GREAT tip! I will have to try that! I have a replacement cowling, wing, and elevator coming due to my aforementioned wear-and-tear (non-crash) damage.

I don't have the machine in front of me, but I seem to recall that mine was 26oz. Every ounce counts on this bird, so I went with HS-55 servos all around, took the casing off my Hitec Supreme receiver to shave a few grams, etc. I use the stock prop and a Master Airscrew 10x8E Electric Only prop.

I want to try an 11x7 or 11x6 as well; the P-47 flies a bit faster than I'd like (I like scale speeds) at full throttle, and I'd like to go with a bit more thrust than speed due to my elevation (5000 feet).

The factory-listed CG is slightly ahead of where I think it should be. Nose-heaviness will hurt your upline significantly. What you want to do to figure this out is go full-throttle and point your bird at a 45-degree angle. Watch what it does. It should SLOWLY nose-down to horizontal from a 45 if it's balanced correctly. If it noses down quickly, you've probably got a nose-heavy CG. If the tail swings forward and it wants to climb vertically, you're probably tail-heavy.

Note that thrust angles can cause the same behavior, so if possible try this with varying throttle levels. You'll figure it out.

IMHO, you won't get "vertical" performance on a Park 450 with the stock prop unless you live at sea level (maybe; not even sure on that). It will hold a solid 45 degree climb on the 450 and a TP2100 3S1P LiPo. I fly with a heavier Master Airscrew 10x8E "Electric Only" prop most times. It's slightly more "thrusty" with a lower top speed than the E-flite 10x8E. Because the prop is so big, even the slightest imbalance is exaggerated and will rob power.

Compared to a 3D flyer, like my ParkZone Typhoon, the P-47 IS sluggish! It has tiny ailerons (comparatively), and a far worse thrust-to-weight. One thing I've noticed is that the Park 450 can really build up a head of steam. It goes fast if you just keep it level at full throttle. I'm thinking of going up to a 12x6 or a 11x7 prop to try to get more thrust and less speed. The 12x6 may be a problem with the stock landing gear, but I think an 11x7 or 11x7 will fit just fine.

Be very careful with that vibration. As mentioned, the shaft mount for the P-47 is only hot-glued in by default, and tends to become really wobbly. Try running your motor with the prop off, and lightly press a finger against the naked shaft with the motor running at the usual "bad vibration" point. Can you feel a little vibration with your finger? You may have bent the prop shaft on you 450, and this will rob a lot of power and suck down more amps.

The 450's aluminum shaft is quite soft. One good nose-over, like the one my buddy did in the grass, can bend it enough to cause serious power problems. Put a new shaft on order with your LHS as a spare, regardless. They're only 4 bucks. Once I get my replacement in, I'm going to try straightening my old one using the c-clamp method.

The 450 will zip the P-47 around the field at a very nice clip and enable beautiful faster-than-scale aerobatics with very large loops. But with the stock prop, it is by no means a vertical performer. You'll need to upgrade props to get vertical out of it. I'm guessing a 12x5 or 12x6 will almost certainly do it, but I'm going to try an 11x7 first since I run with gear. If I were landing gearless in grass, I'd probably go straight to a 12-inch prop.

I'm not sure on the 480, as I don't have one, but I hear that the amp draw goes up precipitously with the stock prop. I'm trying to find the thread where someone tried the 10x8E on the 480, and the runtime was really low.

The Park 450 enables a solid 45 degree climb from minimal speed. A light toss at full throttle works great for a launch. However, trying to gun it straight up on this motor is a recipe for disappointment

It flies much better without the gear. I'd recommend packing tape (or fiberglassing) just behind the wing set screw on the wing support panel to preserve the finish, and the same treatment for the wing leading edge through past the fake landing lights on the wings. If the grass is long-ish, it will tear up the leading edge and the area of wing just outside the ailerons. The foam is very thin there.

