Measuring the Speed of an RC Plane

[TheHAndyRC]

HI there, great video :)

Just one question though, how do you know which curve in the audio program to pick ? It looks like there are a load of different size ones

[RCB0B]

Holy SH!T that plane is fast!!!! 0_0

[DJPettyv4]

Good job!

Its interesting how the air speed and the ground speed are so different. I always did wonder how they checked the air speed. Now I know.

[davereap]

interesting..I will have to give that doppler method a go... dave

[Gezelem2002]

Very informative information. I wondering how the Doppler effect works. Thanks for sharing. Also I figured you guys were having around 24mph winds that day..... Nice 5*

[rcFoamFighters]

Thanks Gezelem2002! The wind may have been around 24mph. That same day I did use my wind meter and it was revealing gusts as high as 20mph on the ground. May have been a little stronger up in the air. Thanks for watching!

[BRANDORC]

suweet, finally figured out how to pull audio from my wma files and create a wav file for the scope program. the ugly wing is running just over 70mph. not too bad for a smaller power setup and a big prop.

[rcFoamFighters]

Hey Brando, Cool glad you got it figured out! 70mph, not bad for the wing. I'm sure you'll smash that numebr with your new crazy speed plane!

[rcmotorsect]

144mph, thats pretty fast! almost as fast as the funjet! doppler has always confused me, but this vid helped me understand it! never really got speed from sound phisics, and you would proubly want the peto tube on the side, or the vertical stabilizer, because they are very delicate, bent in the first hit on the grass, cant wait to see what you'll come up with next!

Thanks,

Ben

[rcFoamFighters]

Thanks rcmotorsect! Yep , pretty close to teh funjet. I think this plane has a bit more drag as it is biger and has a thicker wing. Its lots of fun though still. I may try some other places for teh pitot tube, but most likely will leave it in the nose for the most acurate reading. its best to keep it in totally clean air undisturbed by other parts of the plane. Thanks!

[wildhover]

great info Paul. you sent me this program about a year ago and i could never figure it out (that's because the zip file never included the actual WaveosScope program in it, just the instructions and mig sound file). so i went to the website and downloaded it. you just gave me a new toy to mess around with- wooohooo!

[rcFoamFighters]

Hey Ken, haa ha, sorry didn't know we didn't send you the correct files. Hope you got it figured out now. Thanks for the comment. Can't wait to see mor of your FF-15! Take it easy my Filipino Brother!

[MclF01]

233KPh wow man thats quick zoooooooooooooooooommmmmmmm!!!­!!!!!!!!!!!!!!!!!

[rcFoamFighters]

Thanks McIF01! Zoom Zoom Zoom! Thanks for watching!

[MartijndeGraaf1001]

so windspeed would have been 143-119=24 miles/hour

[rcFoamFighters]

MartijndeGraaff1001, pretty good deduction I would say. I was pondering the same thoughts when out at the field. I did have a small wind meter that day and it was measuring gusts up to 20mph that day. So it may be close. Also my pitot tube may still not be in the best place. Once I mount it properly it should be more accurate. Thanks for your comment!

[zyoungson]

Wow, very informative!! thanks

[rcFoamFighters]

Thanks for watchin zyoungson! Glad it was informative for you.

[bakerrv]

Thanks for the explanation on the Doppler program, I got about the same speed as you did. It really matters where you measure, it is only as accurate as where you measure the line, right, left or in the middle of the line. Cool stuff!!! Thanks

jb:^)

[rcFoamFighters]

Thanks bakerrv! You are very correct, the program is a little subjective to where you mark the lines. I think if you mark pretty close to the wave lines it should be fairly close, within plus or minus 5 miles an hour. Again this is going to give you a relative speed and not a deas on accurate speed. Thanks again!

[startazz]

Man 143mph is moving some for sure but i don't think i would be able to control my nerves at that sort of speed and i'd deck it lol,great info on all the speed test we can use if we so wish,so thanks for the great work and all the info you boys share with us all = 5

[rcFoamFighters]

Thanks Ian! Haa haa, I hope you wouldn't Deck it. Actually the SuperNova is one jet I feel real pretty relaxed and confident when flying, even at high speeds. This jet is by far the most stable and predicatble design I have made to date. Thanks for watching startazz!

[fathead431]

awesome! very cool software! im gonna use that for my cars boats and planes. ill see if its accurate! thank you very much 5/5

[rcFoamFighters]

Thank fathead431! Cool, that would be neat to see the program used in different applications as you mentioned. Please let us know if you do. Good Luck with it!

[MrROTD]

Wow a pitot tube that's high tech!

[rcFoamFighters]

Thanks MrROTD! Haa haa, think I ruined teh High Tech look with my ugly tape mounting, LOL . Oh well,i can mount it better later. thanks again for watching!

[MrROTD]

Yeah you could mount it so it's not so ugly lol

[cslr11]

great video . you gave a lot of great info .

[rcFoamFighters]

Thanks cslr11! Glad you found the video useful. Thanks for watching!

