bob27s

My Feedback: (19)

Start off light on the prop APC 9x7 or 9x8 let it turn up

After you get some time on the aircraft you can try a 10x6 as well.

Find ground peak rpm briefly, back off 800 rpm for flight.

Make sure you have good cooling paths for the engine and the muffler. Keep the left side "air inlet" closed off.

camdyson

From memory it's a GP spinner - I swiped it off one of my other planes. Kit one looked a bit weak for the abuse it's likely to get...

ErikElvis

My Feedback: (2)

I dont think the 91 surpass is that big of an engine considering it flew my minnow "ok" for an 8lb plane. So if this downer comes out to 7lbs it should be quick. Only prob is its a lil stumpier than the minnow so balance might be a bit of an issue. Please let me know how it flies with the 91 Cam. Im thinkin it should be a fun plane. Your cowl looks great. Only thing is I might route the exhaust out of the cowl. It looks like I should be able to take it on and off w/o the cowl interfering.

camdyson

Just assembled tonight to check balance - looks like it will need a biggish battery pack behind the wing TE as suspected. I've got a 3700mAH NiMH pack lying around so will cut the covering off the bottom of fuz behind wing and figure a way to support it in there.

May get it done for a weekend test if I keep at it.

Cam

BTW my muffler has a silicone extension and exits the bottom of the cowl roughly central. Cowl is only impeded by needle valve.

camdyson

Well, flew her today. Most time was spent re-tuning the OS, initially with an APC 13x7. Tuned to around 10,300 rpm which was still on the rich side. Balanced per the manual, with all throws per the manual and 50% expo on all flying channels.

Flew really smooth, and moderately fast, with the high rates just comfortable - a bit more throw on the ailerons will be dialled in. It was tricky to slow down on landing as expected, and a go-around became a landing after throttling up too quickly cut the engine. No probs, (despite the best efforts of the boundary fence...) but will go over the plane before trying a few more props and leaning her out a bit more. Plan to try a 13x8 next for a bit more speed, suspect it may over rev on the 12x7 I have.

The OS 91 FS II is fine in this plane if you're prepared to mount a biggish battery pack behind the TE - I added no weight at all except to a wing tip.

Cam

ErikElvis

My Feedback: (2)

Glad to hear cam. Didnt see that you flew it. I was running a 13x9 with the minnow. It flew well. It started with a 14x6 and was butt slow. Tried a 13x8 at around 9600 rpm's. then the 13x9 gave me about 9400. didnt really notice a difference between the two but droppin to a 13in prop helped a lot.. I might try a 12x10 when its on the downer. If I can keep the revs to around 10k it should fly nice.

ErikElvis

My Feedback: (2)

Hey Cam! anymore updates on the flyin? I hope to get mine built and in the air before winter.

kmac425

My Feedback: (82)

I have an Italian ST.75 that might go well with this sundowner. I've been wanting this little speedster for awhile now. Would the ST .75 be an alright motor to zip it around pretty fast?

kmac

camdyson

Sorry, haven't checked in for a while. Haven't been flying due to crap winter weather here. Hope to get out next weekend if things improve. (Did manage to finish my B25 though )

Cam

nesikachad

Sooooo if a OS9 04s is great, then a YS110 should be AWESOME?

Please say yes!

russm

worth a try. lot of reinforcment up front.

camdyson

Think I read somewhere in another thread it's been done, and yes, twas awesome.......

mk1spitfire

which is a better plane, the kelly or sundowner?

nesikachad

I plan on finding that out here this fall.

Have the little SD in the box and a Kelly will be ordered just as soon as I get home from overseas.


One last question. Regarding the YS motor. This is going to sound dumb (I'm such a newb) are we talking YS 4 stroke or two stroke?

I have a 4 stroke on my Funtana 90X. That's the only YS product I'm familiar with.


Be gentle. . .

ErikElvis

My Feedback: (2)

Im fairly new to all this as well. But I believe YS only makes 4 strokes. And nasty ones (in a good way) at that. I can not wait to get that YS slapped in the minnow. The YS110 is a smaller engine for its size but man I think it would be tough to put it in the downer. The 91 4c doesnt have much room to play with.

nesikachad

Thanks.

I ended up ordering a Jett and it should be in the mail and delivered by the time I get home (three weeks!)

I have a question regarding this little thrasher. With all this added horsepower and speed we are cramming into this airframe, should a guy be looking at servos at all? The manual advocates the JR sport digitals. Has anyone had any issues with flutter or lazy response when punching 130/140 mph holes in the sky?

I'm just curious. I had my first experience with flutter last spring. My Funtana with a YS110 tore half of my elevator off during a momentary full power dive. I was amazed at how little time it took to do this. Really made a mess of things as it stripped the gears out of my servo too. I saved the plane and landed successfully, but it was sobering and now I'm a bit paranoid.

I intend to rig up a pull/pull for the rudder and to upgrade the elevator linkage a bit as well. That long wire stuffed through a straw just seems a bit on the weak side to me. More experienced modelers here feel free to chime in if I'm being dumb about this.

Anyways, love this little bugger and can't wait to get home and get after building/flying.

russm

the control surfaces on this plane are small. i am useing hitec 422bb`s and have had no problems. have around 75 flightson mine,most w/ the jett 90lx. that said, better servos can never hurt.

bob27s

My Feedback: (19)

does not need anything special for servos.

Stock pushrods are ok. A solid metal rod is hard to beat. And after seeing a few carbon rod/rod ends come apart recently (albeit probably incorrect assembly) I'd keep it to something tradition that is known to work. You can't pull the end off of a solid rod.

Keep it simple. Just be sure to seal the control surface gaps.