Airnondas

My Feedback: (6)

Hi Shayne

I have read every post here on the Sundowner.

While everyone has a right to their own opinion, it is obvious that some people may interpit or misinterpit some of these views.

The information I get here on RCU is very valuable to me because it helps me in better enjoying the best hobby in the world.

The reason it is the best is because it is fun, the day the fun stops is the day I will look for a new hobby.

This link is to a earlier post that shows a small clip of me having fun with my smaller racing plane called the Alley Cat.

I have had a lot of practise with this plane and because I loved the way it carved the sky, when the Sundowner came out, I could not resist getting it.

Soon I hope to have a link to a video of the Sundowner maiden including the dead stick landing.

Here is the link to the Alley Cat video.

http://www.rcuniverse.com/forum/fb.asp?m=6333047

___________________________

Airnnodas

JoeMamma

Subscribed

GR7Racer

Hey guys...just thought I'd chime in with a little of what I've learned.

I've been flying mine with the Evo 35 and doing some testing for the racing series. I'm at 13.65 lbs dry and with a 16x14 APC prop I'm getting 7850 on the ground and about 108mph in the air. Speed is via radar gun at the end of a long level pass...no diving energy.

This setup has decent flying characteristics, but you can initiate a high-speed snap that will bite you if you are not careful. Landings are a little hot, but the airplane will slow down if you work at it, it just takes a little more distance/time to do it.

I think many of the mixed feelings and different opinions on this airplane are due to various setups that are being flown. It's my feeling that these opposing views are probably related to wing loading. The Evo35 and its ignition system weighs 3.9 lbs without muffler and mount, and like I mentioned that gives my airplane an all up weight of 13.65 lbs. If you put a Saito 180 in it that only weighs 1.9 lbs, you're going to be 2 lbs lighter! That will greatly effect the flying characteristics of the airplane. It will surely be less likely to snap, and should slow down more before stalling.

I hope everybody who is considering this airplane will think about what they want in the airplane. If you feel like you can handle a higher wing loading racer, then pick whatever power plant will give you the HP to go the speed that you want. If you are a newer pilot (not a beginner) and might not be as confident, then pick a lighter engine so the airplane will fly better.

We plan on doing some more tests this weekend with an airplane that is over 1.5 lbs lighter than the one we are testing now, I suspect that we will report back that the airplane flies even better at this weight...we're thinking that it will be just as fast too.

KennyMac

bzyguy01

I agree with your theory...Mine is on the light side with the OS160 and I feel like I can float mine somewhat easier than others with the heavier wingloading. Mine is alittle more tame??( is that a good term?) than the heavy ones that I've seen fly.

GR7Racer

Hey Bzyguy....

Is that the OS 160 4 stroke or 2 stroke?

KennyMac

bzyguy01

Hey Kenny, Its the 2 stroke.

vince.b

My Feedback: (1)

GZ7 racer... see now thats an intelligent post/ reply.
I made a post here about trying a DA 50 and someone replied that the extra weight would destroy it. Turns out that the DA is a pound lighter then the EVO.
My 3rd plane was a super sporter 60 with mods retracts knuckle hinges and a tight cowl sheeted wings. This hit the radar at 119mph on multiple passes. If you know the plane, this bird in know way has a fast wing.
I had this plane about 14 years ago. This is why I am looking at the DA50 or the ys for the cool looking plane. If I am building a nice looking plane I want to be able to open up the throttle once and a while and push the 120+ mark. Bring back the old days of 6'' off the deck 120 passes and slow rolls.
THe plane should be here today so I will know more about the cowl mods or it just might be the YS unless anyone knows of a stronger nitro engine.
anyone out there using a YS dz160 or dz170. Is the YS stronger then the EVO?
by for now

bzyguy01

Hey Vince....I'm going to try and give my 2 cents for what its worth as It's about all I have [] My OS 160 2 stroke is lighter and makes similar power if not more than the EVO gasser. Regardless of what the specs say....Cuz in real life results that I'm comparing to I'm pulling the same 15X12 at a higher static RPM and I'm using a "W" prop. My straight and level flights are pulling 125 MPH on radar with no dive inertia and others with the evo on radar are only pulling 109 to 111? I did not radar their planes but I pulled those #'s off of another racer forum for the SD. I thought I was going slow untill I compared their setup with the EVO. Still not fast enough for me tho...Guys with the Moki 2.10 are telling us that they are flat getting it but I have not heard of their radar results as of yet. I would think it would rip with the 2.10 moki tho. As far as YS I have zero experience with that engine?? Sorry. And as far as the DA.....I'm with you here.... It's your bird...use your own judgement as to if the construction in the bird will hold up. I think that the guys said not to do it because of the liability....on anyones part. And thats cool but it's your bird. I'm not saying do it or don't but if it was mine and that was what I wanted....Nobody's gonna stop me right or wrong. What do you think the replies the guy got that said he was going to build the first real turbin jet RC plane??? Yeah!
AS always...Keeping it real

Shayne

GR7Racer

Hey vince....

I'm afraid I fall into the camp that would discourage you from using the Da50...but myself and others here are only trying to give you our opinion and share with you what little knowledge we have about this airplane so that you will have an enjoyable experience with it. Not trying to harsh your buzz.

I also fall into the camp that supports your right to GO FOR IT!.......so with that said, knock yourself out!...not literally of course!

