Hello,

Interested in trying some GPS testing for practice. Looking for info like distance out, altitude, speed primarily. What has worked well for others? How useful is this data for you pattern practice?

Looking at this

http://www.towerhobbies.com/products...cap0338_e.html


curious what else is available.

I have found the GPS data very helpful. The most difficult thing to do well is fly on the right heading at the right distance while performing maneuvers. First I set up my GPS to announce heading every few seconds while practicing big square rectangles. After awhile you get to know what the plane looks like when it is on the correct heading and pretty soon you get to trust the airplane and stop putting in corrections it doesn't need. I found I had been making the same mistakes over and over. I don't believe heading info would help during a contest as there is a lag. I also used the GPS data to tell me how well I was staying in the box and keeping the plane between 150 and 250 meters out. You can't do this in real time as the distance to the plane is constantly changing even if you fly exactly parallel to the runway. I don't think taking a reading when you get to the centerline would be too accurate either because of the lag and the variance in altitude. So I plot the path of the flight on the computer, usually after I go home. I think everyone would be surprised at how far out most folks fly. Again you can see how you do the same thing over and over with the same errors, pilot induced, based on the wrong perception of the flight path. Of course there are other functions, too many to discuss, that telemetering can provide, but I believe practicing with the GPS is very valuable for perfecting pattern flying.

It doesn't look like the unit you are looking at would be that much help. I use the Jeti RC system which is very well integrated so all I need to do is plug the GPS unit into the receiver. To use it with a different system you would need the GPS, a Jeti receiver and a Jeti Profi Box to receive and record the data on the ground. You can check this stuff out at Esprit Models web site.

Jim O

I know some guys have used the Eagle Tree setup with some success. I've never used it, but heard good things from those who have.

Arch

Hi Anthony,

I actually flew that one in my Mythos last year a bunch during testing and it was very cool to see all of the info. A Velcro strap around the wing tube and it never moved.

Distance and the mapping over on Google earth made it really neat to be able to see where I was flying in reference to where I was standing and able to check my distance as well as to see thta I was flying a straight line.

Hope this helps,
Dan

Jim O and Dan,

When you display the flight can you control the speed the data is displayed so you get an idea of when a deviation occurred?

Is the output controllable like a video tape e.g. can you stop/ resume, replay and go back to a specified time?



J e r

Yes, in the attached photo you can see the flight path of the plane superimposed on the overlay of the "Box". You can move the small airplane on the bottom as fast or as slow as you want to go through the pattern and see how you are doing. I have it stopped shortly after takeoff.

Jim O

It's great to get a digital readout and all with GPS. But a lower-tech option for feedback on ground reference/box position, etc. I have used a rear-facing keychain camera like in this clip (tape & velcroed just behind the canopy) and cross-reference it with known landmarks in Google Earth. This method also wings-level readouts - which you don't get w/GPS alone. Cheers, Bill

Pretty neat. Do you have photos of the camera and its installation?

Jim O

With the jeti transmitter and the GPS unit I can tell real time what heading I am on , and set alarms to tell me of I am moving out or in.

griff, that is awesome.

OhD, I'll see if I have a photo. If not, it's a #18 keychain camera with a bit of velcro on the back, velcroed onto a velcro pad glued right behind the canopy latch. The velcro is just for making sure I don't lose the camera. I tape it in position (aiming is critical) with a couple of strips of painter's tape over the top.

Sounds like it might be better than a continuos voice repeating the heading. I assume you can select one pair of alarms for going right to left and another set for left to right? Where do you set the alarms, plus and minus 5 degrees or tighter?

Jim O

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One question griff, that's heading and not track, right (track=course over the ground, wind-corrected)? If heading and not track, do you wind-correct in your alarm settings?

The GPS is plotting a point moving over the earth. It doesn't know it is an airplane. I guess that is what you call track.

Jim O

I want to point out that you don't need to fly a Jeti RC system to use the Jeti MGPS that records the flight path of your airplane. All the MGPS needs is power so all you would need to do is connect it to one of your receiver ports. After flying you would need a Jeti USB adapter and a free Jeti software program to download the data to your computer. You can then display it in an online program GPS Visualizer. You can display it in Google Maps or Google earth. I'm not sure all the capabilities such as looking at a specific maneuver during a flight but I hope to learn more. I've attached a bird's eye view of one of this weeks flights.

Remember, if you don't measure anything, you can't improve on it. The downside of that, is it is very humbling and discouraging to see your flight path.

Jim O

Jim, finally found a photo of my hi tech installation of the keychain camera: tape & velcro