View Full Version : After "aarrggh, trying to get parkzone decathlon to fly" here's an update...
10-18-2005, 11:06 AM
Time for an update...
So after the last outing that involved the plane not really getting of the ground for any length of time, I scoured the net for ways to improve it's power to weight ratio. The micro fireball motor which seems to be the motor of choice isn't available from ANYONE on this side of the pond - yes i'm English - and so I've ordered one from an ebay.com supplier that was happy to ship internationally... and thanks to the amazing exchange rate at the moment it was damn cheap! yippie! of course i have to wait for it to turn up tho...
The other mod that seems to be a matter of course is changing the prop. I bought an 8X6 and a 9X4.7. I also bought a prop saver that holds the prop on with an O-ring and allows deflection of the prop up to about 20 degrees from straight upon impact on one blade... a good buy :) I also removed the right and down thrust from the bulkhead leaving the built in angle on the gearbox and removed the nut fastened within the cowling.
As the motor is still in transit, but I wanted to increase lift and reduce wing loading I added flaps to one of my sets of wings. These were made from parts of the tailplane that got damaged when the plane was shipped to me. Each flap is one side of the horizontal part of the tail with the moveable elevator cut off. I peeled the covering off and glued them to the underside of the trailing edge of the wing along the line of the back of the sticker there, far enough out to avoid conflicting with the rubber bands to hold the wing on, but as close as possible to the fuselage. These were then covered in clear parcel tape top and bottom continuing a centimetre pass them onto the wing to make sure they stayed put and inline with each-other. I didn't try to add a curve to them, they pointed down at an angle set by the centimetre of the trailing edge that they were glued to.
If I manage to attach a pic or two, you'll be able to see them in the one with me holding the plane. After the first flight i actually cut them down from what you see and their trailing edges were straight for all further flights.
Suitably armed with two battery packs, new gearbox internals installed (i bent the prop shaft last time), prop saver and 8X6 prop on off we go sunday night to the local football (that'll be soccer to you) field.
Quite a difference! climbs properly but needed a lot more down elevator added into the pushrod to make level flight possible without holding the stick. Turns left to start with, ended up adding a lot of right turn to the pushrod to make straight flight without holding the stick (more on that later who those who have guessed).
This is fun! plane seems to fly suitably well, but right turns are a bit of an effort and left turns turn in far more quickly and lead rapidly into the tip stall spin of death, ahem.
Plane gets "landed heavily" (read crashed) several times because of this left hand turn of doom, but survives all without anything more than an increasingly tatty front of fuselage and increasingly silly under carriage angles... actually come to think of it, a crumpled wing tip too. Prop stays straight, prop-saver was a very good buy :D
Finally towards the end of the first battery, a heavy landing (crash) results in the plane flipping over and breaking the thin bit of elevator between the two sides. Damn, I was enjoying that.
Home and the silly amount of right rudder trimmed in traced to a warped wing, should have check that before... d'oh. Will use the paint stripper idea, thank you lomcevak.
I am definately still a complete beginner, but starting to get the hang of it, i'm sure i'll do a lot better without a warped wing. The super decathlon flys a LOT better than stock with the addition of flaps and the other prop, instead of struggling to get off the ground (figuratively speaking, i've always hand-launched) I had no problem climbing really quickly and it flew out of my hand straight away since the flaps had reduced it's stall speed. If you're having trouble learning, I highly recommend this course of action. Of course, removing them might be an issue, but as I bought my three planes second hand and the decathlon came with 4 wings, I didn't mind messing with one set :)
So, progress! I don't consider myself to have maidened it properly yet, because every flight ended in a prop to earth interface. When I fly and then make an attempt at landing as opposed to just taking evasive action at the last second, then i'll be there ;)
Oh, used high rate all the time, useful bit of extra throw to get out of trouble... And found out last night that I actually managed to bend the prop shaft again, but only very slightly... I reckon i'll be able to bend it back in a vice no problem. Learning to shut off the throttle completely when it's definately going to hit has also saved the gearbox plastic gear, something I ripped several teeth out of last time.
