Author Topic: Done at last! Sky Streak finally made it to the top of the food chain! (Read 5109 times)

Larry Renger · « **on:** February 02, 2011, 09:14:27 PM »

After being shuffled aside by other projects, I have finally finished the Sky Streak. This is a forward swept flying wing stunter with 250 sq.in. wing, weighing a scant 6.8 ounces! I have had two prior models in this series, and they both flew great. This one is bigger, lighter and with more power. What's not to like?

Power here is an AP Wasp .061 with the Holuszko venturi and Merlin plug. Prop is an APC 5.5x2.5. It has an internal balloon (baggie, not pressure) tank inside the cowlings. I expect to fly it on about 45' x .008" lines. It certainly will be capable of a superior pattern flight in the right hands (not mine, Designman, you know, not Pilotman

)

Covering is Coverlite, paint is Rust-O-Leum. The stripes are very old and will fall off soon, but I really wanted them for the photos. The lettering is done with hand-made stencils as outlined in the building forum (or the paint forum? one or the other)

Balance, currently, is just ahead of the high-point spar at the 3rd rib, which makes it just ahead of the leading edge of the wing root. Hung by the leadouts, it is just barely nose down. There is no engine offset and minimal rudder offset. If you keep the speed up, and use light lines, they just aren't needed and will actually degrade competition performance.

Oh, and I plan to publish the design, probably in Flying Models, then RSM will likely kit it.

Bill Barber · « **Reply #1 on:** February 02, 2011, 10:08:36 PM »

Larry very cool , can't wait to see this one fly !
Bill

PJ Rowland · « **Reply #2 on:** February 02, 2011, 10:26:51 PM »

Awwwwww so little.. Like a kitten

Larry Renger · « **Reply #3 on:** February 02, 2011, 10:38:20 PM »

Larry very cool , can't wait to see this one fly !

Me too!

Dennis Adamisin · « **Reply #4 on:** February 02, 2011, 11:01:32 PM »

LOVE IT Love teh built in battery box too...!

JamieHolford · « **Reply #5 on:** February 03, 2011, 10:45:35 AM »

,Now that is cool!

Dennis Saydak · « **Reply #6 on:** February 03, 2011, 01:25:42 PM »

Quote from: JamieHolford on February 03, 2011, 10:45:35 AM

,Now that is cool!

Yes it sure is. I think Designman needs to change his name to Larry The Coolman.

Jim Thomerson · « **Reply #7 on:** February 03, 2011, 02:24:00 PM »

Very nice. You are going to encorage me to do a wing design.

Larry Renger · « **Reply #8 on:** February 04, 2011, 09:23:25 AM »

The swept forward wing does a variety of good things. First and formost, the tips will not stall, so you can drive the wing to maximum lift and get the use of the whole area. Second, it allows you to have the tank and engine ahead of the wing while still achieving good balance. Third, the wing acts like a normal aspect ratio regarding lift, but a very low aspect ratio regarding dampening of oscillations. Fourth, you geta good working moment for the elevator, so it need not be large, and only degrades the center section performance a little. It also effectively reduces the angle of attack at the center so it doesn't stall either (if you get the geometry right). Finally, it looks way mean in the air!

Allan Perret · « **Reply #9 on:** February 04, 2011, 02:29:35 PM »

This must be one of those optical illusions; looking at the rear view.
Ribs on the left wing panel look like they are parrallel to the fuse.
Ribs on the right wing panel look like they are perpendicular to LE.
So how are the ribs layed out ?

Larry Renger · « **Reply #10 on:** February 04, 2011, 11:06:44 PM »

I am not sure what you are seeing, but the ribs are all parallel to the fuselage, and the spars run parallel to the leading edge.

Maybe the decorations are throwing you off. The wing sweeps forward at about 10 deg. so if you think it is straight, of course the angles will be off.

Dennis_Langworthy · « **Reply #11 on:** February 05, 2011, 05:11:08 PM »

It must be the angle of the picture, because I see the same thing Allen does. It looks like the ribs on the near side are 90 degrees to the leading edge and spar, but the far wing looks different. Very cool looking plane, I think there might be one in my near future. Thanks for posting and getting my building juices flowing

Larry Renger · « **Reply #12 on:** February 05, 2011, 07:31:32 PM »

Purely an optical delusion caused by the wing angle and the paint scheme. Now that you mentioned I can see the illusion. However all ribs are exactly parallel to the fuselage.

Dan Bregar · « **Reply #13 on:** February 18, 2011, 06:22:36 PM »

Larry, your Sky Streak is very cool. I'd like to learn more about the Rustoleum paint job. My understanding is the Coverlite just irons' on and no paint goes over it. So you painted the fuselage and part of the center section with Rustoleum. What did you put on the bare balsa ?

