Zsolt Ero

It's true but FAI calculates by the triangle sides, which in our case is determined by the center of the circle.

The FAI document is really quite low in details, but here is how I understand it: - You put 3 circles, such that they are 400 meter radius and they...

In the FAI rules, every time they calculate using the center of a cylinder (in declared records), you always have to subtract 2 * 400 meters for that cylinder. With...

Unfortunately here they don't provide any details: https://www.fai.org/records?f%5B0%5D=field_record_sport%3A2026&f%5B1%5D=field_record_category%3A125&f%5B2%5D=field_subclass%3A231&f%5B3%5D=field_type_of_record%3A330 I wrote them an email asking for clarifications.

I got an answer from FAI: > 5.2.5. Validation Using Start, Turn or Finish Cylinders > The record or badge distance shall be calculated as the minimum distance it is...

The writing "400 meters for each Start/Finish point." I believe is from the straight distance flights, where the points are different. In our case they are the same and it's...

I think for the mid-points we can do that, yes. For the start/endpoint I have no other idea but to make a one-off gradient descent-like algorithm. FAI replied that they...

I think I just figured it out. Basically igc-xc-score is doing everything perfect as it is now, with `closingDistanceFixed: 0.8`. The drawing in Section 7D about the triangle are wrong....

I think for the measurement it has to be Vincenty, that is the reference calculation for geographic distances. FAI currently uses SeeYou which from my experimenting produces the least precise...

Not strictly this ticket, but related: this flight gets calculated as 141 km in igc-xc-score (XContest profile) and 138 km in XContest. Do you know what could be the reason?...