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Author Topic: new moderator  (Read 8794 times)

Offline bob whitney

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new moderator
« on: June 26, 2015, 08:48:44 AM »


if anyone has noticed ,i have been added as a Moderator for Racing and F2C ,any questions are welcomed .if we cant answer it we will find someone who can Bob Whitney, AMA RAD
rad racer

Offline Bob Heywood

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Re: new moderator
« Reply #1 on: June 26, 2015, 12:12:18 PM »

if anyone has noticed ,i have been added as a Moderator for Racing and F2C ,any questions are welcomed .if we cant answer it we will find someone who can Bob Whitney, AMA RAD

Have Fun...!
"Clockwise Forever..."

Offline Jim Carter

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Re: new moderator
« Reply #2 on: June 26, 2015, 12:16:31 PM »
Congrarulation Bob!  Okay here's my first (probably the only one you won't answer) .... "What do I have to do to beat you in a race"??    LL~ !!  Again, congratulations!!

Jim

Offline bill bischoff

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Re: new moderator
« Reply #3 on: June 26, 2015, 01:25:39 PM »
Finish faster than he did! %^@

Offline BillLee

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Re: new moderator
« Reply #4 on: June 26, 2015, 05:35:37 PM »
Congrarulation Bob!  Okay here's my first (probably the only one you won't answer) .... "What do I have to do to beat you in a race"??    LL~ !!  Again, congratulations!!

Jim

Show up!  ;D
Bill Lee
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Offline bob whitney

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Re: new moderator
« Reply #5 on: June 26, 2015, 07:51:55 PM »


go faster and pit faster  but as Bill says show up . cant believe my pilot is already talking about doing the 1400 again next year  he was sore for 3 days
rad racer

Offline bill bischoff

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Re: new moderator
« Reply #6 on: June 27, 2015, 06:24:57 AM »
Could something like this be done as a NATS unofficial event?

Online Brad LaPointe

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Re: new moderator
« Reply #7 on: June 27, 2015, 07:31:32 AM »
Bob congratulations on your moderator appointment .

Regarding the Brodak 1400 . After being involved with this event for around 10 years that was the closest finish this individual has witnessed.

 Three teams ,sixty pits , not one blown pit . Probably boring to watch but a pleasure to participate in. Congratulations to the teams but mostly to those who sat through light rain to score .

The Toronto crew has a 1400 lapper  set to run in conjunction with the Ringmaster weekend in early October. Super Flys work just fine . The LA .25 needs to be installed forward a bit to get the 24" prop washer to hinge line measurement sorted out .

Running a shutoff will spoil you . It makes the pit man think he's a NASCAR crew chief. We'll sort of .

Brad


Offline bob whitney

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Re: new moderator
« Reply #8 on: June 27, 2015, 01:18:33 PM »


  Brad, it was fun flying with u guys , the pilots had plenty of time to get to know each other ,Dave was having so much fun ,i was having trouble getting his attention to come in to pit .

Bill  it shouldn't be too hard to have the 1400 at the nats  figure between 1 1/2  to 2 hrs per race and two score keepers per plane ,Paul has a sheet made up with the Pit schedule on it for the score keepers to use, which i didn't find out about til the race was over, would have saved me a couple of pits

need to have enough fuel to do 68 to 75 laps per tank
rad racer

Offline Jim Carter

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Re: new moderator
« Reply #9 on: July 30, 2015, 11:03:18 AM »
Bob!  You're a fair man and I respect you, your expertise and your critical evaluative thinking but allow me to put this forth as both a challenge and a true learning issue.  I posted this on another thread but hopefully can you help arrange some sound "scientific"/semi scientific testing to evaluate the question I and a few others have posed.  With your clout and the assistance of the AMA, the AMA can and will provide us with some guidelines, funding and their industry reputation to lead the research.  What I wrote was:

"Truly, I hope you nor anyone else gets angry with me for this but .... why not??  Why not fiddle with line selection especially if the new materials for the lines have been shown to be safe and acceptable??  We fiddle with props, prop construction, airfoils, covering, wheels/tires, fuel, engines, plugs, and even the fit of the handles, right???

