Go Back  RCU Forums > RC Airplanes > RC Jets
Reload this Page >

Skygate/CARF Viperjet

Notices
RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

Skygate/CARF Viperjet

Old 01-30-2020, 11:33 PM
  #601  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

Yes to everything. ER40
Old 01-31-2020, 06:13 AM
  #602  
tucson
My Feedback: (1)
 
Join Date: Dec 2001
Location: tucson, AZ
Posts: 865
Received 1 Like on 1 Post
Default

Originally Posted by Dave Wilshere
Yes to everything. ER40
hi dave,
as always thank you for your quick reply.
stan
Old 02-18-2020, 10:00 AM
  #603  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

Another Viper for a friend of Andrew’s...he was so impressed by the test flight he ordered one!





Old 07-11-2020, 09:23 PM
  #604  
Asif
My Feedback: (30)
 
Join Date: Oct 2004
Location: Edmonton, AB, CANADA
Posts: 306
Received 5 Likes on 4 Posts
Default

Test flew my Viper, what an amazing flying airplane. I have Jetcat P180NX for power which is ample!! I have my flap setup as Dave Wilshire's recommendation, no trim changes. CG is just being the main carbon wing tube, aircraft flairs great on landings.
The following users liked this post:
DenisFerrari (12-27-2021)
Old 07-11-2020, 11:03 PM
  #605  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

Asif

Glad it all went well...my favourite scheme 🙂

The kit I showed has also been flying, plus another Viper I test flew a couple of weeks back in Black/silver/orange scheme.

Dave



Old 07-12-2020, 08:37 AM
  #606  
USAF FLYBOY
My Feedback: (2)
 
Join Date: Sep 2004
Location: Cool Ridge, WV
Posts: 28
Received 0 Likes on 0 Posts
Default

Good to see that this thread is still alive. I used this forum for all the info needed to achieve a successful maiden after a recent month worth of building.

I had a Swiwinn 140b needing an airframe and I wanted a jet that could be built achieving a light wing loading due to the fact that our club here in WV has a less than 400' grass strip. Not to mention a hillside with trees at one end. I was concerned at first that I was taking a chance with the smaller turbine knowing what everyone else here is putting in theirs but one user on this thread was powering theirs with a 140N turbine and it gave me the courage to take on the project. The thing is (at our field) a go around is not an option unless a commitment to landing is cancelled and full power acquired before reaching the beginning of the strip. The only way I'm confident enough to try this is with airspeed telemetry reporting airspeed every second into headphones as I'm flying. First flight: determine stall speed right after takeoff so as to have as much fuel in tank as possible for heaviest weight. After that, stay above and all should be well.

Here are some of the specs:
Less than 32 lbs dry and using only 2.8L tank.
CG: approx. 1/2 in. behind rear of wing tube with only UAT full. (With the batteries above front wheel, 8 oz. of lead above batts. used to achieve this.) Btw 0 trim needed on maiden.
Full flaps: 85 deg.
Elevator: 30mm up and down with 40% expo. Approx. 1/8 in. down elevator with full flaps.
All other surfaces are as the manual suggests. NO dual rates are used on my setup for controller simplicity.
Top speed reached so far is 142 mph and out of a dive I could get faster.
Stall speed is somewhere in the neighborhood of 37 mph.
Stall characteristics are great if straight and level but if abrupt full elevator is applied near stall speed then it will tip stall as you would expect.
I will say it's a nice performing model. Nothing exceptional with 140N, but fun to fly.
Decals for Mclaren scheme were purchased at Taylormadedecals.com as recommended by this thread.

Overall I love it. Burned about 8 gals. in it so far. Can't wait to fly again!

Thank you all for sharing your experiences and knowledge!



