Espritmodel.com Telemetry Radio
Reply
Thread Tools
Old Jan 04, 2009, 06:45 AM
Launchpad McQuack
Prop-er's Avatar
Netherlands, Moordrecht
Joined Sep 2004
1,130 Posts
Hi!

I think the 40" Rafale needs a motor with 75-100 gram weight and around 1000 kV. Best prop would be an APC-E 9x9 which should pull about 25A on a 3S lipo.

http://www.r2hobbies.com/proddetail.php?prod=rcps81518
http://www.hobbycity.com/hobbycity/s...Simple_30A_ESC
http://www.r2hobbies.com/proddetail.php?prod=pba1517011
http://www.aircraft-world.com/shopexd.asp?id=3700

In my case (20" Rafale) the (light) battery is placed at the front, underneath the canopy. I think in your case, with the relatively light motor and heavy lipo, the lipo can be placed more aft. Which is nice, because the length of the motor/battery wires could be causing problems.

I think the center of gravity is 830mm from the nose on the 40" version.

Program: www.drivecalc.de
Prop-er is offline Find More Posts by Prop-er
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 04, 2009, 08:46 AM
Registered User
Sartor's Avatar
Brasil
Joined Jun 2008
46 Posts
nice project, thanks a lot for the plans
Sartor is offline Find More Posts by Sartor
Reply With Quote
Old Jan 04, 2009, 11:24 AM
Registered User
Joined Dec 2008
6 Posts
Prop-er, thanks a lot for all this information, well I think i will buy a more powerfull motor; for the ESC and the battery, no problem, I allready have it...

I will inform you and send some Fotos when finished !
quigonjinn37 is offline Find More Posts by quigonjinn37
Reply With Quote
Old Jan 07, 2009, 02:29 AM
Registered User
Rolla, MO
Joined Jan 2009
3 Posts
I am extremely interested in the software used in designing this plane! Can you tell me what you used??!!
DFisher777 is offline Find More Posts by DFisher777
Reply With Quote
Old Jan 19, 2009, 10:59 AM
The VF4 Lightning III Project
Muzzy_II's Avatar
Scotland
Joined Jan 2009
210 Posts
Hi there,
I was hoping you could give some examples of electrical equipment that would suit the 20" version. Motor, servo's etc
Great plans and looks to be a good plan also.

Thanks
Muzzy_II is offline Find More Posts by Muzzy_II
Reply With Quote
Old Jan 19, 2009, 01:59 PM
Launchpad McQuack
Prop-er's Avatar
Netherlands, Moordrecht
Joined Sep 2004
1,130 Posts
A 25 gram 1600kV brushless on a APC-e 6x5,5, running on a 3S 20C lipo of about 500 mAh, a 10A ESC on a four channel lightweight receiver and two 5gr servo's is all you need. Shouldn't cost you much more than 50 bucks if you shop in China.
Prop-er is offline Find More Posts by Prop-er
Reply With Quote
Old Feb 14, 2009, 07:04 AM
Registered User
LI, NY
Joined May 2006
229 Posts
Hey Prop-er,

Thanks for the great plans. I am building the 40" version. Am I missing something or, is the wing section bigger than a sheet of FFF and it needs to be made in 2 parts? I was thinking of slicing it at mid-chord and gluing it together with a full-width CF tube spar. What do you think? I would think that 40" wings with no spar would be quite floppy, no?


Thanks again,
Adam
raceradam is offline Find More Posts by raceradam
Reply With Quote
Old Feb 14, 2009, 07:20 AM
Registered User
pval3's Avatar
raleigh, NC usa
Joined Aug 2001
1,948 Posts
sheets n spars

Hey there adam

I have this plane on the "back burner" right now but have run into this problem in the past with other designs...esp with the depron stuff!

Cut and butt two pieces of FF together to make the proper sized sheet..make sure you get a nice square edge to ensure a nice glue line and use wax paper to keep it from sticking to your building surface when you are gluing!

I like to use a tool I picked up at Michaels crafts for cutting picture matting with a straight edge to guide the process.

I have found that the span needs a nice spar, I like the 5mm light weight tubes run tip to tip as close to the forward tip of the wing tip as possible...

be careful though . . . cg can be effected if you are not careful before you cut and glue.

I had a mirage 2000 a few years ago that I had to switch to a 1/8 tube with 2 flat .5 mm X 4 mm placed vertical 4" in front of and on the trailing edge to make it resist flexing.

I think that I could have done away with the mid spar .5mm flat spar if I had left the film on the ff... hind sight is 20/20!
pval3 is offline Find More Posts by pval3
Reply With Quote
Old Feb 16, 2009, 04:40 AM
To Build? or Build Another?
genetix's Avatar
Los Angeles, CA
Joined Feb 2009
145 Posts
Thanks fo those planss from me too! I have been looking for big jet foamie for a while and most of my fleet include delta wings so this plane is nearly perfect. Im going to build the 40" XL version. Whats that you ask? Print it tiled on letter paper, insert tiled papers to the copy machine at work and enlarge to tabloid (11x17) to make a ??" Version of Proper's Rafale. I think it will be some where around the 50-60" wing span.

