HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Nov 21, 2010, 08:05 AM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
12,799 Posts
Quote:
Originally Posted by Vicarious View Post
Got 2 vids of different X-41 speed passes to check:
On video #1 the top speed was 84 mph

On Video #2 the top speed on pass #1 was ~115mph and the remaining passes were ~108mph.

The problem I am having dopplering both of these videos is from the doppler graphs I see, it appears the model must be diving first then leveling off (can see it in a couple passes) and that is messing with the approaching frequency and puts a bump in the approaching frequency making it hard to pick the correct approaching frequency. This is more apparent on video #2 and accounts for about 5+ mph. So If you want to get a more accurate speed, I would suggest passes with about 2-3 seconds flat and level coming and 2-3 seconds flat and level going away then the readings will be much more reliable

Don
The Don is offline Find More Posts by The Don
RCG Plus Member
Sign up now
to remove ads between posts
Old Nov 27, 2010, 10:56 PM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
20,900 Posts
40mm electrolyte runs.....work your magic don!!!!

about 65 deg. up and down wind passes

6 blade fan

Electrolyte speed pass (1 min 28 sec)
corsair nut is offline Find More Posts by corsair nut
Last edited by corsair nut; Nov 28, 2010 at 12:09 AM.
Reply With Quote
Old Nov 28, 2010, 12:08 AM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
20,900 Posts
and my dons bi3600 powered RCL cougar...

4.25lbs RTF weight...HET fan. 4s 5000.



Corsair Nut's rclander cougar (3 min 3 sec)
corsair nut is offline Find More Posts by corsair nut
Reply With Quote
Old Nov 28, 2010, 09:15 AM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
12,799 Posts
Quote:
Originally Posted by corsair nut View Post
40mm electrolyte runs.....work your magic don!!!!
about 65 deg. up and down wind passes
6 blade fan

I got 74 upwind and 94 downwind, so 84mph average. That was on the first two passes (0:30 and 0:47) the other ones I had trouble seeing as it is quiet and the background/wind noise was not helping.

Don
The Don is offline Find More Posts by The Don
RCG Plus Member
Old Nov 28, 2010, 09:22 AM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
12,799 Posts
Quote:
Originally Posted by corsair nut View Post
and my dons bi3600 powered RCL cougar...
4.25lbs RTF weight...HET fan. 4s 5000.
I got a 100mph and 95 mph, Nice! Once the turbine got into the air it pretty much messed up any readings afterward since he was flying past you when you were coming by the camera. I have two 70mm kits coming I got from Nitroplanes, the Airfireld Mig-15 and the Airfield F-16. I was thinking of trying the BI-3600 in them.

Don
The Don is offline Find More Posts by The Don
RCG Plus Member
Old Nov 28, 2010, 09:29 AM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
20,900 Posts
thanks don!
corsair nut is offline Find More Posts by corsair nut
Reply With Quote
Old Nov 28, 2010, 09:36 AM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
20,900 Posts
couple more electrolyte passes..

Electrolyte doppler pass (0 min 21 sec)
corsair nut is offline Find More Posts by corsair nut
Reply With Quote
Old Nov 28, 2010, 09:43 AM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
12,799 Posts
Those average to about 79mph.

Don
The Don is offline Find More Posts by The Don
RCG Plus Member
Old Nov 28, 2010, 10:09 AM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
20,900 Posts
thanks don!!!
corsair nut is offline Find More Posts by corsair nut
Reply With Quote
Old Nov 28, 2010, 02:18 PM
ΜΟΛΩΝ ΛΑΒΕ
habitforming's Avatar
USA, KY, Hebron
Joined Dec 2005
2,686 Posts
OK let's try this again... now wind noise may be a concern, but hopefully you can get at least one measurement

The clip is edited down, 4 passes back to back with me calling direction AFTER the pass was made

http://www.vimeo.com/17266864
habitforming is offline Find More Posts by habitforming
RCG Plus Member
Old Nov 29, 2010, 12:45 AM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
12,799 Posts
The first two passes were the best, they averaged to 67mph (61mph upwind and 73mph downwind).

Don
The Don is offline Find More Posts by The Don
RCG Plus Member
Old Nov 29, 2010, 07:27 AM
ΜΟΛΩΝ ΛΑΒΕ
habitforming's Avatar
USA, KY, Hebron
Joined Dec 2005
2,686 Posts
Quote:
Originally Posted by The Don View Post
The first two passes were the best, they averaged to 67mph (61mph upwind and 73mph downwind).

Don
Thanks! Not quite what I was hoping for but not shabby either. Btw it was about 40 degrees out, not sure what impact that has?

I think I need to get a newer/higher C battery. Maybe that'll get me into the 70's.
habitforming is offline Find More Posts by habitforming
RCG Plus Member
Last edited by habitforming; Jan 11, 2011 at 11:17 PM.
Reply With Quote
Old Nov 29, 2010, 10:46 AM
Live to ride... and fly!
Tres Wright's Avatar
Forney, TX
Joined Mar 2002
15,165 Posts
Quote:
Originally Posted by habitforming View Post
Thanks! Not quite what I was hoping for but not shabby either. Btw it was about 40 degrees out, not sure what impact that has?

I think I need to get a newer/higher C battery. Maybe that'll get me into the 70's.
You might try an uncut APC prop as well. APC props lose efficiency pretty quickly when they're cut down due to the way they're shaped.
Tres Wright is offline Find More Posts by Tres Wright
Reply With Quote
Old Nov 29, 2010, 11:40 AM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
12,799 Posts
Quote:
Originally Posted by habitforming View Post
Thanks! Not quite what I was hoping for but not shabby either. Btw it was about 40 degrees out, not sure what impact that has?

I think I need to get a newer/higher C battery. Maybe that'll get me into the 70's.
What motor prop setup are you running?
The Don is offline Find More Posts by The Don
RCG Plus Member
Old Nov 29, 2010, 01:13 PM
ΜΟΛΩΝ ΛΑΒΕ
habitforming's Avatar
USA, KY, Hebron
Joined Dec 2005
2,686 Posts
Quote:
Originally Posted by Tres Wright View Post
You might try an uncut APC prop as well. APC props lose efficiency pretty quickly when they're cut down due to the way they're shaped.
Good to know. I've got 2 more props but didn't have them reamed & balanced so I elected to go with what I had that day. I'll do a fresh run next time the weather is good with a new prop.

Quote:
Originally Posted by The Don View Post
What motor prop setup are you running?

Wicked Jr 3200
4.1x4.1 (except it was chipped so trimmed/rebalanced to 3.7x4.1)
Pentium 30
Flightpower 800mAh 20C lipo

I get about 23,000 static RPM, slightly more on a larger 30C battery (~25,000).
habitforming is offline Find More Posts by habitforming
RCG Plus Member
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question could someone doppler this file for me please? pulsar110 Electric Ducted Fan Jet Talk 0 Nov 02, 2009 02:49 AM
Video Can someone Doppler this for me? Bugman Jeff Electric Plane Talk 5 Feb 04, 2008 09:18 PM
Discussion Can somone doppler this for me? CCDR Sabre metroidrc Foamy EDFs 6 Nov 02, 2007 10:28 PM
Video My 650 Watt TwinJet w/ 2X Mega 16/15/3's can someone doppler for me? MailOrderGuy Electric Plane Talk 9 Sep 20, 2007 09:21 AM
Discussion Can someone doppler this for me? Bugman Jeff High Performance 2 May 27, 2007 11:51 PM