Originally Posted by zolpot

I still haven't started the build yet, just bought all the components.
Will be posting build pictures on it's thread.
I'm expecting more than 90 minutes.

The only thing I'm in doubt about this setup is the batteries, I'm concerned about the discharge rate, it's 60c constant, maybe it's not good for endurance.

Ok ;
I have a 4 s batterie 4000 mA and I can flight about 45 at quiet speed !

When do you plan to finish yours ?

As soon as all the parts arrive, the plane itself hasn't arrived yet, it takes about 20-30 days to arrive where I live, but should be here within a week.

Originally Posted by zolpot

As soon as all the parts arrive, the plane itself hasn't arrived yet, it takes about 20-30 days to arrive where I live, but should be here within a week.

Have a nice time building it and hope to see the maiden soon !

Originally Posted by toubab

Was long to do the video montage but now it is done !
Here it is

http://www.youtube.com/watch?v=MYhYj16d0kg

Advise and idea will be welcome !

Fabrice

Very nice. How well do those airbrakes slow the wing down? Seems to work, once again instilling turmoil in the minds of all those armchair aeronautical engineers who say airbrakes on wings are a bad thing. Well done! Beautiful paint job, beautiful landscape.
Oh, can we see more of those pretty legs please?

Originally Posted by xviper

Oh, can we see more of those pretty legs please?

I`m sorry to have to ask you that as well.
Oh, and very nice build, congratulations.

Originally Posted by zolpot

I`m sorry to have to ask you that as well.
Oh, and very nice build, congratulations.

Thanks ! it work very well even if I did not test them enought as it was my "let said my first light with the X8"

The aibreaks are about 185 mm long and they open about 22 mm !

Ho ! about the legs, I will tell it to my whife who support me in my hobby !

Originally Posted by zolpot

The only thing I'm in doubt about this setup is the batteries, I'm concerned about the discharge rate, it's 60c constant, maybe it's not good for endurance.

I'm quoting myself to anwser my own question which I found the awnser here
http://www.rcgroups.com/forums/showp...24&postcount=3

and here
http://www.rcgroups.com/forums/showp...55&postcount=2

So, concluding, it's just like the esc amp rating.
I'd be fine a with 20c pack, and it would be the same thing. 20c X 5Ah = 100a

Very nice video Fabrice. And what a flying field...!!

One thing I would like to ask you good people: This is my first airplane with a folding prop. How loose should they be fastened to the spinner ?

Folding props generally are held on by bolts and locknuts. Even loose, they should hold, however, I put mine on just to the point that the prop can still fold by gravity when the plane is held nose up.
PS. Use a prop stopper so the blades don't fold too far and cross the mid-line. This has taken out more than a couple of motors off their mounts. (Ask me how I know. )

Thanks, the X8 slided in between Aluminium tongues. And yes it disassembles and is put into a bag for easy transportation.

Carl.

Originally Posted by toubab

Very good job ! I may said perfect !
Dont worry I am sure it will work well !

How do you hold the plane ?
Is it easy to carry in the car or in a bag ?

Let me know if you want to sail one one of this catapult because I will be very interestede

Thanks mate. I'm sure yours will do the job, well done!

Yeah, looks like we will need 25-35kg pull eh, 6 loops sounds about right. I just hope you don't have too much friction in your system... Cheers, Carl.

Originally Posted by Imagecatcher

Beautifully designed and made DT. makes mine look like scrap metal.
What is your kg pull? and the AUW of the X8?
Mine will be shy of 5kg so that + the cradle I figure I need close to 35kg of pull on the bands (6 loops @ 1m perimeter)
Again very nice engineering...your power toys are way better than mine.

