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-   -   C-ARF Ultra Flash build Thread + Video (https://www.rcuniverse.com/forum/rc-jets-120/10016814-c-arf-ultra-flash-build-thread-video.html)

Dave Wilshere 08-24-2011 06:05 AM

RE: C-ARF Ultra Flash build Thread + Video
 
Goose

I wasn't sure when I got it, as I only wanted the blue swapping to red, not the green lower check. But now I have flown it, it shows up well.
Model was built to sell anyway, so as long as the new owner likes it then great!
Hopefully we will post a short video of the performance on the P-80 model soon..whole point in building it really!

Dave

gooseF22 08-24-2011 06:18 AM

RE: C-ARF Ultra Flash build Thread + Video
 
I would like to see someone put one of the smaller lighter motors in one and see where everything ends up and how it performs with the 90/100 class smallblocks..

gooseF22 08-24-2011 06:20 AM

RE: C-ARF Ultra Flash build Thread + Video
 
dup

Dave Wilshere 08-24-2011 09:51 AM

RE: C-ARF Ultra Flash build Thread + Video
 
We have someone doing a P-100 powered version when they are here..

Dave

gooseF22 08-24-2011 10:16 AM

RE: C-ARF Ultra Flash build Thread + Video
 


ORIGINAL: Dave Wilshere

We have someone doing a P-100 powered version when they are here..

Dave
waiting.........:D

ddlstang 08-24-2011 12:09 PM

RE: C-ARF Ultra Flash build Thread + Video
 
I know someone that had a rabbit in a CF and it flew great. Actually was a lot easier to fly than the bigger engines. Would take off of 400' with ease and had good verticle and would still hit the speed limit.

wojtek 09-14-2011 07:45 AM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)
After a busy summer with a lot of interruptions, my Ultra Flash is finally ready for flight. I hope to take the jet up in the air this Saturday [8D] .. I hope to have some video up on my youtube page soon of the UF

http://www.youtube.com/wiwanczyk



inspiration/idea :D :D

http://www.youtube.com/watch?v=4TshFWSsrn8

http://www.monsterworldrallyteam.com/




~V~

jzuniga 09-14-2011 07:51 AM

RE: C-ARF Ultra Flash build Thread + Video
 
Holy @%&* Wojtek! That looks bad to the bone!... Is the underside a light color? I mean for good SA out in the sun or overcast days?

Z

wojtek 09-14-2011 07:55 AM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)


ORIGINAL: jzuniga

Holy @%&* Wojtek! That looks bad to the bone!... Is the underside a light color? I mean for good SA out in the sun or overcast days?

Z

thanks :D[8D]


here's how the bottom looks ....



~V~

jzuniga 09-14-2011 07:55 AM

RE: C-ARF Ultra Flash build Thread + Video
 
Cool vids btw! especially like the part where the guys' on the sedgeway and the cars doing circles around him!;-)

Z

jzuniga 09-14-2011 07:57 AM

RE: C-ARF Ultra Flash build Thread + Video
 


ORIGINAL: wojtek



ORIGINAL: jzuniga

Holy @%&* Wojtek! That looks bad to the bone!... Is the underside a light color? I mean for good SA out in the sun or overcast days?

Z

thanks :D[8D]


here's how the bottom looks ....



~V~
SWEET!

Z

Colin Allen 09-23-2011 10:43 PM

RE: C-ARF Ultra Flash build Thread + Video
 
Well after waiting three months for my engine to turn up (a JetCentral Cheetah) I can now finish my UF. Almost done, should be maidening it sometime in the next week or two when I can escape the work travel!

