I got this new plane delivered on Friday. I'm going to be a while before I can actually start putting it together properly, but thought I would start a thread here and share some pics - as I'd quite like some opinions about gear/layout etc.
My main idea here was to get a plane that can stay up for a long time, and cover a lot of ground, so for me something sizable that could carry a good amount of lipo
First off, this is the PNF version from HobbyKing (which is the only version they sell) http://www.hobbyking.com/hobbyking/store/__64681__FX_79_Buffalo_FPV_Flying_Wing_EPO_Airplane_2000mm_PNF_UK_Warehouse_.html (http://www.hobbyking.com/hobbyking/store/__64681__FX_79_Buffalo_FPV_Flying_Wing_EPO_Airplane_2000mm_PNF_UK_Warehouse_.html) It's pretty expensive for what you get really, but hey it was a present, so I'm not complaining :)
It comes in a big square shaped box, so big a cat could easily perch on it
(http://farm4.staticflickr.com/3940/15579354041_4a515a4ea9_b.jpg)
When it gets put together (just a dry push fit) it looks like this
(http://farm4.staticflickr.com/3956/14961279974_fabb1dd47d_b.jpg)
If you want to know how that looks in scale to a person, here's a silly picture of me holding it
(http://farm6.staticflickr.com/5609/15554727821_718fe8a28e_b.jpg)
Here's a view from the top showing one idea for the layout
(http://farm4.staticflickr.com/3947/15582853092_477ddbd382_b.jpg)
On the little wooden platform I'd stick the flight controller (I'm thinking about the MFD AP right now) and so obviously route the GPS to the outside of the plane. As I need to be able to take the wings off for transport, I'd like to keep everything on the main fuse, so under the side flaps I'd put a Dragon Link (thanks Rich !) on one side and then route a dipole out to where the wing section joins, and on the other side route the VTX out (used here for display purposes only)
I wasn't sure what counts in separate terms simply the rx to the VTX, or where the dipole is to the VTX. Worst case scenario gives me about 20 inches, best case about 28 inches.
I'm showing the pic with a single 5000mah 3s lipo, but I'd intend to fly with 2 of these (although possibly not for the first throw)
The flight camera is a bit more of a dilemma, in the pic I have my Mobius as my flight/recording cam, but aside from having the route some foam out for it to fit properly, once that nose section is glued in, getting it in and out looks like a pain.
The alternative is mounting on the nose section itself. There's a wooden big to bolt onto the foam section in order to mount a GoPro, so I was thinking about putting the Mobius on a servo at around this point.
(http://farm6.staticflickr.com/5600/15558329676_129aea2093_b.jpg)
Angle seems quite crucial here though, I feel I'll need to be pointing down a bit, but would like to spin around a look behind myself... so not too down, and I don't want to effectively add a big air brake to it. Can anyone recommend a servo that will give me a 360 view, but has a stop point so won't just go continuously ?
Comes with a 12x3.8 prop, which I've heard size wise is ok, but advised swap that supplied one with an APC. The prop felt massive, but seems to shrink once I stuck it on the motor. I'm sure it'll grow again when it starts spinning and I have to chuck it without severing my hand.
(http://farm6.staticflickr.com/5597/15582855562_b354e2b407_b.jpg)
Once annoyance that I found is that one of the capacitive nuts on the fuse that the wing screws into is missing a thread, so one wing can't be secured right now - so waiting for HK to respond on that >:(
More when I have it
That`s a fair bit bigger than I thought it really was. The scale photo really put that into perspective there. A strange shaped compartment but plenty of room to get two 5800`s in there by the looks of things.
I like it, looks great Wayne :)
That things huge! But Im sure you hear that a lot :D
Quote from: Coyote on October 20, 2014, 03:47:10 PM
That`s a fair bit bigger than I thought it really was. The scale photo really put that into perspective there
maybe wayne is a dwarf like warwick davis lol
Looks good mate,
Look forward to the build
Out of interest, why 3s?
Quote from: Brucey on October 20, 2014, 08:14:40 PM
Out of interest, why 3s?
That's what the motor is rated for and I already have them. I was a bit concerned here, but a youtuber in Oz is flying this config and getting nice results
What sort of flight times are you expecting from this? It looks lovely and I wonder if it might lend itself to a couple of camera mounts with a video switcher rather than a 360 pan. It actually might make more sense to have a cam facing backawards and one facing forwards, the forward facing one on a 180 degree pan for example.
Quote from: krikey on October 20, 2014, 08:37:36 PM
What sort of flight times are you expecting from this? It looks lovely and I wonder if it might lend itself to a couple of camera mounts with a video switcher rather than a 360 pan. It actually might make more sense to have a cam facing backawards and one facing forwards, the forward facing one on a 180 degree pan for example.