Have PC power unit and have identified all the wires, just need to buy some connectors and things and will make powersupply i can use inside.
buy more gearbox internals, i'm going to bend more i can tell.
fill front of fuselage with construction filler foam, as suggested by someone who owns the mustang on another forum, to improve the crash-a-bility. The front of the fuse is rapidly turning to mush, but the rest of it is fine... will buy new fuse when i've got the hang of it...
charge batteries, wait for calm weather... go flying :)
take photos when it's a bit lighter...
Cheers for all suggestions... will let you know how it's progresses :D
Ok, can't get photos to work. Have them on my PC saved at bitmaps so they're small but the upload attachments button comes back with "invalid post supplied" when i try to attach them. suggestions?
10-18-2005, 12:53 PM
ive got alot of experience with this plane, as my bro in law just bought it to ''get started''.
for a trainer plane its got to be one of the hardest planes ive ever flown.
nasty tip stall, slow roll and reaction from rudder, almost uncontrollable in any kind of wind.
if you are dejected or at all in dismay about your flying, and you are learning on this plane, dont be. it is certainly not indicative of an easy to fly learning plane thats for sure.
even so called ''advanced'' or ''expert'' planes are easier to fly than this.
10-18-2005, 03:42 PM
Yes, i'm quite concerned by the ease with which it will tip stall... is there a way of counteracting this that anyone can think of? The wings have some washout built into them, should i try adding a bit more when I play around de-warping that wing? Maybe a bit more dihedral so that when the struts are connected on they're under a bit more tension which might pull the leading edge down more than the front leading to more washout?
I bought a job lot and also got a parkzone mustang and an F-27 stryker... since you say the decathlon is hard to fly, should i just go ahead and thrown the mustang skywards? i was planning to get to grips with the decathlon first...
10-19-2005, 01:15 AM
Best way to stay away from the tip stalls is to keep your speed up and do your "aerobatics" at a high altitude until you get use to how the Decathlon reacts when it stalls .. once you get the feel for its instablilities it actually makes it fun to fly
and yes i have one .. er "had" .. its been retired after 200+ flights and several motors,wings, fuses etc. etc. :)
also .. once you have mastered the PZ Decatlon your pretty much ready for anything .. as was said in an earlier post its not an easy plane to fly. Actually i found it to be the least beginner friendly three channel High Wing Plane ive ever flown. it flys nothing like the PZ J3 Cub, the Cub being the "MUCH" more beginner friendly of the two.
as for landing it .. you have more than likely noticed the the Decathlon likes a high landing speed... don't try and slow her down to much or it gets real ugly real quickly :).. what always seemed to work the best for me was to get it on final approach cut the motor at about 15 feet above the ground she will drop her nose .. let it .. wait until its about 3 to 4 feet off the ground start adding some up elevator ( gently ) to get her to level out and then just let her settle onto the ground .. the landing speed will be high but it should be a pretty soft touch down and roll out..
10-19-2005, 05:36 AM
I don't believe that Parkzone suggets this as a beginner plane. I belive they recommend their J3 Cub or Slo-V for beginners. This is the "next step" plane in their line.
Something like an Aerobird, an T-Hawk or an Easy Star would be much easier as a first trainer.
10-19-2005, 06:38 AM
ive asked this numerous times of my bro, due to how difficult it is to fly.
he tells me everytime that the box says ''beginner''.
10-19-2005, 09:39 AM
I am sure he he right, but it doesn't say beginner anywhere on the product page of the Parkzone web site, so I did not think it was promoted as a beginner plane.
I looked at the J3 Cub and the Slo-V as well and none of them talk about being beginner planes. All talk about moving up from a HobbyZone plane. Interesting.
I have looked at the web site for this plane before, and interperted this as meaning it was considered a "second" plane. this was taken from this web site:
Among the Super Decathlon’s fun features is ParkZone’s exclusive Mode Change Flight Control software, which couples elevator and rudder for those pilots who are moving up from a HobbyZone® airplane so they can smoothly adjust to using pitch, especially if they learned on a 2-channel plane. More experienced flyers can enjoy fully independent elevator and rudder control with a quick mode change to "Expert Mode". Learning to fly mild aerobatic maneuvers with the Super Decathlon smooths the transition to more advanced aerobatic models later on. The docile flight characteristics provide park-flying enthusiasts with the ability to choose the skill level that best suits their needs.
