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@@gustavoenriquejimenez8098 they do!! Even with a trailing edge spoiler (inverted gurney flap?) it puts up enough lift to fly.

Thanks! First I took a regular vaporizer and filled the little tank with mineral oil. Then I attached a silicone tube (RC fuel tubing dubro part# DUB897) from the output to the copper tree I soldered from tube (K&S 1/8" tube leading to 1/16" tubes I think) then you need to pump the smoke out so I attached an air compressor to the air intakes on the vaporizer. The trick is to have a fully charged battery in the vaporizer so that it lets out a steady dense stream of vapor, and to set the air compressor very low in pressure so the 'fog' comes out at the same speed as the air flow or else it goes turbulent if it comes out too fast. Depending on the test I first set the air speed and then set the fog air flow rate to match before recording a test. Some examples like the X-37b show both high speed and low speed flows which are quite different. In theory one could use a smoke machine that is pumped in by the exhaust fan of the whole tunnel, therefor producing proportional smoke speed, or a venturi of some kind. but since I have a shop compressor and don't mind tinkering a bit this was the method I went with.

@@chrismofer thank you for such detailed explanation! But what do u mean by a regular vapoorizer? Is it thermal or ultrasonic?

@@DigitalFAB it's thermal, the kind with a wick and heating coil. They are sold at vape shops. But for any kids that want to build this, you can make a Halloween smoke machine or dry ice in a box work too.

@@chrismofer thank you!

Do you know the model vape you used? Would be super helpful

we are currently re-covering the wing after installing some mods like a payload release and onboard glow. Monokote it shall be 👍

indeed, laser cut kits plus CA glues make building a breeze compared to die crushed or printwood kits, white glue & T-pins. I build is by holding parts like the ribs in place over the plans and tacking them in place with dots of CA glue, then you can lift the skeleton off the plans and add more significant glue gussets to affix the parts together. This way builds fast and (mostly) keeps from sticking to the plans.

@@darrellcook8253 we took the opportunity to strip the wings to re-cover them. In the meantime we added a payload release in the left wing as well as an internal fuel fill pump, and will also soon add an onboard glow driver before we button it up with brand new monokote or ultracote. All in, we added just a bit of weight but that will enable many future shenanigans. The frame is still in great shape thankfully.

I wonder how much you could shave off and still be able to fly. And I'm sure having the bottom covering on helped.

Excellent. Thank you for pointing it out. A lesson learned for sure

Great question, It is not a functional pitot probe but it is there on the real Space Shuttle 'Enterprise', which was the shuttle that did atmospheric drop and landing tests but never went to space. It also has the aerodynamic shell covering the engine bells (in order to not completely spoil the effectiveness of the carry aircraft's rudder). I really put the wire there because my shuttle model actually flies when launched with a rubber band, but is a bit tail heavy without the tip probe on there. On experimental aircraft they often put the airspeed pitot tube out on a mast in front of the aircraft in order to be sensing clean undisturbed air. those readings can be used to correct the data from inboard mounted sensors on the final space-going orbiters.

The way I measure the flow of air is with a regular windspeed meter, which is basically a handheld fan with a tach on it. I place it in the test section with the model, seal it up, get a reading, then remove it for the test. The airspeed can also be precisely measured by knowing the dimensions of the test section and counting the video frames the smoke wisps take to cross it. The density (static pressure) of the air is inferred by knowing my altitude and the temperature. With a pocket digital weight scale placed under or behind the model I can measure the force of lift and drag. With that data and measurements of the size of the model one can work out the Reynolds number and coefficients of lift and drag which is what you need to apply the findings to full scale aircraft.

@@depass9843 factually correct

Probably a 300mAh or 280mAh 2s. It is the same type of battery used by the 2-cell UMX airplanes from Horizon.

the kit comes with red tissue and decals, I used light coat of spray clear cote TS-13 to seal the tissue rather than 'dope' like the old days. The cowl comes white and was made aluminum color with TS-17 gloss aluminum paint.

I set the battery in the pilots seat or just behind the firewall, it sort of jams up front.

In this case I took the electronics from a UMX Pitts, which is about the size of the DR-1 kit. Many UMX props fit the same adapter. I use a smaller prop with more pitch for speed and a larger prop with less pitch for 3D or slow flight. I think this prop came from the UMX Yak 54 180 3D. I also sanded the corners of the prop to round them a bit to look less modern.

It is an enjoyable build! others have had good luck as well with free-flights. If you RC convert it, remember to stage the electronics far forward because these models tend to be tail heavy once you add control surfaces horns and pushrods way back there.

@@chrismofer Thanks. Yeah I remember a Nieuport and a Camel that never flew right. I couldn’t bear adding lead to a plane :)

EFLUM180BLB, a 3000kv brushless motor. It is the motor from the original UMX Pitts S1S from Eflite. I took the main board, motor, and pushrods and control horns from the crashed UMX bird.