TommyWatson

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Does anyone have a World Models UNIJET EP ducted fan model. How does it fly? any comments?

Regards

gosk8ing

hey,

I flew one about 2 weeks ago and didnt like it. Box says high power to weight ratio. Acceleration is slow. To taxi, it needed 50%-60% power to even move. On a smooth surface and at full power, takes about 30 metres to take-off; and thats with a bit of wind. Once in the air, it will fly around on 50% power, but slowly. The nose wheel is very weak, and broke it on second flight. I've only had two flights and dont want to fly it again (dont want to risk my battery). Even once trimmed, it has a mind of its own.

By the way, Im not that much into electric, so it might've been my setup. I ran a castle creations 40 amp esc, evo 3s 1800mAh 25c and hs-55 servos

Instructions great.
Construction look great except for the nose gear and CA hinges.
Hardware great.
Supplied brushless looks and runs well.

I might've just had bad luck, see what other people say.

figueroa

My Feedback: (22)

There are two at my club and they fly great.
As mater of fact I was at the local hobby shop today and picked one up.
We fly off a 50 X 500 foot plastic covered runway and they take off in about 50 feet.
They go together quickly and look great.

TommyWatson

My Feedback: (1)

One good report and one bad report. I will just have to see how mine goes. It is on its way.

Regards

phildo

Hey Tom,

How did the Unijet go mate...????

Any reports so far? Videos??

Phil

TommyWatson

My Feedback: (1)

It has not arrived yet. I will let you know how it flies.

Regards

CesarC

Hi my friend,

Can you help me with a question on my Unjet... I just bought one.... and I can't find the way to put in place the elevator pushroad,
please help me with this as it is not shown in the instruction manual

Regards...
Cesar

CesarC

Hi Figueroa,

I have a problem with the elevator push road of my best friend brand new Unijet, he cant find the way to place the elevator pushroad and he is new to jets, can you please help us, I have him on the phone and he is been trying to get a response from me but as I see on the instructions manual of the world models website, they dont explain how to place the push road... pleas this friend of mine needs your HELP !!!!!

Cesar
Mexico

TommyWatson

My Feedback: (1)

Hi Cesar,

You just need to push the elevator pushrod into the uppermost plastic tube. Push in the threaded end. It will exit the top of the rudder. Connect the clevis on the elevator end and the "Z" bend to the servo arm.. I glued my elevator onto the fin before I did this. I tried to be careful not to get an glue in the tube, but some did get in. I had to clean the glue out of the tube before the pushrod would come out.

bdavison

My Feedback: (1)

I bought one....
Its a testy son of a %&*&$%.

Tip stall like crazy if you get too wild on the elevator.
Needs quite a bit of runway to get it airborne, and just as much to land it.

That being said...its pretty sweet.
The stock motor is impressive. Its a good fan unit.

As far as flying....it will roll and loop and even stall turn. Flys im guessing in the 60-70mph range with a good downwind push. Although it wont do much, it is fun to fly...It will test your skills for sure. You got to be smooth with it. dont yank it around...it wont tolerate hard pulls. Go easy on the rudder.

Whatever you do...DONT SLOW IT DOWN on a landing. Keep some airspeed on it. If you get it too slow. It will drop a wing with NO warning whatsoever. I already had to rebuild on wing after it tipstalled on me on a landing approach and cartwheeled from about 4ft up.

The elevator linkage is a bit tricky. You will probably have to use a xacto to carve a little bit out of the top of the vertical stab where the linkage comes out so that the clevis wont bind up.

Your gonna need a 40A esc or above and a 3cell lipo capable of at least 20C to get any performance out of it.

Here is a pic of mine.

phildo

Good write up there BD.[sm=thumbup.gif]

Tom,

When did you pick up your UJ from? Order O/s or from Australia?

Phil

TommyWatson

My Feedback: (1)

Hi Phil,

I got it from Airborne Models. They advertise here on RCU. The shipping cost was US$42, So there may be cheaper places to get it. Have a look at Aircraft-World.


Regards

TommyWatson

My Feedback: (1)

Hi Phil,

Singapore Hobbies have them. Should be cheaper to send to Australia

Regards

bdavison

My Feedback: (1)

Some more tips.
Skip the rubber bands and ziptie the wings together. See the pic above for an idea of what Im talking about. The rubber bands arent sufficient.

