I often get questions about programming routes and how I set up my instrument for competition flying, this usually happens at briefing just before takeoff, when I want to get ready to fly and have no time to go through the setup with someone new to the instrument. Sorry I could not help you guys at takeoff, but here’s the guide to use before the next comp.
Hint: It’s a lot better to do this at home before flying, where you get to know the instrument a bit better, than in the stress of setting up and getting ready to fly the first task of the nationals, or worlds…
I do not write about route programming here, I can do that if you find this useful – leave a comment.
General setup
I have software version 3.28 in my Compeo+, if you have an older version you might not get all the fields I have described here. Upgrading the instrument is not difficult, but not for the complete computer novice either. (I can do it for you, after flying)
There are three pages in the instrument, accurately named P1, P2, and P3 in the top middle of the instrument screen.
I have three fields that I keep the same info on all pages; it’s the upper right field that shows distance to active waypoint, and the upper and middle left fields that show Wind speed and groundspeed. These three are the basic information that always changes during the flight, and if you keep them in the same place it’s easier to read the instrument quickly and accurately.
The reason I lay out the fields like that is to have a natural way of scanning the display, like reading a page top left to bottom right; Starting with the Vario/McReady – course arrow – airspeed/height/distance to TP, next line down – ground and wind speed, and then the variable fields.
You change between the screens in flight by pressing right arrow button.
Page 1 – Startgate
The most important thing when you are flying and waiting for the startgate is to be aware what time the start gate is, and how far it is to cross the cylinder so you can time the start perfectly. It’s also the time to get a feel for the thermals and conditions, so it’s a good idea to note the wind direction and strength.
Left side fields, from top.
Wnd Spd – Windspeed – Shows a calculated wind speed. This value is calculated from the difference between airspeed and groundspeed, so there is a big margin for error, consider it an estimate.
Gnd Spd – Groundspeed – Shows your groundspeed from the GPS.
Time – The clock from GPS – Shows the time your GPS is logging. If this time is wrong you need to change the UTC offset in the setup menu. (Typically when daylight savings change or you travel to another time zone)
Also note that you will have a countdown timer to the first startgate in the bottom of the screen when you have activated the competition route.
Right side fields, from top
Dist WP – Distance to center of active waypoint – This will show the distance to the center of the startgate cylinder, not very useful for now.
Cyl Arrival – Estimated arrival at cylinder. This shows the estimated time when you will cross the cylinder when you are gliding towards the cylinder. I usually calculate 1 minute per kilometer, which is 60 km/h groundspeed. This field is a “nice to have” as it confirms what you have estimated in your head.
Dist StCyl – Distance to start cylinder. Very important and useful, shows how far you are from the start cylinder edge. Combine with the countdown clock in the bottom of the screen to calculate when you need to start gliding to take an optimal start.
Dist Toff – Distance to takeoff point. Useful if you have to glide back for a restart in Aerotow competitions, otherwise useful for open distance flights.
Page 2 – On course
During the task you want to know how far it is to the next PT, to plan ahead and find the fastest route there. I do not fly with a mapping GPS, (Just look down for an updated map) so I rely on memory and the cross track information to know where I am in relation to the course and next TP. Having updated windstrength and direction is also nice.
Left side fields, from top.
Wnd Spd – Windspeed – Shows a calculated wind speed. This is calculated from the difference between airspeed and groundspeed, so there is a big margin for error, consider it an estimate.
Gnd Spd – Groundspeed – Shows your groundspeed from the GPS.
Dist goal – Remaining distance of the task. Very nice to know if the goal is close to the last TP so you can start the final glide before that last TP. Also nice morale booster/destroyer depending on how your flights are progressing.
Right side fields, from top.
Dist WP – Distance to center of active waypoint – This will show the distance to the center of the next TP. Usually we have 400 meter radius, but sometimes there might be a 1000m or more radius for special cases. See the lower right field for distance to cylinder, but this is still nice if you forgot to set the right radius in the route (Been there, done that), as it will show you when you are close enough.
XT Error – Cross track error. This is very nice when flying crosswind tasks; it shows how many km you are off track. Minus is left of track, no minus is right.
Alt a WP – Altitude above WP. This is a glide estimate, showing how high you will arrive above the next TP if you glide for it now. I use it as a confirmation that I am where I think I am relative to the TP and wind.
Dist Cyl – Distance to Cylinder. Shows the distance to the cylinder of the next TP. Very useful if there are varying cylinder sizes in the task.
Page 3 – Final glide
Having made it here it’s all about the glide, so the setup changes to focus on glide angles.
Left side fields, from top.
Wnd Spd – Windspeed – Shows a calculated wind speed. This is calculated from the difference between airspeed and groundspeed, so there is a big margin for error, consider it an estimate.
Gnd Spd – Groundspeed – Shows your groundspeed from the GPS.
L/D gnd – Glide angle over ground. This shows what your glide over ground is in the moment, somewhat useful to get an idea of your glide, but it varies a lot and is not a good indication if you will make it or not. See the L/D Goal for that.
Right side fields, from top.
Dist WP – Distance to center of active waypoint (Goal). Again this is the center of goal TP, very useful if there is a goal line.
L/D Goal – Glide angle to goal. This shows the angle from where you are and to goal. The most useful function on the final glide! If you are on glide, and the number goes down (From 15:1 to 14:1) you are gliding well and should make it in unless conditions change (Or you speed up too much). If the number goes up (From 12:1 to 15:1) you will not make it and need to look for more lift, more tailwind, or a miracle :-)
Alt a goal – Altitude above goal. This shows the estimated altitude you will arrive over goal if you do an optimal speed glide to goal. (Calculated from the polar you have programmed in the instrument) This number takes wind speed and direction into calculation.
Alt a BG – Altitude above best glide. This shows the estimated altitude you will arrive over goal if you do a best glide to goal. (Slow glides keeping the speed at best glide all the way in) This number takes wind speed and direction into calculation.
Remember;
- All the glide functions require that the goal waypoint has the correct altitude, and your instrument is set to the correct altitude.
- You will also need a somewhat correct polar to get useful Alt a goal/Alt a BG values (And useful McReady speeds).
- The instrument glide functions cannot predict sink or lift on glide, only you can do that!
So there you have my setup, there are lots of information fields in the instrument so I am sure other pilots have different opinions on the optimal setup. Comments and questions are welcome!
(Not that I have been using the vario much lately – Here’s the weather outside as I write this)