Good evening from Finland!
I was pointed to this thread by somebody at DIY Drones in the X8-group.
I have spent the last almost 3 days reading this thread from the beginning on and I am pretty impressed but still have a bunch of questions.
For explanation: I do have some decent aviation knowledge and experience in IT fields and the defense industry but I have no R/C experience whatsoever. Originally, I wanted to build a multi-rotor AUAV but the design alone seemed impossible without the basic knowledge. Then I stumbled over the X8 at YouTube and was pretty impressed (how can't you be?).
I'm almost ready to order one now but I am still very unsure about a few things, the first being the drive. In this thread, people use everything from 3S to 6S and even systems with >1kW of power. What do I really need? I don't want to go insanely fast, I don't want to do aerobatics. My focus is on endurance and autonomous flight. My X8 would be mostly cruising and taking video or loitering and transmitting video and I'd prefer if it could do this pretty long. If it would be relatively silent, that would be a plus. So what would be the ideal drive for me?
My second point would be lighting. I seem to cannot find anything about where to put the tail light in a flying wing. Plan is navlights r/g into the front wingtips, navstrobes white into the rear wingtips and red acls in the roof and in the belly. Any ideas on where to put the taillight? The reason why I want "proper" lighting is that especially in Summer, my area is buzzing with LSAs which are allowed to take off and land where they want, outside of cities, if the have the landowners permission and on practically all water bodies. And, let's say, they don't always fly especially careful...
I don't want one of those LSA pilots run my X8 over when it's minding it's own business circling over a forest or lake...
My last point for now would be retractable gear. I have seen all posts and all videos on that in this thread but I have not found yet good closeups of the mounting. Again, I have no R/C experience whatsoever and that means I have no experience modifying R/C airframes. Thus, I am looking for good examples to mimic .

T:Stefan

6S is not typical
For 3S figure a 1000-1200Kv 30 series motor capable of a peak around 65A turning a 12x7, 12x8 to 13x7 prop.
For 4S scale by 3/4 so.. 750-900Kv 30 series motor with peak around 50A turning same props.
If using higher Kv can turn smaller prop.. and vise versa.
Give it an ESC capable of more than the motor's peak, as cooling is limited.
If balanced properly and without adding excessive weight or drag,
the X8 can cruise level at 100W. (About 8A on 3S or 6A on 4S).

Can't speak to lightning as I wouldn't want to try landing this plane in the dark.
I think retracts are a weighty and totally unnecessary complication.
Nobody has actually proven that they work (have only seen one X8 taking off and
landing on gear, and it wasn't with retracts).

ian

Originally Posted by deTonaTor_NZ

Thanks mate. I'm sure yours will do the job, well done!

Yeah, looks like we will need 25-35kg pull eh, 6 loops sounds about right. I just hope you don't have too much friction in your system... Cheers, Carl.

Regarding friction, I have used two linear bearings (CNC table bearings) so it slides quite well. The friction is mainly from the black polyeth block that acts as an anti roll guide. The bearings are mounted in a plastic race so that may wear too. My objective was to be light and avoid two runs of Ali But it may prove false economy.
Do you have adjustment in your bearings t clamp onto the rail as it wears?
looking forward to seeing your maiden TO
Troy

Originally Posted by Daemon

6S is not typical
For 3S figure a 1000-1200Kv 30 series motor capable of a peak around 65A turning a 12x7, 12x8 to 13x7 prop.
For 4S scale by 3/4 so.. 750-900Kv 30 series motor with peak around 50A turning same props.
If using higher Kv can turn smaller prop.. and vise versa.
Give it an ESC capable of more than the motor's peak, as cooling is limited.
If balanced properly and without adding excessive weight or drag,
the X8 can cruise level at 100W. (About 8A on 3S or 6A on 4S).

Can't speak to lightning as I wouldn't want to try landing this plane in the dark.
I think retracts are a weighty and totally unnecessary complication.
Nobody has actually proven that they work (have only seen one X8 taking off and
landing on gear, and it wasn't with retracts).

Thanks ian!
Regarding the lighting, I'm not planning to fly in absolute darkness - it's doesn't really get dark here in summer - which is part of the problem because if there is no total darkness, ("astronomical night" or something like that), the LSAs are allowed to fly but in reality there is some weird twilight in which you don't really see anything clearly and I fear, my X8 would be invisible to them without lights.
Take offs and landings should go either autonomously or via FPV cam.
At least for the autonomous T/O and landing, I'd need wheels and I was under the impression that a fixed gear produces substantial drag which would kinda counteract my priority of long endurance.
T:Stefan