Larry Renger · « **Reply #14 on:** February 18, 2011, 09:48:59 PM »

Thanks for the kind words and interest!

I masked off the area that the Coverlite would cover, then used brushed-on water based Urethane clear, several coats on the remaining balsa. Sanded lightly (400 grit) between coats. The Coverlite is adhered with Balsarite (smuggled in from Tucson!

) and ironed on. Then the plane was masked off and one coat of Rust-o-leum white for the canopy. That was allowed to dry, then re-masked for the dark red Rust-o-leum. The stripes are Great Planes striping tape. The lettering is black Rust-o-leum. In a thread in finishing (or building?) I outlined how to do stencils with stick on shelf paper.

Larry Renger · « **Reply #15 on:** March 26, 2011, 02:29:31 PM »

It's ALIVE! The Sky Streak finally took to the air today. Two successful flights. Smooth as glass. Too smooth in fact, to the point where it wouldn't do more than casual climbs and dives.

I increased the control throw and added some tailweight. This time it would do big loops and fly inverted. More trimming needed, but the potential is there!

john e. holliday · « **Reply #16 on:** March 26, 2011, 08:14:39 PM »

Went back and looked at the pics. Looks great. I am sitting here trying to catch up on two weeks of messages. Don't like flying in freezing temps anymore with snow flakes falling. Did go to the grandsons Pine Car Derby. He would not listen to my advice on doing the car or the finish. He got first place in his Cub group and third overall fast time. The electronics they have for timing the races. Witnessed a crash as about the time the cars got to full speed a wheel came off one car. Took out the car next to it also as it left the track. They got a rerun. Thinking of getting some platters ready for the .049's to let the cubs try and fly.

Now did I say I like the looks of the plane. Hope it isn't too long getting to production.

Larry Renger · « **Reply #17 on:** April 03, 2011, 06:52:27 PM »

Latest news. I had the model out on Friday, sitting innocently in the pits, when the lines got snagged by a .65 powered stunter. Guess who won?

Trashed the lines, of course, threw the model 15 feet, landing upside down at a fair velocity. It was NEW and pretty! Why ME???

Got it re-assembled, and flew it this morning. The trim is getting WAY closer. This will be a real sweetheart when it is trimmed.

On 48' lines and 10% nitro it is way too fast! I will have to drop down to a 2" pitch prop to get the lap time reasonable. As light as the model is, I don't want to go to longer lines.

This one will be totally competitive for 1cc stunt. Actually it will be totally competitive for any profile stunt event or PAMPA up to and including Advanced. I may just have to scale this up!

Larry Renger · « **Reply #18 on:** April 03, 2011, 06:58:14 PM »

Doc, I have done the coaching Pinewood Derby thing myself and there are some really sneaky, go-fast tricks to do. Do you think we should start a thread? and if so where?

My sons took first and second, and the "group" car came in third. Bwah haaa haa haa!

Larry Renger · « **Reply #19 on:** April 26, 2011, 07:31:33 PM »

Finally got ahold of the #2 Frite Streak and took a "family photo". The small one is a modified Brodak Lightning Streak kit powered by a Golden Bee. Nice flyer for BIG maneuvers, but will do everything. The other orange and black one is larger and scratch built. It uses a Black Widow for power and will do a sufficiently good pattern that I took 1st in 1/2A stunt at Woodland with it. (3 pit stops, 1 second to spare in the 8 minutes!) The third time is the charm, however and it should prove to be totally competitive. 150, 180 and 250 sq.in for the 3 models and #3 weighs barely an ounce more than #1!

Larry Renger · « **Reply #20 on:** April 30, 2011, 05:09:33 PM »

Yes it flies!

No photoshop creativity other than cropping and resizing for publication here. The pilot shown is not me with liposuction and hair transplants, it is the one, the only (thank goodness) Antone Kephart! Antone has won the Leprechaun Pot 'o Gold trophy for the last 2 years, so I could easily trust him to fly the plane while I shook...umm..took photos.

Steve Helmick · « **Reply #21 on:** April 30, 2011, 08:22:47 PM »

Good lookin' plane, Larry. I'd get in line for a .40/.46 sized version!

Steve

Larry Renger · « **Reply #22 on:** May 02, 2011, 09:30:24 AM »

Well, I don't have plans for this one in 40 size, but how about a Slyfire?

Larry Renger · « **Reply #23 on:** June 19, 2011, 09:46:10 PM »

Trim on the Sky Streak is getting VERY close, and switching away from trike LG has fixed the landing problem. I should get the article off to Flying Models very soon!