird. Oh, and a wing servo (Hitec HS-55) popped out on a hard landing; I'd recommend using a drop of epoxy to ensure the servo remains in place even if you do a wing-over.
She looks really pretty head-on. Kind of imposing, particularly in a dive :)
The diagonal top-down shot is just to show her off a bit.
The next shot, of the right side of the cowl, is used to show you what not to do. Includes some hangar rash, a cowling I want to replace due to damaging the paint and plastic so bad trying to get it off, and the CG location.
Close-up of the pilot. Definitely a stand-off-scale bird, but really pretty in the air.
Detail of where the tail wheel ripped off on a landing on damp ground. If you're using the gear, stick to asphalt or very well-maintained grass with the E-Flite P-47.Overall verdict: Looks "foamy" up close. Easily hangar-rashed. Flies great, and looks great in the air. The way I figure it, if I want a bird that looks fantastic up-close, I'll make a non-flying plastic model :)

EDIT: The day was too beautiful, so even though I work nights I stayed up late to fly through four batteries. The wing cover you see that is a little bit off actually partially came off during a flight, and I brought her down for a quick repair with more double-sided tape easily enough. It's always surprising how quiet this bird is. Now that the props are correctly balanced and the CG is set up right, she can maintain level flight in a figure-eight at around half throttle.

With my timer set for ten minutes (bringing her down by 11), with the landing gear and casual flying I was draining about 1750 mAh. Without the landing gear, that's down to about 1500mAh, and I'm routinely going from full-throttle on the up side of the loops, to 1/4 or so on the downhill slope. That means this motor combination is only averaging about 13-14 amps in flight with the stock prop.

Still working on my four-point-rolls; my nose keeps dropping. Tried scooching the CG even further back to make the rolls more axial, but I reached the point of supreme squirreliness and "I'm glad I was able to land it"... so 1/4" back from the CG marker is a bit too far!

Piperfan
03-04-2006, 09:36 PM
I have one of these and it fly's great. :) Get rid or those wheels! :confused: The're junk and warbirds don't fly with wheels down anyway unless landing. :o I epoxed a couple of wooden mixing sticks to the bottom of the fuselage and sanded em and painted to match under the wing and belly land the plane on any surface. Snow and grass are the best but it you do it right the asphalt can be your friend too. Asphalt will have a tendency to scratch the prop and bottom more then I like so I stick to grass. Landing is like any other plane. glide slope to flare transition and skid it in. No worries mate. The 47 was one of a hand full of planes in the war that saved pilots neck if they had to go in wheels up. That beautiful large belly. :cool: The great thing about this plane is that it is totally pradictable at slow speed. No tip stalls or a mushy feel to the controls. My plane balanced perfect right out of the box. No fiddeling. I did have a 450 in it originaly but put that in my P51B and put a 480 in the 47. Its a rocket ship now. Hand launches are not even an issue. Just half throttle and it is flying out of my hand. TP 2100 24c is the power and pheonix 35 esc. Will post pix of the belly skids. I did a belly landing the first flight with out the skids and tore up the foam a bit. Not bad but knew it needed to be protected.

Phred
03-05-2006, 04:40 AM
Hey Piperfan,
I have a pheonix 25 and would like to do the same set up as your bird. Have you put a watt meter on it? Any thoughts on if the P25 would be overstressed? Thanks.
Phred

Piperfan
03-05-2006, 05:49 PM
If you try to use a pheonix 25 it won't work. The draw from the motor at even have throttle is enough to draw down the available volts in the battery the esc kicks in. Tried that done that. I had to switch to a 35 and get a new TP 2100mah with 24c output capacity. I am drawing about 12 to 17 amp at full power on the meter. The thing is a rocket ship! Literally takes off from my hand. No toss neccesary. Better to have more available power. Even so after about 10 minutes of flying, if I push the throttle up hard the esc kicks in since the available voltage from the battery has been lowered. I try to make sure I have enough room between the aircraft and the ground in this event. This plane is awsome for doing low passes high speed or slow. This thing is so stable at slow speed! I have to aplaud E-Flite for getting this one right. I am hoping they come out with some other warbirds in this configuration. Perhaps a FW-190 or a Zero? A F6 Hellcat makes an excellent belly landing plane. One thing I don't understand is why even bother with landing gear? The plane does not take off in a scale manner since being so small its not as controlable on the ground like my 1/4 scale. Most park flyers are like this. Well, its off to fly. A little windy here today but no problem for the Jug. This thing penatrates any wind just about. Its my fingers I am worried about. About 38 and blowing about 15mph.

Phred
03-06-2006, 04:15 AM
Piperfan,
Good info. I'll rethink my motor/esc situation. I had planed on an axi2212 w/ the CC25 for my modded Parkzone P-51, but maybe thats too small a setup? I'm still learning this e-flight stuff. I'm a reformed nitro flyer, but still fly them now and then. BTW, I used to be an A&P and worked on a few Pipers. Cubs to a Malibu.
Phred

Piperfan
03-06-2006, 03:06 PM
Phred,
I too once flew the oil spewing noise makers. I still have a few 1/4 scale models that are running on Gas though. Its to expensive to move the big ones to Electrics yet. After a few hicups of my E experience I found that your better off spending a bit more and getting a set up more powerful then one that just barely get it in the air. The set ups that were suggested early in my E ventures were no good. Thank good ness for the coming of lipos and outrunners. Can't wait for whats next.

slowmover
03-24-2006, 04:34 PM
Specs: E-Flight P47
HC2812-1080 Outrunner
TP 2100
3 Blue Bird 371 servos
Blue Bird 4 chan. reciever
Phoenix-25 amp esc
Bench test: 11amp
24.69 AP
270 WP
250 W
First flight impression::D :D :D :D :D . This thing is a rocket at full stick. Best at just under 1/2 throttle.

alienx
03-24-2006, 08:45 PM
Mine is sitting with all it's hardware and battery on the front porch as we speak. I can't wait to get home!!