Remember that packing tape is a PERMANENT improvement on this bird. If you try to pull it off, man, does it ever get ugly fast. I have a new wing on order for this reason, due to my attempts to keep the wing panels from pulling out in flight over and over and over again despite the secure double-sided tape jobs I've done. That foam is just slippery, I guess.

That said, the P-47 coasts in nicely to an easy flare-and-flop landing without gear. You can't maintain a "high alpha" approach like the Stryker, but it works. Word of warning, though: Don't try to do flaperons using those little ailerons a the tips. They just make you tip-stall.

For landing in grass, I make my turn to final rather high. I gauge my distance, and usually nose it down a lot and dead-stick it. If I need to extend my glide path, I throttle up some. I can usually just flop it at my feet now, and it skids for a total of maybe three to six inches. Long grass and weeds, however, tear it up something awful. I don't recommend landing in tall, dry weeds.

It depends on your build. With the full-house build including landing gear, approaches must be rather quick, and comparable to the landings I've seen on the PZ P-51. With just aileron and elevator controls, no landing gear, and a LiPo lighter than the 2100mAh, it's a real floater and coasts in much slower.

The E-flite P-47, like its full-scale counterpart, is a "nicer" flyer than the P-51. It flies slower and is less aerobatic, but it's much more forgiving. If you bring it in too slowly, it doesn't tend to tip stall, but instead the nose just mushes down. Like most low-wing warbirds, though, you really want to keep your speed up. I dead-stick land it most times, but that's only because I'm used to aggressive, high-speed dead-stick landings. The sink rate on most warbirds sans power is alarming the first few times!

Suffice to say, it doesn't float in nearly like a Stryker at high alpha. But it's very controllable; if you've landed a Stryker, just remember to keep this one going a little faster to land it.

In the stock configuration, with gear, you have to be very careful of your approach vector, though. Once the tailwheel is planted you have zero control over direction of the plane other than very very slight rudder (at speed; once you slow down, that's gone too) and throttle to touch-and-go. This is why I usually recommend a "wheels landing" if using gear on the P-47 and landing on asphalt, in order to keep that tailwheel off the tarmac as long as possible; if you're going to land on grass, then I recommend a hand-launch and a slow "flare and flop" landing.

KVs (RPMS per volt) are WAY too high on the BP-21. The Park 450 is an 890Kv motor, rated for 12A at 11.1V. The BP-21 is 1750Kv, rated for max 13.1A @ 11.1V. I strongly suspect you'd burn it out trying to swing a 10x8E at 11.1V. You need a lower KV, "thrustier" motor. If you geared the BP-21 down 2:1, though, it should work fine.

If it's just that the Park 450 is too expensive, the BP9Y and BP2908-10 outrunners look like they may swing the stock prop well. I know the 2908-10 would do just fine (and have a higher top speed and amp draw than the 450), but the 9Y may be a stretch.

--
redgiki
- - - -
Thought for the moment:
As in certain cults it is possible to kill a process if you know its true name.
-- Ken Thompson and Dennis M. Ritchie

The 450's aluminum shaft is quite soft

==============
Not sure I follow this one? The 450 outrunner uses a 3.2mm hardened steel shaft that is very durable (and replaceable).

FWIW, no hot glue is used on the P-47 at the factory. It is a different type of glue. Room for improvement has been noted in motor mount and LG gluing, and future production should be improved.

David

maiden flight report rudder mod brushless outrunner 3cell 2100mah lipo flys like a tf bird rock stable wind 15-20mph no problems. the only bad thing is the moter stick isnt to secure and even after foam safe ca its loose.

redgiki :

Wow!
I agree with about 25% of what you wrote. Guess I take my vidcam to the field tomorrow ( weather permitting ) and roll some footage of me screaming across the deck @ 3ft then climbing straight up or Doing a ROG an climbing out @ 75 to 80*.
Yes I do live near sea level.


Maybe High Altitude is effecting more than your flying

Great Response, just don't agree with most of it.

sluggish! i flew at 40 % power and climbed like a bat ! full power havent tried it yet

GREAT tip! I will have to try that! I have a replacement cowling, wing, and elevator coming due to my aforementioned wear-and-tear (non-crash) damage.

