Stingray Construction
 

Yeah........ What he said, AND nuthin' but NET! LOL

Stingray Construction
 

Good catch Terry! Did not even notice it read like that.

Chris

Stingray Construction
 

Help!!! Ive got to the plumbing the tanks stage and im stuck.

I thought i would parallel plumb them with a Y lead. Tried that but when i tilted the tanks on the test stand, they drew air in and the turbine stopped. ( i am planning on using a UAT but i wanted to test it without first of all.

I spoke with my turbine manufacturer and they told me i had to use series tanks, not pararllel. Ive tried this but i found when defuelling the tanks to simulate running the engine, the tank nearest the pump compresses down as if the fuel isnt leaving the second tank fast enough or as if there was no vent, which there is otherwise the secon tank wouldnt fill.

Im at a bit of a loss now, so would appreciate knowing how you guys are doing it. Oh and i had tried the metal clunks that came with the kit, but was told by wren to use the felt clunk.

Help please!!

Fuel cells
 

I know that Gary at Jet Tec makes a set of kevlar tanks for the stringray and a BVM UAT tetween the wheel wells.
Paul JPOFL That works on mine well!

Stingray Construction
 

I used 3/16 brass tubing and metal clunks in my main tanks and then the paper filter clunk in a 2 oz header. Mine are plumbed in series, it has only flown once with no problems, hope to take it up soon. I used my fuel can to leak check the tanks and did not notice and swelling or contracting of the tanks and that pump pulls a lot harder than the turbine pump. Good luck.


Chris

Stingray Construction
 

Strato, where did you get those fantastic straps that are holding down your turbine? Thanks.

Stingray Construction
 

The straps are from yellow aircraft.

Chris

Stingray Construction
 

I finally solved my fuel tank problem. I had to use 3/16 tubing on the vent from the first tank and then the BVM UAT tubing to connect the tanks together. I then used the 3/16 tubing on the second tanks clunk and vent line.
I can now defuel without the the restriction to fuel flow in the connecting line making the first tank deflate.
I kept the original piping inlcuded witht he y/a tank in the clunk line of the first tank.

( Did that confuse anyone??)

Anyway ive now mounted the tanks in the fuselage, i used ca at teh rear bulkhead and hot melt glue in a ridge at the front.
I am concerned about the hot melts strengthe and stickiness at temperature but right now i want to see the fuel setup work and have the option to remove it if there are problems.

Stingray Construction
 

A lot of UAT Users out there consider this massive deflating and expanding of the UAT to be "Normal". I've always known what you found out that we are simply pushing and pulling more fuel through the system during fueling faster than we are replacing and/or moving air out/in. I've considered initiating a thread on this issue, but I was going to take the time to run my own tests prior to posting. Sounds like you beat me to it. Now that you've got more access to air, are you still getting any compression or expansion in your tanks?

Stingray Construction
 

Seanreit,
I havent actually plumbed in the UAT yet. The tanks i was referring to were the 2 1l y/a main tanks.
I used the kavan pump which i gather can deliver 1.8l a minute so i was fuelling and defuelling faster than the turbine fuel pump ever would ( the wren takes 240ml/min at full throttle).

So during defuelling, There is still some cpmpression of the first tank, but nothing like what there was before. And whenever the clunk in the furthest away tank is vented out of the fuel,as it may be in a bank, then the first tank isinstantly reinflated. Before the air really couldnt get through.

It just unfortunate i dont know of anywhere to get more og the BVM UAT piping. It fits great onto the 3/16 brass pipe i have

Speed brake help please!!
 

Hi guys, i hoping to get some photos taken ad then develpoed this weekend. Posting some may then be an option!!

Im now at the speedbrake stage, Ive just glued on the hinges and tried them in the recess of the fuselage. Unfortuneatly the brake will then not deploy without diggin into the front of the speedbrake opening. Almost as if the hinges are not far enough rear on the speedbrake.

Did any of you have similar problems? Those of you who went the conventional way with the speedbrake??

Stingray Construction
 

Hey Chris,
Just finished painting my stingray today! I hope to fly in the next week or so after I chase down a gremlin in the retract air lines. :rolleyes:

Kelly

Stingray Construction
 

Very nice! I have not flew mine since the maiden. I had to put different wheels on it, just finished machining them today and got the tires mounted, All I need to do now is mill the brakes out to fit the struts and I am set!

Chris

Stingray..... speeeeeed !!
 

Hi all, good informative thread. I don't have a Stingray, though I have to admit to being tempted. I saw one flown at the Weston Park airshow here in the UK some 3 weeks ago, with MW54 power. Asolutely ballistic !! Not sure if it is somthing to do with the airframe's smaller size but near enough the fastest thing I've seen in a long, long while. Would be interesting to record the actual top end airspeed on one. I think all of the construction mods and landing speed comments are spot on from what I saw, she was covering an absolutely enormous amount of airspace with the MW54 flat out most of the time. How much is the kit by the way ?

Stingray Construction
 

Hey Rob, :)

There's a few opinions floating around about the landing performance of this kit. I've heard it can be troublesome to slow down, but it sounds like it can be done without the use of an underside speedbrake. I can't say how hard it is till I try it of coarse. The lighter its built' the easier it should be to slow down though.