Crash9
04-06-2006, 06:29 PM
Piperfan is right about the landing gear. Just added weight and the plane flys and looks better without it. I resently rebuilt my P-47 and glassed it, and when I did I removed all the landing gear mounts to save on weight. This is a great little plane. here's mine. http://www.rcuniverse.com/forum/m_4107144/tm.htm

alienx
04-06-2006, 08:01 PM
All you guys that fly with no wheels, how do you keep from banging up your prop? Specially this one, it's 10 inches? I would love the simplicity, weight savings, and ability to fly without a paved strip, but it just seems like you will keep putting the prop out of balance.

JustinG
04-06-2006, 09:34 PM
I've been flying my E-Flite P-47 for a couple of months now, I love it. It's probably my favorite plane. Last time I flew it though, one of the gear came off on landing, and I've been dragging my feet getting it fixed and airworthy again. I was planning on putting it back on, but after reading these raves, I may just rip the other gear off and hand launch it... I'm scared of hand launches though, always afraid it's going to just lawn dart into the ground before I can get my right hand back on the stick. :o

redgiki
04-07-2006, 03:55 AM
One thing I don't understand is why even bother with landing gear? The plane does not take off in a scale manner since being so small its not as controlable on the ground like my 1/4 scale.

This is only because we're massively overpowered :) I did a 1/3 throttle rollout on the salt flats the other day. About 2 seconds in, the tail lifted nicely in a scale-like fashion all on its own, and about 4 or 5 seconds in a light touch of elevator brought it off the ground.

It looked so cool doing a low-throttle takeoff, that even my non-modeling father-in-law commented on how he really liked that takeoff.

Of course, on rough asphalt or grass, my takeoff roll usually resembles something more like "Zzooom!" and it's instantly fifty feet in the air. Or hand-launched.

I have now dispensed entirely with the under-wing covers, as they are just added weight and don't add much to the appearance of the airplane. Thus, the landing gear are easily removeable in about 2 minutes with a jeweler's screwdriver, so I take 'em off when I'm flying at the park, and put 'em on when I'm taking off from asphalt at the field. Best of both worlds.

I replaced the wing, because it was so scratched up, and the elevator too after a two-year-old broke off the corner beyond the panel line and ATE it! I glassed the two surfaces and the belly pan. Minimal weight gain. With gear and battery, my bird weighs in at 25 ounces. Without gear, I save a bit and, as mentioned, it does fly and look much better in the air.

Still a daily driver, every time the weather is nice enough. Sans wing covers, I have the flexibility to belly-land or gear-land pretty much at-will if I take 'em off or put 'em on.

redgiki
04-07-2006, 04:03 AM
All you guys that fly with no wheels, how do you keep from banging up your prop?
Cut your motor right before your final flair. The way this wide-body is angled, if you're landing in grass you'll never break the prop.

Seriously, I've belly-landed dozens and dozens of times, and never hurt a prop when doing so. I've hurt it more with nose-overs with the landing gear on!

This darling isn't like the ParkZone P-51 that breaks props at whim on landing. If you get your speed down as low as it can go, and do what I call the "flare and flop", the belly of the craft has slowed you down to basically nothing by the time it finishes the roll toward the nose on a belly landing. The plane really works well for no-gear landings. It's like it was made for it. Matter of fact, if you just go elevator/aileron with no gear, stock motor, and a LiPo, the bird is so light and slow on the final approach you'd swear it was going to stall on you... but it doesn't.

That said, I'm going to try out some 4S LiPo batteries, and try a much reduced prop size to see if I like a lower-thrust, higher-speed bird :)

Something that will also help reduce prop breakage is to move your CG back from the factory indicator a bit. Not much. Mine's 1/4" behind that. You'll gain a bit of elevator response, so you may have to mechanically dial it down a bit from what you're used to, but the difference in aerobatic performance and landing angle is worth it. Takes a bird that floats nicely on landings, and makes it float even better :) You will, of course, want to do the usual upline and downline tests (like with a pattern plane) to make sure you're not tail-heavy.

Grasshopper
04-07-2006, 04:15 AM
You guys are really frustrating me! Mine just arrived yesterday. I've got a Spektrum DX-6 for it on it its way here now and just ordered 2 2100 mAh 3S 15C lipos and charger this evening. The only thing I have left to get is the ESC. All this talk of how great they fly is really making me want to get out and throw it in the air. Unfortunately it's been really windy here for the last 6 weeks and we're currently under a tornado watch.

It's good to hear that it's that nice flying of a plane. I CAN"T WAIT!!!!!!!!

Tom

Crash9
04-07-2006, 07:14 AM
Just like everyone who has flown this bird say's it can fly slow and stable it's the same reason I think it can be hand launched so easy and then "belly flop" on the grass. But the prop thing can be a draw back, I go through 1 every 10 to 15 flights even though I dead stick to the ground they can still be damage, but then again I struck a few into the asphalt also. Personally I never wanted to go without the landing gear and I rather use it, but my experience with it and bending it back in place a few to many times (it seem to bend and flex no matter how easy I landed) oh and that un-steerable tail wheel got me in trouble more then once.
I have been known to take this plane every where I go so hand launching and belly landing suited it better sence I will stop at any open field, vacant lot, camping trip, park, baseball field, etc....to fly it and it's in the back of my 4Runner ready to go at any free moments notice.
With it being a NEW plane though, I would fly with ALL THE GEAR, bombs and working rudder and get the most from it, and as things start to wear a bit (break, fall off, etc...) then stick with what fits you. It's a fun plane with all that stuff hanging on it to and if you take care of it it will last along time.:rolleyes:

slowmover
04-07-2006, 02:18 PM
[quote=Grasshopper;59519]You guys are really frustrating me! Mine just arrived yesterday. I've got a Spektrum DX-6 for it on it its way here now and just ordered 2 2100 mAh 3S 15C lipos and charger this evening. The only thing I have left to get is the ESC. All this talk of how great they fly is really making me want to get out and throw it in the air. Unfortunately it's been really windy here for the last 6 weeks and we're currently under a tornado watch.

It's good to hear that it's that nice flying of a plane. I CAN"T WAIT!!!!!!!!

Tom

So far this is the only foamie thatI have that will handle a little wind 10-15. The people at the park just love this thing. Even the glow flyers love it.

redgiki
04-08-2006, 08:50 AM
So far this is the only foamie thatI have that will handle a little wind 10-15. The people at the park just love this thing. Even the glow flyers love it.
My glow-flyer buddies really enjoy watching it fly, too. I get constant praise for how well it handles, and how pretty it looks in the sky.