[bobsiopener]

It shouldn't matter if the camera is panned with the plane, the pitch is only changed with the relative speed not the angle you are facing. If you turned around you would still hear the Doppler effect. It does matter the angle the plane is flying in relation to the camera man.

[rcFoamFighters]

Thanks for the comment bobsiopener. You can still get good sound readings whan the camera is panned, but I have noticed that iff you do not pan the camera you get cleaner, single step wave forms. The more steps as and alterations in the sound form distorts your reading. Sound waves can bounce, reflect and change even slightly by changing the position of the microphone. It is my opinion but I think keeping your microphone sationary will give the best results. Thanks for your comment and watching!

[pudd750]

GPS MPH info would be dead on but a micro camera would need to be aimed at the MPH section on the screen on an onboard GPS-- soon someone will come out with a GPS for RC with remote readout

[Galilee1986]

It's already exist. Check eagle tree web site with the on screndisplay a wireless cam and the GPS expender. You can have a virtual Hub for an RC airplane. Alittude, speed, battery, and more !

[rcFoamFighters]

Thanks Galilee1986 for answering Pudd750. I do want to get the full eagletree set up with GPS eventually. Would be real cool and the most accurate. it records the whole flight too.

[rcFoamFighters]

True Pudd750. See Galilee1986's response below. eagletree does make a GPS module, I hope to get one in the future.

[pudd750]

frikkin bullet would go thru a body part without passing go, collecting $200, etc

[rcFoamFighters]

thanks Pudd750 for watching. Yes a 143mph 3 pound missle would leave quite a mark... This is why we are starting to use the WaveosScope program and Airspeed module more. the Radar gun is becoming increasingly dangerous..

[johndog35]

Great video, I have been trying to compair these. You way is the easiest for me. Since I dont have any suckers to hold the Radar gun I think the doplar is going to work for me.

[rcFoamFighters]

Thanks johndog35! Let us know how your speed readings come out. If you use the WaveosScope program just read the english instructions and you should be good to go. Good luck and thanks for watching!

[mudman1959]

Paul... I also recommend mounting the probe on the leading edge of the wing about 2 inches from the fuselage, or along the side of the fuselage about a half inch off the side. This should protect the probe from damage occurred during landings... Mudman1959

[rcFoamFighters]

Mudman1959, another good point. I thought about wing mounting, but i wanted to make sure it will be in a clean airstream. Any deflections off the fuselage can give abnormal readings. I am not super worried about the tube in the nose, as eagle tree sells standalone pitot tubes. Also good for mounting in several planes.

[mudman1959]

Airspeed is not only just pitot pressure but also static pressure (altitude) that is wht there is two tubes coming from the probe and a small hole in the side of the probe. The higher you fly, the higher the airspeed... which by the way is measured in knots. Look at your wavo-o-scope knot reading it showed 125 Kts. which was close to the reading from the probe readout. Also the barometric pressure plays into the game. Good video! Mudman1959

[rcFoamFighters]

Thanks for the comment Mudman1959. Your point about static pressure is a good one. That is what I was meaning to say when I said "Ambient Conditions". Thanks for clearing it up. As for the module, Eagle Tree's website and instructions say the read out is in MPH and not Knots. It can also be set to KPH by using a jumper in the plug. Please see their website, link is in the sidebar.

[Eugensdiet]

Great video. I wasn't aware they were doing Doppler effect. I wonder if I don't have a couple videos that I could check. I fly a lot of small planes and the Doppler method should work fine. They are to small for pitot and probably to small for radar. Be careful guys.

[rcFoamFighters]

Thanks Eugensdiet! Cool, hopefully you do have some videos that can be used to test your planes. Hope it works out for you, good luck!

[savageZA76]

The tube for measuring the speed, is maybe not so practical, because when you have a small crash, that the plane can surely take, you will wipeout that speed tube.

[rcFoamFighters]

Thanks for the comment savageZA76. With the tube at teh ver front it mag get damaged easier. It can be placed on the wing or other places, though the nose is the best place to get clean airflow and accurate readings. Eagle tree does sell the Pitot tubes seperately also incase you damage one or want to put them in several planes. Thanks again!

[jacquesone100]

Cool vid guys!..good info!!... cool to know how the Wavescope program really works!.. think i need to do some more good runs :)

Great stuff !

Jacques

[rcFoamFighters]

Thanks Bro! Yeah I hope that helped show how the WaveosScope program works a little. It is most important to get good clean sound files to be accurate. Rock On Jacques! Can't wait to see more of your crazy speed plane!

[rowdyrodcumming]

Hey Paul, excellent video... I've been meaning to work out how the doppler software works and you explain it perfectly. Nice comparison, thanks!!

[rcFoamFighters]

Thansk RowdyRod! Cool, I'd love to see how fast your planes are too! Keep on flying !

[FlyHighRC386]

wow this is a very beneficial video paul, im sure this will help many RCers as well as my self explore this. Great video. 5* that module looks really cool.

[rcFoamFighters]

Hey Mikey, Thanks for the comment! Hope all id good for you in the UK. When do we get to see some of your FPV footage? Hope soon. Thanks again for the comment!