The Super Decathlon RTF comes complete with no additional purchase necessary. Included are a reusable 27MHz radio system with a receiver/speed control module and separate 5-wire servo motors, one-piece wing with struts, gear-reduced 370 motor with a large prop, aluminum landing gear and wheel pants, a 1.2A variable rate DC peak field charger, and everything else needed for quick, easy fun—even the batteries for the transmitter.
For HobbyZone fanatics looking for a realistic-looking scale plane to develop their flying skills, or experienced pilots wanting a quick Sunday scale fix, the ParkZone Super Decathlon RTF is just the ticket.
10-19-2005, 10:42 AM
good post Ed.i dont want to bag the manufacturer, but its a toughy to fly thats for sure.to avoid the tip stalls, id perhaps look at tweaking in some washout on the tips.Tim.
10-19-2005, 11:52 AM
Ok, since i have spare wings... I will try and add some more washout to the tips when i have a play with the hot air paint stripper.
Will let you know :)
10-19-2005, 02:05 PM
A couple of thoughts from someone who has never flown this particular plane but has hundreds of flights on other hobbyzone and parkzone planes.
Generally I have found that their planes all fly well, stock, right out of the box IF you follow the directions. I have had numerous newbies bring me Aerobirds, Slo-Vs, Commanders, a Piper Cub, Xtreme, Stryker, all saying that " this piece of junk won't fly".
BTW, I have never flown your particular model. Nor have I flown any of them from the ground as I don't have a runway. I am on a grass field. I always hand launch them.
First I check all the parts, check all the surfaces, makes sure the battery is charged and do a radio check. I often find something out of adjustment or simply not working right. I adjust the adjustable and send the others back to the hobby shop for exchange.
Once all is set, I ask for permission to fly it. All but one flew perfectly right on the spot. No problems, no issues, nothing. Each time I have a shocked owner.
Now, I am not saying you are one of these, but by sharing my observations maybe something will click.
Hand Launches -
Too Steep, Tipped wings, no push or not into the wind!
When the unhappy pilot tried to launch, in each problem case, the pilot was throwing the plane up at a 30 degree or greater angle, or he was throwing it with the plane tipped 30 digress or more left or right causing the plane to go into an immediate turn before it has enough speed to fly. In some cases they let go of the plane with almost no push at all. The plane would stall and crash.
Others gave a good launch, then go full up elevator, and watch it fall from the air!
I launched it straight out, wings level, solid push and KEPT MY HANDS OFF THE ELEVATOR! The planes flew, lost about 25% of their altitude, then started to climb. Often I do this with my hands spread out wide so they can see that I am doing NOTHING! I may touch the rudder to just keep them going straight and level. Up they go! No elevator input!
Take Off and Land into the Wind
Aside from the need for a level solid flat throw into the wind, the key lesson is that the elevator does NOT make the plane go up. It changes the attitude of the wing. If the plane is not flying fast enough, this will cause a stall, the plane will lose lift and crash.
Straight out, and level, directly into the wind, full power with a good solid push, like throwing darts at the pub!
If you are trying to ROG, rise off the ground, DON'T USE THE ELEVATOR to get the plane in the air. It should leave the ground on its own when it reaches sufficient speed. Perhaps 10% elevator after about 5 seconds of roll out just to coax it up, but if it won't lift on its own then you have a trim problem or something else is wrong.
We can go on from there, but my observation is that the hobbyzone and parkzone planes, if functioning properly, fly very well right out of the box.
10-19-2005, 02:06 PM
Whether you have a coach or you are trying to learn to fly on your own, you
will need to be mindful of these six areas if you are going to become a
successful RC pilot. After two years of working with new flyers at our club,
and coaching flyers on the forums, there are a few things I have seen as the
key areas to stress for new pilots. Some get it right away and some have to
work at it. They are in no particular order because they all have to be
learned to be successful.
1) Wind - The single biggest cause of crashes that I have observed has been
insistence upon flying in too much wind. If you are under an instructor's
control or on a buddy box, then follow their advice, but if you are starting
out and tying to learn on your own, regardless of the model, I recommend dead
calm to 3 MPH for the slow stick and tiger moth type planes. Under 5 MPH for
all others. That includes gusts. An experienced pilot can handle more. It
is the pilot, more than the plane, that determines how much wind can be
The wind was around 10 mph steady with gusts to 12. That was strong enough
that some of the experienced pilots flying three and four channel small
electric planes chose not to launch their electrics. This new flyer insisted
that he wanted to try his two and three channel parkflyers. Crash, Crash,
Crash - Three planes in pieces. He just would not listen. Sometimes you just
have to let them crash. There is no other way to get them to understand.
