It was with immense pride that I saw Red20RC mentioned in the Flite Test “Blunt Nose Versa Wing” episode. So it came as a bit of a shock when I decided to destroy the wing that started it all…
Why?
Let’s start by having a look at what I think was the final flight of the FPV Wing V2…
It was a great flight in less than perfect conditions but I had a few misgivings on reviewing the video.
- My center section was never the largest and squeezing even an 1800mah battery into the cramped bay was a chore.
- The GoPro mount wasn’t the best and the bottom of the camera was vulnerable on landings.
- I’d put my smaller 250mw FPV Tx in the wing with a basic cloverleaf antenna and it didn’t cope too well when we got higher and further out.
- Even with some colorful markings, it was difficult to tell which way was up!
- I kept breaking the vertical stabilsers off.
- There seemed to be a lot of instability in yaw. At times in the raw video footage the side-to-side wobble was quite pronounced.
So I decided that it was time to give the FliteTest Blunt Nose Versa Wing a go – with a few modifications of course.
Originally, I was going to just take the FPV gear out of my old wing but a couple of slashes with the box cutter and it was all over for the FPV Wing V2.
Blunt Nose Versa Wing
I’m not going to go into too many details about the build. The FT article and video are great and it really is only a Versa Wing with an extra bit in the middle.
I stuck to the plans pretty strictly for once, even keeping the tabs in the right places to see how it all worked. The new center section is a work of art. The FT guys have once again really thought this through and taken my, and other builder’s ideas and improved on them to the point of perfection.
I really liked the layout of the bays and the slightly larger area gave me enough room to fit my newly purchased 3600mah 3-cells in.
I did try to keep it neat by using my steel punches to keep the slots rounded and cutting access holes for the servos and other electronics. The build went quick, even with me trying to take my time!
Modifications
In the end the build was so good that apart from some access holes the only change I made was to the vertical stabilisers.
I mentioned before that there was a definite wobble in the yaw axis especially at higher speeds. I think wings are always going to suffer from this to a certain extent as they just don’t have that nice long tail moment arm that produces a “weather vane” effect to keep them tracking nicely. On a wing therefore you are trying to achieve the same sort of effect as a skeg on a sailboat or surfboard. My feeling is that on previous wings the stabs are just too small to produce the desired effect so I decided to extend them upwards and see what happened. This modification would also serve a dual purpose as it will be easier to orientate the model if the stabs are not symmetrical.
The new vertical stabilisers are pure guesswork and to be honest they now look a little large! Time will tell…
Finishing Up
I used foam board from different suppliers on the wing panels and center section. It came as a bit of a surprise then that the foam in the center was noticeably thicker than that in the panels. This isn’t a major deal (and better that way around to be honest) but it did make joining the three major components a bit more of a hassle than it should have been.
The extra space in the center bays made getting all the gear in a doddle. My new Taranis Rx and ImmersionRC 600mw FPV Tx went out in the wings with the ESC in the center to keep everything apart.
Power this time comes from a Turnigy Park 450 motor turning a 10 inch folding prop. This in combination with the 3600mah 3-cell lipo is putting out around 350W at full throttle. Assuming (hopefully) that cruise is at around half throttle the draw is only 10A so that should give me a good 30 minutes before I need to come down.
Following the FT build I put a plate under the camera and battery bay to strengthen the fixing points. I hate cutting ply at the best of times so I found that 3mm Correx plastic was an adequate replacement.
Balance is always an issue with wings but I reckoned that the new larger battery would help there. It came as a surprise then that it was still tail heavy and needed a little lead in the nose even with the battery wedged right up behind the GoPro. There is definitely an argument here for using a board camera next to the GoPro.
Let’s get straight to the video then!
So what do I think?
To be brutally honest, this is probably THE most PERFECT airframe I have ever flown – especially for FPV. The blunt nose versa wing is an awesome design. It is a nice manageable size but big enough to be stable and easy to fly.
It had a great range of speed with an excellent glide ratio. Turns were nice and smooth and, whether it was the oversized vertical stabilisers or not, there was no instability in yaw.
I seem to have stumbled upon the perfect power setup for this model with the Park 450, 10×4 folding prop and 3600mah. There was more than enough power for vertical performance but after 20 minutes of relaxed FPV cruising I had only taken 1400mah out of the battery. This is a fantastic result and makes 45 minute flights a reality for the future.
Conclusion
I’m actually glad I destroyed the V2 Wing now. I’m also glad the Flite Test chaps took my and others work and created the Blunt Nose Versa Wing.
If you are looking for a mid-size flying wing for starting out in FPV or long range cruising with the goggles on then you could do a lot worse than downloading the plans, getting yourself some foam board and start cutting…
What next for me then?
Well, there’s plenty more FPV to be flown. I want to experiment with some OpenLRS gear and I still have to find something to put an APM in and try some automated flights. I’m even thinking of moving 2 2200mah batteries out into the wings for even greater airtime.
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My motor is the Park 450 1200kv. I should say however that with the combo of 3 cells and the 10x4 folding prop it is over-propped and is drawing too many amps at full throttle.
