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CARF Ultra Flash Evo build thread +

Old 05-17-2023, 06:59 PM
  #626  
camss69
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Originally Posted by essyou35
I did a quick maiden on my jet today, flew 3 minutes then landed. I flew a little over 1/2 throttle on my k130 and it moves along ok, looking forward to opening it up.

kinda odd, it felt nose heavy but the elevator is twitchy. I have it set to the correct throw and I only had about 35% exp, Ill add some more to 50%. Very odd for a jet, thats 3d plane level expo there!

However I wonder if my issue is because I am using 1.25" servo arms? They are the hangar 9 1.5" arms but I am on the 1.25" hole. Could that be why? Myabe move down to 1"?

I could only get 3.25" on the flaps so I’ll have to mess with the linkage to get more, but it still slows down nice with crow in it. No take off flaps. Maybe I’ll just keep it this way. I could come in no power.
Congrats!

Is it possible you have the expo backwards? I did a maiden on another guys plane and he had the expo backwards. Didn’t realize it, added more expo for the next flight and it was obviously worse! Then we figured it out.
Old 05-17-2023, 07:06 PM
  #627  
essyou35
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Originally Posted by camss69
Congrats!

Is it possible you have the expo backwards? I did a maiden on another guys plane and he had the expo backwards. Didn’t realize it, added more expo for the next flight and it was obviously worse! Then we figured it out.
Im using JETI now and I have a +50% now on the elevator, positive expo appears to be correct.

To achieve the throw needed, I only 33% range, and I added a bit more than the recommended throw on my high rates and that is 50%. Does that imply servo arms are too long?
Old 05-17-2023, 08:24 PM
  #628  
essyou35
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I went ahead and ordered some 1" arms that will allow me to use .75" as well.
I think it was mentioned before but with the CG set at 9.25" with a full UAT, the jet will sit on its but if I lift the nose. Of course the CG move forward with a full tank but I assume we already talked about this due to the rake of the gears?
Old 05-17-2023, 08:42 PM
  #629  
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UF elevator is designed to reach ideal movement at 20mm servo arm length, so 3/4” would be OK. 1” and 1 1/4” is too long.

elevator is powerful, 40-45% Expo is normal for non Gyro flyers. With gyro 35-40% would be normal.
Old 05-17-2023, 09:11 PM
  #630  
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Originally Posted by Dave Wilshere
UF elevator is designed to reach ideal movement at 20mm servo arm length, so 3/4” would be OK. 1” and 1 1/4” is too long.

elevator is powerful, 40-45% Expo is normal for non Gyro flyers. With gyro 35-40% would be normal.
Thats probably my issue then. Will have changed out by the weekend and will try again.

Im hoping the 130 is enough power. I could see myself upgrading!
Old 05-18-2023, 10:46 AM
  #631  
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I forgot to ask, is there a way to make the brakes stronger? Im using a 2s directly to the controller. They work but not super strong. With a 130 I can spool up to 50% without it moving forward, I could probably take off with the brakes on.
Old 05-18-2023, 03:12 PM
  #632  
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I don't think I have any brakes that will hold the airplane about 50% throttle. Sounds like they're already quite strong. Are you using electron or JP?
Old 05-18-2023, 05:12 PM
  #633  
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Originally Posted by FlyJ
I don't think I have any brakes that will hold the airplane about 50% throttle. Sounds like they're already quite strong. Are you using electron or JP?
I forgot there are elxtrons too. I have the JP retracts.

All my jets with air brakes hold the jet to at least 90%.

It doesnt need to hold the jet really, I was just using that as a reference. But they are not super strong. The wheels will not lock up.
Old 05-18-2023, 08:47 PM
  #634  
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What channel percentage? More than 100% will give more brake.
But holding a model jet on brakes and releasing makes the take off unstable. It’s also super dangerous as I have seen one brake release, the model turns towards the pits…if the other releases too the model is fired into the safety line.
Old 05-19-2023, 07:57 PM
  #635  
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Ok so I got some 1" servos arms, I had to use the 1" hole as I am using some beefy turnbuckles. I would have to widen the servo door slot for part of the eyelet to go into the cover a bit to use the 3/4" hole in order to get 1.5cm of travel.
After landing, I had a few mm of up elevator trimmed in, that must mean Im nose heavy still? Im really close to 9.25 but slightly forward. Or is some uptrim normal for this jet?
Definitely a weird flight, nose heavy with a touchy elevator!

If 1" isnt going to cut Ill have to go back to the stock pushrods. But Im wondering if 1.5cm is really needed as I flew with low rates at 1cm and never had to yank the stick all the much even being nose heavy.

Thoughts?