Old 07-12-2020, 08:42 AM
  #607  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

I bet you are nose heavy and can take the lead out. All of ours have the batteries around the fuel tank. The huge tail masks the nose heavy set up- even super nose heavy no elevator trim is seen.
How does it balance without the wings?
Old 07-26-2020, 07:56 AM
  #608  
USAF FLYBOY
My Feedback: (2)
 
Join Date: Sep 2004
Location: Cool Ridge, WV
Posts: 28
Received 0 Likes on 0 Posts
Default

Old 07-26-2020, 08:06 AM
  #609  
Asif
My Feedback: (30)
 
Join Date: Oct 2004
Location: Edmonton, AB, CANADA
Posts: 306
Received 5 Likes on 4 Posts
Default

I’ve got 8 flights so far on my viper, simply love it. I agree with Dave, too I feel my viper is nose heavy. Currently it’s balanced at the center of the wing tube. I’ve pulled aircraft 45 degree nose high, roll inverted and the nose does drop both upwind and down wind.
Old 07-26-2020, 09:05 AM
  #610  
USAF FLYBOY
My Feedback: (2)
 
Join Date: Sep 2004
Location: Cool Ridge, WV
Posts: 28
Received 0 Likes on 0 Posts
Default

I told you all wrong when I said I had mine balanced at .5 in. behind rear of tube. I double checked and I'm 1.5 inches behind rear of tube with UAT full and it flies inverted with little to no pitch change.
Old 08-19-2020, 05:23 PM
  #611  
tucson
My Feedback: (1)
 
Join Date: Dec 2001
Location: tucson, AZ
Posts: 865
Received 1 Like on 1 Post
Default Carf viper

I just finished upgrading my 3 year old carf viper to a set of electron electric gear.I have used the nose gear door prior to the upgrade. my question is how many of you have used or left the gear door off. I had to trim the opening so will have to make a new door to fit properly.
Do you really need one?
Stan
Old 08-19-2020, 09:05 PM
  #612  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

Stan

In the UK it’s about 50/50 with and without and to be honest I can’t notice a difference. Balance is the most important update you can make 🙂

Dave
The following users liked this post:
DenisFerrari (12-29-2021)
Old 08-19-2020, 09:43 PM
  #613  
tucson
My Feedback: (1)
 
Join Date: Dec 2001
Location: tucson, AZ
Posts: 865
Received 1 Like on 1 Post
Default nose gear door

dave,
awfully large gaping hole where the nose wheel sits.
feels funny to look at it.
after you came out with your description to balance from the wing bolts mounting holes I tried it and removed a pound and a half of lead from the nose.plane flew great with no cg problems.
thanks
stan
The following users liked this post:
DenisFerrari (12-29-2021)
Old 08-20-2020, 02:10 AM
  #614  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

You get used to the hole! I like doors as we fly on grass throughout the year, but other than that it’s another failure point

Good to hear like everyone you like the balance
The following users liked this post:
DenisFerrari (12-29-2021)
Old 08-20-2020, 03:41 AM
  #615  
RCFlyerDan
My Feedback: (54)
 
RCFlyerDan's Avatar
 
Join Date: Apr 2002
Location: SWFL
Posts: 2,004
Received 68 Likes on 51 Posts
Default

I’ve had mine since 2012, and started off with a door. It was torn up after running off the runway into rough grass. I took it off several years ago and haven’t missed the aggravation. It isn’t a scale jet, and you don’t see the hole going by at 150+mph.
Old 08-22-2020, 01:46 AM
  #616  
LewisE1
 
Join Date: Aug 2010
Location: Berkshire, UNITED KINGDOM
Posts: 106
Likes: 0
Received 6 Likes on 6 Posts
Default

could someone please post a photo of there main gear if using electrons ? there looks like just enough material on the bearers to get screws in without modifying on my new kit
The following users liked this post:
DenisFerrari (12-29-2021)
Old 08-22-2020, 04:39 AM
  #617  
tucson
My Feedback: (1)
 
Join Date: Dec 2001
Location: tucson, AZ
Posts: 865
Received 1 Like on 1 Post
Default

Originally Posted by LewisE1
could someone please post a photo of there main gear if using electrons ? there looks like just enough material on the bearers to get screws in without modifying on my new kit
I cannot post a picture right now but yes I had to add a 1/8 strip of hardwood to narrow the bearer. I used hysol then I glued a 3/32 piece of light ply to the bottom of the bearer which helped support the hardwood strip.In my case I also had to fill the previous mounting holes with hysol. My kit is 3 years old and wasn't set up for electrons.
I would have thought that Carf would have adjusted the bearers now that they are selling Electrons. I used blind nuts which were to wide so I removed one of the flanges on all 4 blind nuts to fit.
Stan
Old 08-22-2020, 06:59 AM
  #618  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

We add a strip 6mm deep and 2mm wide to each side and then put a 1mm glass plate over the whole lot.

The kit has not updated yet because of the number of people still with Air retracts. Soon I guess.

