View Full Version : RBC LA5.
01-06-2004, 07:42 PM
I'm a happy Oily. Look what awaited me when I got home yesterday. RBC's newest toy. A 1050 mm wingspan Lavochkin. I also recieved one of the new Typhoon outrunner motors.
01-06-2004, 07:51 PM
Lets have a look at whats inside. The wood parts are all CNC (computer controled router) cut. And theres a stack of 1.5mm sheeting balsa, also a bag of hardware bits, CAD drawn plans as well as thee vacume formed parts. I always have trouble shoting pics of the clear parts. So I threw a Typhoon 15 motor and a can in for referance.
01-06-2004, 07:55 PM
It's impresive to think that this motor flies this size plan better than the speed 600 and gear box it replaces. You can down load a vid of the LA in flight from this site. http://www.rbckits.com/id70.htm lets have a look at the comparison shot.
01-09-2004, 11:00 AM
Well I spent some time cutting out parts for the fuse and getting things figured out. For those of you who haven't built an RBC Kit (well ya there may be a few) the balsa parts are CNC cut. Computer controled router table. The parts are retained in the frames with a few small tabs. This methode of cutting leaves a slightly fuzzy edge. Wich I figure makes a better bond than die or laser cutting. But thats just an opinion.
01-09-2004, 11:03 AM
Not much time for modeling today. But managed to tack a few bits together.
01-09-2004, 11:06 AM
As you can see from the pic cooling air comes in by the spiner and through the scoop ontop of the cowl, flows over motor and batteries and exits from what would be exaust pipe exit area on the real plane.
01-10-2004, 12:47 AM
Managed to add a few more bits today.
01-10-2004, 07:39 AM
Looks like a nice kit ! Did you order direct from the Netherlands ? What cells will you be using ?
I flew over Powell River on my way back from Tokyo to Vancouver the other day !
01-10-2004, 10:06 AM
Do you ever go down town to the electronics district when your there?? I wounder what the battery prices are like?
The only down fall to these kits is the translation on the building notes is a bit rough. But they get better with each kit thay comes out. Usualy airflow for the batery pack is something the builder has to add in. On this LA model they already thought about that. I'm hoping to have this one done in a month or to ready for the first big fly weekends in the Vancouver area.
01-11-2004, 01:36 PM
Well had anouther go last night. Had to go over the liner pieces with a Razor planer. To fair things out a bit. As you can see in the next shot the crutch boards overlaped the side formers a little.
01-11-2004, 01:38 PM
Of course now is a good time to putin the push rod for the elevator.
01-11-2004, 01:41 PM
And now the sheetings mostly done. HHmm what next. I'm feeling guilty about not working on the Mars. Maybe I should do a little on that this weekend.
01-11-2004, 06:49 PM
And cut out and glued up the light ply cowl. Proped up the plastic bit of the cowl for looks.
01-12-2004, 10:54 PM
Needed the wing so that I could figure out the wing fairing. So lets get it done. The sheeting gets cut out and glued together first. Then the spar and rib assembly gets glued onto that. Here I've got the sheeting glued and alignment marks put down.
01-13-2004, 12:04 AM
The ribs all interlock with the spar.
01-21-2004, 01:15 AM
Well been too busy to do much building lately. But the wings sheeted and the servo pockets are pretty much done. Glued on the the tail surfaces. Though the rudder is supposed to be none functional. I couldn't resist.
01-25-2004, 07:14 PM
Well not much happening. Working to much lately. But heres where wer'e at.
01-25-2004, 07:17 PM
The tip blocks are quite long ruffed them out with razor planer last night. Hope to finish sand them after dinner.
01-25-2004, 07:24 PM
The fairings are .4mm ply on the bottom and 1mm balsa on top. There not pre cut but templates are given on planes. A generous amount of ply is given. once the top sheet is done some triming needs to be done.
01-25-2004, 07:26 PM
Top sheeting ruffed out on other side.
01-25-2004, 07:28 PM
Anouther view of the cooling air outlet. I need to add some more ply to here to simulate cowl flap.
02-02-2004, 02:03 AM
OK here's a look at the cowl flaps. And the intake from scope on top of cowl.
02-02-2004, 02:05 AM
Been busy at work this week. So not a lot of progress.
02-02-2004, 02:08 AM
THis shot looking though the cowl and to the side you can see air exit hole leading out to the cowl flap.
02-02-2004, 10:55 AM
Well added two large blocks of balsa to the bottom of wing. I had to bevel the top of the blocks a bit to match the contour of the wing. I think more was supposed to be whittled away. So as to be flush with tail section. But I left it a bit oversize. This is the contact point on landings. So thats why I left it a little oversize.