As always, I have more advice for newbies:

1. Don't use the wing panels. Yes, the underside of your wing won't look so good, but she'll fly better. Buy grey paint if you must, in order to make the landing gear mount and servo look better. You're creative; I'm sure you can find a way to secure your servo wires without adding ounces of ugly plastic that tend to come off in-flight.
2. If you're moving up from a 2-channel bird, consider building this as elevator/aileron-only, belly-landing ship. You can always add the rudder, landing gear, and bombs later. Or you could follow the opposite advice, above, and build everything on, removing it as it breaks :) The landing gear are just really fragile. If you're a new flyer, you're going to have lots of hard landings, and the gear mounts in this foam just can't take that kind of abuse.
3. Use packing tape or fiberglass to protect the belly pan from scratches. You may also want to consider using clear packing tape along the edges of the canopy foam piece. They tend to crush easily at those points. I'd submit the wing tips and stablizer tips for this list, too, but packing tape looks awful on them (I've tried)... fiberglass is the best option, and that may be too much for a newbie. Clear packing tape is basically unnoticeable on the belly pan.
4. Pry the cowling off the plane very gently when you're unpacking it. The paint will chip off the plastic if it's bent.
5. They are totally serious in the note included with the plane about tugging on your motor mount and hinges. Don't yank hard enough to break the foam, but you really need to steadily, solidly pull on these to attempt to get them to slip out. If a strong, steady tug pulls them out, you can trust the air would do worse.
6. 30-minute epoxy is best for the motor mount stick.
7. Don't follow the motor mount instructions regarding how much to cut off. Measure it yourself, and test-fit the cowling before gluing anything. You may find, as I did, that they ask you to cut off more than you should, and the prop barely clears -- or doesn't clear -- the cowling with your brushless motor attached.
8. A Thunder Power (or equivalent) narrow-form-factor 2100mAh 3S LiPo battery, plus the stock motor, on a Rudder/Aileron ship generally comes out at exactly the right CG without any extra weight. Your mileage may vary, depending on how much glue you use, but it's a light, solid setup that flies very well.
9. The CG can be safely moved back from the indicators on the wing, but you should start at that factory indicator and work your way back slowly. A nose-heavy plane flies poorly; a tail-heavy plane flies once. Remember that you'll need to decrease your elevator throws as you move the CG back.
10. The factory-indicated elevator throws tend to make for rather twitchy elevator response for a beginner. On the other hand, the aileron throws don't seem quite high enough. Adjust to suit your flying style, but remember that on this bird, it flies just fine with fairly minimal throws.
11. If you are up for the time investment, 1/2 oz fiberglass and 2-3 coats of Minwax polyurethane varnish make for a fairly hard finish on critical parts that improve flying and decrease hangar rash. Recommended bits:
* Tips of rudder, elevator, and wings
* Belly pan (if you didn't tape it)
* Wing leading edges
* Canopy hatch edges
If you can fiberglass the whole bird, so much the better, but that will add substantial weight. Your hangar rash will be eliminated, though, and your bird will have a higher top speed.
12. If you use the landing gear, bend them forward so that the axles are under the leading edge of the wing. This will reduce landing gear stress on landing, and also reduce the likelihood of nose-overs. Bend them when they aren't in the plane! If you try to bend them while they are mounted, you'll rip the landing gear mounts out. (Heh, ask me how I know...)
13. The flat-bottom airfoil of this plane is not ideal for long-duration inverted flight. Be cautious flying inverted near the ground.
14. One of the best spots for your brushless ESC is in that hole below your motor mount stick. Just use servo tape to affix it. You'll probably need to extend your battery cables from your ESC to reach your battery through the servo wire hole, but it doesn't block airflow to your battery down there, and it keeps the weight forward of your CG. If you use the factory-indicated location for your ESC, right next to the radio, be sure to do engine-on range checks prior to flying as this location tends to promote interference.
15. Don't plan on using the ailerons as flaperons. The outboard aileron location will tend to cause tip-stalls if used as flaps. A Y-connector works great. This bird slows down enough on landings that you don't really need flaps at all.
16. Roll rates on the full-scale p-47 were pretty slow compared to other contemporary warbirds, and this scale model is no exception. Don't expect 3D roll rates; it's supposed to be a great scale flyer.
17. The foam used for this bird is quite delicate. Handle with care.

That's all for now...

alienx
04-08-2006, 02:26 PM
I have mine done but just can't get it balanced with the clay. I need more weight so I am going to look for some lead strips or something (maybe in Walmart's fishing department).

I did bend the gear forward but I need to take it back some. The forward angle increases when you weight the gear, due to slop in the mount. I have to believe it will cause a failure at the mount even under a decent landing. Plus, I have about 1/2" of prop clearance to the ground. I'd rather take my chances with a nose-over than to collapse the gear, or for certain, to hit the prop on the ground.

I have a scale coming from Target. I think I may hold off until I can see exactly how heavy this thing is. It feels substantially heavier already than my cub, which is supposed to be about 16 ounces.

Crash9
04-08-2006, 05:59 PM
redgiki has it down, what he's recommending is very useful to the newbie. This statment is very true.
9. The CG can be safely moved back from the indicators on the wing, but you should start at that factory indicator and work your way back slowly. A nose-heavy plane flies poorly; a tail-heavy plane flies once. Remember that you'll need to decrease your elevator throws as you move the CG back.

Ron
04-08-2006, 09:46 PM
alienx...go to the nearest tire store, and get some of the stick on balancing weights...they come in small strips that can be removed in 1/4 ounce increments. they're cheap too. they have sticky tape on the back of them and once on will not fall off

alienx
04-08-2006, 09:56 PM
alienx...go to the nearest tire store, and get some of the stick on balancing weights...they come in small strips that can be removed in 1/4 ounce increments. they're cheap too. they have sticky tape on the back of them and once on will not fall off

Never thought of that. Great idea. Thanks.

redgiki
04-09-2006, 06:43 AM
It feels substantially heavier already than my cub, which is supposed to be about 16 ounces.

Flying weight on the P-47D from E-Flite is 22-26 ounces AUW. You can actually go lower than that if you use a slightly smaller LiPo, the Park 400 brushless outrunner (or a geared setup brushless), and elevator/aileron-only without landing gear or the wing covers.

