I am Jinhyung SONG, a member of CIVL pilot and one of the directors of Korea Hang and Paragliding Association.
In Asian Championship the UTM-xy is used as the GPS coordinate format. The only reason is very practical, of course important also. To prevent input mistakes.
But several years passed, the environment has been changed. And there are many reasons to use WGS84 Degree-Minute-Second format.
I think that considerations and discussions are needed about adopting WGS84 ddd`mm'ss" as the GPS coordiante format.
● Following, the reasons that ddd`mm'ss" format is better.
1. Originally XC belongs to air flight.
This is general reason. In navigation and air flgiht, ddd`mm'ss" format is used. Because they move around on the earth sphere. We are also air pilots. ddd`mm'ss" format is familiar and intuitive.
2. Readablility.
ddd`mm'ss" format is better than UTM-xy when reading, memorizing, inputing and informing to others, because it is seperated by degree, minute, second. On the other hand, UTM-xy is continuous six or seven numbers
For example 36'43"52 N 128'10"28 E and X=426301 Y=4065368.
3. Compatiblity to others.
Of course air force and airport use ddd`mm'ss". In South Korea, almost official organizations use ddd`mm'ss" except the army, they use UTM-xy exclusively.
Especialy, emergency rescue sevice 119 (correspondent to 911 in United States) uses ddd`mm'ss". When calling 119 in accident, UTM-xy may cause a problum.
In Apple iPhone, built-in compass application shows the position by ddd`mm'ss" format. And almost Android applications uses also ddd`mm'ss".
In our environment, the ddd`mm'ss" format is accepted as standard.
● The reason to use UTM-xy format has decreased and can be overcome.
In ddd`mm'ss" fomat, the input mistakes occur only when following conditions. The error distance is sevral hundred meters.
1. The map datum is not WGS-84 (For example, Tokyo, Hong Kong, Austria etc). Flying GPS instruments like Flytech, Brauniger have only WGS-84 in ddd`mm'ss". So problum cannot occur when using these. Garmin may cause problum.
2. The waypoints are inputed manually. (Of course, when inputed by PC uploading there is no problum, regardless of setting)
So the condition is that some GPS (like Garmin) AND setting is not WGS-84 AND inputed waypoints manually. This is rare case.
Sevral years passed, GPS instuments for XC competitons are more used, outdoor GPS like Garmin is reduced. And also now manual waypoints input is not often.
When waypoints are inputed manually at breifing place, there is simple method to prevent mistakes. The director writes coordinate of that place on the task board and let the pilots compare it to their own instruments.
It is pilot's duty to input waypoints correctly. No more consideration is needed.
● Conclusion
The reason to adopting ddd`mm'ss" is increasing, including safery reason when calling emergency rescue serive, but the reason to use UTM-xy is decreasing. I want deep considerations, please. Thank you.