Between 40 mins - 1 hour. Should have room for that, but I want to keep things off the main removable canopy if I can for simplicirty. It's not a particularly friendly shape for looking backwards, the canopy goes up towards the back and has a big ridge in it. Not sure how much I'd be able to see
Has your wife always made you stand on bubblewrap in the living room, or just since you repurposed her egg timer?
Quote from: iPeel on October 20, 2014, 09:07:45 PM
Has your wife always made you stand on bubblewrap in the living room, or just since you repurposed her egg timer?
Ran out of adult nappies, so we improvised with the bubble wrap just in case I had an accident :)
That was the literal "just unpacked" picture, with bubble wrap and other packaging around. It was my egg timer, I actual bought it specially. Although I spent her £2 on it
How about a couple of mobius with the lens extenders? he mobius could then sit inside the fuse. Theres a nice bit of foam like a small fin that runs towards the prop.
Quote from: iPeel on October 20, 2014, 09:07:45 PM
Has your wife always made you stand on bubblewrap in the living room, or just since you repurposed her egg timer?
Pmsl!
Quote from: krikey on October 20, 2014, 09:16:15 PM
How about a couple of mobius with the lens extenders? he mobius could then sit inside the fuse. Theres a nice bit of foam like a small fin that runs towards the prop.
Yeah good idea
I love that cat ;D
I'd looked at the FX79 about a year ago but it was only available overseas so I didn't bother. I hadn't realised it was now available from HK UK so thanks for the info. I think next plane will be either the Z3 or maybe this, but definateley has to be something that breaks down small-ish.
Anyway I've just been looking online for info and saw this guy had some good ideas for his FX79 build - may be of interest.
www.youtube.com/watch?v=mwoqSrLI4rU (http://www.youtube.com/watch?v=mwoqSrLI4rU#ws)
Regards
Mark
I'm ready to fly it... but I haven't yet because I'm too scared a need a few buddies to help me. I made a video detailing what I've done, and so I could rant about how crap HobbyKing was, but how good other people/companies were
WARNING: Video contains lengthy footage of my big fat face, and thus may be unsuitable for small children to watch
FX 79 Build: HobbyKing Bad, Zeta/MFD/Bignose/Forums good (http://www.youtube.com/watch?v=xU57rLSKlKo#ws)
Wow, that thing's huge!
I think a binbag's not going to cut it Wayne so I'll volunteer to push the wheelbarrow after the maiden if you want.
Neil.
I was and I am still tempted with Buffalo but I don't even get enough time to fly the stuff I have in stock now. If anything I have a kitten similar to that one with a list of crimes deserving launch into space in Buffalo. (biting my foot, destroying some of my FPV gear etc)
Anyway enjoy it and report back how it handles.
Looks great and really tidy
I'm sure you're a better pilot than me, but a few thoughts
Is the MFD facing backwards? The arrow on the top is pointing towards the motor in your video :s
A different buffalo build I saw had the little pouches covering the Rx and video Tx cable had a slot mechanism to them. A strip of credit card glued into the removeable bit and then a groove cut into the wing to slide them in. Seemed to work well.
Tape on the bottom of the fusealage to keep it clean and scratch free? Maybe a bit on the leading edge too?
I have never failed a launch by a proper javelins throw. I have failed lots by wing tip launching. And I always launch with full throttle. Why wouldn't you on a wing? I understand why not on the bixler style pushers. The maiden will be fine, get your mate to wear a glove. Maybe throw it slightly downhill to give yourself a bit more time. And a bit of wind to make landing slower :)
Program dual rates so you can easily switch down if it's too twitchy.
Looks like a very clean build to me. I would love one but I have too many other planes tbh!
I'm fairly new to MFD too but love the idea of auto launch with it. Will come in handy with that huge wing. You will be able to wing tip launch it yourself!
Quote from: Billy_boy_2010 on January 19, 2015, 09:59:40 PM
Is the MFD facing backwards? The arrow on the top is pointing towards the motor in your video :s
It is, the wiring worked better that way, in the setup you can tell it the orientation of the AP
Quote
Tape on the bottom of the fusealage to keep it clean and scratch free? Maybe a bit on the leading edge too?
Yep - I've done the underneath, I may do the leading edge as well.
Quote
I have never failed a launch by a proper javelins throw. I have failed lots by wing tip launching. And I always launch with full throttle. Why wouldn't you on a wing? I understand why not on the bixler style pushers. The maiden will be fine, get your mate to wear a glove. Maybe throw it slightly downhill to give yourself a bit more time. And a bit of wind to make landing slower :)
Program dual rates so you can easily switch down if it's too twitchy.