Many parkflyers can be flown in higher winds by AN EXPERIENCED PILOT. I
have flown my Aerobird in 18 mph wind (clocked speed) but it is quite exciting
trying to land it.
Always keep the plane up wind from you. There is no reason for a new flyer to
have the plane downwind EVER!
2) Orientation - Knowing the orientation of your plane is a real challenge,
even for experienced pilots. You just have to work at it and some adults have
a real problem with left and right regardless of which way the plane is going.
Licensed pilots have a lot of trouble with this one as they are accustomed to
being in the plane.
Here are two suggestions on how to work on orientation when you are not
Use a flight simulator on your PC. Pick a slow flying model and fly it a lot.
Forget the jets and fast planes. Pick a slow one. Focus on left and right
coming at you. Keep the plane in front of you. Don't let it fly over your
FMS is a free flight simulator. It is not the best flight sim, but the price
is right and it works. There are also other free and commercial simulators.
FMS Flight simulator Home Page
Parkflyers for FMS
The links below take you to sites that provide cables that work with FMS. If
your radio has a trainer port, these cables allow you to use the trainer port
on your radio to "fly" the
simulator. This is an excellent training approach.
An alternative is to try an RC car that has proportional steering. You don't
have to worry about lift, stall and wind. Get something with left and right
steering and speed control. Set up an easy course that goes toward and away
from you with lots of turns. Do it very slowly at first until you can make
the turns easily. Then build speed over time. You'll get it! If it has
sticks rather than a steering wheel even better, but not required. Oh, and
little cars are fun too.
3) Too much speed - Speed it the enemy of the new pilot but if you fly too
slowly the wings can't generate enough lift, so there is a compromise here.
The key message is that you don't have to fly at full throttle all the time.
Most small electrics fly very nicely at 2/3 throttle and some do quite well at
1/2. That is a much better training speed than full power. Launch at full
power and climb to a good height, say 100 feet as a minimum, so you have time
to recover from a mistake. At 100 feet, about double the height of the trees
where I live, go to half throttle and see how the plane handles. If it holds
altitude on a straight line, this is a good speed. Now work on slow and easy
turns, work on left and right, flying toward you and maintaining altitude.
Add a little throttle if the plane can't hold altitude.
4) Not enough altitude - New flyers are often afraid of altitude. They feel
safer close to the ground. Nothing could be more wrong.
Altitude is your friend. Altitude is your safety margin. It gives you a
chance to fix a mistake. If you are flying low and you make a mistake ....
As stated above I consider 100 feet, about double tree height where I live, as
a good flying height and I usually fly much higher than this. I advise my new
flyers that fifty feet, is minimum flying height. Below that you better be
lining up for landing.
5) Over control - Most of the time the plane does not need input from you.
Once you get to height, a properly trimmed plane flying in calm air will
maintain its height and direction with no help from you. In fact anything you
do will interfere with the plane.
When teaching new pilots I often do a demo flight of their plane. I get the
plane to 100 feet, then bring the throttle back to a nice cursing speed. I
get it going straight, with plenty of space in front of it, then take my hand
off the sticks and hold the radio out to the left with my arms spread wide to
emphasize that I am doing nothing. I let the plane go wherever it wants to
go, as long as it is holding altitude, staying upwind and has enough room. If
you are flying a high wing trainer and you can't do this, your plane is out of
Even in a mild breeze with some gusts, once you reach flying height, you
should be able to take your hand off the stick. Oh the plane will move around
and the breeze might push it into a turn, but it should continue to fly with
no help from you.
Along this same line of thinking, don't hold your turns for more than a couple
of seconds after the plane starts to turn. Understand that the plane turns by
banking or tilting its wings. If you hold a turn too long you will force the
plane to deepen this bank and it will eventually lose lift and go into a
spiral dive and crash. Give your inputs slowly and gently and watch the
plane. Start your turn then let off then turn some more and let off. Start
your turns long before you need to and you won't need to make sharp turns.
I just watch these guys hold the turn, hold the turn, hold the turn, crash.
