How do you verify Park Pilot plane speed?

[Red Scholefield]

With the new AMA Park Fly Program where the limit is 2 lbs and 60 mph how is the speed verified? Winged Shadow Systems www.wingedshadow.com has a neat little device, the HOW FAST ($44.95) that does the job. The 2.7 gram unit, plugs into your receiver and includes Pitot and static probes that mount on the wing. Maybe a good item for clubs to consider.

[fhhuber506771]

Very good question...

There is no really good answer.

You can get a good estimate of what YOUR small field model can do...

Motor KV * battery nominal voltage * prop pitch.... toss in a conversion factor and you can get MPH that the prop is trying to pull the plane forward.

"Sleek" designs can approach actually hitting this theoretical speed... might actually exceed it in some cases.

If the power system is reasonably efficient for the plane... the level full throttle speed should be no less than (theoretical)/1.5

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Most people will not want to pay for the "How Fast" device... and its accompaning "See How".... That cost might exceed what their plane cost.

***********

There is a doppler program you can download FREE...

Then record the sound of your model doing a high speed pass over the tape recorder.... Convert that to a WAV file... feed that to the program and you can get a very good reading.

(now where did I hide that webside link? Its in german... has a ".de" in it The program has english (enough to understand what its doing) )

[abel pranger]

Two markers (traffic cones, painted lines, etc) 176 feet apart on the edge of the runway. If the model traverses the distance in less than two seconds, it is in excess of 60 mph. More than two seconds, it is within the PPP limit.

Abel

[Murocflyer]

Two markers (traffic cones, painted lines, etc) 176 feet apart on the edge of the runway. If the model traverses the distance in less than two seconds, it is in excess of 60 mph. More than two seconds, it is within the PPP limit.

Abel

Well that is certainly easy enough. Solid and reliable.

Now where did I put those traffic cones :confused:

Frank

[abel pranger]

While you are looking for the traffic cones, keep an eye out for the little sand filled vial used to time one-minute eggs, too.

[OnVacation]

With the new AMA Park Fly Program where the limit is 2 lbs and 60 mph how is the speed verified? Winged Shadow Systems www.wingedshadow.com has a neat little device, the HOW FAST ($44.95) that does the job. The 2.7 gram unit, plugs into your receiver and includes Pitot and static probes that mount on the wing. Maybe a good item for clubs to consider.
With the faster electrics, its just one more reason to not have tiered criteria.
What about the 2.01lb plane that was going 61mph? There will be a lot of those, in reality.

Bill

[fhhuber506771]

With the faster electrics, its just one more reason to not have tiered criteria.
What about the 2.01lb plane that was going 61mph? There will be a lot of those, in reality.

Bill

A good example of why the PPP wasn't well thought out.

[typicalaimster]

With the faster electrics, its just one more reason to not have tiered criteria.
What about the 2.01lb plane that was going 61mph? There will be a lot of those, in reality.

I was going to say, with the exception of the hotliner race planes.. How many foamies have you seen going over 60mph? I have a AeroCat and I hardly doubt it's going even near 60mph. It may look like it, but doubtful.

[fhhuber506771]

Ever flown a .19 powered CL stunt model? "The Ringmaster" for example... on 60 ft lines (actually 55 ft, but add arm length and half the wingspan and you are at 60 ft radius) is doing 55 mph when it takes 5 sec per lap... and its easy to do a 4 sec lap...

Having flown those style planes a lot... (and faster CL planes) gives a pretty good feel for how fast a model is flying just by watching it fly by appx 60 ft away...

Its pretty easy to exceed 60 mph with a model... My Hobbico Superstar EP ( a "park flyer" trainer) can do it... The Park Zone Typhoon can do it with just a prop change. The Parkzone Stryker F27C does it easilly.

All are under 2 lbs... all are marketed as park flyers.

[Charley38]

Two markers (traffic cones, painted lines, etc) 176 feet apart on the edge of the runway. If the model traverses the distance in less than two seconds, it is in excess of 60 mph. More than two seconds, it is within the PPP limit.
Abel

Speaking as someone who used to do measurements of this nature in the field professionally; I have to say: it ain't that easy. First, you have to bracket in time when the model crosses each line. If you use people with flags or switches, you have to figure in reaction times, which are variables. Then there's wind speed and direction. Then there's .... Like I said it ain't that easy. ;) :)

CR

[lowdive]

rough estimation is all that's needed. like you won't get pulled over doing 68mph in a 65mph zone... since i do fly a modified stryker that easily exceeds 60, as do a few of my other models, i got the open membership. if someone is concerned enough to get membership they will pick what is appropriate for what they are flying. if not, they aren't covered when they hit someone at 61mph with a 2.01lb plane. i'm sure it's a lesson they would not forget.

i speak from experience. i'd blow off AMA membership if i hadn't nailed the windshield of a ford expedition with my stryker. it left a softball sized crater and filled the inside with bits of safety glass... at a little league baseball game.

sometimes it takes an idiot moment to open your eyes.

[aeronuts]

...they aren't covered when they hit someone at 61mph with a 2.01lb plane...
Of course after the massive collision, there will be at least .01lbs missing when you gather up the pieces. And if nobody had a radar gun on it... :rolleyes:

Some of these things the AMA thinks up...

[mongo]

...

[aeronuts]

man aeronuts, don't you watch CSI on tv? the investigators and coroners can piece together the actual weight and speed of the aircraft just from the impact wound on the body. they do it every week in the shows.
<HAHAHAHAHAHAA>
Oh, that's right. I forgot about all that high-speed fictional technology that can be used to solve any crime, no matter how complex, in less that 60 minutes (with commercial breaks of course). :p

[Charley38]

i speak from experience. i'd blow off AMA membership if i hadn't nailed the windshield of a ford expedition with my stryker. it left a softball sized crater and filled the inside with bits of safety glass... at a little league baseball game.

sometimes it takes an idiot moment to open your eyes.

And it takes an idiot to fly an RC model at a little league baseball game. What the hell were you thinking?

CR

[lowdive]

i did say it was an idiot moment, did i not? it is not something i would do again and would keep others from doing. i've learned. judge me on that and perhaps you'll find i'm not a bad guy. no need to attack me.

[aeronuts]

And it takes an idiot to fly an RC model at a little league baseball game. What the hell were you thinking?

CR
Well, at least the crash was in the parking lot and not on the field. :eek:

Give the guy a break. He shares a moment that he openly admits involved a lapse in judgment, in hopes that others may learn from it. I appreciate his honesty. No need to chastise him for it further.

[fhhuber506771]

Learn from my scars...

so you might not get similar ones...

[lowdive]

well, i did hit myself with my plane last saturday so at least i've taken the public factor out. thanks.

[Charley38]

i did say it was an idiot moment, did i not? it is not something i would do again and would keep others from doing. i've learned. judge me on that and perhaps you'll find i'm not a bad guy. no need to attack me.

OK, maybe that was a knee-jerk reaction. I'd love to fly my parkies at the local park but there are always people around. Glad you know better now.

CR