So why not the lines?? I mean other than the physical materials of construction, what's the difference in whether one uses 014 with single kink point failure/rejection solids versus 015 stranded or 018 stranded with multiple kinks to failure/rejection and what seems like a much greater pull strength versus 60# or 80# Spiderwire with no kinks to failure/rejection and even greater/snapping pull strength.  Again, please don't bet angry but help me understand the logic and differences or at least point me to someone who can, please.

I mean, unless I misread some postings Spiderwire and similar products are acceptable in fast combat where "destruction is the accepted standard of the sport, isn't it? So why not racing where line contact is essentially nil except in Team Race events??  We're in a whole new century with a myriad of changes in products, manufacturing techniques and quality controls over what was the standard bearers in the "last century", many of which today, clearly outshine the capabilities and safety of "what was" thinking and technology.

All I'm seeking is a sound bit of information based on sound materials testing, use and actual trial versus "that's the way it was and that's the way it will be .... period"!!  I will do all I can to assist and support you should you think this is a realistic and worthy project because I believe it has value across the entire spectrum of the hobby from control line to free flight to r/c.

Offline bob whitney

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Re: new moderator
« Reply #10 on: July 30, 2015, 10:54:35 PM »


 Jim, it is 11:30 as i start this post ,if i don't get it finished i will finish tomorrow.
 
where do we start,there are more than one part to the line size, type of lines, pull test .and so on.
lets start with pull test and get it out of the way, why do we pull test ?? my question is why can we practice all morning then when we get ready for an official , it is an absolute that we get pulled before we fly. why pull test, ?? when we pull test we are testing the complete package from the handle to the bellcrank, we hear all the time about the lead outs  failing on some of the AR F's bellcranks coming out. But what is a fair pulltest my jet speed ship ( 180 MPH ) gets pulled 125lbs . if it pulled that much i couldn't fly it ,But at the NWR the control unit failed at 75 lbs,the wires in the unit started breaking, probably 2 more flights and i would have had a fly a way..a B speed dose 180 and gets pulled 50 or 60 lbs a stunt ship doing 5.2 laps about 50 mph can be pulled over 40 lbs,why?? the reason why is because we are a society where one rule fits all ,we can not take each case individually and this go's for the rest of this post. it is easier for the powers to be to say one shoe fits all

 as for line size ,AMA's  reasoning is that they want the lines big enough that if one line breaks the other line will hold the plane I watched one of Dick Lamberts 150 mph fast rat break a brand new up line. it was in the ground so fast it never had time to transfer the pull to the other line.  if the down line breaks the plane looses pull as it go's over the top.

when i started flying speed 1/2 speed flew on two .08 lines at 100 mph  B speed was on two .012's  now 1/2 a's are on .012's and 21 sport speed which will do about 155 mph are on .018lines.  watch a JR flyer trying to fly  TD .049 on .47 ft .012 lines there is not much chance of him going over 100 mph, but because the open record is over 135 mph he has to be under the same line size rules. again ,one fits all.

 the event that really has a problem with the new line sizes that came out this year are the scale flyers. especially the ones using three line for throttle control  .the lines are so heavy that when the throttle is idled back ,the weight of the lines wants to swing the plane into the circle and they loose control of the throttle,  and this is a plane with a speed limit of about 60 mph. again one size fits all.

Solids vs braided vs spider wire . i have no experience with spider wire other than i know it is used in combat Braided lines are used in the slower DooDaa racing events because they will take the rough treatment better Than solids .that said F2C uses solids but the lines are treated as if they were Gold and replaced at the first sign of a kink. the same can be said for Rat and 1/2A. events like clown also use braided for the same reason rough use

i dont know why anyone would want to use braided lines in speed as they are slower than solids

there was a test done years ago using mono line in speed with a special handle to check the pull. but i cant find any info on it MR Dave Platt Mr Scale has made up a two line handle with a digital scale in it ,as soon as we get the bugs worked out of it we will post our findings

it takes a lot of work to get a safety type rule changed especially when u are backing up, But anyone that wants to go through the trouble and be the front man things can get done

 these  is all my findings and my opinions  Bob Whitney AMA RAD

I know this dosent answer everything but is an idea as to what we are up against
rad racer

Offline Jim Carter

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Re: new moderator
« Reply #11 on: July 31, 2015, 07:37:02 AM »
Thanks Bob!  I really do appreciate you and your most thoughtful response.  Thank you!