Of course they are flying in 10 mph wind, near the ground, coming toward
themselves at full throttle.
6) Preflight check - Before every flight it is the pilot's responsibility to
confirm that the plane, the controls and the conditions are correct and
acceptable for flight.
Plane - Batteries at proper power
Surfaces properly aligned
No damage or breakage on the plane
Radio - Frequency control has been met before you turn on the radio
A full range check before the first flight of the day
All trims and switches in the proper position for this plane
Battery condition is good
Antenna fully extended
For computer radios - proper model is displayed
All surfaces move in the proper direction
Conditions - No one on the field or in any way at risk from your fight
You are launching into the wind
Wind strength is acceptable ( see wind above )
Sunglasses and a hat to protect your eyes
All other area conditions are acceptable.
Then and only then can you consider yourself, your plane, radio and the
conditions right for flight. Based on your plane, your radio and local
conditions you may need to add or change something here, but this is the bare
minimum. It only takes a couple of minutes at the beginning of the flying
day and only a few seconds to perform before each flight.
If this all seems like too much to remember, do what professional pilots do,
take along a preflight check list. Before every flight they go down
the check list, perform the tests, in sequence, and confirm that all is right.
If you want your flying experience to be a positive one, you should do the
same. After a short time, it all becomes automatic and just a natural part of
a fun and rewarding day.
I hope some of this is useful in learning to fly your plane.
10-19-2005, 09:44 PM
your stuff is great. Everyone should have it printed out and in a folder at home.
I would like to chime in though and say that ive flown- about 40 DIFFERENT planes, from small 20 inch spans witght through to larger 80 inch models (slimers), multiple wings, deltas, etc....and not counting the dozens of other planes either for test flights for others or just their planes themselves, plus helis, toys, ufos and so forth and ....
this parkzone plane (well the particular one that we have), has to be the hardest of all.....mainly due to that written above.
the articles you have would help anyone in flying, but unfortunately this little plane is what id consider a real motivation sapper for the budding enthusiast.
i had another plane like this once, and it flew, well once. Didnt crash it, but it had so many vices i never flew it again.
one thing though, and i havent seen it yet, is that apparently the PZ Decathlon flies great in no wind, and behaves well, as long as your instructios are followed (i.e. AoA, speed, tipstall etc).
ive only flown it in wind from moderate to probably too much, and it's more than a handful.
My 2c worth.
10-19-2005, 10:48 PM
I am glad you like what I post. I am just tyring to help the newer guys. I don't geat paid for this, other than a kind note like yours, now and then.
With the exception of the Parkzone Stryker and the HobbyZone Aerobird Xtreme, I don't consider any of their planes to be strong wind planes.
Be that as it may, in the hands of a good pilot the can be flown in 10 mph+ wind.
However, in my humble opinon no new pilot, flying a light weight plane, whether glow or electic, should be trying to train in anything but calm conditions.
Today I fly my Aerobird in 15 mph winds, just because I can, but it is a challenge. The Xtreme does much better in 15 mph winds, but it weighs 2 1/2 times as much and has a much higher wing loading and more powerful motor.
The Decathlon may simply be more difficult and more wind sensative than most.
So my advice to the new pilot is, put it away and start on an Aerobird, a T-hawk or an Easy Star. Much better suited to the new pilot. Come back to the D later. :)
10-19-2005, 11:02 PM
yeah i agree.
i had one of those aerobirds once and it was great.
the context i am posting in here is more trying to maintain/salvage the pilot's perception/enthusiasm for flying, as it seems that he might be thinking that all planes fly like this.
its one of those planes i have come across that really i dont like flying...
again though, it could be just this one, very possibly the wind (ive never flown it in calm conditions).
i flew it enough though to see that nasty tipstall on many occasions, which makes it a real ''sweater''.
PS kind notes coming your way mate, i wasnt aware of your articles until recently....a MUST for everyone.
10-20-2005, 02:38 AM
ive got alot of experience with this plane, as my bro in law just bought it to ''get started''.
for a trainer plane its got to be one of the hardest planes ive ever flown.
nasty tip stall, slow roll and reaction from rudder, almost uncontrollable in any kind of wind.
One more thing about both that Decathlon and the Cub: they are extremely HEAVY! :(
10-20-2005, 12:06 PM
Cheers for the advice/suggestions/comments etc.