Mine is about 13lb with the UAT full and the tanks empty. There's about 75oz of usable fuel capacity. I don't think I could have built it much lighter because this is the first airplane I've ever built that required absolutely no balancing. I put it on the CG rig and it was bang-on to my amazement! :D I had planned the hardware layout to make it close but I didn't expect it to be THAT close!

Your comments about the speed add justification to the warning in the user's manual about flying at full throttle for prolonged periods of time. I wonder how fast Matt's will go with a P-70 pushing it??? :D Once I feel comfortable with the J600, I'll try it out with my J600-R test engine @ 14.5lb and see how it goes...

Kelly

Stingray performance.
 

Hi Kelly, my only experience of this aircraft is the one 10min blistering flight I witnessed. At 12lbs thrust is was way faster than anything I have seen in a long while. At no time during that flight did I see anything which looked at all difficult to manage in the way of stick twiddling skills. Only thng it might test is your eyesight if using higher power levels. Basically it seems to fly like a Roo does with (true) 10Kg thrust. It landed fine using the standard top mounted speed brake. I think you need to set it up in landing config. early in the landing circuit i.e. gear down, brake deployed, trimmed level. Allowing the speed to bleed off well before the threshold and adjusting descent or ascent using the throttle.This may require 30%-50% or more throttle with the nose high and on the back end of the drag curve. Always remember this type cannot be stalled and will fly much slower than you would expect. I think a JC70 would be wasted power and certain airframe destruction if that power is used.Hope that helps.

Stingray Construction
 

Yup, I'm not expecting it to land much differently than my Hotspot, if anything a little slower because of the lighter wing loading.

One last note while its on my mind. To any of you stingray owners that are building the kit with Robart Struts in the yellow gear, don't use an offset Robostrut (651, 652, etc.) in the nose. I think the reason Yellow did it with a twin nose wheel is that the 650 can be cut short enough to fit, whereas the offset struts have the telescoping mechanism further up in the leg. I don't know if this applies to BV's struts but you should probably check first...

Kelly

PS: I have an extra brand new 652L Robostrut if anyone out there needs one... :)

Stingray Construction
 

Well guys, I finally took her out again for its second flight and my first solo turbine flight. Everything went great!!!!!! the takeoff and flight was very easy. I set it up for an eight minute flight and let her rip. Once I had the plane trimmed out and cruising around half power to get comfortable with it again, I deployed the speedbrake a little at a time to get used to it. I lowered the gear and flew around dirty for a few minutes and gradully brought it back a couple of clicks of throttle after every lap around the field until time was up and lined her up on final. Touch down was soft until it started to bunny hop down the runway jumping higher and higher each hop until it final smacked down and stayed down, all the damage that occured was a scraped wingtip. What a sweet flying plane this is, I felt totally comfortable with it, well as much as a first solo could be that is! I think the bunny hops were from a slightly hot approach but I will work on that. Thanks to Brett and the other spectators for holding me up for the flight and helping out when needed. Another thanks goes out to Dean Wichmann for all his advise and tips through out the project, could not have done it without you.

Chris

Stingray Construction
 

Way to go Chris!

Did you make any changes to your original setup, more elevator, less aileron, changed CG, etc???

I think I asked this before, any chance you'll have yours at Whidbey or Princeton in September? Mine will be at both shows. I'm going to work on mine a little tomorrow and take it out on Sunday for the 2nd flight, and hopefully more...

Later,
Kelly W

Stingray Construction
 

Thanks Kelly, I am so stoked! I have waited a very long time for this moment I set mine up pretty much like glorfindels(sorry if I butchered the name) I kept the rudders at the books settings, most of my setup changes were setting up the fail safe. Found it to be very responsive in pitch and roll, will save yaw for another day. My CG is at 1/8th forward of the book but my header is empty, it is only 2 0z and is just ahead of the speedbrake servo. Mine came in on the heavy side at 14 lbs empty(I think my daughter snuck a cinder block in there when I was not looking), but it flies so nice. I think that I can bring it in much slower, I made a rather flat approach with maybe a touch of power, but I think it was residual thrust pushing her along. Next flight I am going to try to use my lower speedbrake to trim the plane level after the top one is deployed and then mix them so I don't have to fumble on the trims when I get ready to land. I also plan on trying to get her up high and slow her up to see what happens so I know how much more I can slow it down. This is going to be a great bird to learn on. Will not be able to make it to any more jet events this year, DAMN!

Chris

Stingray Construction
 

Yup I was out out there watching Chris on this flight.

Poor guy was so nervous, not that I could blame him. :)

That was my first time seeing a turbine ... pretty impressive. So was Chris's flying.

Allan

FLutter
 

Can someone tell me, i read that shrouded aileron hinges help prevent flutter. Is this correct or am I imagining it??

Some photos as promised.

Stingray Construction
 

And another.

Re: FLutter
 

That's correct.. they do, but all they're really doing is effectively sealing the hingeline, which is the real help. Nothing prevents flutter though like a non-flexible, slop-free linkage.

RE: Re: FLutter
 

wow alot of good info i was woundering for the air brakes on the bottom couldn't you just mount the gear doors on the struts like on the bob cat to slow it down????