Crash-RCU

Has anyone flown this plane. The instructions call for 20mm on the ailerons and elevator, that just seems like to much. This plane is all foam that I glassed and put a spruce spar in instead or the soft balsa ones. The instructions called for .15 but I am using A Norvel 25 bb with A ready to fly weight of 2 1/4 pounds with no fuel. Should be in about the same class as A Wonder not exstream but should still be fairly Quick. Just think that it has to much control throw. Should have said that was 20 mm each way.

cabanestrut2002

sorry to dissapoint, but it wont be too fast, its got lots of jagged bits and many surfaces, its very draggy and fat, they are great fun though.

it will fly verrrrrry slowly.

i cant remember how much throw the one i flew had, use your judegment, its quite soft on the elevator and rudder, ailerons are more effective.

go with what the instructions say and change it to suit your taste.

afpe45

@Crash-RCU.

So how did it fly and is it still flying ?. have you done any more mods ?.

afpe45

BaldEagel

Hi Crash

I have as much movement as I can get on mine, the aelerons are very soft otherwise and do not harmanise with the elevator, mines electric with a Mega 22/30/3E running on a 3S2P 5000maph LiPo its very stable even boring to a certain extent, until you slow it down and start to do silly things with it, prop hang, harriers and very slow rolls, oh yes nearly forgott it bounces quite well.
Mike

afpe45

@BaldEagel.

Hi Mate,
I am building mine (had it in the box for a couple of years) and am thinking of glassing it.
Have you glassed yours ?. whats the flying weight if so ?. have you extended the elevator & aelerons(ie with stock balsa)

I started a thread asking for info from people who had glassed theirs, on Watt Flyer but no info yet.(a couple of helpful links)

Mine is also electric , Using a Typhoon mini 29/12/10 ,driving a 10x6 folding prop(Aero-naut CAM),
powered by two kokam 3200-20c 2s 7.4v lipo packs,connected together with a series plug to get 14.8v 3200mah lipo pack , I believe that is1p4s (might be wrong) this is my first time with lipo's.

(these were recomended by MR Smettam (forgot his first name) from the electric aeroplane company , at chester last year.)

What should I expect from this setup ? I am going to put a stock balsa elevator to give it more response , dont know if I should extend the aelerons and I am waiting for info as to weather I am going to glass it or not.

Cheers.
afpe45.

BaldEagel

afpe45

The weight of mine is 916grams without battery, stock control size's, the only mod was to put spruce spars in instead of the balsa ones supplied in the kit, the underside of mine is taped with that clear fibre reinforced tape that you can get anywhere, the underside needs to be a totally different colour to the top as orinentation can be a problem at distance. in between the two hand hold points on the underside I have a large hole throught to the inside for hot air to escape, its obviouse where this is from the inside as a hole is already in the ply floor former, I just burnt it through with a soldering iron, see pics.

I understand that Ripmax no longer do the I.C. version, so its lucky I have one in my loft ready for the enevitable day that I need it. A flying pal of mine has the I.C. version which is not as fast or as manouvreble as mine, smaller movements on all controlls, his is not protected on the underside in any manner and its been flying for 2 years at least, so I think the galssing may not be neccessary, just some protection from landing.

Your designation is correct for the LiPo except reversed i.e. 4S1P, have you seen the latest Flight Power EVO 20 LiPo's 20C continuous 30C Bursts, I'v just got one in 2500mAh which I will try this week it weighs 214grams as against 352grams for the 5000mAh saving 138grams should make a difference to the flight envelope, we shall see.

As to the performance you can expect, on a 12 x 6 I am pulling 34 amps which works out to 116watts/lb this is adequate performance will fly right out of my hand for launch and is I think at the maximum speed that can be achived with this plane even diving does not increase speed that much so I think its a terminal velocity for the aerfoil already. If you do not know how to work out your watts/lb post me and I will explain.

Regards
Mike

afpe45

@BaldEagle.

Thanks for that usefull information,

could you transfer it to my thread on wattflyer at: http://www.wattflyer.com/forums/showthread.php?t=3654
Because that is the type of info I was looking for
I presume your old lipo pack was 5000mah what flight times did you get from it.
and yes I do need info on the watts/lb thing (amps too) , If you are transfering your last post you could post the info there as well , I know nothing about lipos this will be a big help, I am even a bit frightened of charging them, I am getting it slowly , my charger shulze chamelion charges 1 to3 cells,
so I will have to charge my two 7.4 packs seperatly at 1c(3200mah) but at what charging rate I am still a bit confused help here would be usefull as well

thanks.
afpe45.

PS: More pics as well

BaldEagel

afpe45

I'm already on too many sites, I rearly do not need to get involved with another one, I'm just going to stick with RCUniverse if you don't mind.

Flight times where such that I ran out of current before the LiPo's 2 maybe 3 10mins flights, when you see others talking about 20min flights with a 1200mAh battery, use the salt sparingly. yes my LiPo's are 5000mAh Fight Power's with ballancing circuits. I never charge at 1C at the most 3/4C sometimes even lower if the pack has not been used and I'm just topping up. I charge my 5000's at 2.5 amps, I have been using LiPo's since they became available and never had any trouble I did not expect, don't leave them alone when charging they seem to get lonly puff up and throw there dummies out of the pram. Seriously if its going to go wrong it will when you are not there.

As too the Watts/Lb thing, i'v pasted this from the "Ultrafly PC9" Thread where I posted it earlier, so if its out of context please excuse, I think it should give you what you whant.

50watts/pound is Cub performance.
75watts/pound is aerobatic performance.
100 watts/pound is 3D performance
150watts/pound is F5B or hotlinner performance.
All approximate
these Yardsicks were established in the days of brushed motors therefore with the increased effeiciency of brushless we gain power. And with LiPo's we loose weight, win win all round.
Therefore if you multiply Amps x Volts to get Watts you can assess the power required.
Alternativly multiply Weight in pounds x performance Wattage required divide by Volts this will give you Amps.
From the above you can work out wich AXI motor you need.
Therefore 3.25lb x 75 / 11.1 = 22.8 Amps.
and 3.25 x 100 / 11.1 = 29.2 Amps
and 3.25 x 150 / 11.1 = 43.9 Amps

Taking the middle of the efficiency current of the various AXI motors we come too:
2814/12 on a 9 x 6 for 75 watts/lb @ 3/4 WOT (this motor will take 35amps for 60s, best bet I think)
2820/8 on a 11 x 5 for 100 watts/lb @ 3/4 WOT (this motor will take 55amps for 60s)
and then we go outside the efficiency ratings for a reasonable motor for this aircraft at mid efficiency so at max current capacity:
2820/8 which is 55 amps for 60seconds only on the same 11 x 5 but pulling max revs, perhaps experimenting with props to assess amps pulled. This is all assuming 3S1P at sufficient C rating to allow this draw.
I know this is a converluted answer to your question but it gives you sufficient information that will allow you to do the calculations for yourself in the future.
Hope this is clear, if not post me and I see if I can make it clearer.

Additional information a normal 0.40 size glow engine will produce approximatly 1/2hp which is 375watts if I remember correctly.
Regards
Mike

Hope this helps if not let me know.

Mike

afpe45

@BaldEagel.

Thanks for that (and for transfering it )

cheers.
afpe45.