02-02-2004, 11:00 AM
Got the ailerons hinged (two small thin bits of plastic) And pushrods done.Just need to tape up hinges on ailerons and tape over servo.
02-02-2004, 11:01 AM
oops lets try that pic again.
02-11-2004, 11:06 PM
Managed to spray a little paint lately. Chose the easy route. Spray enamel from WM. Can't spray this stinky stuff around te house. So took it to the shop (work). Can usualy hit it with a little paint just before I head for home. Anyway two color coats done.
02-11-2004, 11:07 PM
And this shot with a little help of my lovely assistant.
02-11-2004, 11:10 PM
The colors arn't quite right. But I didn't have color chips to take in with me. Otherwise would have gone the latex route. Here is a pic of intended scheme.
02-12-2004, 11:52 AM
I'm not an electric fan but I can spot a well built plane and good craftsmanship. Nice going. Let us lknow how it fly's. :D
02-12-2004, 10:35 PM
I didn't outline the servo instilation to any great detail. So I thought I would show anouther pic or two.
Usualy with the other RBC kits the designer shows the servos glued to the inside of wing skin. But I like to keep the servos re&re-able. That way I can have many airframes without the expense of a whole lotta servos. So I made a little cradle in the servo pocket.
02-12-2004, 10:37 PM
Oh and BTW thanks for the compliment Dave. Muchly appriciated.
02-13-2004, 08:24 PM
Color scheme is starting to take shape.
02-13-2004, 08:24 PM
02-13-2004, 08:26 PM
02-16-2004, 01:45 PM
Well I had planned to fly this first on HET's new brushless outrunner the T15.
But a fellow out back east wanted my demo motor more than I, so I sold it. And as yet havn't re-ordered. I'm waiting till the HET brushless controler is ready.
But the plane is ready enough for some flight testing. So I had the speed 600 masterairscrew gearbox combo that used to be the standard power system for RBC planes. So I will do a little flight testing with that. It will make for some interesting comparisons. You sure pay a weight penalty for using the speed motor. Because the 600 is so heavy the plane balances without the battery tucked up into the cowling as is suggested with a brushless motor. Balances a little nose heavy in fact. So the batery is going back on the wing basicaly right over the CG.
02-16-2004, 01:48 PM
The battery is nice and low in this position. And the motor as well sits quite low in the plane. Should be very stable. I HOPE!. To keep the battery from moving around There is velcro under and over the pack. As well as some balsa.
02-16-2004, 01:51 PM
With this arrangement the battery can be moved back and forth a little for fine tunning the CG. Lets hope it won't move on it's own!!
03-23-2004, 08:43 PM
Well been awhile since I posted on this topic.
I've been waiting for parts.
I tried the LA on 10 x Cp1300 cells and the speed 600/gear box combo. But I found this to be to heavy. At least for my flying skills any way. And wasn't able to fly it. I bieleve the wieght was 1.45 kg.
So now I finaly have a Typhoon brushless motor to strap in. As well this mourning I got my pheonix 25 controlers in. Got them from MEC in Washington State. Nice people to deal with.
So I will strap in these parts then head down to the hardware store to wiegh it in it's new configuration.
I picked up anouther solderless power tube kit. This time without the cells. I have some loose 1300 cells to put in it. I plan to use 8 cells in this kit. So as to lighten the wing loading further. But 8 8cells might not be enough. Well see.
Heres what you get in kit form.
03-23-2004, 08:46 PM
The beauty of this type of pack is you can pull out the cells and test each one once in a while. I number mine to help shuffle them when I put things back together.
02-27-2005, 06:01 PM
Well looks like I let this thread die for a while.
A lot has happened since my last post. But with big gaps between.
I tried the T15/10 and Nicds. I almost got it going and tip stalled it. The plane hit the ground and exploded. But some patience and a bottle of CA and we pieced it all back together.
The plane sat around for a while because other projects cuaght my attention. I tried the same motor and smaller prop (9x6 APC) and 3S2P 1500 lipolies. Which droped the weight. Tried that around Nov. But couldn't quite get the plane to gain enough forward momentum before it hit the ground.
Today I tried a new location. My favorite whenever the tides are low enough. The reason it suites the LA5 is that theres a long sand bar with thick tall grass down one side of this bay I fly at. Today many things came together. I had a day off, a low tide and no rain. It took a few tries. But the long grass saved the plane till I got the trims roughed out and my launch technique down. Its a little tricky for me. 1kg plane with a highly tapered 1 meter wing. But I got it down and the plane flew twice. Quite well. I only did some counter clock wise circling today. The plane is fast and nimble (nice word for touchy)
Oh darn the boss has an errand that cant wait. BRB Grr.