Looks like a very clean build to me. I would love one but I have too many other planes tbh!
I'm fairly new to MFD too but love the idea of auto launch with it. Will come in handy with that huge wing. You will be able to wing tip launch it yourself!
I've always tip launched my wings, but there's going to be too much weight in the fuse for this. Part of the reason for looking at the launch mode is so I can put the radio down and give it a decent throw with my right hand. But it's got a lot of wing area, so hopefully with a bit of head wind it won't be as scary as I'm thinking. I'll have some rates in. The flitetest boys seemed to think it flies best at 50% - I can use this as my default and be able to switch up to higher if I need it
That is a beast Wayne :) Really like it form, vtx position is brilliant ;)
Love it. I fancy getting a fx61 to start with. There is just something about wings i like.
Sounds like you have got it all covered :)
My 60" wing needs a launch mode for sure!
Yes get Richard to stand on a hill to launch first time, a good headwind will help too. Then a good hard throw about ten to fifteen degrees above horizontal, and plenty of throttle as soon as she's clear of his pinkies.
Hi Wayne
Any news, I saw from your last YT vid that you said it (FX79)was in bits :wtf:
I'm afraid the maiden took a turn for the worse Simon, the plane hit the deck and literally all came to pieces. Video just processing at the moment. I'm not sure what the problem was, so input is welcome in the diagnosis
So here's the crash video - please let me know what you think the issue was
FPV Crashing: FX-79 Buffalo maiden disaster (http://www.youtube.com/watch?v=zobnhtnzja0#ws)
Looked like a simple old stall to me :(
It had just enough to keep flying intially, but when you gave it some "up", that increased drag and because it was nose-heavy it simply went in.
I'm guessing that if you'd let it settle for maybe 10 metres more or so, and lost a metre or two of altitude, the airspeed would have been enough for it to recover.
Quote from: Steve W on January 28, 2015, 05:19:52 PM
Looked like a simple old tipstall to me :(
I thought it would roll on a tip stall Steve - hence the slight confusion ?
Quote from: CurryKitten on January 28, 2015, 05:21:05 PM
Quote from: Steve W on January 28, 2015, 05:19:52 PM
Looked like a simple old tipstall to me :(
I thought it would roll on a tip stall Steve - hence the slight confusion ?
Yea corrected it (and edited my post) ... I meant a stall, simply loss of lift. Both wings would have lost lift at the same time if you gave up elevator and were already on the edge - if it was balanced nicely then it would have just sunk.
I'm probably wrong though but that's what it looks like to me. No lift, nose heavy.... nose goes down .. blam :(
Control surfaces on the elevator reversed, you went to pull up when in fact you pug the wing in a dive
See, I'm assuming that the control surfaces were all working properly ........ Wayne? :D
looks like reversed servo to me its to co- ordinated not to be ???
CoG to far forward? Not enough throttle? To heavy for power unit?
Elevon throw reversed?
Motor reversed?
Prop on backwards?
That throw was to steep.
Should have walked up that hill, or used a bungee.
Did you have any wind in the nose, that would have helped to.
Might have been better to try it line of sight with just the battery ,motor and esc before weighing it down with FPV gear.
Could have been any of the above really, at least it's fixable.
Just my thoughts.
It does not look like a stall to me, to controlled. The FX79 also has a huge wing area and can fly very slowly, my FX61 still surprises me by how slow it can go. My vote is for some sort of control surface input, intentional or otherwise.
Sorry for your crash, its real setback when this sort of thing happens.....
rgds,
Marcus
I am guilty of having reversed my ailerons twice before, so I checked them on this one, and then got Neil to check them again for me... twice. Then we checked that stabalise would also react in the right way - it did, although it wasn't engaged during the short flight. In terms of my inputs, I hadn't pulled up, I'd just given a little bit of right (iirc) input to straighten out before it plunged downwards.
Wing area is very large, and was only taking a single 5000 3s, so I thought it would have a pretty good glide on it.
Prop was on correct way and motor was spinning correct way. Neil did note that it didn't seem to push against him that strongly when I put the throttle on. Unfamiliar with how this should feel with motor/prop combo. It's a 900kv on 3s running a 12x3.8 prop. Obviously we're not expecting it to fly out of the hand - how strong should it feel ?
When I get a chance I'll check the amp draw on the motor to see if I can figure it it's operating at it's full potential (yes I did calibrate the ESC)
CurryKitten are you sure you where in manual and it was not a AP input but to much that caused a stall :+
Very sorry to see this happen I had a similar thing happen with my Scout bee on her first throw but that turned out to be interference from my ESC.
I hope she can be repaired ok
dizzy
Oh no. I really enjoyed watching this build :(
i have never witnessed a proper wing stall before- but IMO it's too extreme to be a simple stall.
