Posts: 434
Score: 142 Joined: 9/5/2009 Last Login: 5/9/2013 From: stirling, UNITED KINGDOM Status: offline
Thought I would post some info on this profile, mine is built and about ready for maiden so my info may be usefull for others who may like the look of this model.
First I will say im not a great pilot and a total 3d beginner, can hover badly but should really be concentrating on perfecting acrobatic flight than moving on to 3d, but what can I say, love power to weight, must come from my gsxr addiction.
I should also make clear that im in the uk, this means that my plane choices are limited, not so much by choice but cost, most of the aeroworks/greatplanes/hanger9 planes are availible in the uk (special order for some) but the cost by the time the tax man and post and middle man take their cut makes these models silly priced.
Anyway I ended up with a sbach 20cc profile, the same one from peak models/redwing. I really want a mojo 65 or balsastore sbach but due to cost and time went with the quick option and bought one of these to see me through the summer with the thought of building a true profile over the next winter.
Well to cut a long short I loved this model, it was super light compaired to any other 20cc petrol arf I had and had amazing power to weight, I watched a good 3d pilot wring its neck and could only dream of doing the same. BUT it was a bit heavy on the wing for a 3d learner like me in a harrier and had a fair bit wing rock that made it not ideal for a 3d beginner. But it was still the best flyer I had so I was looking for a long summer improving my skills with it.
Unfortunatly the forth time I had her at the field I lost her, I just had her cog perfected and the expo the way I felt comfy. I took off and she climbed, I tried to level out, she went vertical, I thought the wind has got under the wing so I went for the loop, she kept the same trajectory, I realised I had no elevator control, she hit the ground after a 50 foot loop at half throttle, gutted. One bad thing I will say about this model is if you crash her the way I did there is no rebuild, the way she is built makes her near impossible to repair after a hard crash.
The sbach was 7lbs 8oz dry with heavy servos and a 190 gram homemade a123 2300 mah battery with a 800 sq/in wing. The thread I started on her is here.
Well I was not planning on a mojo build just yet and really wanted someting similar to get me in the air quick and had already seen the new yak version that was to be availible soon, with a bigger wing and stronger engine mount I thought why not having been happy with the way the sbach flew.
I have now put the yak together and hoped to fly her tommorrow but the weather is looking poor, the auw is 7 pounds 10 oz with the same heavy battery but the yak has a bigger wing at 1029 sq/in so should fly even better. This plane is very near the same size as my 30cc 26% pilot yak and has a wider wing and fatter aerofoil, just abit shorter wingspan, it will make the pilot yak feel like a fat lump. Will update after maiden.
Posts: 1104
Score: 108 Joined: 3/18/2008 Last Login: 5/18/2013 From: Greenwood,
IN, USA Status: offline
It's time to build a real profile like a MoJo65 or a Sbach65 now that the gear is freed up. If that's a DLE-20 you have then these will be your best flyers at that size.
Posts: 434
Score: 142 Joined: 9/5/2009 Last Login: 5/9/2013 From: stirling, UNITED KINGDOM Status: offline
Took me forever to do that last post due to timeout errors and other problems. The picture with the wings show a 30cc pilot yak wing against the 20cc sbach wing, I did not mean to post it there but not sure at this time how to remove it.
Thumbskull you are not wrong, I have wanted a profile for 12 months now and have looked hard at the mojo. As my flying skills grow so does my desire for performance, I cant keep up!. Im sure that this time next year I will have a mojo 65 built and flying but needed something quick to fly for a taster this summer in the 20cc size. The yak profile I have now will fly great, that im sure of but I dont think she will take a bump well, she is quite brittle. If I was where I am now in flying skills 6 months ago I would have had a mojo ready for this summer not next. Already looking at the 30cc size profiles as I find the 26% yak a bit fat!
Posts: 434
Score: 142 Joined: 9/5/2009 Last Login: 5/9/2013 From: stirling, UNITED KINGDOM Status: offline
Well got a break with the weather and flew this profile YAK today. First flight was made with 8 oz strapped to the nose as there is no official COG supplied with this plane. After a few feet she was in the air and a couple of clicks on the ailerons and elevator she was flying true, a very easy maiden. Found with the large control surfaces that she was very sensitive on the ailerons even with 60% expo but nothing I could not handle. Flew her inverted to check COG and she headed for the ground, decided to land and remove the 8 oz up front.
Second flight found that she flew straight and true with no weight added to the model at all, just like the sbach did, perfect. Tried to stall her 100 ft up into a 10 mph wind, I throttled back and with the slightest of up elevator watched her sit perfectly in the sky, did not drop a wing at all, just sat there not going forward or back. Infact im sure she started to climb in this horozontal position!. had a few low flybys and found her to be very stable at walking pace into the wind, far more stable than the sbach with no sign of wingrock at all, this was the experience I was hoping for with the sbach but it did not deliver. The Yak is much happier at stall speeds and does not threaten to torque roll the same when you add sharp power.
