rcproptester

Not that I am advocating breaking the rules, but.... 200+ is cool

Liquidity

BVM sells a ducted fan that flys at 175mph with easy mods to over 200. http://www.bvmjets.com/Pages/kits/electra.html. My buddy is the new owner of one. Jeff, check your voicemail/txt messages on your phone.

rcproptester

check your PM Bryan

Larry3215

In this case 'easy' = $$$$

All it takes is money and you can go as fast as you want The 150 mph version is going to cost you $4500 plus to get it off the ground at a minimum.

I like the 100, 125, 150, 175, 200 break downs better.

The difference between 100 and 125 doesnt sound like much in terms of speed but its a LOT in dollars. The price for each additional 25 mph keeps getting higher as you go.

Based on some calcs by TheDon on his Lynx, it takes about 400 watts to hit 116mph. To get to 130 mph we will need 560+ watts. 150mph will need 865+ watts!!!

Thats assuming you can physically fit the larger power system into the Lynx - which in the case of the Lynx you cant fit much more than a 500 watt setup because of space restrictions.

To break 150 mph will take a larger model just to carry the larger packs needed to generate the power you will need, A larger model which probably has more drag and weight so your going to need even more power

Larry

rcproptester

Just for giggles I hooked up a 5s 4350 pack to my lynx with the don's outrunner. I hit 700 watts at just over 1/2 throttle, and got scared and cut it off... If I had tried to use it however, I would have had to cut the nose off my lynx and use the battery as the fuselage!!

CHELLIE

Sounds great I was Talking with Kosh and we were trying to think of a way to have a chart /form on this thread, as a membership into the 100mph club, so that people could enter there user name, speed, date of achiving a speed run above 100mph, model type, and a link or type in a post number showing a doppler reading and a video as proof of there achivement, myself I and not all that computer savie, so If anyone knows of a way of doing this, please give your suggestions, and I am sure Mike will know if it will work or not here, I know for sure that, there are a lot of Great Minds out there Sooo I think a little Brain Storming, with the Membership will help in getting something on the board, Take care, Chellie

CHELLIE

go for it

ShutterAce

Gee, now you people got me all excited here. And I haven't even started on my supersonic amateur rocket! Way too many fun projects on my list but I can always use another and this sounds like it.


BTW I like the first award an the 25mph breakdowns.

CHELLIE

Welcome to the ADDICTION JIM

Larry3215

I just realised - now I have to build something that will go fast!

Darn it I have toooooo many projecs going as it is!



Larry

P.S. Chellie - did you get any more runs in today?

CHELLIE

Hi Larry, going to get some runs in tomorrow, there was no one at the flying field today to help me do the videos, so Tomorrow there should be some warm bodys around Take care, Chellie

Larry3215

What? You cant fly the plane and run the cam at the same time

Larry

CHELLIE

Hi Everyone, here is another attempt, I changed the prop to a apc 5.1x 4.5 thin prop, the Field was Kind of noisy, cars, planes But maybe someone can get a doppler reading from what I have, Please Excuse the bad Landing Nothing Hurt But my Pride , Got to love that EPP Foam ,I think I might need to go to a 4 cell Lipo, I was trying to do it with a 3 cell, but I dont think thats going to happen Enjoy, Chellie

FlyWheel

While the AMA does, I believe set a 200-MPH speed limit, I think that only applies to everyday flying, not sanctioned or supervised events. Otherwise, how could we have a 301 MPH record?

Any speed reached at such an event would also have an undisputable official record of the actual speed, One which is going to be much more accurate than a doppler taken from a U-tube video clip posted on a newsgroup forum (can your audio doppler programs be fooled by savvy throttle handling? Just wondering).

I still think special recognition should be awarded to the first WattFlyer to break 200.

Larry3215

Hi Chellie,

The fastest run I could find was reading about 80mph. Allowing for how far away from the camera you were (Id bet Kosh was laughing! ) Id say you were mabey as much as 85mph peak.

Yeah, you need MORE POWER

Larry

CHELLIE

Thank you Larry Thats what I thought, 1 more cell should do it
and drop down a little in prop size, even 80+ MPH had my blood boiling
Take care and have fun, Chellie

Larry3215

Yeah, one more cell and reduce the diameter of the prop but keep the pitch the same. That should boost the rpm a good bit

Larry

P.S. Next time - lower and closer in! Make that camera man flinch!

CHELLIE

OK, but the Camera man is standing right next to ME .

jeholliday

Chellie, that approach you was making for the landing is what you need for the timing of the speed, but, keep it level. That wing does look a little ustable for speed trials. At our field years ago one of the guys who was on local police force and had radar gun with him. Amazing how slow the gun said the plane was flying when we ourselves thought it was much faster. Another thing was the guys that got flutter when they made their dive towards the runway. We were lucky that only one plane went in, but, none of them exceeded 100 mph. Thought about building a special plane for the next time like Bob Violets FAI pylon plane of years ago. But, I got faith in you girl, go do it. DOC Holliday

shotgunsmitty

I kinda like the idea of 25mph breakdowns of speed, too. I don't advocate giving awards away without earning them, but if you make the effort and qualify, then sure.

Larry3215

Chellie,

Another thing to do for speed runs is to try to reduce drag. Look for anythng on the plane that might be causeing drag - loose covering, seems or joints, seal the hinge line, streamline hatches or covers and make them fit tight, no hanging antena wires etc.

Thngs like that will help a lot more the faster you go.

Larry

Larry3215

oh - and balance the prop with extra care. See if you can get it running butter smoooooth

Larry

CHELLIE

Thank you Guys If I cant Do it with this plane, Then I am thinking about getting a LYNX XF and 4 cells Take care, Chellie

gzsfrk

Just out of curiosity, does it strike anyone else that perhaps "flagging" everyone who's flown their electrics in excess of 100mph would be like placing a bullseye target on them for the feds? I'm not sure, but I would think that even a foamie flying at 100+ mph could kill someone, particularly if the prop is on the front.

Are there any legal ramifications for flying electrics at high speed? I mean, I know there would be legal issues if you hit someone (assault & battery, etc. etc.), but what if some authority figure simply saw you flying that fast? Could you get in trouble? Would you have to be in a certain type of area, or possibly even licensed at some level?

Liquidity

Iam running the dopler now. I just got back from the field. Here is the data.

Lynx
Dons Wicked motor
4s2100 25C lipo
70A ESC
5x5 APC E prop.

48A (Yes I know the motor is not rated for anything close to that)
615W (AWESOME AWESOME AWESOME)

Ok back to Dopplering.