The motor doesn't sound very fast to me. I don't know the details of the motor- but that prop size isn't huge either for 900kv. could it be people normally run it on 4s at that kind of prop size?
Even if it's not generating enough thrust that was still a real nose dive. If you only set the c of g a little nose heavy it looks pretty extreme to me?
Pity we can't see the amp draw on take off on the mfd. My first thought was the plane was only drawing 15A by the sounds of it.
If the video was fuzzy there's no chance the MFD was playing up and inverted elevon control was there and slipped itself into stable mode?! It just looks too positive nose dive to be anything other than elevon induced.
As I said earlier I always maiden with full throw on servos but I have 50% option for dual rates if it's too twitchy. But that wouldn't have saved you anyway.
Having said all that it's very repairable and you will probably fly it more and enjoy it more now it's less pretty :)
Could it be the motor thrust angle?
To me that never levelled, it was in an arc the entire time only when Krikey initially threw it did it overcome the arc. That would suggest to me thrust angle and elevator set too low. Lack or airspeed over elevons and the motor thrust angle made it impossible to recover from.
Did you calibrate the esc throttle end points?
Thrust angle -
(https://farm9.staticflickr.com/8593/16204021719_280c0782ef_c.jpg)
Documentation for Thrust angle
(https://farm9.staticflickr.com/8621/16204343337_90898007f2_c.jpg)
Does that look about right. Angle would appear to thrust upwards ? As mentioned it didn't seem to have much push, did it perhaps so little effect, that Neils throw just continued in a parabolic curve ?
Quote from: Jake Bullit on January 28, 2015, 08:29:06 PM
Did you calibrate the esc throttle end points?
Yes
Quote from: Billy_boy_2010 on January 28, 2015, 07:01:49 PM
The motor doesn't sound very fast to me. I don't know the details of the motor- but that prop size isn't huge either for 900kv. could it be people normally run it on 4s at that kind of prop size?
It looks quite beefy, but is only rated for a 3s
Quote
Pity we can't see the amp draw on take off on the mfd. My first thought was the plane was only drawing 15A by the sounds of it.
I'll measure this on a seperate amp meter
Quote
If the video was fuzzy there's no chance the MFD was playing up and inverted elevon control was there and slipped itself into stable mode?! It just looks too positive nose dive to be anything other than elevon induced.
The DVR shows that the MFD stayed in MAN mode (top left), so doesn't seem to be that. In this mode it shouldn't do anything at all
It's kind of back together now, the nose looks very ugly now though, need to fill in all those gaps
Maybe give it a little up-trim before launching this time, see if it helps? And buy krikey some spinach - I really can't think what else it could have been other than a stall.
Thinking ahead to your rebuild here`s a useful video to help with spar removal.
Zeta Science FX-79 Buffalo - Wing Spar Replacement (http://www.youtube.com/watch?v=q8xd3kePSkY#ws)
Ah mate, gutted for you. It doesn't look like a stall to me, if you hadn't of already said you'd checked and double checked the direction of your servos I would of said it was reversed.
How much does it weight? Its got so much wing area it must just float.
Worth trying a test glide before another full power launch?
At least its not a write off.
Same motor as my FX61, I'm also on 3s but using a 10x7 or 10x8 APC prop....... It has plenty of go.
rgds,
Marcus
Quote from: Jake Bullit on January 28, 2015, 05:45:21 PM
CoG to far forward? Not enough throttle? To heavy for power unit?
Elevon throw reversed?
Motor reversed?
Prop on backwards?
That throw was to steep.
Should have walked up that hill, or used a bungee.
Did you have any wind in the nose, that would have helped to.
Might have been better to try it line of sight with just the battery ,motor and esc before weighing it down with FPV gear.
Could have been any of the above really, at least it's fixable.
Just my thoughts.
all Jake says,fly it los first and always stand closish behind it on launch..
Feel sorry for you man :( Such a nice plane. The only thing I can come up with is not enough up elevon. My experience with wings is that you need a little up elevon for launch, why...I don't know. It definitely wasn't a stall, 9 out of 10 they roll over and spin and it was to controlled. If you go to this link https://www.facebook.com/video.php?v=1469515149937951 (https://www.facebook.com/video.php?v=1469515149937951) you see me trying to Launch a Skywalker X-5, I am using a launcher and even with the high launch speed it just noses over, as controlled as it happened to you, luckily no damage but I was surprised as well. After looking at the images it was clear it was a controlled dive, so I went out again, trimmed up elevon and they're it went https://www.facebook.com/video.php?v=1469521006604032 (https://www.facebook.com/video.php?v=1469521006604032) . For me this is how it works with wings also with my X-8.
http://youtu.be/UeFcSFkVD3o (http://youtu.be/UeFcSFkVD3o)
I hope it will work for you to GOOD LUCK!