The following users liked this post:
DenisFerrari (12-29-2021)
Old 08-22-2020, 06:36 PM
  #619  
USAF FLYBOY
My Feedback: (2)
 
Join Date: Sep 2004
Location: Cool Ridge, WV
Posts: 28
Received 0 Likes on 0 Posts
Default

I used a piece of aluminum made to fit between the retract mount and wood attaching points and just gave the retract a larger footprint. This did, however, relocate the retract so that it protrudes out past the wing skin and keeps the gear covers from sitting flush.
Old 08-23-2020, 06:08 AM
  #620  
RCFlyerDan
My Feedback: (54)
 
RCFlyerDan's Avatar
 
Join Date: Apr 2002
Location: SWFL
Posts: 2,004
Received 68 Likes on 51 Posts
Default

Originally Posted by Dave Wilshere

The kit has not updated yet because of the number of people still with Air retracts. Soon I guess.
I’ve modified, which didn’t take much, my Viper and CARF Lightning with Air Behotec C50 retracts. My old Flash had C36 air retracts. IMHO.....I consider them to be the best air retracts on the market. I’ve heard good things about their electric retracts. I was glad when CARF didn’t use Airtech anymore. I liked his spoked wheels and his struts were good, but the retracts, especially the nose gear retract wouldn’t take much abuse when running off the runway into the rough.
Old 08-23-2020, 11:31 AM
  #621  
Dave Wilshere
 
Join Date: Jun 2002
Location: Watford, UNITED KINGDOM
Posts: 13,084
Received 731 Likes on 527 Posts
Default

Behotec C-36 and C-50 are the daddy of air retracts. My original Classic Flash is 14 years old and the gear and valve are perfect still.
The following users liked this post:
DenisFerrari (12-29-2021)
Old 11-20-2020, 09:56 AM
  #622  
Haisan
 
Join Date: Apr 2005
Location: LahorePunjab, PAKISTAN
Posts: 8
Received 0 Likes on 0 Posts
Default

Originally Posted by Asif
Test flew my Viper, what an amazing flying airplane. I have Jetcat P180NX for power which is ample!! I have my flap setup as Dave Wilshire's recommendation, no trim changes. CG is just being the main carbon wing tube, aircraft flairs great on landings.
Hi Brother,
What are flaps recommendations? Throws? And CG for maiden?
Old 11-20-2020, 10:48 AM
  #623  
Asif
My Feedback: (30)
 
Join Date: Oct 2004
Location: Edmonton, AB, CANADA
Posts: 306
Received 5 Likes on 4 Posts
Default

Originally Posted by Haisan
Hi Brother,
What are flaps recommendations? Throws? And CG for maiden?
Hi Sunny,
My controls surfaces are as follows.
Elevator for takeoff and landing +/- 35mm
Elevator during flight +/- 20mm
Aileron +13mm / -20mm
Rudder max throw you can get.
Take off flap 20 degrees (elevator down by 0.5mm measured at elevator root.)
Landing flap 85 degrees (elevator down by 2.5mm measured at elevator root.)

The CG is AFT of the wing tube. During test flight and subsequent flights, the CG was at the centre of the wing tube. The aircraft felt heavy especially during loops and required considerable elevator. Same was the case during landing, bit heavy and it was hard to flair the aircraft. After moving the CG just behind the wings tube, the aircraft feels light and flairs nicely on landings. I believe the CG can go further back but it is as per my flying style, I am happy with it.

Regards
Asif


Regards
Asif
The following 2 users liked this post by Asif:
Agrav8ed (11-20-2020), Haisan (11-25-2020)
Old 11-25-2020, 07:00 PM
  #624  
Haisan
 
Join Date: Apr 2005
Location: LahorePunjab, PAKISTAN
Posts: 8
Received 0 Likes on 0 Posts
Default

Thank you my friend. That's a great help. Kit is here and I am building it now. Any pictures for equipment plates? Have you installed smoke? I am thinking to not to and build it lighter.
Rgrds,
Old 11-25-2020, 07:02 PM
  #625  
Haisan
 
Join Date: Apr 2005
Location: LahorePunjab, PAKISTAN
Posts: 8
Received 0 Likes on 0 Posts
Default

Hi,
Anyone using cortex gyro? Would love to have some tips for gain settings (assistance mode)

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.