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Dodgy Crasher
Strange thread, trying to make the Eurofighter V5 slower, I fitted a 28-36 2700kv ntm propdrive motor in mine, rounded off all the leading edges for slipperiness in the air, run it on a 45-90 discharge 3s 2200 lipo with a 60a esc and a 3 blade prop,  it just drifts along nice and slow and quiet at one quarter throttle,
it flies perfect with not much noise at half throttle
but when you want ðŸ™€ it's got that too at full throttle along with lots of high pitched whine ðŸ˜, I have considered some surgery to make the cannards work, might still do it when i get some spare time.
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shadeyB
Strange thread, trying to make the Eurofighter V5 slower, I fitted a 28-36 2700kv ntm propdrive motor in mine, rounded off all the leading edges for slipperiness in the air, run it on a 45-90 discharge 3s 2200 lipo with a 60a esc and a 3 blade prop,  it just drifts along nice and slow and quiet at one quarter throttle,
it flies perfect with not much noise at half throttle
but when you want Ã°Å¸â„¢â‚¬ it's got that too at full throttle along with lots of high pitched whine Ã°Å¸ËœÂ, I have considered some surgery to make the cannards work, might still do it when i get some spare time.

lets see those canards activated pilot 👍 
Fly it like you Stole it [smile]
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Dodgy Crasher
Ah thank you Shadey for the clip of my now named murder wasp as Peter called it, others might call it a brightly painted V5 Eurofighter built from plans bought on this very site, plug plug, hint hint, you know you want one.
Anyway as I was saying before, it sings at high revs and is really fun and very stable even without the moving cannards, a feature to be installed on this one or maybe another build but with a proprdrive 28-36 3000kv motor for even more speed ðŸ˜›ðŸ‘
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unclejamal

Hi guys,

since my F-18v3 already had a lot of repairs and was gaining weight, something new had to be built - the EFv5. i chose it, because i wanted a delta wing again, since the RCPowers X-31 was so great to fly.

DSC_1528.jpg  DSC_1532.jpg 

overall weight including components, exclusive the Lipo is 365 grams (with a 3S 1800mAh Zippy Lipo its 530g) - what a lightweight! Motor ist the HK 2200kV

note, that i did small modifications in order to fit a 7x4 prop (due to noise abatement). This induced the following adjusments, beside increasing the prop slot width:

  • shift the engine nothces slightly outwards
  • in order to compensate the loss of wing area, the wings have been enlarged by about 1/2 inch in width. the main wing was also enlarged towards the front by some extend - note the gap between the "canards" and the main wing is a bit shorter than on the original plans
i tried to do a lot of details like edge rounding/bevelling, adding leading edge slats. The ailerons/elevons have been slightly increased in size (width and length).

expectations have been very high for the maiden. but maiden was a bit staggering. why?...
  • bigger prop was not quieter than the 6x4. i guess the airplane is not quite solid in the area of the prop slot and it sounded like some resonance was created by the wingplate/frame
  • flight behaviour was not as expected. roll rate was not that fast and it was little bit a torque roll. making a turn was quite different than my F-18v3, Tucano, FRCF F-16mk1. just bank and yank was not enough for the turn, i had to apply pitch in order to turn. the behaviour of the rudder was also strange. when applied, the plane was not just yawing, it was flipping over instead.

unfortunately that was the first time i was disappointed with an RCP plan(e). also because i invested a lot of time for making the details (bevelling, painting,...).

 

 

 

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djdazzy

Should have kept to the stock plan 🙂 Dave spent hours perfecting these planes.... it would have probably been better scaling to 133% and fitting an 8 inch prop and 1400kV motor.

You increased the prop size but never reduced the motor kV which will result in no noise reduction. The noise is down to the speed of the prop tip interacting with the air to a very close slot edge.... increase the slot size will reduce the noise or putting on a 6 inch prop. The bigger prop will also give you a greater gyroscopic effect reducing roll rates.

Crashing since 2013.
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Sidewayskiwi
OK
On youtube there is a guy doing vids on propslot designs 
bigger slot=less noise
bigger slot=more thrust 
the design of the slot(shape) has a lot to do with it as well
From your underside pic i can see edge gap is too tight (more noise) and the rear deck structure is too close (angled in) to the proptip -- this point is highest airspeeds = more noise 
I would expand the propslot at the proptips rearwards by 1-2 inches but leave the centre of the slot untouched - creating an X or an hourglass shaped propslot
APC props are the noisiest i have used i recommend GEMFAN FLASH props more thrust for less amps
Find the youtube vids and find power+effiecency with less noise
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Wildthing
You know if I  put my NTM 2700kv motor , 4S , 6X3 prop on as a tractor or pusher or mid mount it sounds the same, loud. 
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lysle42
sound is the good like putting cards in your bicycle spokes. 
Love it.
Homer
<'(((><
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Dodgy Crasher
Hi unclejamal, my v5 eurofighter displays none of the traits you mention, I built mine as per plans with the exception , I run an ntm propdrive 2700kv, and i like the 2200 3s in there to power it,
It glides pretty well when I cut the power considering, it does come down but not a fall out the sky like you might think, I can land easily with no power on the prop.
Also the rudder is great, I do not use it for turns as the plane flies like it's on rails, I do use it when flying in high alpha, you can high alpha in figure of eight if you like, but I mostly use it to keep it going in the direction I want, your problem there might be something to do with you narrowing the gap between the wings and the cannards, maybe something to do with airflow over the wings.
If you watch the youtube video above this reply that is my V5Euro in the wasp like paint job, if you watch it for less than a minute you will see me perform a climbing roll and it turns like a bullet, I usually back it off after a half roll or it becomes a blur, I will say this though, I do not use EXPO 
I also use 100% throws all the time.


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Dodgy Crasher
meant to say also if you look at that video from about 2 minutes 55 second onward for about 10 seconds you will see a full stick to the side roll, it turns so quick, the slight pitching left/right in alpha was actually my fault, I wasn't putting any pressure on the rudder, just a small touch to any side stops that and keeps it going in a straight line, it's a thing I discovered after I flew it a few times, that video was made pretty much when i'd only flown it a couple of times, hope this info helps for your next build, build the Eurofighter as per plans and you will not be disappointed.
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unclejamal
Thanks at @djdazzy, @Sidewayskiwi, @Wildthing, @Dodgy Crasher for your comments. I was aware of the bow tie slot which this other guy investigated. please have a look in this thread where @bogusbandit56 posted the bow tie, and i linked the video there, you are referring to.
https://www.rcpowers.com/post/quietish-motor-setups-for-parkjets-10022702?&trail=30

for a first try i did not make the bow tie, as i could cut it out later.

in some previous (recent) posts within this eurofighter thread, i was already announcing and asking about the topic. wished some of you already participated in the disscussion there... haha
it not that i was just doing my own thing without experimenting, i was gathering the tipps in this forum (this thread and the one linked above). i also contacted a previous (valueable) member: e3_scott, which gave me the same tipps as i got here in this forum. so they have been consistent. That's why i did the bigger slot with a bigger prop.
The slot was enlarged by 1/2 inch on each side only. is this making it such a big difference... apparently 😃
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