FT Mini Arrow

[raneous]

V3.5L

Well here's the newest one. I peeled the waterproof paper for the top side, covered it in colored packing tape, then peeled the bottom side of the paper off. Installed a decent length of RGB LED lights along the box spars. Turned out decent. It's a blast to fly at night! I would post videos but I don't have a Youtube account nor will I be getting one. Need to get an overall weight but it feels very light in the hand compared to my other Arrows. Shedding the paper made a huge difference. *Note I left the paper on the box spars for strength.

 

[Hai-Lee]

That's what I get for living in the land "Down Under", All the pictures appear upside down

Nice work!

have fun!

 

[raneous]

That's what I get for living in the land "Down Under", All the pictures appear upside down

Nice work!

have fun!

HAHAHA! I'm not sure why it does that? It happened in my first posts earlier in this thread. The last batch were fine and then these ones inverted again. I just import them from my computer. I'll try inverting the files before I import them next time and see if that will fix it.

 

[raneous]

So before my next build...... Am I correct in assuming that in order to have the tight rolls like previous builds I will need to sacrifice some reflex/deflection and fly with a bit of down stick/up elevator? I ask because on earlier builds I used the provided reflex gauge and had phenomenal rolls but was flying with constant "down pressure" on the stick. On later builds I increased the reflex/deflection and ended up with a super stable wing at "dead stick" but ended up with sluggish "barrel" rolls even at full aileron. I'm running 9d on my current build and using a bit of down elevator sub-trim. I've tried everything from the 12d suggested on the build sheet to the 8d gauge provided. The 8d provided the best rolls but as before mentioned required constant up elevator. I'm just wondering if I'm missing something or just need to learn to fly with the "Down pressure" for the performance I am craving?

Thanks in advance for any input!

 

[nevenelestate]

I would check your hinges, If you have too shallow of a bevel, or too much glue built up you might not get as much down deflection. Also if you don't have a good glued hinge then when the surfaces deflect up they might be pulling the foam from the paper and not giving a good sturdy surface.

I disagree with the varied throw up vs down idea. IMO you should have equal downward deflection of the one side to make it want to come up, while the other wing is being pushed down by that elevon's upward motion.

 

[thearne3]

Help! Building my first Arrow. Have tested 2 of the four servos that came in the Power Pack F - no response at all. Same setup with standard 9g servos works fine on the Devo RX601. Am I missing something?

 

[thearne3]

Update: last 2 servos work. Guess it's the luck of the draw...

 

[thearne3]

Maiden of my Elmer's foamboard Mini Arrow yesterday. Had to add A LOT of weight to meet the CG listed of 1.75" in front of the firewall. Flying VERY nose heavy, so took out some, then all the extra weight. Current CG is maybe 1" in front of firewall. Reflex is higher than spec as well.

Is this normal???

 

[Hai-Lee]

Maiden of my Elmer's foamboard Mini Arrow yesterday. Had to add A LOT of weight to meet the CG listed of 1.75" in front of the firewall. Flying VERY nose heavy, so took out some, then all the extra weight. Current CG is maybe 1" in front of firewall. Reflex is higher than spec as well.

Is this normal???

The amount of reflex is determined by the angle of attack required to maintain flight combined with the amount of control force required to balance the wing around the centre of lift for level flight.

If your wing is heavier, (higher wing loading), than the one used to determine the original settings then you will require greater reflex angle and also if your wing is nose heavy greater balance force will be required and therefore greater reflex angle will be required.

It is pretty simple concept so check the weight and adjust CG point to get proper flying balance and all should be fine!

have fun!

 

[thearne3]

Thanks for the reply!

I gather that adjusting reflex can offset an improper CG balance. When I started, I had enough nose weight to balance at the 1.75" in front of the firewall specified by FT, but I didn't have enough reflex, so it 'looked' nose heavy and required constant back pressure on the ELE to keep the nose up.

Having taken out the nose weight, I now have a CG balance point about 1" in front of the firewall, but all throws are minimal and high Expo to try to keep control! Relative to the correct CG, my plane is now tail heavy and (from what I've read) so very unstable.

I am going to add back the weight and adjust the reflex for level flight. I hope get a more stable wing!

Hope I'm getting this...!

 

[Hai-Lee]

The best way to see if you have the CG correct is to gain some height, (for safety), and cut the throttle and try to hold the nose up by increasing elevator input to max and watching how it responds. If it GENTLY nods the nose up and down as it slowly sinks towards the ground then the CG is good. If it nods severely then your craft is nose heavy and finally if it becomes unstable in direction, (wanders right and then left followed by a sudden wing drop and dive then the CG is too far aft!

