F3A Zone Pro

When you are practicing aerobatics (or setting up a competition site) there is no really good way of setting up some box markers to identify the F3A ‘box’. Most often you will see someone kneeling on the ground with a sighting board moving about on top of a transmitter case, with some guys guessing where 150m may be (and its usually a big guess), and trying to position the box marker poles. There is lots of arm waving and phone calling to sort out where they should be placed.

Being a keen F3A pilot, I have come up with something of a solution to these problems – F3A Zone.

There are both iPhone and Android versions of the app - if you both are using 'F3A Zone Pro', you can freely email and view boxes created on either device - really useful when there are 3 people at the field with different devices - now one person can setup a box, and email to the others regardless of device type, and you go and set up a pole each, while viewing the exact same box!

Usage:

First the limitations: The app uses GPS, which has ‘variable’ accuracy. This app is a superb way of getting all 3 box markers at 150m (plus/minus a few meters) – in fact, it is the only practical way of doing this. As far as the 60 degree box angle goes, I have found the GPS positions to be at least as accurate and reproducible as a sighting board. I would be interested to hear how you get on! Remember, you can always use a sighting board to confirm the angles, knowing at least all 3 poles are at 150m.

You only need to follow a few simple steps:

1. Select how far out you want the poles positioned - typically 150m out from the pilot – other distance options are there if you have a river, etc in your way!

2. On the next screen, wait for GPS to be acquired.

3. Stand where the pilot will stand and hit 'pilot position'

4. Walk directly toward center - at least 10m - and for best accuracy a bit further like 50m or more and hit 'on the way to center'. The further you walk here the better – this is important.

5. Now select 'draw box'. The box marker positions are drawn on the map, along with lines joining these to the pilot position.

6. Now walk toward where the first box marker needs to go. You can zoom in on the map as you get close to the box pole positions, and locate them really accurately. Zoom back out as you head to the next marker position.

Notes:

The positioning relies on GPS - this app is about the only practical way to position all 3 poles at 150m. In our experience, we would say the 60 degree box angles are more reproducible with this app than a sighting board wobbling on a transmitter case. But check these angles till you have confidence in the app at your location.

You can of course 'save the box' - saved boxes can be retrieved at a later date to set up exactly the same site again. Saved boxes can also be emailed to other users of F3A Zone Pro - either iPhone or Android.

Remember, the app uses GPS – so it is not accurate enough to use to mark a ‘close in box’ at the far edge of the strip for practicing. It is good for marking out a box at 150m.