Really sorry to see that bump, it went with a real thump!
From the vid and my experience with my Zephyr etc that looks like a lack of reflex, you had enough air-speed for that wing area and as it gains speed it dives harder, reflex IMo.
Chin-up fella.
I think enough has been said already, and I think the concensus is that it was not a stall.
Wayne, I never liked the look of that slow fly style prop and to me it sounded horribly underpowered - that's just an observation.
Did you do any kind of range testing on the Dragon Link...? The input to down looked so positive I'm thinking it may have bean a total RC blackout... shit it's hard to tell. I also like Ian's and Steve idea on thurst angle & power etc. Either way, it could have been a combination.
Awful, sorry! FIX IT!
Dosen't look like a stall to me, the throw was fine, theres plenty of power in those 3s systems to get em up, i would check servo directions, auto pilot orientation and your mates javelin skills, get him ready for Rio ! The only time i had a nose diving incident with a wing was when i was experimenting with extreme hopping on my EZUHF, it happened 3 times during the test, a sudden loss of signal, was only flying line of sight over long grass and having not set a failsafe it just nosedived ! Having gone back to fixed frequency on the ezuhf i haven't had a problem, a bit off topic but hope you sort it out.
Thanks for all the suggestions and observations so far - although there's a lot to consider, I will be doing the following.
1 - Fix plane. In progress and almost done, nose is pretty ugly now but we'll try and smooth it out
2 - Test motor, if it feels weedy then perhaps it is. Will test on watt/amp meter to feel how much it's putting out. ESC is 40A I think, so you'd think it would get into the 30s at full throttle
3 - Range test DL, this has previously been out to 10km on FBS's penguin, so you'd think it would be ok, and RSSI was at 99% all the way into the ground, but a ground range test certainly won't hurt
4 - Trim the elevator up some more
5 - Sort out MFD display issues
6 - Find someone with very soft long grass and do a few LOS throw and glides before committing to a proper flight
Sorry about the maiden but it'll look as good as new with a bit of tlc !
It put me in mind of my first launches with my Z2, I didn't realise how much positive reflex was required in the standard setup which may or may not be a factor with yours. I had several heavy nose ins that didn't do much for its looks. Now with reflex sorted and plenty of power, it gets away every time no probs and it's fantastic to fly, I recon the 79 will be the same. ( sorted the cosmetics after sorting the launches :D)
With my funjet I've had some great flights, but the last 2 attempted launches nose ins... being a bugger to launch, I've learned to always launch it over an area of uncut long grass and undergrowth from last year which has saved it from any serious damage ( as you've suggested ). I enjoy your vids so good luck and I look forward to the one of your upcoming succesful maiden !
Made a great noise when it went in though. ;D ;)
I was suprised at how well the nose faired.The FX61 wouldn`t have come out as well as the nose is a bit more pointed,while the wider nose on the 79 probably spread the impact a bit better.
Quote from: CurryKitten on January 29, 2015, 12:45:30 AM
2 - Test motor, if it feels weedy then perhaps it is. Will test on watt/amp meter to feel how much it's putting out. ESC is 40A I think, so you'd think it would get into the 30s at full throttle
I really don't understand prop size, current draw, thrust values etc- so forgive me if I'm saying something you fully understand :D
but on a slow old wing of mine I used to run a 11 x 6 prop with a 4s. This maxed the 750kv motor out at 350W. It flew ok but cruised at 60% throttle on about 15-18A and I wanted something with more thrust.
I foolishly put a bigger prop on it- a 12 or 13 x 6 from memory- an online calculator said it would kick out 400W and an extra 400g of thrust- and it was a nightmare to launch. Several failed launches I just got it in the air - but it wasn't much good.
Anyway- I decided that the prop was so big the motor wasn't able to hit its max kv on launch- hence why it couldn't get in the air even after a big throw.
If a different member on here is running the same motor as you and using a much smaller prop it may be worth subjectively comparing the thrust to see if there's much difference?
I agree there more to it than just the motor output though.
Just a bit more up trim on the elevon, or reflex as they call it, and you will be fine ;)
Any progress with this? A re maiden due any time soon?
I was going to try and remaiden at the weekend, but I found that the carbon spar that runs through the main fuse was very slightly warped (after a rapair). The carbon rods from the wings slot into this, but it also fits tightly into a ratainer in the wings which can be tightened. Where it was warped it didn't go in properly. So I Need to replace this - I'd assumed my repair was ok... duh. As soon as I get this sorted, it's good to try again.
Ah bad luck.
Sounds like it was a fairly easy repair all in all.