Once you have got the CG correct then adjust the reflex angle to give you the level flight you require!

Have fun!

 

[raneous]

I'm sure it is already posted in this thread somewhere but I don't have the time to look for it right now Here's a link to a flying wing CG tool that can be very helpful. http://rcwingcog.a0001.net/?i=2

If your a noob like me and don't understand what all the technical terms are (Root Chord, Tip Chord, etc.). Here is a quick video that explains what those terms mean and how to use the CG tool. https://youtu.be/DOWqvxxglmk

Then like Hai-Lee said "Once you have got the CG correct then adjust the reflex angle to give you the level flight you require!"

Hope it helps

 

[mikej997]

Scratch build time?

Hi all! I have recently been introduced to Flite Test and found the mini arrow. I do believe I will be around here a lot!
I've built several arrows but am still flying my first one. I probably have several dozen flights and while it is no longer pristine, it is still in good shape. I have wrecked it pretty good a couple of times as well. It does have me wondering, how some of you manage to break the thing in half?!! Wow!
I have built all from DTFB and plans. Obviously, the first one took a really long time as I watched the build video about 6 times to make sure I was doing everything right. Although my build time has been cut down significantly, it still takes several hours from new foam to flying plane. One of the longest parts for me is transferring plans to foam. I have read of several different tricks, making templates and using pins to mark corners.
How long does it take you to put plans on foam and be ready to cut? Right now, that is half my build time. I'm looking for a better way and would like to hear what you guys (and gals) think, especially relative to the one FT plane I'm currently familiar with.

 

[Ricci]

Hi,
I print out the plans and glue it with a easy to remove glue stick to the board. To build the arrow including printing plans takes ma about 4 hours ready to fly

 

[raneous]

It does have me wondering, how some of you manage to break the thing in half?!! Wow!

How long does it take you to put plans on foam and be ready to cut? Right now, that is half my build time. I'm looking for a better way and would like to hear what you guys (and gals) think, especially relative to the one FT plane I'm currently familiar with.

HAHAHA!!! Be a noob and have your CG too far back! If you get it to stall and dive straight into the ground from 2 mistakes high you should have no problem getting it to rip in half:black_eyed: I've torn 2 in half now

I get the speed build kits from FT and it takes me about 1hr to 1 1/2hr to build and maiden providing I'm not peeling the paper/adding LED's etc....

I haven't built one from the plans yet but it seems like a lot of the guys that do make templates to help speed up the process. If you wanted a perfect start you could order one of the speed build kits for $15 and use it for templates instead of building it. Pin it down to your foam board and trace maybe? Like I said I have no scratch build experience so not sure if this would work but it seems easier than gluing sheets of paper down.......

 

[jaredstrees]

Fly it into a chain link fence at full throttle.

 

[Ricci]

Hot glue will fix it.

 

[mikej997]

Ouch!

She looks as sad as I'd be after smashing one like that.

The mini arrow is the first wing I've flown, my other plane is a glider, so muuuch slower. Probably on my Arrow's second flight I was trying to get some nose up trim set and completely fat fingered the controls. Ended up rolling the plane over and diving vertically into the ground about 70% throttle from about 30 feet. Luckily I didn't have the FPV camera in it yet, so the battery coming out through the nose foam was the worst thing that happened. I poked the battery back in and flew it twice more, then repaired it later at home. My motor isn't the best though, I've got a new one on order from FT that should help a lot.

My son is thinking that we need to race these so I imagine there will be a smashed one in my future at some point. Right now my hobby has become scratch building these. I am getting faster and am developing a system. The last one went from blank DTFB to maiden ready in a shade under 3 hours.

Here is my current collection. The red one is the one I nose dived into the ground. I added some reinforcement and camera guards on it. I haven't flown the other two yet. I would have to say though, having a spare or two has made me a lot more bold in my flying!

Mike

 

[jaredstrees]

Always good to have a backup! I usually have at least one for all the planes I really like.

Worst part about that crash was I destroyed a brand new 3s 850mah battery. Actually very surprised it didn't ignite as there was an indention about 3/8" deep in the battery from the chain link.

 

[nevenelestate]

Always good to have a backup! I usually have at least one for all the planes I really like.

Worst part about that crash was I destroyed a brand new 3s 850mah battery. Actually very surprised it didn't ignite as there was an indention about 3/8" deep in the battery from the chain link.

It's surprising what will and will not ignite LiPos