Jim

Offline bill bischoff

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Re: new moderator
« Reply #12 on: July 31, 2015, 09:59:19 AM »
I was part of the project to measure actual line pull on models in the early 1990's. What we concluded was that maximum pull measured was about 20% higher that what was calculated. Since pull is proportional to the square of the speed, this probably means that the maximum speed of the model at some point was about 10% higher than the average speed. This is what the calculations in the speed rules are based on.

To calculate pull with the "extra" 20% built in, use the formula Pull =[.08 x weight x MPH x MPH ] / line length in feet.
If you use weight in ounces, the answer is in ounces; if you use weight in pounds, the answer is in pounds.

Without the "extra" 20%, use .0668 as the coefficient rather than .08.

Clear as mud, right?

Offline bob whitney

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Re: new moderator
« Reply #13 on: July 31, 2015, 10:40:11 AM »

thanks Bill, for us dummys what would the pull be on a 60 oz plane at 160 mph ans a 60 oz plane at 50 mph , both on 65 ft lines

Bill, i know we are talking speed here but do u remember what the pull was on any of the ships ??
rad racer

Offline BillLee

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Re: new moderator
« Reply #14 on: July 31, 2015, 12:05:05 PM »
thanks Bill, for us dummys what would the pull be on a 60 oz plane at 160 mph ans a 60 oz plane at 50 mph , both on 65 ft lines

Bill, i know we are talking speed here but do u remember what the pull was on any of the ships ??

See http://www.calctool.org/CALC/phys/newtonian/centrifugal

60 ounces at 160mph on 65' lines = 98.74 lbs

60 ounces at 50mph on 65' lines = 9.64 lbs

CF is a function of the speed squared. I.e., if the speed doubles, the CF quadruples. In your simple example, the ratio of the speeds is 3.2, which squared is 10.24.

98.7 = 9.6 x 10.2
Bill Lee
AMA 20018

Offline bob whitney

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Re: new moderator
« Reply #15 on: July 31, 2015, 12:20:06 PM »

Bill i cant get it to work, what dose   /line length mean. 

it is hard to believe that i could hold on to a plane pulling 98 lbs in a pylon and as we can see the stunters and scale ships are being over pulled  ( again my words )
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Offline Bob Reeves

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Re: new moderator
« Reply #16 on: July 31, 2015, 01:06:40 PM »
LineIII is an update to Pete Soules LineII with updated user interface and a few enhancements. It will calculate the pull on a speed ship accounting for almost every variable. The formula Pete came up with is allot more real life than a simple centrifugal force calculation.

http://www.tulsacl.com/Linelll.html

Offline Brett Buck

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Re: new moderator
« Reply #17 on: July 31, 2015, 02:22:23 PM »
Bill i cant get it to work, what dose   /line length mean. 

it is hard to believe that i could hold on to a plane pulling 98 lbs in a pylon and as we can see the stunters and scale ships are being over pulled  ( again my words )

    "/line length"  is the same a "divided by line length". Absent any aerodynamic effects, the entire equation is

pull = m*v^2/r

where
m - mass (in slugs, take the weight and divide by 32.174)
v^2 - velocity in feet per second squared
r - radius in feet

    Stunt planes are not over-pulled, they are pulled to approximately a factor of 2 margin assuming one line breaks. 10 lbs is about right, by the way.

Proper punctuation/capitalization would make the posts much more readable.

     Brett

Offline bill bischoff

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Re: new moderator
« Reply #18 on: July 31, 2015, 03:17:55 PM »
Is a 60 oz airplane going 160 mph on 65 foot lines a reasonable example? The maximum weight for any speed class is 47 oz, and the line length is 70 ft. (jet and D)

47 oz/70 ft/160 mph is equal to 71.76 lbs (or about 86 lbs with the extra 20% factored in).