Will keep an eye out for the remaiden
Looks to me like you where to far forward on the cog, and not enough reflex.
IMHO, I would probably look to test glide it first over long grass.
The way the arc tightened in on itself suggests to me the AP was interfering making things worse, either that or it was trimmed for a nose dive. i agree with what others have said about the ailerons requiring some added reflex
Ok, time to give this another go. Off to visit FBS on Saturday, and finger crossed the rain will hold off to give this and his new MFT a fly
I'll bet 100 quid that this was not a stall. Generally when these things are launched there is a period where it's just using the momentum from the launch to stay in the air, the thrust from the motor builds up the speed and by the time the thing would be falling back to earth, it's got enough speed and is flying.
This is how the Harriers launched, when it left the ski jump they weren't flying fast enough to maintain altitude. The jump just placed them on a parabolic arc and by the time they would drop down, the speed was up and they were climbing away.
Incorrect thrust lines are also out of the question as the effect would be immediate upon launch. As I said above, immediately after launch the wings aren't doing all that much and so if the thrust lines are off, it'll flip over almost instantly. This has happened to me a few times when I've accidentally bent a motor mount on a wing and launched without realising.
All I can think of is what's been said before, a control input by something or other. How was your failsafe set?
Quote from: CurryKitten on June 19, 2015, 12:38:57 AM
Ok, time to give this another go. Off to visit FBS on Saturday, and finger crossed the rain will hold off to give this and his new MFT a fly
Hi Wayne,....good luck m8, and please, please dont launch it again wearing goggles, you just cant see whats going on properly....What do I mean?...if the model is launched upwards at an angle (like last time) all you see in your goggles is sky, no perception at all of forward speed, or indeed if its even been launched?...hope that makes sense.....At least until you have the elevons trimmed, and I would set some more up on them, its easier to handle than not enough for sure.....:)
:vulture:
There wasn't a chance Wayne could have saved that first launch, everything happened too fast. I had a similar crash before I believe mine was caused by autopilot setting throttle to high on the powerful motor and the plane simply nosedived.
Good luck this time around, worth checking and rechecking everything a couple of times before launch.
Good luck buddy!
The plan this time is to give it a few unpowered glides. It's not that heavy, and the wing area is massive, so it should be floaty. If that's good then I will aim to power up after the throw and make sure it's ok LOS. I'm an awful LOS flyer, but even I should be able to go 100m in a straight line and put it down again.
If it's not smashed up by this point, the goggles go on.
Got a bungee you can try if you get really pissed off!
Sounds like a plan, but I'd take off Los and switch to fpv as my Los flying is rubbish too!
As before get yourself on a hill or bank where the ground falls away in the direction of launch,a headwind will help,good firm chuck about 15 deg above horizontal and about 70% throttle,maybe a a couple of clicks of uptrim.
Good luck :)
Getting yourself on the bank or hill helps if you have a slight problem e.g. plane to heavy and lose height while gliding. In case of immediate nosedive it makes things worse as there is more height to fall from.
Quote from: highlander on June 19, 2015, 11:38:25 AM
Getting yourself on the bank or hill helps if you have a slight problem e.g. plane to heavy and lose height while gliding. In case of immediate nosedive it makes things worse as there is more height to fall from.
I disagree- a nosedive at say 45 degrees towards the flat ground becomes a 25 degree nose dive towards a 20 degree downward slope- much better. The few extra feet of fall height is far outweighed by this.
Good luck Curry.
IMO
Keep all autopilots etc off
Set it up with the lightest battery combo possible.
Throw in long grass into the wind a few times.
Launch LOS. I'm a terrible LOS pilot but, unless the plane is extremely fast, you will be safer than fpv.
Have a friend click the trim while you just fly it straight. Having said that I find trim easier to do fpv provided she flies well enough to fpv it.
Set up dual rates on the tx. If it's way too twitchy on the higher rates switch to low.
Also why do some people always advocate launching on 70% throttle? Unless it's hugely powered and likely to torque itself into the ground (like a funjet!) full throttle can only make the launch easier imo.
Also maybe run and throw the plane while running? Gives you a few extra mph on launch.
Good luck 👍
Quote from: Billy_boy_2010 on June 20, 2015, 12:14:48 AM
Quote from: highlander on June 19, 2015, 11:38:25 AM
Getting yourself on the bank or hill helps if you have a slight problem e.g. plane to heavy and lose height while gliding. In case of immediate nosedive it makes things worse as there is more height to fall from.
I disagree- a nosedive at say 45 degrees towards the flat ground becomes a 25 degree nose dive towards a 20 degree downward slope- much better. The few extra feet of fall height is far outweighed by this.
Good luck Curry.