I would probably look in the future at the lower Kv motor to bring the amps down at the cost of a bit of thrust (which I don't need anyway).
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What brand and source for the 10x4 folding prop and hub?
What kv is the Park 450---890, 1050 or 1200 kv?
Finally, is the battery a Turnigy 3600mAh 3S 30C Lipo?
Cheers, JC
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- The prop is the most basic one they had and is a 10x8, not a 10x4 like I keep telling people! (http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=13144)
- The motor is the Park 450 1200kv (http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=19036)
- The battery is a Turnigy 3600mah 30C (http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14646)
Now, the problem with my awesome setup is that 10x8 prop is too much for the Park 450 and the amps at full throttle are too much for the motor really (around 28A static). If it was the 10x4 then things would probably be better. As a result I am having to clip the throttle to ensure I don't burn things out.
Hope this helps.
Mike
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The V2 wing had a 2200kv motor in it and it did go well. Many years ago I had a Zagi that I electrified with a 4000kv motor - that thing went like a rocket!
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I currently have the power setup mout of a crashed radian do you think that that would work?
Thanks
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To be honest this is a little on the large size for a Versa although the blunt nose versa could probably handle it.
I would match that up with the same 10x8 folding prop I am using and it will have bags of power and cruise on a very low throttle setting.
The only down side will be the 480 is pretty heavy and you will need a lot of weight up front to balance it out.
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also what range can i expect from the teleporter 3
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With FPV setups I am nowhere near an expert! With range it is always a case of money + technology = range & quality. The Teleporter comes with the FatShark 250mw transmitter which will be the same one that came with my Attitude SD set. With the basic whip antenna you won't get much range at all and the picture will skip and flicker all over the place - maybe 400 to 500 meters tops.
Your first upgrade in FPV should always be some cloverleaf or Spironet antennas. I use both and don't have a problem with either. I used a 250mw setup with a cloverleaf on the Tx and Spironet on the Goggles with the V2 wing and even then the picture was breaking up whilst we were still in line of sight.
This wing has the ImmersionRC 600mw Tx and Spironets all round. This time the picture was solid throughout the maiden flight. The only interference I got at all was when I flew directly overhead.
Then of course you have to look at environment. We have big powerlines nearby so they may cause interference. Are you going to fly low into trees, valleys, behind mountains etc? All this plays a part.
Of course, when you become really hooked then you can start thinking about ground stations, external receivers, diversity setups, antenna trackers - the list goes on!
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Just thinking aloud but another idea I saw on a blunt nose versa from way back (long before mine) was if you have 2 batteries of the same size (e.g. x2 1800mah) then put them into the leading edges of the wing either side of the center section.
This way you get the equivalent of the larger battery and you can also get your other gear way forward in the nose to balance it out.
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Not really though. I have a 480 and used it in a previous project. Bags of power but I reckon way too heavy for the BNVersa. You'd end up putting so much weight in the nose just to balance it out.
I would still use the 450 but either one with a lower KV so I could still swing the 10x8 folding prop or go smaller on the prop. Maybe a 10x4 or 10x6 would be okay. Maybe even a 9x6.
What I did in the end was set the "travel" on the Taranis so I can only use a max of 80% throttle. That way I can be sure I never try to force it too hard.
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That's probably a bad thing to say but what I really wanted in this airframe was a cruiser so a bigger prop with a smaller pitch makes sense to me.
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People who don't ask questions are the ones I see daily on Twitter crashing their RTF DJI Phantoms into buildings, trees, cars, people etc and giving us all a bad name 😤
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I do like the "bunny ear" stabilizers but I found them to have pros and cons. On the plus side they do reduce the yaw "waggle" you get on wings and notice on flight footage. On the downside they do make the wing more susceptible to crosswinds.
I actually dismantled this wing recently to use the gear in something else and now I am sad that I did. I'm going to put another one together really soon as they are just too good.
With the balance, they have a fairly small sweep compared to other wings (around 30 degrees compared to 35-37 on some wings) so the balance point is quite far forward. As a result you need a lot of weight in the nose. I had a 4000mah 3S in mine and a GoPro and I think I still needed weight to balance it out.
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I am using a 2200Mah and no fpv so no wonder it takes allot of weight. Busy melting some lead to weigh down the nose. On the other hand I used a bluntnose wing CG calculator and my CG is about a cm behind the point where the plans show them.
I will try this point and find that if the plane proves to be tail heavy I will revert back to the plans.
Thanks for your reply.
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The BN Versa does suffer from being tail heavy. The problem I think comes from the fact it has only got a 30 degree sweep, whereas a lot of wings tend to be in the 32-37 degree range.
I found that the only way I could balance it was with plenty of battery and a GoPro in the nose. Even then I think I needed some extra weight.
In my latest versions I've CNC cut a mounting box for the FPV cam and GoPro in G10. The protection is worthwhile and the added weight of the G10 helps to balance it out!
Cheers,
Mike
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Have a look at http://red20rc.org/katana-x-kfm6-fpv-wing/ for more info.
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