Cheers,
Colin

AFTERBURNER1 09-24-2011 02:28 AM

RE: C-ARF Ultra Flash build Thread + Video
 
Straight up Riverside California paint job..[8D]

Colin Allen 09-27-2011 08:50 PM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)
<style type="text/css"><span style="font-family: Arial;"><! Font Definitions */@font-face {font-family:"*S 明朝"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:128; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:fixed; mso-font-signature:1 134676480 16 0 131072 0;}@font-face {font-family:"*S 明朝"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:128; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:fixed; mso-font-signature:1 134676480 16 0 131072 0;}@font-face {font-family:Cambria; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 0 0 0 1 0;} Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"*S 明朝"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"*S 明朝"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:EN-US;}@page WordSection1 {size:595.0pt 842.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;}div.WordSection1 {page:WordSection1;}></span></style><p class="MsoNormal"><span style="font-size: small;"><span style="font-family: Arial;"><span lang="EN-US">Is anyone else worried about the fact that the Flash (both versions) has no airflow through the fuse and over the outside of the thrust tube? I know there are hundreds of flashs flying successfully without worrying about this, but I have also heard of two crash and burns resulting from the canopy flying off, quite likely due to pressure build up. Aside from that potentially fatal issue, having the outer tube contacting the fibreglass exhaust nozzle would (I would imagine) over time cause heat discoloration/deformation. Anybody have any such experiences? The NACAintakes are not going to help much as there is nowhere for the air to go as the end of the fuse is totally sealed around the outer tube.

I am particularly concerned about this as I have put smoke in mine so am not using the inlet joiner.

From what I can tell the Flash is the only CARF jet designed this way - all the others (from what I can tell - I haven't checked in detail) allow air to exit around the outer tube.

Anyway, better safe than sorry, so with advice from a very experienced friend, I cut some half moon cutouts in the back end of the fibreglass fuse (and matching cutouts in the exhaust nozzle), and cut the exhaust nozzle shorter to allow air to flow through the fuze and out around the outside of the tube. It also ensures the exhaust nozzle is not in direct contact with the outer thrust tube. I actually like the look of the thrust tube extending beyond the exhaust nozzle anyway :)

Anyway, my UF is pretty much done - just a few finishing touches, CoG and apply my decals and I'm good to go :)

Cheers,
Colin</span></span></span></p>

KC36330 09-27-2011 09:21 PM

RE: C-ARF Ultra Flash build Thread + Video
 

ORIGINAL: mincherallen

............I have also heard of two crash and burns resulting from the canopy flying off, quite likely due to pressure build up...............

I've heard of one, and he clearly didn't hit the hole with locking pin when installing the canopy, it slid under the canopy and it wasn't holding it on, it was evident in a pic taken just before the incident........

http://images.rcuniverse.com/forum/u...81/Ig11049.jpg

as for cooling, the inner pipe is shorter then the outer, and the gap between them causes a venturi effect with the jet blast and it draws air between the pipes. the NACA inlets allow cool air to be drawn into the area where the outer pipe can draw that cool air in.

paulhat 09-27-2011 09:42 PM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)
Hey Guys,

Just wondering if you had installed the U shaped main leg covers that are supplied with the kit.
The ones I have are clearly the wrong height and will therefore not push deep enough into the wing without me hacking a heap off the bottom of the moulding.
[img]Moulding.jpg[/img]
Do you think there would be any disadvantage in not installing them and also leaving the doors off?

I was thinking that leaving them off may cause extra pressure to build up inside the wing possibly causing failure?

Anyway my build is almost done apart from the wing. This is the only part of the kit I would have a complaint about. Too much grinding and trying to work things out for my liking :) Would be nice if CARF could make the leg moulding and extension of what is allready there.

Thanks for your help.


Paul.


KC36330 09-27-2011 09:47 PM

RE: C-ARF Ultra Flash build Thread + Video
 
flew my classic Flash without the mail leg doors and never had any issues

Colin Allen 09-27-2011 10:39 PM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)
Hey Paul... you just cut the bottom off and they fit fine. The air cylinder goes over the bit you've cut out anyway, so you cant really see it (I took this photo early in my build before finishing the wing for a friend building his at the same time who had the same question).

Cheers,
Colin

Dave Wilshere 09-27-2011 10:51 PM

RE: C-ARF Ultra Flash build Thread + Video
 
All three of my Flashes don't have the covers (pockets and leg) None have been a problem. The leg almost fills the void when the gear is up and my Flashes won't do 200 with the gear down;)

Dw

Colin Allen 09-28-2011 01:06 AM

RE: C-ARF Ultra Flash build Thread + Video
 


ORIGINAL: KC36330


ORIGINAL: mincherallen

............I have also heard of two crash and burns resulting from the canopy flying off, quite likely due to pressure build up...............