IMO
Keep all autopilots etc off
Set it up with the lightest battery combo possible.
Throw in long grass into the wind a few times.
Launch LOS. I'm a terrible LOS pilot but, unless the plane is extremely fast, you will be safer than fpv.
Have a friend click the trim while you just fly it straight. Having said that I find trim easier to do fpv provided she flies well enough to fpv it.
Set up dual rates on the tx. If it's way too twitchy on the higher rates switch to low.
Also why do some people always advocate launching on 70% throttle? Unless it's hugely powered and likely to torque itself into the ground (like a funjet!) full throttle can only make the launch easier imo.
Also maybe run and throw the plane while running? Gives you a few extra mph on launch.
I agree with what you say, apart from running and throwing, the extra coupe of mph will be wasted because of the poor throw you'll end up doing.
Good luck bud!
Good luck Wayne! Remember, wings can sense anxiety and that's when they attack. Be brave and take charge, give it a firm chuck and tell it who's boss!
Way too much overthinking in this thread.
Just give it some beans, chuck it at 45 degrees then get your hands on the sticks. It'll be fine, they usually are unless something is WAY off, and it won't be that bad - you're experienced enough now to have a rough idea of gear placement.
Quote from: Steve W on June 20, 2015, 12:41:23 PM
Way too much overthinking in this thread.
Just give it some beans, chuck it at 45 degrees then get your hands on the sticks. It'll be fine, they usually are unless something is WAY off, and it won't be that bad - you're experienced enough now to have a rough idea of gear placement.
Exactly, just give it a good chuck 3/4 throttle nuff said :D
Well then did it fly? ^-^
I am beginning to fear tales of wreckages and girly throws maybe coming.
Fingers crossed.
Either way I want a vid of sorrow or joy :D
Video uploading, prepare for sorrow
... and done
! No longer available (http://www.youtube.com/watch?v=2JJ14guOeRY#)
I do like to think I've generally got the hang of flying planes these days, but I'm buggered if I can get a handle on this one. Perhaps the scale of the thing is messing with me, or something else. I don't know. We'll glue it back and try again in due course... stubbonness will force me onwards and get this sodding thing in the air
Oh no :s
The first glide was perfect. Just perfect. Did you change anything between the first and second throw? You could have powered up after the first release and been fine. If the motor is powerful enough you can do this.
I fear, perhaps with a bit of wind, the position where he held the plane lends itself to pitching up a fair bit. This plane certainly doesn't like being thrown up at any kind of an angle.
That first glide must have been encouraging, as we are saying on shout the second is the launch but that was more unlucky and finger position than a bad chuck.
Definitely looks like it needs to be launched with the fingers on the trailing edge :(
Just looked liked a dodgy angle on the throw on the second attempt to be honest :o
"Richard moderately worried about me cutting his fingers off..." .
Looks like the worry caused the stall.
I don't know what autopilot you are using, APM has got a feature in auto mode where motor starts only after the plane achieves pre-set speed. That way the motor will only start after the propeller clears the throwers hand.
After all it is hard to keep cool when one is (unconsciously) aware there is a spinning blade waiting to inflict damage on thrower's hand, I'd say the bungee/ catapult launch is ultimate solution.
First throw was perfect and proves that the plane is trimmed and will fly. Look how far it went!
The second launch was at to higher angle. As Rich goes to throw it the weight transfers back and pitches the nose up. Having his second hand on the talking edge helped stop that.
That's the problem with finger homes near the cg, the plane is to free to pitch up and down.
I wouldn't want to throw it from the holes with the power on, I'd launch it like a big wing from the leading edge baseball style.
Hope it is repairable mate. Shame your not coming to MD.
Oh and please don't go down the bungee route, you've seen how long it takes me to setup!
Holding the aircraft at it's CG during launch is always tricky, you simply don't know were it will go...nose up or down. Throwing it base bal style (holding the leading edge) may do the trick. On the other hand if you just powered up during the first attempt......but I understand your carefulness. For me a launcher does the trick (build one for my X-8) less time to setup compared with a bungee.
The other 'hybrid' option for the hand launch is to use the finger holes like Rich does in the second launch but also use your other hand to steady the nose or leading edge of the wing, hopefully that will steady any attempt to pitch-up. Another option depending on your flying location would be a dolly as there's no setup to worry about just a bit of extra kit to carry.
Finally, some positive news
! No longer available (http://www.youtube.com/watch?v=YgFb_Z8fKyc#)
Hey that's excellent!
To what do you attribute the success this time?
How large a battery was she carrying?
I really need to get my head around the in flight tuning. It seems very effective.
