*Unofficial* FT Spear

[Kerberus]

Although I don't have access to the wing at the moment, I recall it should be somewhere between 900 g and 1 kg. How does your configuration perform? Do you feel like you have sufficient thrust? You are spinning a similar propeller at a higher kV at a possibly a wing-loading, so I think I'm running short in power here. BTW yours flies great, where is this filmed? Looks like the Balkans.

 

[NorbertK]

Thanks for your support, yes, she's flying ok- ish, a little underpowered, I don't have unlimited vertical. It is my first ever build, never builded an aircraft before. Mainly goal was to be able to fly it slow And yes, it is Romania, Transilvania, Cluj, just 5 minutes outside of city limits.

 

[kulens]

Result of the paint-job:

 

[NorbertK]

Brain fart, I have a 11x5.5, not 10x5.5 prop.

 

[NorbertK]

@kulens, great ! paintjob ! Go fly !

 

[Francorf]

Hey Guys and Gals, new here. I have been looking all over on how to troubleshoot my problem with launching the Spear. I have my CG at what was recommended but for the life of me I cannot get the plane up in the air. As soon as i launch it goes into an immediate nose dive.
I have my prop set to CW( the way that tightens the nut) with a reverse 9x4.5 prop. Has anyone else had this issue? I must have tried launching at different throttle speeds, aileron configs at least 10-15x's i dont know how many more nose dives this plane can take. I think after repairing my nose damage I will try to place some weights of some sort in the rear compartments by the prop...

Any thoughts or help will be MUCH appreciated.

 

[NorbertK]

Fully equipped, she must glide well, without motor power.
First time I grabbed she from the back, with the motor between my fingers and throw her horizontally. She must flying ok, no nose down. Then the CoG is right.

 

[NorbertK]

Try move the battery back to the rear of compartment. My elevon reflex is almost none, like 3- 4 degree up, a bit of nose heavy, from 50 to 100% throttle she flights level.

 

[NorbertK]

Like this :

 

[Francorf]

Try move the battery back to the rear of compartment. My elevon reflex is almost none, like 3- 4 degree up, a bit of nose heavy, from 50 to 100% throttle she flights level.

Thanks for the feed back, I will try it out and let you know how it goes.

 

[NorbertK]

Minutes of onboard vid:

 

[kulens]

I like to share some pictures of the maiden flight. All went well, but I'm afraid it'll be a build that I will not fly often. It is just too noisy! I might fly it from time to time, but the noise-level is way to high; sooner or later, people will start complaining.

Having this experience, I prefer my versa-wing with tractor-style. It's more agile in flight and as silence that people nearly have noticed it in the air.

 

[Kerberus]

@NorbertK Man, I'm so jealous of your flights, can't wait to set up the wing so that I can finally fly it.
@kulens It is not a surprise that the wing is loud, it is caused by the interaction between the disturbed flow exiting the fuselage which impinges the propeller, thus causing an uneven loading of the blades. This will happen with all pusher configurations. In fact, the advantages tractor configurations are way better other than the fact that propeller will be in the field of view of the camera. In any case, you have made beautiful pictures, I guess you had somebody else with a DSLR and a telelens? BTW what is your motor setup?

 

[NorbertK]

Yes indeed, great pictures. Yes again, pusher is loud. Managed to reduce the prop sound cutting the back of fuse more aerodynamic ( less hight ) in front of the prop, big difference !

 

[kulens]

Managed to reduce the prop sound cutting the back of fuse more aerodynamic ( less hight ) in front of the prop, big difference !

Thanks for this tip! I might have a look to change the shape as well at the back to streamline the air is a better way. As there is still space between the backside and the prop, I might use that space to add foam.

Did you experiment with different shapes and cuttings? I know that the feathers of owls have a special shape to brake the turbulence of the air into smaller vortexes. Owls need to fly as silent as possible to be unmarked while hunting.

shape of the feathers of an owl:


article: Owl Feathers Could Inspire Quieter Planes

 

[NorbertK]

@kulens
If you have space between prop and backside is good, bigger the space, better for sound reduction. But the backside, in the original design is too high, creating turbulence, there must you work a bit. I get my design from a wing named Ritewing Drak.

 

[Ibanous]

Just finished building my second FT Spear

Got hooked on RC just over a year ago, thanks in large part to FT. I've been building multirotors and in the past few months I've been trying to learn to build/fly fixed wing.

So far I've built and flew the Mini Arrow, Alpha, Spear, and Sparrow. I've also built a Mig but my flying skills (lack there of) need some improvement before I'll trust myself to try to maiden it.

For the Spear my first attempt went relatively well and I named my plane the Flying Watermelon. I flew this a handful of times before my inexperience got the best of me and I lost orientation, then control and nosed it in hard.




I've now rebuilt as the Bumblebee. This time I've added a FC and GPS running INav. I can't wait to maiden it and see how it flys.

 

[shoeman]

Awesome designs everyone! I've started gathering the materials to build mine. It will be my first scratch build. I've got the foam board area under control but what have you guys been doing for the insides?
Wondering if this power pack is a good option https://store.flitetest.com/power-pack-c-fixed-wing-large/#product-description? ... except its out of stock.
and getting these push rods. https://store.flitetest.com/push-rods-8-pack-16-5/#product-description.
I have a receiver and transmitter.

Anyone know of a more detailed guide for the electronics I'll need and some installation help? I've been searching and haven't found the help I need.

Thanks in advance for any comments!

 

[Ricci]

Hello,
Have anyone experience with the EMAX 2213 on the FT Spear?
I have one laying around and im searching for a plane that fits.

 

[Ricci]

Ok, after reading the Data of the 2213 i think it will not fit.