Third flight I had a dead stick above the middle of the runway with the dle 20 at 50 feet in a hover position , was no problem gliding her in. Tweeked the engine.
Forth flight she deadsticked again 70 feet above runway, miss judged the landing and realised I was going to run out of runway and end up in the trees, forced her down and it was not pretty, totally thought I had damaged the fuse but found I had only flattened the landing gear, was suprised the model took the hard landing, think I was very lucky that it did to be honest. Spent a long time tuning the dle 20 before next flight.
Fifth flight she sounded great in the air, good transition, no gurgle and then deadstick? Landing was easy. Decided to call it a day after 3 deadsticks while the plane was still in one piece.
Not sure what is going on with the dle, not new to gas but struggling to get her to run reliable, can tune her rich on the bottom so she wont deadstick but it means she fourstrokes at idle and gurgles and chokes up below half throttle, no use to me with a model as light as this as cannot hover with a chocked up motor that suddenly clears and goes vertical like a bat out of hell. Tweek her for max rpm and thin the bottom end for good transition she seems fine but then without warning quits?. Got a few things to check out and if all fails im sure I have a walbro 793 lying about somewhere that I can try.
Anyway to sum it all up I would say im very happy with the way she flew, at 7 pounds 9 oz dry she has a wing loading of about 17 oz/foot and flys really well, a very good wing loading for a 3d arf/dle 20 combo, maybe not as good or strong as a kit built profile but for a plane you can throw together in a few days she is great fun. I will post a picture of her at the field and a couple showing the motor mount position and glassing and tri stock I added that I think is still required to handle the dle vibs. The picture makes her look quite small but it is a illusion as she is longer than the sbach and has a much wider wing, it is only slightly smaller than my 30cc pilot yak.
Posts: 3
Score: 100 Joined: 9/7/2010 Last Login: 11/1/2012 From: Peterborough, UNITED KINGDOM Status: offline
Hi, I'm in the UK also. Where did you get this model , and how much was it if you don't mind me asking. I would like something like this for one of my DLE 20's.
Its a chinese based company, this is the second plane I have bought from them. Comes well packaged and expect 7-10 days for delivery.
The price on the website is what you pay in otherwords it includes postage and customs charges. I payed £192.85 for mine, it is at £197.85 just now. Not cheap but if you dont want to build a mojo 65 and want a profile arf that flys well with a 20cc gas this is what you may need to pay in the uk.
Posts: 434
Score: 142 Joined: 9/5/2009 Last Login: 5/9/2013 From: stirling, UNITED KINGDOM Status: offline
Got this model back to the field again today, have fittted a cm6 spark plug and made sure it was well gapped, I normally fit a cm6 as standard to my gassers but got lazy with this engine. Spent a tank tuning for perfect throttle response and peak rpm then gave the bottom and top end a 16 th extra towards the rich side and flew her again. Well she flew great, amazing in fact, I was worried about this yak having balance/coupling issues compaired to the sbach well I should not have worried this plane flys so well it makes flying easy. She pops into a hover with ease and holds it blipping the throttle 25%, half throttle for pull out as full thottle is just to much! The ease of holding a hover with this model is also a suprise, im used to throwing the sticks everywhere trying to balance a model in the hover, this thing just locks in, very easy. There is no knife edge coupling and the model flat turns with the rudder perfectly, very nice. By far the best flying model I have, very suprising for a chinese effort.
I noticed on the flight line waiting for take off that at idle just at a certain rpm the fuel in the tank foamed up completly due to the vibes, this may have been why I had so much trouble finding the sweet spot on the carb tuning as this allowed air into the carb feed line, though the plug replacement seems to have sorted the running I decided when I got home to ditch the solid fuel tank clunk supplied and fit a foam filtered one to help with drawing air due to foaming, I also added a bit isolation to the fuel tank by fitting a bit foam between the fuse and tank, I strongly suggest this is done to increase reliability.
Posts: 434
Score: 142 Joined: 9/5/2009 Last Login: 5/9/2013 From: stirling, UNITED KINGDOM Status: offline
If you fit a dle 20 and fit the battery strapped to the wing tube in one of the wings she will be perfectly balanced. Would need to put the model together to check exactly the cog ended up but im pretty sure its about 3/4 inch behind wing tube.
Posts: 9
Score: 100 Joined: 2/20/2006 Last Login: 3/23/2013 From: kinightstown,
IN, USA Status: offline
Thanks,
It felt a little tail heavy so i made thefirst flight with a 2 oz prop hub, but found it was not required. To be honest i did not have the highest expectations for this plane, however it performs very well with min coupling. Im more concerned the dle 20 is going to shake it apart before it breaks in. For a $169 hard to go to wrong.