02-27-2005, 07:06 PM
Anyways. I flew it for two hops. Just round in circles. Tried some zoom passes. but was having a vibration above 70% throttle. I have quite a few T15/10s. This one has always given me grief from day one. So will switch that out for anouther tonight. Well I will try anouther brand of controler first. Just to see if its a problem betwen the controler and motor. That happens with outrunners sometimes. Anyway because of the vibration I was launching at about 70% throttle and flying at 50-60%. 60% was enough not only to keep moving well above stall. I could slowly gain elevation! Very very shallow climb or else it could and did once slow down too much and tip stall. At a healthy altitude I had it slowed down pretty slow. It tended to fall off to one side or the other.
Landings supprised me. I was flying between a pond and a large creek. I was unsure if I could get it in over the grassy sand bar. But I nailed it twice. The second I over shot my preffered spot so throttled up and carried on a little farther till I thought now or never. And landed with a slight cartwheel. When I trooped all the way down there I found I had landed in between two logs. I figured I had pressed my luck enough for the day. Anyways I want to get the motor issue sorted out so I can rev it up a little more. 80% throttle on take off I figure would be just right.
02-27-2005, 10:47 PM
Well was just playing with the controler/ motor. Switching the motor didn't help. So tried changing the timing from medium to low advance. That seemed to move the vibration to a higher RPM level. So going to switch the CC25 for a Tsunami 30 and see if it gets better or worse. If that does not solve it then I'm pulling the T15 out and going to the T29/10 Then I'll be able to use this :twisted:
3x12x6.5 Carbon blades.
02-27-2005, 11:04 PM
I couldnt help but notice all of the beer cans in your photos, reminds me of my work area :D
02-27-2005, 11:18 PM
Ya I was try to use the beer cans as a guage of how long it takes to build an LA5 :-)
But I started to get some rude coments about it over at RCG so decided to clean up my work bench. Some people have no sense of humour.
ron van sommeren
02-28-2005, 07:35 AM
Here's your chance to brush up on your Dutch (don't worry, lots of piccies too ;)),
a new RBC kit in the making, the F7U Cutlass:
02-28-2005, 11:03 AM
If you want to see the Cutlass flying down load this.
Theres a brief moment at the biggining where the camera man loses sight of it. But then its all good from there.
Rob is sending me a CD with uncompressed video clips on it. So soon I can mail out copies to anyone who wants one.
Thanks for the link Ron. I'm going to go look around that forum.
02-28-2005, 08:18 PM
Well I installed the Tsunami 30 on the T15/10. And that took care of my vibration. I have a CC25 from just before the USB mod came out. So maybe the programing just aint quite right for the HET outrunner. I need to hook up the Tsunami to my PC next and try some extra tinkering. :-)
03-21-2005, 07:56 PM
Well I have been mixing and matching parts here today. As flying was not an option. Anyways what I ended up doing was putting a T29/14 in my LA5 with that big three blade Aeronught folding prop. See pic.
I had installed the prop on my .40 size Condor ARf. Only to find out that combined with the T29/10 and 3S3P 1500 Kokams it was over 30 amps draw. 35 amps I think it was. I'm using a 30 Amp controler. And having just fried an expensive controler recently I'm a little shy about pushing things too far now. Anyways, I put the prop (3x 12x6.5) on the T29/14 motor. And was going to try the 3S batteries. But the 3S3P was a little heavy. It put the plane @ 1300 grams AUW. I found the LA5 is already a heavy enough hand launcher at 900 grams. Of course once up to speed its light and responsive and powerfull. I was about to pull the T29 stuff out and put it all in the Condor. But remembered my new 4160 Mah 2S Apoggee packs.. Hmm why not give it a try I thought.
I have not done any tests on Typhoon motors with less than 3S packs since my first T6/20 motor. And not a lot of testing at that. So this new set up T29/14, 3x12x6.5 prop and 2S2P 4160mah pack turned the prop at 5000 RPM, 16 AMPs @ approx 8V. The thrust by the feel of things is simular to the T15/10, 9x6 two blade and 3S2P 1500's. I'll know better once I fly it. Even though I have increased the motor weight the AUW is still about 900 grams. In fact perhaps a tad less. Its a cheap scale...
If I put this motor prop set up back in the Condor I may need to go back to 3S packs. But, I do have blades at 8 and 9.5 pitches. I think I'll experiment more at 8.4 volts and steeper pitch first though. I can also go 2S4P wich should keep the voltage drop low.
