'70mm class EDF Speed Cup Challenge' - Page 2 - RC Groups
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Dec 09, 2012, 04:14 AM
efflux RC's Avatar
Similar info regarding a thermometer at the field.

Habu2 contest:............................(that's one of my slower ones. never entered the 161mph version.)

It was an over cast day......no sun.
Habu - Shubie on 7s (7 min 54 sec)

One comment about the temp from the Habu32 race thread:
On a separate note, I would suggest you add the requirement to show ambient temperature on the video. If Doppler will be used to measure speeds this is an important factor.

Don't forget temperature for the guys doing the Doppler!

I'm working on the wording for the Doppler temp. requirement.

For some reason, they failed to add it to the official rules, but everyone abided by it and posted the temp at the field.

Below are some of the VIDEO parameters for the SAPAC Viperjet speed contest:

"Each Video Submission needs to include all the following elements: "
  • ................
  • An ambient temperature reading using an ambient thermometer (we are looking for air temperature, not the temperature of any given surface)
  • ...................................
Viperjet contest:

Sapac Viper Speed trial 2.mpg (6 min 35 sec)
Last edited by efflux RC; Dec 09, 2012 at 04:25 AM. Reason: added text
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Dec 09, 2012, 04:52 AM
Lee Liddle
Knife Liddle's Avatar
The 1/2 scale version of what my first attempt will look like is just about ready to maiden.
Dec 09, 2012, 12:42 PM
Caution:Makes sharp left turns
Troy's Avatar
That's really cool looking, btw.
Dec 09, 2012, 01:20 PM
Lee Liddle
Knife Liddle's Avatar
Thanks Troy, here`s the thread in the micro edf section.

Dec 09, 2012, 07:37 PM
Lee Liddle
Knife Liddle's Avatar
Originally Posted by Knife Liddle
The 1/2 scale version of what my first attempt will look like is just about ready to maiden.
I did a quick maiden on the 35mm speed jet. It flew great, even in the 15mph wind.

It needs no reflex for level flight! I had it set up with some reflex to start, and I actually ran out of down trim trying to get it dialed in. I may need to shift the CG forward a little bit so that it doesn`t need down trim. LOL

I know I promised to cut some balsa on the 70mm this weekend, but test flying the Mini Me will have to do. I need to make it to the hobby shop to pick up some balsa and ca kicker.

I`m also going to draw up some basic plans before I get started. But it won`t be long.
Dec 10, 2012, 12:48 AM
3d and EDF, some scale
MustangAce17's Avatar
Getting back on my design since my Phazer is gone, I'm going with a f5d style frame but scratchbuilt, with hotliner wings I've had waiting.
Dec 10, 2012, 04:37 AM
Registered User
evo101's Avatar
this sounds like a great challenge for all!!

im thinking about a HET 1w40 on 7s burst running in a Velocity Mirage 2000
Last edited by evo101; Dec 10, 2012 at 05:01 AM.
Dec 11, 2012, 12:56 AM
imyohero's Avatar
I've been doodling in my note pad and I think I have my design roughed out!

Hope to get cutting on some foam in a day or 2.

This thread really is a great idea, Looking forward to the build!
Dec 11, 2012, 06:56 AM
Aka: Tom Jenkins
ApexAero's Avatar
I do have a question about the temperature and its effects on Doppler, how many mph is affected by 1 degree of temp? or is it really nothing to worry about as long as it gets past 200..personally I think the humidity has way more effect
Dec 11, 2012, 10:16 AM
Lee Liddle
Knife Liddle's Avatar
I'm no Doppler expert but... had RCspeedo set at 90 degrees when it was really 60, and it made my 70mph micro jet read about 110mph. So I'm pretty sure it's important
Dec 11, 2012, 10:18 AM
Lee Liddle
Knife Liddle's Avatar
If you have RCspeedo you can use it on videos and see the difference that changing the temperature makes.
Dec 11, 2012, 10:49 AM
Victim of C.D.O.
murdnunoc's Avatar
With Hyperdyne Doppler's calculations, changing temp by 10F makes a 0.9% difference in speed.

A pass at 70F came up at 164.83mph
and same pass at 80F was 166.38mph.
Dec 11, 2012, 11:58 PM
Aka: Tom Jenkins
ApexAero's Avatar
So, that explains it clearly!
Well Lee is in the lead so far with his 1/2 scale proto type posted, it looks like its doing 203mph sitting still!
Dec 12, 2012, 08:36 PM
Lee Liddle
Knife Liddle's Avatar
Wow! Leading the race and I haven`t even posted a video yet. Yeehaw.
Dec 12, 2012, 08:41 PM
Registered User
LuvEvolution7's Avatar
oh yeah, well, my plane just broke 180 MPH and I don't have a video. am I in the lead now? LOL

oh wait, I haven't even started mine yet. jeeeeez.

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