Posts: 434
Score: 142 Joined: 9/5/2009 Last Login: 5/9/2013 From: stirling, UNITED KINGDOM Status: offline
Make sure you add tri stock where you can to the motor mount as it possibly will shake itself apart. I believe the manufacturer is supplying a bit tri stock and a note to fit it on the latest models.
She does fly really well, was expecting loads of power to weight to practice hovering but was not expecting such a great acrobatic performance from this bird but she tracks straighter than anything I have flown, knife edge or inverted, great flying model.
Posts: 12086
Score: 247 Joined: 1/25/2002 Last Login: 5/19/2013 From: Hesperia Michigan,
MI, USA Status: offline
Where can a person find some photos of how the reciever, servos, batteries are installed in wing. Or maybe a link too where this data can be found. Thanks Capt,n
Posts: 9
Score: 100 Joined: 2/20/2006 Last Login: 3/23/2013 From: kinightstown,
IN, USA Status: offline
Not sure how everyone else mounted the rcv but i used velcro to mount it in the fuse in the canopy area lead side down. I then put the sw, charging jack an a123 in the root of the wing opposite the engine jug and ignition module static balance is very close. With this setup if i take the wings off there is only three leads, and i can charge the battery in the wing while the wings are off.
I will shoot some pics when i get home late this week.
Posts: 1396
Score: 166 Joined: 7/5/2004 Last Login: 5/17/2013 From: berlin hts,
OH, USA Status: offline
thanks for the info on this model.always wanted to know how this new plane flew.when my OMP Fusion takes a dirt nap i will be looking to replace it with something like this.dosen't look like we will be able to buy the Fusion anymore.
Posts: 1869
Score: 669 Joined: 8/10/2008 Last Login: 5/19/2013 From: Waterford,
MI, USA Status: offline
quote:
ORIGINAL: captinjohn
Where can a person find some photos of how the reciever, servos, batteries are installed in wing. Or maybe a link too where this data can be found. Thanks Capt,n
Capt'n,
I have an OMP Fusion, but it has to be pretty similar? No pics, but it's not that complicated? I have the receiver mounted in the fuse, in a location where the cut outs in the inboard wing ribs fit over it when the wings are installed, if that makes any sense? Clear packing tape holds it centered within the fuse/in place, yet allows for easy service if necessary.
Running dual batteries, through 2 switches, then through 2 "Y" harnesses that are also connected to the aileron servos. One set in each side (battery, switch, Y harness, aileron servo).
Field setup has me plugging in a connection going to each wing, then installing the wing bolt. That's it. All of it is concealed. There's a power switch in each wing. Ignition is run from the receiver bus (Y harness in throttle servo) as well.
Posts: 507
Score: 111 Joined: 11/23/2002 Last Login: 4/12/2013 From: Rapid City,
SD, USA Status: offline
quote:
ORIGINAL: raydar
Make sure you add tri stock where you can to the motor mount as it possibly will shake itself apart. I believe the manufacturer is supplying a bit tri stock and a note to fit it on the latest models.
She does fly really well, was expecting loads of power to weight to practice hovering but was not expecting such a great acrobatic performance from this bird but she tracks straighter than anything I have flown, knife edge or inverted, great flying model.
Here is something else you may want to make and install on the engine mount. I have been making these for every profile I have flown for the past 15 years. The alum. straps spread the load and keep the washers from ruining the engine rails over a long period of flying time. These are also sold by Aerobeez. Here are a couple short video's of mine First the normal take off I do http://www.youtube.com/watch?v=P8LyDsH9eFg&feature=plcp , and second is how I usually land it on a gusty windy day http://www.youtube.com/watch?v=mITfeMbM3co&feature=plcp I have two of these from Aerobeez One with a DLE 20cc and the other one has the new Mintor 22cc. Both have profile style mufflers. The DLE I had to buy one for made by J'TECH. The Mintor 22cc was ordered with the CNCed profile muffler no extra cost from Top Dawg Aviation I have also assembled 3 more of these yak's from Red wing RC. They were bought before the price went up the end of July for 135.00 ea. They all come from the same factory in china I believe there are 4 or 5 Co. importing these 20cc Profiles, both the Sbach and the Yak 54 both are awesome flying profiles the Sbach is not as forgiving as the Yak .here is the one with the Mintor 22cc first 8 oz's of fuel ran through it to set it and go fly http://www.youtube.com/watch?v=bd-7Ibi85lE&feature=relmfu
< Message edited by jerrysu29 -- 8/29/2012 10:15 PM >
Posts: 507
Score: 111 Joined: 11/23/2002 Last Login: 4/12/2013 From: Rapid City,
SD, USA Status: offline
I am far from being a great 3D pilot but I keep practicing. Thanks Ernie for the nice comment. When it is calm I land the same way I usually take off, but I guess it is frond upon by many.
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