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C-ARF Ultra Flash build Thread + Video

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C-ARF Ultra Flash build Thread + Video

Old 10-29-2014, 01:14 AM
  #4476  
hbutler
 
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Been looking at turbines for my UF. I was very close to getting a k140 which seems like a very safe choice. Started considering 100 class given the fact that the field I fly at is not the biggest and so doing a lot of 199mph passes probably not going to be the bulk of the flying. Watched some videos and the lighter setups do seem noticeably different in terms of the overall flight envelope. But I do like to do the 199 every now and then.

Digging a little deeper, I took a look at the b100f. 100 size can putting out 120n. Weight is the same as a k100, heavier than a p100rx lighter than 140s. Seems like a nice compromise.

There are a few other factor to consider for the selection, but does anyone have any experience with the b100f in a flash and can comment on performance? Doesn't seem like a popular combo, so there is risk there.
Old 10-29-2014, 01:19 AM
  #4477  
Dieselman1220
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Cant help you on the bf100, but why not the rabbit sp? 24 pounds if thrust and really light and compact.
Old 10-29-2014, 02:37 AM
  #4478  
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Thanks for the suggestion. Might be an option. If my numbers r right, there is .4lbs weight difference ( rabbit being lighter) and a 3 lb thrust difference(b100f being stronger). Based on those numbers, I would lean towards the b100. I would assume .4 lbs could be saved other places.

The other factors like service, fuel consumption... Etc could sway things in the direction of the rabbit. But looking for someone who has stick time with this combo(and hopefully some other combo as a reference) to comment on performance
Old 10-29-2014, 04:16 AM
  #4479  
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Hello,
I fly off a both a paved runway as well as a grass strip.
I fly my flash with a Cheetah, take offs are a breeze on either surface, and flight envelope is great, it's very fast and also quite slow.
I get more comments on its slow flight than how bloody fast it goes! So it does go slow if you fly it gently. Most of my flight is at half stick.
My buddy flies his on a Rabbit, still takes off fine on either surface, but you want to be sure to use the full length of the grass strip.
(runway behind you is useless)
During a flight at a busy club with surrounding obstacles you can't really spool up the Cheetah, but vertical is sweet.
with a Rabbit the plane seems to fly just quick, as long as the Cheetah can't really stretch it's legs to build its momentum up.
My buddy loves his with the Rabbit, it flies great, it does look very light in the air.
I do recall one situation where he wanted a Cheetah.
He was excited to fly and tried to takeoff without taxiing the full length of our strip, as he lacked speed he aborted, unfortunately he ran into the rough grass and his plane flopped onto its top, unfortunately it broke its nose!
During the walk back to the pits his only comment was, I WISH I HAD MY CHEETAH in it !!!!!!!!!!
Hope that helps a bit, I would lean towards too much power, in my opinion too much power is just enough!
Richard
Old 10-29-2014, 04:32 AM
  #4480  
Dave Wilshere
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We have a lot of UF flying with P-100Rx and P-90Rxi turbines, will try and get some video as performance is plenty, we fly locally just off a 300' grass strip and the UF's powered by the 100 and 90 all get out easily (using flap!-amazes me when I see people taking off without)

Dw
Old 10-29-2014, 06:18 AM
  #4481  
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Got an K140G in mine with saddle tanks and all ends up as an pretty heavy total.
But performance is excellent!! Rockets unlimited vertical

But i'm in the process of building an new/extra/spare one and that's will be with the K100G and i'm going to try to lose all the weight i can to get an as light as possible total weight.

That must make an difference in flying and especially landing…… (i hope )
Old 10-29-2014, 09:07 PM
  #4482  
raron455
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ANYONE have any pictures of how they transport their flash/Ultra flash,, I have an 18ft enclosed trailer, I set it on the bed, but want to actually make something to hold it secure, and not on the rear stabilizer/elevators... Not sure which way to go,,, any ideas would be appreciated fellas, pictures would be golden,, thanks
Old 10-30-2014, 05:28 AM
  #4483  
BoomerSooner
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I use 2" wide Velcro straps on a 3" piece of foam. Works perfectly. I just have the elevator control horns off the back of the foam.
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Last edited by BoomerSooner; 10-30-2014 at 05:32 AM.
Old 10-30-2014, 01:50 PM
  #4484  
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Originally Posted by spike5150
I just got the new JR Airspeed sensor. Any recommendations on where and how to mount the pitot tube on an Ultra Flash?
Anyone? Help appreciated!