I'm thinking on my next one (yeah, I want another one!) I want to try a pull-pull setup on the elevator and carbon rods for the ailerons, minimal fiberglass, and only A/E controls without landing gear, and pulling out the gear mounts. I bet I can get it down to 20 oz auw...

alienx
04-15-2006, 01:24 AM
I've loved this plane from the first time I saw it on the web at someones hobby site. I just look at it for long periods of time!! The sad fact is that I'm not good enough to fly it yet. But soon enough!

Anyway, it is balanced and ready to fly. It has Park 450 in it like Redgiki's. I'm a little worried about the 17.5 Ap draw on my motor (12 A continuous rating), but everyone else seems to be doing ok.

I balanced mine with 1.25 oz of lead tire balancing weights (stick-on). That was a great tip in this thread from Ron! The only thing I did a little differently was I painted and black-sharpie'd my rudder to get rid of the white foam. You can see it (or not!) in some of the pics. So obviously, I have a workable rudder.

AUW 26 oz. I've been at the top of the range almost exactly with both planes I've built, in spite of the outrunner/lipo set-up in both.

Just wanted to share my excitement!

Andy

firemanbill
04-15-2006, 01:49 AM
Andy, Looks great!!! Keep up that practice an build that nerve up to fly it. I am doing the same thing with my mini funtana. I know the patience and practice on my more docile planes will pay off in the long run.

When you do fly it don't worry if you can't breathe:D . I always hold my breath on my maidens... not intentionally mind you, I figure the battery can't last for more that 20 minutes or so so I should be ok:eek:

alienx
04-15-2006, 03:12 AM
Thanks Bill! We're finally getting some better (calmer) weather here, so I hope to have mine up in a short while too. Just have to work up to it a little more.

That's funny you hold your breath. I've got fingertip grips worn into my TX!! Kinda like John Candy in Planes Trains and Automobiles when they drove between the trucks!

firemanbill
04-15-2006, 03:18 AM
That's EXACLTY how I feel:eek: . great analogy. I had almost forgot about that movie... classic:D

redgiki
04-15-2006, 03:50 AM
IAnyway, it is balanced and ready to fly. It has Park 450 in it like Redgiki's. I'm a little worried about the 17.5 Ap draw on my motor (12 A continuous rating), but everyone else seems to be doing ok.

Andy,

A couple of notes. The Park 450 is rated at 14 continuous amps, not 12. I think my printed documentation was wrong; the online version is correct. The reason none of us are having trouble with 18A on this motor is because there is really good ventilation on the front of this bird. If you're driving a 10x8E prop, you're cooking along at 40-50MPH, and all that air is getting shoved through the cowling and into the motor.

My motor, ESC, and battery are all barely warm after a flight, even if I'm wide-open throttle the whole time. I think if it were a 3D bird, or a helicopter, I'd be more worried about shoving more amps through.

The other thing to look at is that it's rated at 10 cells for 14 amps continuous. 10 cells is 12 volts (nominal). It's *actually* 15 volts on a fresh NiMH or NiCD pack. A 3S LiPo pack is rated at 11.1V nominal, or 14.6V maximum.

Theoretical max draw: 14A * 15V = 210 watts
Our draw: 17.5A * 14.6V = 255 watts

I think when you combine the fact that it's not running that far above spec, with the excellent ventilation provided by the gigantic cowl of the P-47, we're totally good :)

That said, I'm keeping pace with some of the .40-sized glow guys at my field in this bird (admittedly, they're in trainers, but still!). I think I'm going to down-prop to a 10x6 or a 10x4 in the future to get a more scale-like rollout and performance. Maybe even take it down to a 9x7, now that I'm thinking about it. The thrust was great for getting used to the bird, but now that I'm used to her, I don't need the excess power.

As I mentioned in the PM, I'm planning on taking this bird out to fly on the 10x8E on a 2S LiPo. That will put the RPMs down near the stock brushed motor.

Side note: You mentioned in a PM, Alex, that you found your Cessna on an 8x6 to be a handful. You may want to calculate the pitch speed of that prop. You may find that the Cessna actually wanted to move faster than the Jug. No bones about it, though, the Jug is pretty fast for a .20-sized warbird using this powerplant.

alienx
04-15-2006, 04:09 AM
Side note: You mentioned in a PM, Alex, that you found your Cessna on an 8x6 to be a handful. You may want to calculate the pitch speed of that prop. You may find that the Cessna actually wanted to move faster than the Jug. No bones about it, though, the Jug is pretty fast for a .20-sized warbird using this powerplant.

You know, this is all still hard for me to understand. But I'm getting smarter. I guess my Cessna comment was really just a comparison of the same power system in that plane versus the Jug. My cessna weighs 2 oz more, and I had a far "slower" prop on that at 8x6 compared with the 10x8. So given the monster prop and lower weight, I just figured this plane would be too much. I have my Cessna grounded until I my prop order comes from Tower. I bought a bunch of 8 and 9 inch props with pitches in the 3.7 to 4 area. I figure one of them has to be a little milder.

My only Cessna flight was the maiden last week. It ended in a rapid but somewhat gentle disaster as I tried to take some of the motor out and ended up stalling it. But I powered back up to avoid the stall, and it nosed over into the ground under power. I think part of the problem was it was just VERY responsive versus anythig else I'd flown. You get instant control surface movement. My 3 channel RTF is almost a 1/3 that speed across the movement. So it was very twitchy trying to keep the Cessna under control. And that was compounded by the fact that I underestimated the speed and flew in a too small field. I was beat from the start but didn't know it. I'm sure anyone with more experience could have handled the 182 easily. But to me it was a leap.

I'm going to down-pitch my Cessna prop and take some more movement out of the low rates. Then I am going to fly it until I feel good about moving on to the P-47D.

Grasshopper
04-15-2006, 04:10 AM
Hey Redgiki,

You've provided a lot of good info here and on another thread with the P-47. Are you running the stock motor in yours. I'm getting ready to put mine together and was planning on using the stock motor with 11.1 V 3S 2100 mAh 15C lipos. Will I be buying a bunch of motors?