I've heard of one, and he clearly didn't hit the hole with locking pin when installing the canopy, it slid under the canopy and it wasn't holding it on, it was evident in a pic taken just before the incident........

as for cooling, the inner pipe is shorter then the outer, and the gap between them causes a venturi effect with the jet blast and it draws air between the pipes. the NACA inlets allow cool air to be drawn into the area where the outer pipe can draw that cool air in.
Great pic!! I assume it did not end well?

Thanks for the comments... good point re the venturi effect, and particulaly in flight at full noise none of what I've said would be much of an issue as the engine will suck every bit of air available anyway. The two "incidents" I referred to both happened after 6-7 minutes of flight, so the canopy was definitely properly attached. They occurred (in both cases) with low throttle on a high speed descent where it looked like the ram air effect resulted in pressure build up and the canopy clearly popped. I just felt better safe than sorry, and anything that gives better airflow through the plane has got to help. Of particular concern too is on the ground after flight and even after shutdown where a lot of residual heat is trapped particularly in the aft section below the tail. The NACAinlets are of no help when taxing or after shutdown as there is no airflow.

Great to get your thoughts and experience on this... thanks!


paulhat 09-28-2011 03:29 AM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)
Thanks for the advice on the leg moulldings and doors.
Think I will leave the mouldings off and put the doors on.

I was putting the canopy together the other day and thought I would try holding it together with magnets while it dries.
Using Formula 560 glue. All I do is put the glue on to one section at a time, put the magents on and then wipe the excess glue off.
Seems to work fine.

Paul.

sc0tt 09-28-2011 03:53 AM

RE: C-ARF Ultra Flash build Thread + Video
 
1 Attachment(s)


The magnet trick is great for canopies &amp;I normallyuse Hysol 9462. You must scuff up the inside of the frame and contact area on the canopy.I put small squares of plastic film (saran wrap) on the inside magnets so they do not get glued in. Any excess that comes outside is easily removed with alcohol. If done right, you will get a uniform solid bond.</p>

KC36330 09-28-2011 04:04 AM

RE: C-ARF Ultra Flash build Thread + Video
 

ORIGINAL: mincherallen

Great pic!! I assume it did not end well?
not at all the plane belonged to Pete (phjoker) and he has replaced it with a new flash and is still flying it i believe...........although checking the canopy before takeoff :)
http://images.rcuniverse.com/forum/u...81/Yt63191.jpg


sc0tt 09-28-2011 04:09 AM

RE: C-ARF Ultra Flash build Thread + Video
 
<span style="font-size: larger">

ORIGINAL: mincherallen
</span><style type="text/css"><span style="font-family: Arial;"><! Font Definitions */@font-face {font-family:"*S 明朝"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:128; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:fixed; mso-font-signature:1 134676480 16 0 131072 0;}@font-face {font-family:"*S 明朝"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:128; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:fixed; mso-font-signature:1 134676480 16 0 131072 0;}@font-face {font-family:Cambria; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 0 0 0 1 0;} Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"*S 明朝"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"*S 明朝"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:EN-US;}@page WordSection1 {size:595.0pt 842.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;}div.WordSection1 {page:WordSection1;}></span></style><p class="MsoNormal"></p><span style="font-size: larger"><p class="MsoNormal"><span style="font-family: Arial"><span lang="EN-US">From what I can tell the Flash is the only CARF jet designed this way - all the others (from what I can tell - I haven't checked in detail) allow air to exit around the outer tube.
</span></span>
</p></span><span style="font-size: smaller">
<span style="font-size: larger">The CARFLightning(old &amp;Ultra)and BVMUltra Bandit all use the NACA inlets.They work as designed with no issues.
http://bvmjets.com/Pages/Addendums/UB%20Addendums.htm

page 16 in Lightning manual
http://www.carf-models.com/public_ca...structions.pdf</span>
</span>

paulhat 09-28-2011 04:13 AM

RE: C-ARF Ultra Flash build Thread + Video
 
Hey scOtt,

You totally stole my idea there :)
Now I have to order more magnets so I can do mine all at once as well :)

Man that poor Flash [:o]

Paul.


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