I don't have the machine in front of me, but I seem to recall that mine was 26oz. Every ounce counts on this bird, so I went with HS-55 servos all aro
und, took the casing off my Hitec Supreme receiver to shave a few grams, etc. I use the stock prop and a Master Airscrew 10x8E Electric Only prop.
I want to try an 11x7 or 11x6 as well; the P-47 flies a bit faster than I'd like (I like scale speeds) at full throttle, and I'd like to go with a bit more thrust than speed due to my elevation (5000 feet).

The factory-listed CG is slightly ahead of where I think it should be. Nose-heaviness will hurt your upline significantly. What you want to do to figure this out is go full-throttle and point your bird at a 45-degree angle. Watch what it does. It should SLOWLY nose-down to horizontal from a 45 if it's balanced correctly. If it noses down quickly, you've probably got a nose-heavy CG. If the tail swings forward and it wants to climb vertically, you're probably tail-heavy.

Note that thrust angles can cause the same behavior, so if possible try this with varying throttle levels. You'll figure it out.

IMHO, you won't get "vertical" performance on a Park 450 with the stock prop unless you live at sea level (maybe; not even sure on that). It will hold a solid 45 degree climb on the 450 and a TP2100 3S1P LiPo. I fly with a heavier Master Airscrew 10x8E "Electric Only" prop most times. It's slightly more "thrusty" with a lower top speed than the E-flite 10x8E. Because the prop is so big, even the slightest imbalance is exaggerated and will rob power.

Compared to a 3D flyer, like my ParkZone Typhoon, the P-47 IS sluggish! It has tiny ailerons (comparatively), and a far worse thrust-to-weight. One thing I've noticed is that the Park 450 can really build up a head of steam. It goes fast if you just keep it level at full throttle. I'm thinking of going up to a 12x6 or a 11x7 prop to try to get more thrust and less speed. The 12x6 may be a problem with the stock landing gear, but I think an 11x7 or 11x7 will fit just fine.

Be very careful with that vibration. As mentioned, the shaft mount for the P-47 is only hot-glued in by default, and tends to become really wobbly. Try running your motor with the prop off, and lightly press a finger against the naked shaft with the motor running at the usual "bad vibration" point. Can you feel a little vibration with your finger? You may have bent the prop shaft on you 450, and this will rob a lot of power and suck down more amps.

The 450's aluminum shaft is quite soft. One good nose-over, like the one my buddy did in the grass, can bend it enough to cause serious power problems. Put a new shaft on order with your LHS as a spare, regardless. They're only 4 bucks. Once I get my replacement in, I'm going to try straightening my old one using the c-clamp method.

The 450 will zip the P-47 around the field at a very nice clip and enable beautiful faster-than-scale aerobatics with very large loops. But with the stock prop, it is by no means a vertical performer. You'll need to upgrade props to get vertical out of it. I'm guessing a 12x5 or 12x6 will almost certainly do it, but I'm going to try an 11x7 first since I run with gear. If I were landing gearless in grass, I'd probably go straight to a 12-inch prop.

I'm not sure on the 480, as I don't have one, but I hear that the amp draw goes up precipitously with the stock prop. I'm trying to find the thread where someone tried the 10x8E on the 480, and the runtime was really low.

The Park 450 enables a solid 45 degree climb from minimal speed. A light toss at full throttle works great for a launch. However, trying to gun it straight up on this motor is a recipe for disappointment

It flies much better without the gear. I'd recommend packing tape (or fiberglassing) just behind the wing set screw on the wing support panel to preserve the finish, and the same treatment for the wing leading edge through past the fake landing lights on the wings. If the grass is long-ish, it will tear up the leading edge and the area of wing just outside the ailerons. The foam is very thin there.

Remember that packing tape is a PERMANENT improvement on this bird. If you try to pull it off, man, does it ever get ugly fast. I have a new wing on order for this reason, due to my attempts to keep the wing panels from pulling out in flight over and over and over again despite the secure double-sided tape jobs I've done. That foam is just slippery, I guess.