I have read that information about the 6 point so flying before Ed, you posted it somewhere else... maybe rcuniverse.com. Good advice, have taken note, thank you.
I'm not disillusioned about flying, i already know that not all planes fly like this. I had a 2 channel glider for a while and that flew well... if a little too boring. Maybe gliders are something I'll grow into ;)
WIND: I haven't been trying to fly in anything other than dead calm...
Orientation: I've had radio controlled cars for years and years (have a 1/8 3.5cc rally car at the mo) and so have the left/right thing pinned.
Speed: It flys well flat out, which is still much slower than either my car or my .61 speedboat, so i'll stick with that for a bit then start reducing the throttle...
Altitude: Less is more? rubbish! it climbs now so theres no problem getting height... have stuck to the 100ft/35ish metre height...
Over Control: Now it flies properly this is less of a problem, the over control on my first outing was a consequence of it not getting up enough speed to actually fly... more "falling with style" (Buzz Lightyear, Toy Story). I have no problem with light use of controls either thankfully, my speedboat is set up to do a 90 degree turn whilst flat out (which throws it out of the water somewhat) just in case the worst happens and I don't notice a rock/duck/swan/other boat/swimmer until it's very late. (no i don't use it near life of any sort, human or not)
Preflight Check: Thats easy and only takes a sec...
Well, will go ahead and add that washout and report back.
I have both a mustang and a stryker as well... since the general concensus on this forum is that the decathlon is far harder to fly than it "should" be, how much messing about with the decathlon should i do before throwing the mustang up? The general concensus on the net that i have seen is that the mustang is a hoot to fly...
On the plus side, spares for the decathlon are signifcantly cheaper... £12 instead of £20 for a fuselage for example...
10-20-2005, 12:53 PM
Of the three the stryker will be the most fun and easiest to fly. Also the most crash worthy.
PZ Mustang looks good in the air, but reports are that is seriously underpowered.
When you are ready, look at some of the kits from Mountain Models, www.montainmodels.com (http://www.montainmodels.com) . These are so well designed and so perfectly cut you practically put a tube of glue in the box and shake. They all fly well.
if you want some Zip in your flying, try a Zagi TAZZ
75 mph in level flight and almost indestructable. With your experience with speed boats and cars, this should be right up your alley. These little RTF electics are going to be too limiting for you, except maybe the F27 Stryker. Put the combat module on that and find someone else to shoot down. :)
As for gliders ( my favoriate ) if you want some excitement, try slope soaring and then dynamic soaring! ( the dark side of gliders! :o) If you get into DS, your boat will seem tame!
How Slope Soaring Works
Videos of slope soaring - hope you have high speed line
Over the Rainbow
Dynamic Slope Soaring - definately NOT for beginners
Extreme Speed slope soaring
This is the real speed rush type of flying.
Motors? We don't need no stinking motors!!! :D
10-20-2005, 01:34 PM
AEAJR - thanks for the reply... Ok, maybe i'll take the stryker with me next time as well. I've heard the mustang isn't very powerful out of the box, i was planning to upgrade it before i even attempted to fly it. Upgrade the stryker as well? I know about the $35 upgrade thats a different prop and a 10 cell battery pack BTW, unfortunately i'll have to find a cheap supply of battery packs here (UK) to make it that cheap.
The reason i got bored with and sold my glider is the same as why slope soaring isn't going to be something i'll be getting into anytime soon... I live in Cambridge in England. East Anglia (the region of the country within which Cambridge is located) is like the Kansas of Britain. Flat, flat, flat :( which means lots of areas to go flying something powered... but no chance of an elevated position and no chance of a slope soarer being anything more than an ornament.
Hopefully I won't get too bored with these little electric planes... I don't have huge amounts of money to invest in this angle of the hobby at the moment :(
Ok, will probably post two crash reports next time then ;)
10-20-2005, 01:37 PM
Try the Stryker stock. Fun plane!
As for gliders on flat land, that is what I do most. Thermal soaring. I just love it, but I am not a speed junkie. I enjoy the hunt for lift.
Now, I have to ask a dumb and hopfully not an offensive question, as no offense is intended.