Jeremy
Old 10-30-2014, 02:28 PM
  #4485  
Dave Wilshere
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Never done one, but wing is hollow, accessible through wing tank opening...
Old 10-30-2014, 03:37 PM
  #4486  
mitchilito
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Originally Posted by raron455
ANYONE have any pictures of how they transport their flash/Ultra flash,, I have an 18ft enclosed trailer, I set it on the bed, but want to actually make something to hold it secure, and not on the rear stabilizer/elevators... Not sure which way to go,,, any ideas would be appreciated fellas, pictures would be golden,, thanks
Made mine out of PVC pipe. Works for assembly/disassembly at the field.
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Old 10-31-2014, 08:12 AM
  #4487  
tellmic
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Mitchilito,

What are you going to do with that bottle whiskey? Needed before flying ,stress relief???
Old 10-31-2014, 04:55 PM
  #4488  
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Originally Posted by Dave Wilshere
Never done one, but wing is hollow, accessible through wing tank opening...
I guess wing is best spot - thank you.
Old 11-01-2014, 08:27 AM
  #4489  
Midas D.
 
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Getting organized

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Old 11-01-2014, 09:33 AM
  #4490  
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That looks really nice.

I have the same scheme. Second best would be that f20 scheme Phill Noel has done in my opinion.

Anyone know where I could get replacement "o rings" that hold the composite air trap tank? Mine gave out and I'm using rubber bands for now.
Old 11-01-2014, 10:25 AM
  #4491  
cbooth1979
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Looks good Midas, I flew mine a few weeks ago with a K-100g and it was plenty of power. Maybe its just my imagination but it did seem to land nicer as well. I think the 100's will still do 210-215mph if you hold it full stick for a lap or two. There was no problem taking off from grass as well.
Old 11-01-2014, 10:26 AM
  #4492  
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Originally Posted by andretorres89
That looks really nice.

I have the same scheme. Second best would be that f20 scheme Phill Noel has done in my opinion.

Anyone know where I could get replacement "o rings" that hold the composite air trap tank? Mine gave out and I'm using rubber bands for now.
I think Dreamworks sells them, check there site out.
Old 11-01-2014, 10:38 AM
  #4493  
andretorres89
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Originally Posted by cbooth1979
I think Dreamworks sells them, check there site out.
i have been on their site and they don't sell it separately.
Old 11-01-2014, 11:15 AM
  #4494  
Midas D.
 
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Originally Posted by cbooth1979
Looks good Midas, I flew mine a few weeks ago with a K-100g and it was plenty of power. Maybe its just my imagination but it did seem to land nicer as well. I think the 100's will still do 210-215mph if you hold it full stick for a lap or two. There was no problem taking off from grass as well.
That sounds like "music in my ears"
Old 11-01-2014, 11:21 AM
  #4495  
Dieselman1220
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Dreamworks does sell them..
http://www.dreamworksrc.com/catalog/...ds=Cat+o+ring+
Old 11-01-2014, 11:26 AM
  #4496  
andretorres89
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Originally Posted by Dieselman1220
Thank you dieselman! For some reason I couldn't find them.
Old 11-01-2014, 12:42 PM
  #4497  
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Hello all! Yesteday my Jet Cat 120 SX seized just after take off. I could land my UF safely and after inspection I found out that the turbine had substantial damage. That's why I am considering not repair it and purchase a new one. I was thinking in a Jets Munt Merlin 140. Has anyone an opinion on this combination of plane and turbine? Is there a lot of modifications to be made to the UF or is it just a simple fit? How well does it fly and if the residual thrust of the 140 would make landings more difficult. Any comments are welcome.
Old 11-01-2014, 12:48 PM
  #4498  
Dave Wilshere
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Takes 2-3 full power circuits to reach maximum speed with a 100 size turbine. The higher gas velocity really needs a slightly smaller tail pipe for maximum speed, but its still 220ish
Old 11-01-2014, 02:53 PM
  #4499  
DrV
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Originally Posted by jampl
Hello all! Yesteday my Jet Cat 120 SX seized just after take off. I could land my UF safely and after inspection I found out that the turbine had substantial damage. That's why I am considering not repair it and purchase a new one. I was thinking in a Jets Munt Merlin 140. Has anyone an opinion on this combination of plane and turbine? Is there a lot of modifications to be made to the UF or is it just a simple fit? How well does it fly and if the residual thrust of the 140 would make landings more difficult. Any comments are welcome.
i have the M140x in my UF and I love it. Don't quote me but I think it's slightly smaller then the 120 you have and lighter. You would not need much modification to install. I have no problems landing the plane. You can use more flaps like DW recommends or use crow like I do to land. I prefer crow. Buy it and you won't regret it.

Last edited by DrV; 11-01-2014 at 02:56 PM.
Old 11-02-2014, 01:53 AM
  #4500  
Midas D.
 
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Originally Posted by Dave Wilshere
Takes 2-3 full power circuits to reach maximum speed with a 100 size turbine. The higher gas velocity really needs a slightly smaller tail pipe for maximum speed, but its still 220ish
Hi Dave,

What do you suggest on diameter for an smaller tail pipe for the 100 size?

Thanks,

Ed

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