Old 05-19-2023, 08:53 PM
  #636  
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Flying with a small amount of up trim is normal on the Evo.
You need to adjust to your requirements, add expo or reduce movement till you feel aileron and elevator matches in feel, it is the on,y way you can fly smoothly

Do a pattern 45 degree up line and roll inverted to check balance 3 minutes into flight.

Dave
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Old 06-07-2023, 09:14 PM
  #637  
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Just about wrapping up my marathon of a build.

CG wise, I’m running the Jet Tech tank (4L) and put “Landing Fuel” in it, which I’m saying is 1L (1/4 tank) and I’m sitting at 234-235mm. Hopefully that’s going to work.



Old 06-08-2023, 09:56 AM
  #638  
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Will start nose heavy as you have more fuel than stock. But it will be perfectly controllable. You can then tune to suit your thumbs.
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Old 06-12-2023, 07:18 PM
  #639  
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Not sure about JP hobby stuff. Anyways not sure why CARF included the brake/retract combo controller. The brake controller on that is not AMA compliant IMO. It does not stop the jet. I have my rates up to 150% and it has 0 impact.
I put in a order for the stand alone brake controller that takes up to 6s and it can output up to 10V. The combo controller puts out about 6V.

If it still dont work well, Ill have to get the electron setup.

Today had my 3rd flight and a nasty tip stall on landing over the runway. My issues is trying to slow it down too much because the brakes are useless. Fortunately all I suffered is a dislocated tire and a wing tip scrape. I want to be able to land too fast and know I can count on the brakes, not have to land too slow because the brakes suck ass.
Old 06-12-2023, 08:48 PM
  #640  
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The JP brakes will lock solid! So something on your radio set up.
What altitude you at? Ultra Flash will touch down at walking pace, no wing drop. My normal ground roll is 150’ in light wind with little braking. In a breeze it will touch down walking pace!
Old 06-12-2023, 08:51 PM
  #641  
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Old 06-12-2023, 08:55 PM
  #642  
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I'm using jeti. The tires do not lock. Like a said 1/4 throttle on the 130 and it will move.
the stall was dead slow. I'm stiIl getting used to it.

Btw if in turns while banked sharo my nose is dropping a bit. Nirmal?

Lmk what is going on with my controller.


Old 06-12-2023, 08:58 PM
  #643  
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Don’t know this guy…but no wing drop here.
Old 06-13-2023, 10:42 AM
  #644  
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Not sure why you are butt hurt about the wing drop, there are other videos were it has it:
This is what happened to mind just only about 1 foot up:

Most jets drop a wing on stall so not sure what your issue is but its clear I wont get help here. Im questioning if you even have the jp retracts.
I sent an email to Mike maybe he can help and I hope the external brake controller from JP will help me out.
Old 06-13-2023, 11:15 AM
  #645  
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I’ve flown more UF than anyone alive…never had one drop a wing. There were 5 UF Evo’s flying at last weekends Jet meeting here…none dropped a wing.
My Evo has JP gear as supplied by CARF and as landing in my models maiden video just posted. The thread start shows my gear installed.
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Old 06-13-2023, 11:35 AM
  #646  
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I dont really care about the wing drop, I just want to be able to stop! SO apparently me, and the other guy in the video, amongst others, just suck at flying and can cause a wing to drop magically. Got it!

I really need to figure out why my brakes barely work so I cant just land faster and it will never be an issue again.
Old 06-13-2023, 02:58 PM
  #647  
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Question Ultra Flash EVO -- Air inlet dimensions / area

Hello, would any CARF Ultra Flash EVO owners be kind enough to provide dimensions, area, etc., of the air intakes? I am looking to potentially install a Schubeler EDF in the model, but the size of the motor will need to correspond to the air intakes. Despite my best efforts, I have been unsuccessful in gathering this information. Any guidance would be greatly appreciated!

Thank you,

Bret M.
Old 06-13-2023, 04:01 PM
  #648  
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Reach out to Christian and Schübeler Jets.
The joker is the better option and Schübeler makes inlet and exhaust

The red joker in this photo has a DS 98 installed
for the joker
Old 06-13-2023, 04:26 PM
  #649  
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Thanks so much for the quick reply. I have actually been in contact with Christian at Schubeler -- he is the one requesting the information that I'm seeking. I've also interfaced with Mike and Ray at CARF, but they haven't had much luck coming up with the information (at least so far). Christian has echoed your advice about the Joker, but I've always wanted a CARF Flash and I'm up to the challenge if it's possible to make it an EDF.
Old 06-13-2023, 05:22 PM
  #650  
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How do you want me to measure it? Is odd shaped.

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