Offline dale gleason

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Re: new moderator
« Reply #19 on: July 31, 2015, 11:20:58 PM »
I'm fairly sure that "Spiderwire" is not approved for anything but fishing, unless the manufacturer of "Spiderwire" has a GSUMP* product. "Spectra" fishing line is GSUMP.  If it is GSUMP, it's approved by AMA for combat. No biggie, it's just that some folks are being led to believe that any fishing line is the correct stuff.

dg

Gel spun ultra-high molecular weight polyethylene

Offline bob whitney

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Re: new moderator
« Reply #20 on: August 01, 2015, 08:10:57 AM »


B,B forgot about the 47 oz limate for speed ,was just trying to keep it simple , i am going to get my pull scale out and see what 80 lbs pull feels like
rad racer

Offline Motorman

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Re: new moderator
« Reply #21 on: August 01, 2015, 08:28:13 AM »
Bob, 80 Lbs. is nothing when you factor in the adrenalin surge.


MM

Offline Brett Buck

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Re: new moderator
« Reply #22 on: August 01, 2015, 07:48:45 PM »
Is a 60 oz airplane going 160 mph on 65 foot lines a reasonable example? The maximum weight for any speed class is 47 oz, and the line length is 70 ft. (jet and D)

47 oz/70 ft/160 mph is equal to 71.76 lbs (or about 86 lbs with the extra 20% factored in).

  I think the example was to illustrate how the pull rises faster with velocity than it does with mass, not to be a realistic example.

   I don't know anything about speed flying, but a 47 ounce airplane at 200 mph on 70 foot lines pulls about 112 lbs:

47 oz =2.94 lb = 0.0913 slugs

v =200 mph = 293 ft/sec

r=70

.0913*293^2/70 = ~112 lbs

   How much margin you apply for testing purposes is up to you. You don't want to hear my opinion on that.

    Brett

Offline mike londke

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Re: new moderator
« Reply #23 on: August 02, 2015, 07:31:14 PM »
I'm fairly sure that "Spiderwire" is not approved for anything but fishing, unless the manufacturer of "Spiderwire" has a GSUMP* product. "Spectra" fishing line is GSUMP.  If it is GSUMP, it's approved by AMA for combat. No biggie, it's just that some folks are being led to believe that any fishing line is the correct stuff.

dg

Gel spun ultra-high molecular weight polyethylene
You are quite correct Dale. They are not the same, and lots of people are using the wrong stuff.
AMA 48913  USPA D-19580  NRA Life Member  MI State Record Holder 50 way Freefall Formation Skydive  "Don't let the planet sneak up on you"

Offline Randy Bush

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Re: new moderator
« Reply #24 on: August 03, 2015, 05:34:13 PM »
The four times I witnessed an NCLRA race plane leaving the circle, the cause was an improper launch.  The plane accelerated across the circle and both lines broke -- apparently due to "shock load" when the lines tightened.  In each case the plane continued to accelerate until it hit something solid.  These planes passed pull tests.  I assume the pull test isn't meant to cover that sort of dynamic loading.  Should it be?
In each of those cases no people were on that side of the circle.  The least vulnerable person was the launcher.

Randy

Offline bob whitney

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Re: new moderator
« Reply #25 on: September 08, 2015, 04:10:30 PM »

Randy ,,how u doing?? i don't feel that there is any cure for all that can happen once the plane leaves the ground . i feel that the Dynamic loading is a lot of the reason we are using these over size lines we use today especially in speed.  i had an inverted  21 proto go across the circle on take off and when it hit the end of the lines it snapped my shoulder and it is still messed up today  the lines did not break.  that was with .016 solid  lines .now we are using .018 solid lines because the planes are going a little faster

as long as there is the possibility of law suits i don't see anything changing.
rad racer

Offline Randy Bush

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Re: new moderator
« Reply #26 on: September 08, 2015, 09:49:07 PM »


That's too bad about your shoulder.  The planes I saw leave the circle were both Clowns -- quite a bit lighter than your .21, I imagine.  The lines broke and the plane continued quite a ways. 

I'm doing fine -- in spite of the limited amount of organized racing in Northern California.  Yesterday we had had some "DeweyBird Racing" ( 1cc Norvels on 1/2A one-design profiles). 

Cheers to my racing friends,
Randy

Offline bob whitney

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Re: new moderator
« Reply #27 on: September 09, 2015, 08:11:05 AM »


must be something about those clowns, last plane i saw break loose was a clown at the nats, went over the netting.
rad racer


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