Tom

alienx
04-15-2006, 04:10 AM
That's EXACLTY how I feel:eek: . great analogy. I had almost forgot about that movie... classic:D

That's one of my favorite scenes of all times. Steve Martin had to pull his fingers out of the dashboard, and John Candy had bent the steering wheel almost in half. Definitely a classic!

rjr003
04-15-2006, 03:45 PM
Everyone,
If you need an affordable brushless setup, use the Esskay 400xt (now on sale at Hobby Lobby for around 17 bucks, backorder sale!) in the P-47... flies great AUW is 24 oz. I'm running a 10x4.7 APC prop. using a 3s 2000Mah lipo from gwsexpert. (33 bucks), also using gwsexpert 15 Amp ESC, I think I paid 28 bucks for that. Very affordable setup!! Might not go vertical as a Eflite 450 would make the bird.. but still Fast!! I'm also running it full house and without the gear.

Hope everyone is enjoying the Jug!!

redgiki
04-16-2006, 07:22 AM
You've provided a lot of good info here and on another thread with the P-47. Are you running the stock motor in yours. I'm getting ready to put mine together and was planning on using the stock motor with 11.1 V 3S 2100 mAh 15C lipos. Will I be buying a bunch of motors?
Nope, the "boat anchor" motor is now gracing the front of my Slow Stick. I run it at really low voltage with a great, big prop, and it works great for training newbies.

If you do a proper water break-in on your motor, you should get 50-100 flights out of it on the LiPo. A replacement 480 motor with pinion is $11.00, so you'll have to burn through at least 2-3 motors before your expense matches that of putting in a brushless motor (sans ESC). Considering the first one is included with the kit, you've got nothing to lose if you already own an ESC. Build it stock, fly it till the motor dies, then upgrade. Your amp draw and RPM are well within reason for a brushed 480 on a 3S LiPo. It's basically the same (electrically) as flying on a 9-cell NiMH or NiCD.

A size 400 brushless motor with the correct pinion (just buy a pinion puller and yank it off your stock motor) can be really cheap these days, as mentioned a bit earlier in this thread. The plane flies just fine on a LiPo and the stock brushed motor. I think it's a bit anemic on NiMH and the stock motor, personally, but some people fly that way. If I were to build one with NiMH and the stock motor, I'd forego the rudder and gear, for sure. A 400-sized brushless will fly this plane with authority; I consider the 450 slightly overpowered even at 5000 feet elevation.

I ran the Park 450 on a 2S LiPo this morning with the stock prop, and performance is comparable to that of the stock motor. I had to add nose weight just to keep it from being tail-heavy, though. The wind was high, and the flight was short. It just didn't have much get-up-and-go in that configuration, and wasn't as much fun. I like having reserve power, even though I usually don't use much of it.

The stock motor is MUCH heavier than a brushless setup. If you use a narrow 2100mAh LiPo 3S battery, the stock motor, no gear, and no rudder, your CG should be just about perfect with little or no nose weight. If you're using the Thunder Power batteries, those tend to be a little lighter, so you may be adding a touch of nose weight, but nowhere near the "entire bar of clay" that I had to use with the 450.

I think it's time I did thrust tests on the bird, to show the difference in thrust between 9-cell NiMH, 3S LiPo, stock motor, 450 motor, etc...

alienx
04-17-2006, 03:12 AM
I wanna fly mine. But even with some new props coming, I think I am going to wait a while. I have a 40" Cub coming in the mail this week. So maybe that will be a better next plane. it comes with a brushed motor, so I am hoping it's a mellow "Cub" flyer. We'll see.

But I did get to a flying field near me and talked to some guys Saturday. That might open up some longer-term possibilities. But I still want to be able to go to the local park.

Here's two more shots I took this weekend.

Grasshopper
04-17-2006, 04:13 AM
Thanks Redgiki,

Since I have everything to set it up with the stock motor and 2100 mAh lipos, I think I'll do use you suggest and build it that way. I can always upgrade to brushless later. I was considering building it with the rudder but no gear. I was thinking about going ahead and buying the Eskay 400 XT from Hobby Lobby since it's on sale for $17 (for future upgrade) but was concerned it might be a little underpowered? What do you think?

Any tips on flying it? Any idea on how it will handle compared to my stock PZ P-51? How is it to hand launch?

Thanks for the help,

Tom

redgiki
04-17-2006, 08:11 AM
I was thinking about going ahead and buying the Eskay 400 XT from Hobby Lobby since it's on sale for $17 (for future upgrade) but was concerned it might be a little underpowered? What do you think?
WAY, WAY underpowered on that motor. It's designed for park flyers up to 16 oz, or 3D planes up to 10 oz. A stock E-Flite P-47D is 22-26 ounces. That motor can only handle 10 amps, and is designed for up to maybe 7 NiMH cells (8.4V) or a 2S LiPo (7.4V). You need to target motors which are designed for up to about 20 amps on a 3S LiPo, built more for torque than speed. The recommended Park 400 or 450 outrunners work well, as do other motors designed as .20-.25 replacement engines.

In Outrunners, to spin the prop at the right speed, you want something around 900Kv (really as low as 800 rpm/v and as high as maybe 1100 rpm/v is fine), rated up to around 250 watts. In Inrunners, you want something around 3700-4300Kv with a gearbox that will get you down to around 1000rpm/v, like a 3.3:1 gearbox or so.