The nose wheel seems really weak when you first see it....but it works pretty good. Ive flown mine off rough grass runways, and it worked fine. I even drove it over a plastic coke bottle at full throttle on a take off run, and it still works fine.

There is no way in the world you can rip the main gear out...its solid as a rock. Watch the landings though. It has a tendancy to bounce...if it does bounce...even once...its gonna be a rough landing. If it bounces, hammer the throttle and go around for another try. Dont try to bring it in nose high harrier style...it wont do it. Keep it ripping pretty fast on landing approaches, and set it down smoooooooooth.
The manufacturers recommended throws are fine, along with the CG location. When you first check the CG its going to seem all wrong....its not.
Dont yank it off the deck in takeoff either. Let that puppy build up some airspeed before you rotate. If you snatch it off the deck...it will tip stall.

Ill just warn you now...the fan is freakin LOUD!!!! I mean you need earplugs loud especially when its at full throttle on a takeoff run. EVERYbody at the field will know when you are flying. It screams.
Mine was pulling 30A at full throttle, and the wattmeter showed 300W. AUW with battery was 16oz.

Like I said...its a touchy little thing, but it is fun to fly, and it gets alot of attention.

phildo

Thanks again for info BD .... LOUD HUH! Any videos with sound??

Always find it funny when people say electrics are quite! Foamie park flyer maybe ... Pump up the watts and its gets a bit noisey. Personally, I dont mind a little noise .. as long as it doesnt upset the the locals nearby (who wants to hear a EDF at 5:30 am on a Sunday!!). I mostly fly at the club anyway.

Also, Thanks Tom for the info on SH. I've just seen one yesterday at the LHS. Might support him a bit and buy from him. Its good to have the choice though.

TommyWatson

My Feedback: (1)

G'Day Mate,

I am just waiting for a larger sped controller and I will have mine ready to fly. I will do a video if I can.


Regards

phildo

Rodger that Tom,

Look forward to the vid. What size ESC did you have and what are you going to now mate? I read that it's pulling 30 amps and up ... so I was looking at a Ewatts 40 or a SJpro 40. Thoughts ???

TommyWatson

My Feedback: (1)

Well I have a 20a esc so I ordered a 30a, but after reading the comments above, I think I should have gone for a 40a. I will keep you informed. The servo plates for the aileron servos are a bit flimsy but I guess they will be OK.

I have a hyperion helios 63 arf and the quality is so much better. Some arfs are OK but htis one is very ordinary.

Regards

bdavison

My Feedback: (1)

Ill try to get some video soon. As far as the sound....everyone so far that has been close to it at full throttle has plugged their ears. Its insanely loud.
If you put it on "slow start" and let it spool up....it sounds JUST like a turbine.
After I got it built I spooled up the fan in my living room at about 2am.....There were lights coming on at my neighbors house. NO JOKE.
Gotta be the loudest EDF ever.

When you put those little plastic servo mounts onto the servo covers...be sure to use epoxy...dont just ca them on there.

phildo

Ha! ... Thats funny!

I bet your neighbours wonder whats going on next door!

I'll pick one up in the next few days .... Working 10 days straight .. again

Phil

phildo

Tom,

What are some of your thougths as to why this plane is a bit ordinary??

Is it just the build or value for money or what ???? Rubbish accessories ????

Would like yours or anyone else's two cents worth ....

I have been looking at the MP twister also .... but thats another thread

Phil

bdavison

My Feedback: (1)

I think he means ordinary in the sense that the plane is very simple. There's nothing really "out there" design wise.
Its a very clean ARF, no frills. Just a simple EDF.

I have to say even with all its quirks, it is fun to fly. Challenging, but fun.

Im not a big jet person...most of my planes are aerobatic prop planes. But I like to get my hands into all types of flying. I was brousing through the hobby shop and saw this thing. I was thinking about building a EDF, so I picked it up just to goof off with. It was low cost, and had the motor and fan with it...so.....