On the LA5 though at 16 AMPS I can actualy drop down from 2S2P 4200 mah by splitting up the pack to 2S1P 2100 Mah. The battery it turns out sits on the CG with the bigger motor. So now I'm thinking I can get the weight down to 800 grams or less with a simular thrust. Or go up to 2S4P 8000 mah for a 1100 aprox AUW. And fly about for quite some time.
I never thought lower voltages would be interesting!
03-21-2005, 09:18 PM
So wich prop do you think will look better on the fly by?
03-22-2005, 07:37 PM
The lower voltage will fly better on the larger 3 blade, so that's the way to go. The bigger the prop disk the more scale like the appearance.
03-22-2005, 08:03 PM
That music in the Cutlass vid is a great match for the content. The clouds worked well as a backround to give the feel of speed, I can see why Howard Hughes demanded clouds as a backdrop for his Angels from Hell production.
04-06-2005, 12:32 AM
I got the LA5 out on Monday with its new power set up.
It flew just fine but it was so windy I only managed flying about in circles. I'll have to wait for a low wind day to say how this copares to a T15 on 3S on a small prop. I didn't really try speed passes. I did do a few circuits with the flaperons down. And some slow flying to try and learn the stall point better. But with the wind blowing at small craft warning levels it was all kinda pointless.
As a side note it was extra fun flying at the beach as this big grumpy Swan was pretty insistant that the beach was his and I wasn't welcome there. I managed to give him the slip and flew a little farther down the beach. :-))
Anouther funny one. I brought the plane in to land just in front of me in a patch of tall grass. I managed the aproach just nice till it was about 10' from me, and about 13' high. Then the darn plane started to drift left, towards my head! Got a real good look at the inside of cowl as I ducted. My landing deteriated after that. But it went in nose first into the soft squishy grass anyways. So no harm done.
04-06-2005, 03:50 PM
OILMAN IS A BUILDING MACHINE!!!!!!
looks awsome so far!
04-06-2005, 04:30 PM
Seriously I agree with Matteo EVERYONE STAND BACK AND LET HIM GO!
04-11-2005, 07:48 PM
Not sure if anyone really cares. But here is todays experiments.
T2912/14 and the 3x12x6.5 and 2S. Not much good in 20 - 30 knot head wind :-) Had to keep the nose down to go forward sometimes.
T2912/14 and 3S2P. 9x6 APC E. Not much better. T15/10 and the same is way better. Well have not tried the T15/10 in this kinda head wind....
T2912/14 and 3S2P 12 x 6 APC E :-)))))) Pretty good. 21 AMPS initial hot off the charger. Non folding prop sucks on landing :-( The plane zoomed though on this big prop. Regardless of the gusty winds.
Need to order in some more folding prop adapters and such from Aeronuaght. I did not try the 3x12x6.5 on 3S today. But with the 2912/10 I got 35 AMPS initial last time 3S3P I tried. I need to try the T2912/14 with 3S that will be interesting. One thing for sure. The T29 is much quieter than the T15 in this plane. Wich I like. The T15/10 and /13 have the 3.2 mm shaft. Pretty wimpy for big props. I really like the 5mm shaft of the T29. Much more solid for big props.
I did my first roll with an RBC kit (LA5) plane today. And survived. Like I said my piloting skills really suck. :-) The plane rolled nice and steady and effortless really. Its time to build anouther LA so I have one nice fresh not all beat up one.
04-11-2005, 10:50 PM
Well I just tried the 3x12"x6.6" Aeronuaght prop with 3S3P Kokam 1500s.
23 Amps. 265 whatts. This is do able I think. The 3S3P will bring the AUW to 1100 (2.4 lbs) grams I guess.
This thread is slowly degrading into T29 testing thread.
04-13-2005, 10:44 PM
It's not a bad thing to have real world results from new products posted like this. The T2918 versions could be next and maybe even that dual inline motor setup. The product line is fleshing out nicely from the T3/3 to the T29/dually as well as the "inrunners" . There's a Typhoon for awful lot of applications. Now if only the time to build planes around each one was a little easier to find...
04-13-2005, 11:32 PM
Speaking of the T2918s I'm working on bringing some of those in. Soon man soon. I don't think my LA5 needs a double rotor. 265 whatts man!!! (out of my T2912/14)
Don't know what to say about not having enough airframes. Although for anyone out there needing smaller planes. I have a lot of HET Arfs kickin about here. As for the larger planes I just have kits.
As for time to build them. I spend most of my time at work fantising about early retirment. Real early retirement. Like now!
But it always comes back to that money thing......
04-13-2005, 11:46 PM
Doing this would be fun though. Just to say I don' that.
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