So let's look at the field of alternate powerplants for this bird, eh? Obviously, you have the recommended Park 450 and 400 outrunners, and the Park 400 outrunner with a 3.3:1 gearbox. What else is there? Well, I haven't tried these, but they look like they'd fit the requirement:
The Balsa Products BP 2908-10 (http://www.balsapr.com/view.asp?id=V814870&pid=W466625) looks like a good drop-in replacement for a Park 400/450 brushless outrunner. It's in-between the two on Kv, and has some pretty good reviews elsewhere as a cheap, decent motor for .20 glow conversions. Really, any electric motor that has received good reviews for .20-.25 glow conversions probably is in the ballpark. In stock, $47.95.
The Ultrafly B/12/10 (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXKHB5&P=ML) also looks like a good choice. You can already tell I prefer outrunners to inrunners at this size, don't you :) It's rated right at 250 watts, and 1000Kv. Another fine choice. Like with the Park motors, though, you're going to be adding lead to the nose, even if you forego the weight of the rudder mod. (And yes, you can ALWAYS add the rudder later. It's not a big deal.)
The "BM-2915" found by various vendors on eBay might be a good choice. It's really made more for .30-sized aircraft. Reviews on it are also a bit spotty, as it seems that although it's rated at 930kv, it often turns in performance around 650-700Kv. However, since it's a heavier motor, you'll get a bit more power out of it and have to add less nose weight.
The "BM2410-09", also found by several vendors on eBay (most notably World Hobby) is probably a perfect choice of motor if you are looking for "really cheap and works". The Kv is right, particularly since they tend to over-rate these cheap Chinese motors. It says 1100Kv, but I'm guessing it comes in a hundred or more Kv lower than this. At ten bucks plus shipping, you really can't lose. If you buy one, you must provide a review :)Any tips on flying it? Any idea on how it will handle compared to my stock PZ P-51? How is it to hand launch?
You'll find the handling is similar to the PZ P-51, but since it's a bit bigger, heavier, and has more wing area, you'll find runtimes are a little shorter, but that it "floats" on landing much more. Roll rates are considerably slower, unless you really crank up the mechanical linkages on your ailerons. Like the full-scale P-47, it doesn't have much of a tip-stall tendency. The nose just mushes down, and there is not much of a pronounced "stall break" when you hit a stall.

At least, not compared to my ParkZone Typhoon. On my Typhoon, when you stall, you know it instantly: the nose drops sharply. On the ParkZone P-51, you tend to drop a wing a bit pretty sharply. On the P-47d, when you stall, you may just notice that your sink rate has increased quite a bit and you're really cranking back on the elevator to keep the nose up.

I only get the pronounced stall break when I run out of elevator :)

Speaking of elevator, if your transmitter has exponential, I encourage you to dial some in on the elevator. I use about 40%. The bird is sedate on the roll axis, and sedate in yaw, (if you have a rudder) but really twitchy on the elevator with the factory throws. I am sure that the fact I run with the CG behind the marked indicator exacerbates the problem, and in fact I've reduced the mechanical linkages to reduce my elevator throw substantially.

Be sure and use some sort of battery-retention system on this bird! I forgot to attach my Velcro straps yesterday, and my battery slid back a couple of inches in a steep pullout. Trying to land a suddenly tail-heavy P-47 is a challenge, particlarly in a high wind.

Other than that, my standard advice on flying her applies:

Bag the factory wing covers. Use some hinge tape or something to retain your servo wire instead. The wing covers tend to detach in flight, and add unnecessary weight.
Double-check the engine mount and hinges with firm, but gentle tugs. The engine mount tends to come loose easily, as do the aileron hinges.
Fly without the landing gear if you are comfortable with it, and belly-land. She flies much better without the gear, and the mounts and wires are quite weak anyway. I don't recommend attempting to rise off grass with the stock landing gear, particularly on your first flights.
Launches are just like most other hand-launch park fliers: a firm toss, level, and into the wind. I launch at full-throttle; even with the Park 450 motor, there is little tendency to torque on launch. Remember not to try to climb out too fast if you don't have a beefy motor! The real P-47 had a fairly slow climb rate, but could fly at an altitude no other fighter of the era could match.
Remember she gets hangar rash really easily. Tips of the rudder, elevator, and wings tend to get torn up the easiest, followed by the belly pan and edges of the battery compartment cover. Fiberglass is best, but you need to find a way to deal with the difference in finish if you reinforce these areas.


I'd recommend doing several test passes 1-3 mistakes high in preparation for landing. Learn what her stall speed is, and feel what it's like to run out of elevator at low speed. My normal landing approach on grass is like this (partly necessitated by nearby trees at the park where I fly):
An unusually high downwind leg. Maybe 50 feet.
On the turn to final, drop a LOT of altitude. I normally exit the turn to final only 4-6 feet above the ground.
Drop to very low throttle, if any. Sometimes, I just dead-stick it from this point in. I get it about 1 foot above the ground with a bit more speed than I think she needs, and kill the throttle.
As I feel myself running out of elevator, allow it to drop to 3-4 inches, then "flare and flop" for the landing. Of course, by the time I flare-and-flop, I've always already killed the throttle. I prefer to kill it a bit early, and have never broken a prop on a belly landing yet.Good luck. She's a fun bird!

rjr003
04-17-2006, 02:06 PM
Have you actually installed the 400xt in the p47? It has more than ample performance for the p47! This motor handles 3s lipo's just fine, and on the wattmeter stays at around 10 Amps draw at full power. Yes, with this setup, it will not stay vertical forever, but flies just fine for most folks. I've run this motor in three planes with 3s lipo's and nary a problem. Don't believe all the marketing information form the hobby stores!! Remember, their in the game to sell you "more expensive" gear!

Glacier Girl
04-17-2006, 06:21 PM
lot of good advise redgiki.
I left mine pure stock, mechanical wise, I've not had a problem taking off or landing on grass, as long as it wasn't too high. Luckily they mow the soccer fields nice and low.:D

redgiki
04-17-2006, 06:55 PM
Have you actually installed the 400xt in the p47?
Of course not. I've mentioned what I've flown already in this thread: the stock motor and the Park 450. The 450 flies great on 3S, and gets it into the air on 2S with stock-like performance. Numbers:

10A @ 11.1V = 111 watts
Weight of a full-house P-47D (motor's irrelevant here, due to nose weight requirements): 22-26 ounces (1.63 lbs or so)
Watts to Weight: 68 watts per pound

This tells me yeah, if you live near sea level it probably would fly just fine on the motor, and as light as the wing loading is on the P-47D, it probably has very trainer-like characteristics while being capable of mild aerobatics. You'd have solid fifteen-minute flights. It's a solid, if slightly underpowered, choice.

It would be a... dissapointing experience... to try to fly on this motor at 5,000 feet elevation and the steady 10MPH wind 3/4 of the year where I live. I'm open to donations of the motor if someone wants to prove me wrong :) I am working on scale pattern aerobatics with my P-47D, and the 450 gets the job done well enough for that. Even that beefy motor can't keep the bird going vertical at my elevation; I have to prop up to do so, and I'm concerned about ground clearance with an 11-inch prop and landing gear bent forward to forestall tip-overs in grass landings.

