Tuggs

I finished the installation of the main gear doors yesterday. As you can see I decided to use a servo to open and close the doors. The installation wasn't very challenging. The servo arm is kneeled once the door is closed which means that G-forces won't pull the door open during flight. At least according to my plans! Manual tests were successful! With the long servo arm, only little movement is necessary to open the door and of course, there is enough clearance for the wheels to extend and retract. I am going to repeat the procedure for the other wing tonight and then move on to the nosegear and strut covers.

Tuggs

Waiting for the pipe pretty much prevents me from installing the turbine which would be up next on the list. I also have a shorter front oleo on order to move the landing gear to the scale position. Meanwhile I did the preliminary installation layout of ECU, Batteries, Power supply etc ... Also started on the wiring in the fuselage but once I have the length of all cables,I am going to use a long tube to lay the servo wires through the fuselage.

I might not be able to post new progress until Monday.

Have a good weekend, readers!

Tuggs

Small update but without new building pics I am afraid. Turbine is here and the pipe will arrive Saturday!So far, I already made some drawings for the turbine mount conversion. Tonight Iam going to finish the wiring inside the fuselage and get the electrical components mounted in the nose section. I am also waiting for the new nose strut which will hopefully arrive this week.

Apart from that, not much happened due to beautiful flying weather

Tuggs

Just in case anyone wondered why there hasn't been an update lately. I just returned from vacation and I sill haven't received my thrust pipe Apparently it will arrive within the week so I can hopefully install the turbine during the weekend. Apart from that all soldering and wiring for the servo's is done. We're coming closer to get the scorpion ready for paint-job.

Meanwhile I am once again unsure about the paint scheme ... I am still favoring the yellow /black 437th FISscheme but Iam also thinking about a fantasy south-east asia camouflage (olive/dark-green/brown) paint... I think it would just look awesome on the Scorpion..... Anyways I have a couple of more days to finally decide

Tuggs

I finally! received my pipe from Turbo-Didi this week. I have to say it was worth the wait. Quality is top notch. As mentioned before I'll use a Behotec JB180 Gold for power. I am going to check back with Air-C-Race to have some formers for the Pipe and turbine mount made, as the kit version is layed out for two turbines only. Since Air-C-Race can CNC such stuff, this will be a lot easier than any homemade construction.

Tuggs

Meanwhile i started on the paint-job. For the colors I use Tailormade's DeBeer base coat and paint-masks from Callie-Graphics. I have to say her service is just awesome. It took only a couple of days from ordering until I had the paint masks and stickers delivered to my doorstep here in germany.

For fuselage and wings I used black to shade the panel lines and next I applied some layers of chrome / silver. I tried to simulate washed out and irregular coloring for the aluminium panels by changing the mixture of the chrome silver with thinner. I like the effect and I think it came out quite nicely. Up next was a thin layer of mattened clear coat. I also started to chip off some of the paint to add some weathering effects.

Tuggs

To keep up the motivation I couldn't resist to apply some of the paint mask and stickers to the plane.I know that this is not how you do it but who cares The plane is pretty much done except the turbine, pipe and nose retract. My hopes are up the plane will lift off for maiden within the next 10 days... It is still a major delay to my original schedule but I am still positive to have the plane ready for jetpower.

dm5883

Please keep the thread going. I love this airplane!!

dirkcim

, it will look more nice than me scorpion

I am looking forward to fly with you together at the JP

Mark H

I now have several flights on my F89 Scorpion, I am very happy with it, I am using a single Jetcat P180 rx in one side on one pipe , total weight of model came out at 18kg with ballast in nose, I am using a single tank in the other duct with 3.7 L of fuel giving flights in excess of 7 mins, all the gear works well , congratulations to Air racer on a great kit , I am also using Powerbox-systems srs champion and 5000mah opti power lipos for power and also useable weight in the nose. Paint and finish is from Ralle at Taylor made decals , .

Tuggs

Great looking aircraft, Mark! Congratulations

Racerbuilder

UH...

looks so nice... cant wait to see all 3 together in the air.....

See you all at JP

schroedm

My Feedback: (1)

Nice Mark! Pretty unusual subject so good to see something different on the scene!!

Was that the one I saw for sale in Germany?? I was tempted.

Mark H

Hello Mark.
No a new build , from a kit , goes together real nice and so easy to finish as the mouldings are so clean, would like more rivets but as you know on a 1/6 th scale models only fasteners realy show up as paint on real aircraft would cover rivets.. But flying makes up for that.
Regards

Tuggs

In case anyone wondered about the lack of updates - here is a short one. The scorpion is now officially ARF.