That said, the P-47 coasts in nicely to an easy flare-and-flop landing without gear. You can't maintain a "high alpha" approach like the Stryker, but it works. Word of warning, though: Don't try to do flaperons using those little ailerons a the tips. They just make you tip-stall.

For landing in grass, I make my turn to final rather high. I gauge my distance, and usually nose it down a lot and dead-stick it. If I need to extend my glide path, I throttle up some. I can usually just flop it at my feet now, and it skids for a total of maybe three to six inches. Long grass and weeds, however, tear it up something awful. I don't recommend landing in tall, dry weeds.

It depends on your build. With the full-house build including landing gear, approaches must be rather quick, and comparable to the landings I've seen on the PZ P-51. With just aileron and elevator controls, no landing gear, and a LiPo lighter than the 2100mAh, it's a real floater and coasts in much slower.

The E-flite P-47, like its full-scale counterpart, is a "nicer" flyer than the P-51. It flies slower and is less aerobatic, but it's much more forgiving. If you bring it in too slowly, it doesn't tend to tip stall, but instead the nose just mushes down. Like most low-wing warbirds, though, you really want to keep your speed up. I dead-stick land it most times, but that's only because I'm used to aggressive, high-speed dead-stick landings. The sink rate on most warbirds sans power is alarming the first few times!

Suffice to say, it doesn't float in nearly like a Stryker at high alpha. But it's very controllable; if you've landed a Stryker, just remember to keep this one going a little faster to land it.

In the stock configuration, with gear, you have to be very careful of your approach vector, though. Once the tailwheel is planted you have zero control over direction of the plane other than very very slight rudder (at speed; once you slow down, that's gone too) and throttle to touch-and-go. This is why I usually recommend a "wheels landing" if using gear on the P-47 and landing on asphalt, in order to keep that tailwheel off the tarmac as long as possible; if you're going to land on grass, then I recommend a hand-launch and a slow "flare and flop" landing.

KVs (RPMS per volt) are WAY too high on the BP-21. The Park 450 is an 890Kv motor, rated for 12A at 11.1V. The BP-21 is 1750Kv, rated for max 13.1A @ 11.1V. I strongly suspect you'd burn it out trying to swing a 10x8E at 11.1V. You need a lower KV, "thrustier" motor. If you geared the BP-21 down 2:1, though, it should work fine.

If it's just that the Park 450 is too expensive, the BP9Y and BP2908-10 outrunners look like they may swing the stock prop well. I know the 2908-10 would do just fine (and have a higher top speed and amp draw than the 450), but the 9Y may be a stretch.

--
redgiki
- - - -
Thought for the moment:
As in certain cults it is possible to kill a process if you know its true name.
-- Ken Thompson and Dennis M. Ritchie

[/quote]

vfv

Yep same here. Mine glides in very well.

Great post stoneenforcer.

We've had bad weather here recently so I haven't been able to fly yet with different props, etc. But I did break down and buy a Park 480 motor and an amp meter.

At wot this setup with the 11x8E prop pulls 29amps. My auw is a hefty 29 oz. I was able to remove some of the lead weight in the nose and I may be able to remove a bit more after test flying. Don't know for sure why my auw is so high. Probably the added weight of the 40A esc and I did switch to larger wheels. Otherwise, I have the standard full house setup with HS-55's, Electron 6 receiver, and TP 2100 Prolites.

I'll report back when I have flown with the Park 480.

I tried out larger wheels for short time. The weight difference to landing help trade off was nil for me so I'm sticking with stock wheels. Also have you thought about this RX [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXGZT0&P=7]Hitec HFS-05MS [/link] instead of the big clunky electron 6?
Will save a few grams, every bit helps. I used O5MS in all my parkflyers 1 mile range and the 5th channel (6) can be setup for flaps,flaparons. Save you some dollars too.

Good Luck