First flight, was off a grass field. I ran it up and let it go...and the grass was dragging it down so much it took about 50yds before it finally lifted off...and I yanked it off the ground....it dropped a wing, and I barely flew out of it.....did one circuit, and landed it.
Second flight, same grass field. I ran it over a plastic coke bottle on accident....which actually helped because it launched it into the air, and I was able to fly it from that point. I had a 25A esc in it...which of course got aweful hot pulling 30A through it. The ESC started cutting out...and I landed it after about one circuit.
Third flight - same grass field,...I ran it over the same plastic bottle on purpose this time, since it worked so well last time, and the jet was flying pretty well. Flew about 2-3 circuits this time, till the ESC started overheating again...and landed it.
Fourth flight - grass runway - changed the 25A ESC to a 40A esc, and decided to try it again. Took off after a long rollout. Flew around 2-3 circuits, and came back for a landing. I got it two slow, and it tipstalled from about 4ft up and cartwheeled down the runway. I spent the next two days rebuilding the right wing as it busted 3 ribs and the trailing edge, and the spar tube.
Fifth flight - took it to a mat runway. Plane took off nice and smooth with a good climbout. Flew around for quite sometime. Kinda feeling out the plane to see what I could do with it. Did a roll, loop, stall turn, etc. Came around for a landing, and watched the thing bounce about 4 times before I got it down....almost broke it up again.
Sixth flight - same mat runway. Same decent flight. Finding out that elevator is tricky...too much too fast, and it will stall quickly...even at high speeds. Gotta fly it smoooooothly. Landing again was Bounce Bounce Bounce...hmmm gotta work on those landings.
Seventh flight - mat runway - Same decent flight...started getting a little more brave with it this time. Low altitude full throttle fly-bys, etc. Starting to get used to its flight charectoristics. Finally got a half decent landing out of it this time. Still bounced, but not as chaotic as the last two.

I apparently am not a jet pilot...LOL

CesarC

Thank you very much Tommy for your help, I did not answer before... cause this is a jet of one of my friends, and he found the tubbing
just after I placed the last message you answered.... I want to thank you also for uploading the pics... for I know it takes time, we will try this Unijet next week but I have a lot of doubts about it..... I told him to use a 40 ESC, not sure if he got a 40 or 30 ESC, but with a 30 I guess he is going to be in the limit, I know from experience... I have 2 HET Super Snipers one with a 60 ESC and the other with a 77 ESC, the wattmetter reads 40-45 amps in static.. and I have a JEPE F-16.... almost ready, it hasnt flown yet.

This friend of mine told me that the motor is an outrunner inside a can, does the motor comes this way???? cause we usually use inrunners for jets and more in a 70mm or so diameter fan, if the motor is an outrunner it will not draw as much amps as an inrunner does ..............conditions being equal in both, (meaning both fans being the same ) and voltage being the same.... but if the motor the Unijet comes with is an inrunner, my friend is going to need at least a 50 ESC for sure.... and by the way.... we didnt mention we are in Mexico City at 7000FT from sea level... in essence the altitude would not harm the performace of the electric motor.... but the air the blades are moving is different at different altitudes, another thing that makes me doubt more is that, theres was a guy in my flying club that placed a landing gear on a Super Sniper...... the jet that weighted 800 grams..... did not take off..... he had to use a bungee as I do. I hope we will not end using the bungee. I have my doubts about this plane but I might be wrong. Have fun.

Thanks Tommy,

Cesar

TommyWatson

My Feedback: (1)

I have just finished a Hyperion Helios 63. The quality of construction, covering and accessories is much better than the Unijet. That is what I mean by ordinary. No better or no worse than most other ARFs, It is just not as outstanding as the Hyperion.

bdavison

My Feedback: (1)

Yes, the motor is an outrunner motor that is supplied with the unijet.

The bell of the motor is inserted into the fan blade hub, and bolted to the fan blade hub. The other end of the outrunner is bolted to the fan shroud housing. The shaft is not connected to anything.

Its actually a pretty slick setup, and its near impossible to mess it up or install it crooked.

As I said in a previous post....the motor will draw 30A at full throttle on a 3cell lipo. So Id highly recommend a good 40A ESC...preferably one with a heatsink.

Tommy, I know whatcha mean about the Helios...that thing is 100% TOP quality arf. It just doesnt get any better. Im having a blast with mine.