Flight safety when parachuting is lacking and needs to be sharpened considerably - this is the opinion of several relatives of those who fell victim to the plane crash in Umeå last year.

- If I had known what I know today, I would have said no when Carl would start jumping.

It feels too dangerous, says Rolf Edling.

They believe that the accident in Umeå could have been avoided if only lessons had been learned from a similar plane crash in Finland's Jämijärvi, 2014. Eight jumpers died after the plane's wing gave way in the air.

After the accident, the investigation proposed, among other things, a targeted training for pilots and clearer guidelines for how to load and move in a parachute plane.

"If the recommendations made by Finland's Havkom had been adopted as regulations and applied in Sweden - then the accident in Umeå would probably never have occurred," they write in an open letter sent to several media.

- We have followed the rules and restrictions that existed at the time.

Of course, it is important to analyze this in the continued work, says Navid Haghjo, chairman of Umeå Parachute Club.

"Safety margins were very small"

Now they are appealing to the European Aviation Safety Agency EASA, Swedish parachute clubs and pilot associations to review and increase safety in parachuting.

Read the entire open letter from the relatives below and also answers to the criticism from Umeå parachute club chairman.

Hear more in the clip.