I used some 8mm plywood to build my own turbine mount and finally installed the fuel tank, pipe and turbine into the airplane, which was the last big milestone before the final assembly of the electronics, which will happen this week. I also applied the last decals and paint to the plane and finished with the last layer of clear coat druing last weekend. Pictures of the first rollout should be available by the end of the week. I am putting the last bits and pieces together and since we will have some more summer days ahead of us i am hoping to clock the first testflight on saturday or sunday.

The picture shows the turbine mount. The mound is made out of 4 pieces (of which 2 are not shown on the pic, sorry). 2 rails are hysol'ed on the original mount for the twin turbines and then bolted to the turbine clamps and the mounts you see on the picture. A one piece mount was unpractical since I would not have been able to remove the fuel tank and pipe. Even though the fuselage is huge, there is not much space to manouever those bigger parts inside.

dm5883

Thanks for the update. Keep'em coming.

Tuggs

Okay, I've been a bit lazy updating the build, so here are some pics of last weeks progress shortly before the build was finished. The F89 is ready for its maiden flight which was planned for today. However it didnt work out due to high crosswind at our flying field. Hope it gets better tomorrow evening. There is still enough light until 7 pm so I should be good heading out to the field after work.

Alright, the final bits and pieces came together real nice. Took me a while to figure out the programming of the Pro-jet sequencer but once thats sorted its a real joy to work with. One little thing to worry is the distance between the pipe and the fuel tank whichs is only few centimeters. I added some 2mm balsa and alloy tape to insulate the bottom of the tank. Short test runs on the ground were ok. Fuselage and the inside of the plane remained somewhat hand-warm. I ordered the pipe completely dual walled but as you can see on the previous pics it is not. To my luck because the pipe wouldn't have enough space below the tank. Anyways, enough of that.

Tuggs

I also managed to get the finish "almost" complete last week. I still need to add the black stripes to the tip-tanks which I sucessfully shuffled around until now. I am also going to add some weathering with oil pastels. After that I'll apply the last layer of clear coat. Of course this will only happen if the plane does not fit into a large plastic bag after tomorrow.

Some pics of the 99% finished plane. Please excuse the messy install in the elctronic compartment - I am not the cleantest guy when it comes to that. However it all works well and the nose former can be dismounted in a couple of minutes and without having to disconnect too many wires and tubes. I pretty much used up all the space on the board on top and bottom. What you do not see on the pics (since they're a bit outdated) is the lead i needed to balance the plane properly. Doesn't really amuse me to carry almost 3lbs of ballast around, but still I managed to get below 40lbs which is quite good for a plane of that size.

On a sidenote I'd like to mention that I will switch to a behotec electric landing gear shortly. I recently started to convert most of my planes to electric retracts and the scorpion will be next.

Tuggs

My next update will hopefully be the succesful flight report. All the compulsory taks are done and the only things left to do are the cockpit and some detailing on the inside of the gear doors. I'll also have some scale details such as the windscreen wipers, pivot tubes etc. waiting to be added to bring the plane alive.

Although the scheme is not 100% scale I really like it and I am sure it'll look awesome in the air.

husafreak

My Feedback: (3)

Just great! Glad you did the 437Th scheme. And I hope the maiden is just one of hundreds of great flights!

Tuggs

Hello Everyone!

The F89 had its maiden flight during sunset last Friday. It flies beautifully. There is some debugging left to do, such as the canopy interlocking since the built-in magnets are too small to handle the fuselage pressure as the canopy flew off shortly after takeoff. The behotec 180 handles the plane very well and there is lots of power reserve. The sound with the bifurcated pipe is just awesome.I'll post better pictures and a video once i receive it. For now I can only share a small screencap, but better than nothing.

dm5883

Great Job!!!!! The first of many, many flights I'm sure. Please keep us updated as you work out the bugs.

husafreak

My Feedback: (3)

Hey Tuggs, what is the status of your F-89 and can you tell us more about its flying qualities?

Tuggs

Hello Husafreak,

Yes, its been quiet around the Scorpion during the winter. However, I have her on the workbench since last week to do some slight modifications. I need to change the canopy locking and I am also lowering the gear to a scale position. I am also adding new fuel tanks in front of the CG as I had to add almost 2,5kg of lead to the nose in order to balance the plane properly.

I'll post pictures along the way and I am sure she will be back in the air in 2-3 weeks. Of course with more pics and videos

Thanks for you interest in the plane.

Regards

T

dirkcim

Hi Husafreak,
I have a couple of videos where you can see the characteristics in the air.
The last one is a demonstration of an Cortex under strong wind conditions.

https://www.youtube.com/watch?v=VNSL7ad_Pzw https://www.youtube.com/watch?v=JB6WBwky7IM https://www.youtube.com/watch?v=9TrSR937MuM https://www.youtube.com/watch?v=LpbmdS-YSN0