I just got a brand new 2700 kv motor that is supposed to run 100" mph on a 5x5 apc prop, along with 3s2p 4400 25c batteries so this is the power system... I think i need a better amp though, my cheap hobbycity 40amp gets wayyyyy too hot to keep that current!

Well, this postpones the big project... again... (97" Hercules from elmers foam board)
genetix is offline Find More Posts by genetix
Reply With Quote
Old Feb 16, 2009, 09:09 AM
Malaysian Flier
Selangor, Malaysia
Joined Jan 2008
237 Posts
Hello.. I'm trying to build 20' but don't know what the cg.. please..

thank...
zhnme523 is offline Find More Posts by zhnme523
Reply With Quote
Old Feb 16, 2009, 10:01 AM
Launchpad McQuack
Prop-er's Avatar
Netherlands, Moordrecht
Joined Sep 2004
1,130 Posts
20' ??? They seem to get bigger and bigger...

http://www.rcgroups.com/forums/showp...1&postcount=34
Prop-er is offline Find More Posts by Prop-er
Reply With Quote
Old Feb 16, 2009, 10:09 AM
Launchpad McQuack
Prop-er's Avatar
Netherlands, Moordrecht
Joined Sep 2004
1,130 Posts
Quote:
Originally Posted by raceradam
Hey Prop-er,

Thanks for the great plans. I am building the 40" version. Am I missing something or, is the wing section bigger than a sheet of FFF and it needs to be made in 2 parts? I was thinking of slicing it at mid-chord and gluing it together with a full-width CF tube spar. What do you think? I would think that 40" wings with no spar would be quite floppy, no?
Hi Adam,

The 40" would definitely require some stiffening of the wings. I guess a 4mm CF tube would be a good start. I've found that the nose is quite brittle, and must be reinforced to withstand nose-down landings. A pair of CF rods along the fuse (from nose to about halfway the fuse) should be enough to keep this machine in one piece on one of your bad flying days.

Ahh, if I only had time to finish the repairs on my little Rafale...
(I know, it's a priority thing)
Prop-er is offline Find More Posts by Prop-er
Reply With Quote
Old Feb 16, 2009, 06:36 PM
To Build? or Build Another?
genetix's Avatar
Los Angeles, CA
Joined Feb 2009
145 Posts
I have so many parts and power systems from over time in this hobby and i feel so bad not using them. they cost a lot of money. SO micheals had a sale and foamboards were $1! I got 20 of them and now I have plans for 4 planes including this one (yes, I spent a lot of money "learning" this hobby...) but Im so excited I think i might dump the current one and start this... BIG FOAM JET.. FINALLY!! Thanks Proper!

Question: Has anyone tried or has a theory about KF Airfoils for this plane? Proper have you tried / had any success on an airfoil? Thanks!
genetix is offline Find More Posts by genetix
Reply With Quote
Old Feb 17, 2009, 01:14 AM
Launchpad McQuack
Prop-er's Avatar
Netherlands, Moordrecht
Joined Sep 2004
1,130 Posts
Well, if you build according to plan, the wing will have a really nicely shaped airfoil. During the short time I flew mine, I noticed good flying manners. (come to think about it, I never really flew something that had bad manners)(well, apart from the Hydrofoam, then)

The small one will normally have a higher wing loading than the big one. Still I was able to slow down to walking speed, and accelerate to 80 km/u in no time, without trimming. It all felt pretty straightforward, no bad habits. Stalls come nice, straight an easy. Stall telltales are very pronounced.
Prop-er is offline Find More Posts by Prop-er
Reply With Quote
Old Feb 19, 2009, 10:16 PM
To Build? or Build Another?
genetix's Avatar
Los Angeles, CA
Joined Feb 2009
145 Posts
thanks for the info, I hadnt noticed in the plans that there is an airfoil... come to think of it, I havent seen a build log for this plane at all... Maybe my project will be worth posting

Colors decided (for now...): white fuse, blue wings, blue tipped tail and silver/gray nose. what do u think?

Im wondering if I might take on adjusting for some thrust vectoring... Hmm....

Thanks for the info proper!
genetix is offline Find More Posts by genetix
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Dassault Rafale RSteel Pusher Prop Jet Models 43 Dec 23, 2010 11:37 PM
Burt Rutan's Pond Racer, Shockflyer Style IAD Foamies (Kits) 36 Mar 24, 2009 06:52 PM
60" ShockFlyer style Katana with Hacker A30-16M Turbo442 3D Flying 8 Nov 09, 2005 09:25 AM
Convair CV440 shockflyer style hb9jnh Foamies (Kits) 1 Apr 30, 2005 11:19 AM
Cessna Citation Shockflyer Style hb9jnh Foamies (Kits) 9 Apr 08, 2005 10:57 AM