Why would a knowledgable RC guy like you buy these little prepackaged RTF electrics? They are intended for people who know nothing. You are very knowledgable. If it was to just buy and fly stock, I would understand. They are quick and convenient.
However you seem to be buying them with the intention of modifying them, which is completely contrary to how they are made and marketed. Why would you not have purchased ARFs and put in the right stuff? in the end that would be cheaper and you would have better equipment.
Using US$, between the D, the Stryker and the Mustang, you have about $550 for RTF stuff there, much of which you sound like you plan to abandon.
For example, if you change motors you are likely to burn up the stock speed controls, so you have to swap out all the electronics to move them over to "standard" radio gear".
If you bump the Stryker up to a 10 cell pack, you are likely to burn out the ESC, unless someone has already told you that it can take a 10 cell pack.
For $550 I can buy a nice computer radio with micro electroncis, a second flight pack and 2 planes with motors, and batteries and have it my way.
Or, you could get that computer radio with micro electroncis, an ARF Tiger moth 400 and put that up. Then spend $275 and pick up a Zagi Tazz and burn up the skies.
I hope you accept my questions as just curiosity. You are not the first person I have seen do this but you are probably one of the most experienced. I just wondered why.
I ask respectfully but with great interest.
I think these RTFs are fine, but I would never buy one with the intetion of immediately modifying it. I would get an ARF or a Kit and build that the way I want it.
10-20-2005, 01:47 PM
OK, will do so... thank you :)
08-31-2006, 09:59 AM
Anyone have any ideas why the flying characteristics are so different between these two planes? similar or alike in so many ways. near same wing area, same tail moment, same power. Decath slightly heavier. what I read about the cub is generally good, whereas the decath is depicted as a touchy time bomb. I have 2 cubs & a decath. Still crashing first cub, other two still in boxes. From what I can gather I just need to upgrade the power in all three. I am a lousy flyer, & will continue to punish the first cub & some pod & booms that I have before getting into the new planes.
08-31-2006, 10:52 AM
Welcome swamp! The wing area can make a difference as can CG locatio. You're doing the right thing by getting a lot of use out of the one plane before opening those other two boxes!
08-31-2006, 04:29 PM
I, too, have both the J3 and the Decathlon. I have been flying both of them for a year now, so I'll try to explain the differences as best as I can. While both planes use exactly the same motor, gear box, servos, etc., and their overall appearance is similar, the Decathlon is about 8% heavier and has a wing that is about 5% smaller. While these differences appear to be insignificant, the actual wing loading changes enough to make the two planes fly considerably differently. In their stock, directly out of the box shape, the Cub takes off decently (not counting the ground circles) and flies well at 50% throttle. I would typically get flights in excess of 10 minutes per battery. The Decathlon will take off at the same speed as the Cub, but because of its higher wing loading will be very close to its stall speed. As soon as the Decathlon clears the ground, you need to level it and let it build some more speed before climbing and making turns. At 50% throttle, the Decathlon flies on the verge of stalling. You need to increase the throttle to about 66% to get it to fly decently. This extra speed uses up the battery charge faster, so I would get about 9 minute flights with it. While the Cub is great to fly in still conditions, it is not good at handling any significant wind. The Decathlon, due to its greater wing loading, while not great, handles the wind considerably better than the Cub. The Dacthlon has larger control surfaces, which makes it perform loops, rolls and inverted flying better than the Cub.
I made the same modifications to the two planes: expandable foam in the nose section; PZ high pitch prop; Venom motor; tail wheel; taped antenna. After the modifications the Cub is still a better "gentle" flyer, but the Decathlon can be flown in greater wind and is more fun to fly inverted. Initially, I used to fly the Cub a lot more than the Decathlon (I actually bought the Decathlon on e-bay as a back-up in case I destroyed the Cub), but as I got better at flying, I found myself flying the Decathlon more and more, to where I now don't fly the Cub nearly as often as the Decathlon.
08-31-2006, 05:10 PM
I, too, have both the J3 and the Decathlon. I have been flying both of them for a year now, so I'll try to explain the differences as best as I can.
What a brilliant analysis and description of the differences of the two planes. We all owe you a big thank you!
08-31-2006, 05:51 PM
09-01-2006, 10:25 PM
thanks guys. think I'll add the venom & the expandable foam. Also have the new super cub waiting if I live long enough. LOL