Not trying to throw it, but instead FBS just pushed it forward... if anything downwards. This let us get the power on and get up in the sky. We also did this in STAB mode, as we hoped this would deal with any tendency to nose up
It only had 5000mah in there, it should carry 10,000 quite comfortably though.
I don't really have much of a clue on the in-flight tuning either, Rich just told me what he thought, and we kept trying things until it was smoother :)
Congratulation lads ! It was painful watching that beautiful bird crash, must be real pleasure now you;ve got hang of it. We need next milestone 40 km. ;)
Nice one wayne! Glad you finally got it up
About time lads ! :) :) :)
Well done getting it finally of the ground guys
Looks to me like the launch fiver holes are behind the cg.
Causes a pitch up!
Glad all working now.
So are we all in agreement that the cause all along was the launcher then ? :)
:terrific: :dancing2: :yahoo: :pint: :pint: :rocks: 88) :grouphug: :gotit: :flying: :party: :clap: :thumbsup: :terrific: :bravo:
Glad to see you got it flying and didn't have to take it away in bits again! 88)
Quote from: Coyote on July 06, 2015, 09:22:54 AM
So are we all in agreement that the cause all along was the launcher then ? :)
(What a lil' biaatch :) )Although this is Wayne's plane I must say I, and my reputation were pretty heavily invested in this flight. The launch should be absolutely straight, and then lowered to compensate for wind, so perhaps every km of wind it's maybe ish a little down, and as you see it gets it's own legs pretty quick.
What Wayne didn't mention is that every time I grabbed hold of it to launch I double checked to see that he had his thumb locked down on the throttle. Last count, 10 fingers! Yay, Holly has a piano teacher still :)
I read somewhere about someone launching this wing solo? I'd love to see how it's done! It's a damn pity though that we never tried Auto Launch, but I suspect with full power and 20% up combined with STB it should (???) take off, provided that thrust kicks in pronto. If it did work it would make for a very different take off and not the gentle shallow climbs we saw here. The motor and prop is not a screamer, but there is a fair amount of torque and thrust behind it.
Rob, I think you're right (check with Wayne?) that the holes are not quite the CG point. Whether they are or not, I can't see how they can be used for launch anyway because they are so big - good enough for a hand hold yeah, but once the wind gets under it, one's little fingers are not strong enough to keep the nose straight, or slightly down.
Gonna have to keep it for special occasions and fly with a mate I think.
+1 to those who said this plane is for range!
Anybody else notice zero tail wag?
I dig it, well done Wayne!
Quote from: Flyboysee on July 06, 2015, 09:57:32 AM
I read somewhere about someone launching this wing solo? I'd love to see how it's done!
I can't believe you've not come across the very squeaky voiced Jase, friend of the BMsweb guys. He seems to launch this no issues making it look very easy indeed.
! No longer available (http://www.youtube.com/watch?v=A36txtooLIE#)
That's a BIG BIG run up! Rather you than me - that's a BIG BIG prop!
:gotit: :gotit: :gotit: :gotit: :gotit: :gotit: :bravo: :bravo: :bravo:
Question. ..
How does it handle it's stall ?
I just wonder if the pitch up on launch is the cog being too rearward?
Hi guys....
I've not had my FX-79 for long and my maiden went very well....
2 flights later I drove it into the ground.... Flying again now so all good but...
I launch solo... I would say you need a good lump of throttle and a smooth, javelin style throw... as soon as you let go, get on the sticks and pull up.... not too hard just enough to keep her flat and level....
This this is a dream to fly, it's just that launch.... :+
Hehe, I've just had a read back through the thread. A good way of experiencing all the stress again :)
So since those successful flights, I had the whole hassle with the MFD blowing up, and that VTX was dodgy. I've got a replacement MFD now (but untested) and can swap over the VTX so in theory I should try again.
It has at least got to the stage where I'm not at all precious about it. If I can't get to the stage where I can chuck it and fly it myself, then it'll go in the bin (probably in pieces after a dodgy launch)
I hope to get on with this soon, but I've been off sick for the last 4 weeks, so have jut been at home feeling crap and missing all this nice weather :(
KillerDave. Just to check your setup. 3s/4s and what prop ?
Leopard 3240 900Kv motor,
2 X 3s 5200mAh LiPo's,
Aero-naut CAM 12 X 5.5 folding prop.
If I launch flat, and at 3/4 throttle, I am sure it would hit the deck every time, I give it and 10-20 degrees up and on the sticks as soon as possible.
Looking at your videos, it looks to me that your friend throws it quite hard and abruptly...???
This (I think) would make the plane pitch up hard due to the mass being above his hand and turning the point at which we throw from a pivot point???
Once in the air, this thing almost flies itself..... ;)
Looking forward to seeing this bird fly again, Wayne.
I was al ready to fly this evening but mother nature had other ideas!