You can purchase larger motors for very nearly equal $$ to the 400XT's sale price which will power the P-47D competently within their published specs. If it were possible to save weight and gain performance using the motor, I'd be all over it, but since you have to add nose weight to this bird if you use anything other than the boat-anchor brushed motor, I don't see the point, really.

I've not had a problem taking off or landing on grass, as long as it wasn't too high.
Calgon, Take Me Away!

No, seriously, I wish I could find grass like that out here in Utah. They keep it pretty short at the parks where I fly, but I nose-over on takeoff pretty consistently even with the gear bent forward and my CG behind the marked location. It takes off just fine from asphalt and dirt. My problem may just be that I haven't found a soccer field where the groundskeeper is doing his job!

I wonder how the golf course owners would feel if I started flying off the greens :)

comets8518
04-17-2006, 10:25 PM
I know this is the wrong place to ask but it is going in that direction.

After looking at ebay for the motors suggested, I saw a lot of the TP knockoffs in the 1750kv range.
What type of planes would 1750kv come in handy. I know I have an 850kv on my mosa but I just got it bc it was recommended.
in more detail what makes a certain plane need a certain motor type.
feel free to pm me

redgiki
04-18-2006, 03:34 AM
A Kv rating that high would be useful for lower-voltage applications and smaller direct-drive props. Like if you ran it on 3S LiPos, you'd do well with a 5 or a 6-inch prop... maybe a seven, too. Trying to turn big props, like a 10-incher, would have a pretty severe amp draw unless you kept the voltage down.

RC Crack Head
04-18-2006, 04:44 AM
the more rpm or KV the motor the smaller the prop will have to be to keep the amp draw down. A 1750kv motor will use a small prop 5-8 inch and will make a small plane fly fast. A motor with a KV of 900 will use a prop of about 9-12 inch and will not fly as fast but would be good on a larger plane. I hope this helps. Bill

RC Crack Head
04-18-2006, 05:01 AM
I have one of these plane and they fly like a dream!! I don't know if someone else has already said this or not but the CG that is on the plane is way to fwd. It can come back about 3/4 to 1" and that seems to fly the best for me. I have put LEDs on the plane and I fly at night! it is a blast. I have one in the cock pitt that lights up the pilot, and six white LEDs on each wing, three on top and three on bottom that light up the plane. I have red and green on each wing and a 360% on the tail. I got the red and green LEDs from a downed traffic light and the white ones from a seller on ebay. if any one would like to know how I put them on just email me and I will send you picks of how I did it. Bill
P.S. has any one used a prop saver on this plane? I broke many props before I got a prop saver from AlleRC.com they are great, the only thing that I don't like is that I can't use a spinner with the prop saver.

comets8518
04-18-2006, 07:37 AM
so basically you wouldn't want to run a 1750kv on a plane the size of this p-47 because its too large and you need the thrust from a larger prop diameter?

I'd love to see the how to, maybe you could just create a post and/or pm me with details

redgiki
04-18-2006, 08:07 AM
so basically you wouldn't want to run a 1750kv on a plane the size of this p-47 because its too large and you need the thrust from a larger prop diameter?

Correct. That KV would be ideal for some jet-type pushers with smaller speed props (eight inch on a 3S LiPo is about as big as you'd want to go). A five or six-inch prop would barely clear the cowlling on the P-47D :)

They'll fly the same weight-class of plane, though. I have a delta foamy with an AUW of 22 ounces that flies wonderfully on a 1500Kv motor, 2100mAh 3S Lipo, and 7x6 prop. Plenty of thrust (though not unlimited vertical), reasonable speed (though not a speed demon), and fun to fly.

Glacier Girl
04-18-2006, 02:08 PM
redgiki,
Something else that might help with your ROG's. I set my elevator to max out the throws. Helps hold the tail down, both on take off and landing.
Mixed in a lot of expo so it's not radical in the air.

redgiki
04-18-2006, 03:24 PM
redgiki,
I set my elevator to max out the throws....Mixed in a lot of expo so it's not radical in the air.

Now that's interesting. I mechanically minimized the throw of my elevator because it was too twitchy for my tastes (I have my CG pretty far back from the stock location based on my glide, dive, and climb testing). I'm generally a believer in adjusting linkages so that the plane flies just fine without exponential if it's not a 3D-style "huge throw needed" aircraft.

I may try that, though, and see if keeping back on the elevator until I have some speed fixes my takeoff from grass. Thanks for the tip!

RC Crack Head
04-18-2006, 05:08 PM
Has anyone had trouble getting there hatch off without damage? I found a way that works well for me. I used a thin piece of clear plastic (from a consumer package like a shaver or batteries) and I cut a thin slot in the hatch from forward to back. Push the plastic through the slot and glue it in place. I have only about half inch sticking out and it can hardly be seen and makes almost no wind resistance. To keep it from being pulled out of the foam I bend a 90% in the plastic that is on the inside of the hatch. I hope this helps others who have had this problem. Bill

redgiki
04-18-2006, 11:27 PM
Has anyone had trouble getting there hatch off without damage? ... I used a thin piece of clear plastic...

Bill,

Very cool tip! I've repeatedly crushed the edges of the foam trying to pry the hatch off when it was new. I usually grab the cockpit canopy to try to pull it off these days, but I'm starting to get a little bit of play because of it.

I think I'll try that tip, and add it to my list of suggested mods for new E-Flite P-47D owners :)

jonnyjetprop
04-19-2006, 08:46 PM
The biggest problem I had was getting the cowl of the model when I opened the box. I ended up having to run a knife blade all around to break it free.

John

redgiki
04-23-2006, 07:22 PM
Hope nobody minds me digging up the old thread again. I've discovered something new.

As I've mentioned earlier in this thread, due to extraordinarily easy wing damage I replaced my stock wing with a new one some weeks ago. I fiberglassed the new one with 1/2 oz. fiberglass and MinWax polyurethane varnish, mainly to stop the horrible hangar rash suffered by the foam of this airplane. As a matter of fact, I just grabbed the old wing by the wingtip to pull it out of storage and look at it when starting the repair mentioned in this post... and the wingtip broke off in my hand, right at the panel line! Oy!