Good luck

KennyMac

vince.b

My Feedback: (1)

Thanks
the thing is i have the DA and lots of time on ys 90 2 stroke Heli engines not to mention about 80 gallons of 30%.
even though I dont own a YS 4 stroke i know lots about them.
The DA is in a great planes pits and my bet is that it can do 100+.
one big thing to, is at our field planes need to be as quiet as posible. Its easy to make a large power plant fly quiter than a smaller one quiet thats always firewalled
is that os 160 on a pipe and what fuel are you burning ?

bzyguy01

My OS is not on a pipe, I'm using a pitts style muffler with the reducer tips cut off and I'm using 30% Heli Cool Power I'm having issues getting enough fuel to it at WOT but I think I have that corrected (I think) I'll test this weekend and post my results. I'm putting a pump on the system...I didn't want to add back pressure to compress the tank Psi because I would loose around 400-450 rpms as that is what that engine gained by removing the small exhaust tips but it obviously also lost the required tank psi to properly fuel this beast at WOT, so the pump was a easy decision.
I'm also not sure that I will stay with the 30% heli as I'm still testing things.
Shayne

PS....KennyMac....That was a good post!

bzyguy01

[quote]ORIGINAL: vince.b

not to mention about 80 gallons of 30%.

Ummm....Am I seeing this correctly! Holy Moly...I thought I had a problem!!! Your my Idol!

vince.b

My Feedback: (1)

2 strokes are so sensitve to back preasure.
the right header and pipe can add between 20-30% more power.

thunder34

Hey guys keep those great posts and replies coming. I love it!!!! I'll be flying soon.

CRG

My Feedback: (3)

Hey Vince,

Not sure who said that the weight would destroy it, but in one of my earlier posts I was implying that the power might be too much for it, not the actual engine weight. The DA50 and EVO 35 are actually very close in raw weights, both a little over three pounds. No question the DA makes a ton more power than the EVO. And I'd agree with KMac, if you want to use the DA go for it and good luck. I still wouldn't recommend it but will stand up for your right to do as you choose.

Sounds like the OS 1.60 and Moki might be the stronger nitro choices so far. I have a Sundowner here with a Super Tigre 3000 in it. Weighs around 11lbs 14ozs. ready to fly, will take it out Sunday with KMac and fly it against his EVO powered version. He should have his radar gun with him so we'll get some speeds on it also. I had one with the EVO and it flew great, this one is an experiment to see how much better if any it flies with a pound and a half out of it.

120-125mph is not unreasonable for this airplane and we'd love to find an affordable package for new racers that will achieve those speeds consistently.

Craig.

bzyguy01

CRG...I'm looking forward to you report...I hope you and Kmac have sucess with that setup! That would be a very easy and cost effective alternative. I'm very anxous to test mine with the pump setup!
Shayne

bzyguy01

I also have to admit guys.....I kinda want to do a DA 50 also!!! Only now I would need to start saving my milk$$$.

CRG

My Feedback: (3)

Will definately post a report here after we fly it. The motor is an old 3000, they don't make them any more. Actually it's never been run, but is more than 10 years old. The 3250 should drop right in also, and is great value at $179.

Craig.

FlyerRick

Hey Guys...great posts here, well bzyguy01 my new "Downer" is in stage 2 of the building process, just got my BGX 3500 back from the "Trick Shop" it's ready, so it won't be long and I can't wait...AGAIN! [8D] Really like the idea of the pump. I was going to use it on the last go around but didn't. I definitely will this time. Gotta work Sat but good luck and I will see you Sun if you make it out to the field...

Again, great posts and info here guys...gotta luv it!

vince.b

My Feedback: (1)

I probable read it wrong. All I saw ws the extra wieght would desrtoy it.
The Moki if it works would could be the best cost to speed ratio because its desiegned to run on FIA fuel, but the guys that ran then used 5% with awsome resalts. They used them in formation scale arobatics.

Kcripto

My Feedback: (1)

Here my Sundowner with Moki 2.10:

bzyguy01

Kcripto.....Badd *****! I like! I also like the way you drilled some weight off of your mount....

4 more flights today and I'm finally done and going to leave it alone now
The Oscilating Perry pump was the fix....without a doubt. Temps came down and the engine produced a very light hint of a smoke trail at long wide open passes at max temps that never exceeded 285Deg w/ 25% Cool power. The MPH's were a consistant 122-124 MPH and it didn't gain anything except hotter temps with 30% heli. I'm also going to stick with the 15X11 APC. This prop also helped keep the noise level down when compared to the 16X10 that had the tips going supersonic. I'm happy for now. Where were you Aerozona??
Shayne

vince.b

My Feedback: (1)

"it didn't gain anything except hotter temps with 30% heli"
if you left the needle the same it would be lean when you move to higher nitro contet.
More nitro mean more o2... @ 30% nitro there is 66% more o2 in the cumbustion chamber. Thats why they call nitro liquid horse power.
good heli fuel also uses low viscosity oil because of the higher rpm heli engines 16000 and higher. But i would think any nitro engine would run better on high quality oil.

Kcripto

My Feedback: (1)

yes, not too much but a little... also I use a carbon landing of Funtana 90 short version by graph tech, is a little more tall and give more prop clerance.

Rebellion

My Feedback: (2)

Very nice Kcripto. I think I'll follow your lead and drill the engine mount out a bit.

I'm using the same Moki / Bisson muffler as yourself and I'm curious if your muffler is as tight a fit as mine ( see pic below ). I'm going to take some measures to make sure the cowl doesn't get heat damaged.