As I've mentioned, fiberglassing the wing dramatically reduces drag and seems to increase the top speed substantially. Yesterday I was at a club event, flying over the salt flats. I was in the air with five other airplanes, and since they were all much larger (.40-1.20 sized), I was kind of fighting to stay in the pattern yet stay out of their way. With the Park 450 motor, this plane will keep up with .40-sized trainers, but not overpowered nitro warbirds!

It was becoming quite a warm day. About 80 degrees. This was my winter daily-driver, so warm weather is kind of a new phenomenon with it. I noticed about six minutes into my flight (mostly full-throttle, due to flying with the big dogs) that I was experiencing some weirdness in rolls. It just didn't have the authority I was used to. It's never been a snappy roller -- and won't ever be since, IMHO, neither was the original -- but this was unusual.

Landed her, and I found that the foam on which the aileron control horns had attached had come almost completely off! That would have been bad in flight. One aileron was a little worse than the other. I had not noticed any aileron play in previous pre-flights, so I'm assuming the damage was mostly made on this one high-speed run.

(High-speed being relative, of course. Several glow guys came over after I landed and commented that they really liked how well my electric flew, and asked what it was. Ahh, the start of busy flying season. They're not real men, they're just cupcakes! How come I didn't see them down there all winter long, eh?)

When I'd fiberglass the ailerons, I had left the control horns on and not fiberglassed that area. In retrospect, that was a stupid move :) But I thought it would save some time...

I think that the speeds at which the 450 motor can push this bird -- particularly in a dive -- are beyond the strength of the thin foam which the aileron control horns plug into. My guess is that I was starting to experience some flutter in the control horn linkage, as they stock E-Flite connections have a good deal of play, both at the servo and at the control horn.

And, to be fair, I'm certain the aileron weighs more than it did, since it's covered in fiberglass to match the wing. Heavier control surfaces == more damage due to flutter.

Any ideas on how I can firm up this linkage to prevent future damage? I've repaired the damage with foam-safe CA, and it seems sound. However, I'm going to patch some fiberglass onto both sides so that the control horn mounting area is at least as strong as the rest of the aileron.

The only idea I've seen which seems to have much credence in reducing play due to oversize holes in linkages is to put epoxy over the hole, and then Vaseline your linkage and put it through the hole/epoxy combination (it's supposed to make the clevis and rod connections tighter). That seems somewhat messy and not likely to last, so I'm looking for other options before I fly my P-47 again.

She's my daily driver (along with my Wild Wing), and it's beautiful, windless, and sunny today! Argh! Fixing stuff when I should be flying!

afpe45
04-23-2006, 07:45 PM
@redgiki.
I always throw stock linkages out and replace with ball joints(the type used on helis)

afpe45.

viking
04-24-2006, 01:35 AM
Just bought this bird 4 days ago. Great warbird by all standards. Gear had to go after 5 flights. Made a skid out of carbon fiber and painted to match.

redgiki
04-24-2006, 04:52 AM
Great warbird by all standards... Made a skid out of carbon fiber and painted to match.
I thouroughly agree. I fiberglassed the belly pan, rather than doing a carbon-fiber skid, but there's more than one way to skin a cat!

Be cautious for your wingtips and elevator tips in belly-landings, though, and inspect them for damage after every landing. All it takes is an errant blade of grass, it seems, for the foam to break at the panel lines. A little glue and it's back in the air, though.

Grasshopper
04-24-2006, 05:20 AM
Hey redgiki,

What kind of glue are you using to fix the foam?

redgiki
04-25-2006, 08:47 AM
What kind of glue are you using to fix the foam?
I just used foam-safe CA. I tried using epoxy and microballoons on my previous wing, and, well, that was part of the reason I bought a new wing. The styrofoam (EPS foam) is way softer than the epoxy + microballoons, so sanding it just resulted in the epoxy mixture yanking more chunks of foam out. Not pretty.

Foam-safe CA hardened it up nicely. I just used the aileron pushrods to pin the torn-out chunk in place, and it seems stronger than when it was new. I'm still going to do a patch job with a few small pieces of fiberglass and Minwax polyurethane varnish.

After looking at my repair so far, I think it's pretty certain that a combination of flutter, plus having a heavier surface due to fiberglassing, were what caused the failure. Had I not glassed it, the plane would have been slower (less flutter), and the surface lighter (less flutter). If I were to do it over again, I would remove the control horn and fiberglass the entire aileron.

Having it hangared for a few days has actually been kind of nice, in a way; I'm flying less, and have more time in my workshop (doing a few miscellaneous repairs on this bird, firming up my motor mount, trying out different wheels, wires, and pushrods, etc.). I finished my sailplane tonight, and am looking forward to finishing a .40-sized SPAD trainer which has been sitting on my shelf since last season. The rest of the fleet's in fighting trim, save one wrecked Stryker that I'm still ambivalent about fixing...

Grasshopper
04-26-2006, 05:51 AM
Thanks,

I'm sure at some point I'll be needing to glue mine too.

redgiki
04-26-2006, 09:55 AM
I'm sure at some point I'll be needing to glue mine too.

If it is your "daily driver" plane (like it is mine), one which goes to the field with you just about every time... yeah. I've logged at least 3-6 flights a week every week on it since February, and probably twenty-five flights since I replaced the wing. Curiously, the old wing showed no sign of hard use on the control horn foam attachment area, which led to my conclusion that fiberglassing the wing, but leaving out this on high-stress area, had led directly to my failure.

Grasshopper
04-26-2006, 04:44 PM
I haven't even started putting it together yet. I've got everything for it now but just haven't had the time. I've learned a lot of good info from this thread and I'm really kind of glad I hadn't started yet because of all the good tips here. I can't wait to get it in the air. I'm still tossing around whether or not to go ahead and go brushless from the start or get it going with the stock motor. Man, you're a late nighter aren't you? All of your posts are in the middle of the night.

redgiki
04-26-2006, 08:02 PM
Man, you're a late nighter aren't you? All of your posts are in the middle of the night.

I work nights, US MDT. I'm up late today because of a meeting :) I synchronize my clock to Bangalore, India time, because those are the users I support on my job.

The plus side of my schedule? I can go to the flying field on weekday mornings a lot and get in 2-3 hours of flying before bedtime around noon!