Unstable at pull time , He is a very experienced base jumper and was a leader in the valley for keeping good relations between the base jumpers , media and locals also is part of the Swiss Base Association (SBA), Numerous jumpers have said that he is the most meticulous and safety conscious Jumper they have ever come across and is a huge shock to the jumping commmunity in switerland..

update from Mäthu / SBA

So, here is what happened:

Markus jumped the Via Ferrata alone in late afternoon and in calm conditions, no turbulence. He was flying his Apache that he had been using for quite a while already. He felt comfortable in the suit - that's what he told me on several occasions during the weeks/months before the accident.

A credible eye witness saw Markus flying left after the exit along the wall towards Lauterbrunnen. He was flying stable and with a very impressive glide. At about two thirds of the way to the waterfall and still very high up he initiated a right turn to separate from the wall. After about 70-80 degrees and while still turning he suddenly went steep, respectively nosedived, which resulted in an abrupt "frontflip". The exact kind of flip/rotation and in which position he came out of it cannot be said with enough certainty. After this flip he could have recovered easily as he was still very high. Instead he was tumbling towards the ground as if he was unconscious: no trying to recover, no struggling, no flat-spinn, nothing, just falling like a stone with flapping fabric on it. This tumbling part of the flight was also seen be another witness. Moreover, the coroner mentioned that the body was "unusually relaxed" and not stiff like other bodies of basejumpers that he had treated, supporting the presumption that Markus was unconscious. Markus impacted the field west of the bridge near the waterfall with nothing out and died instantly. We inspected his gear and it is obvious that the pilot chute was still in the BOC when he impacted. Everything on the gear looked okay, including the wingsuit.

What caused the abrupt nosedive resulting in a flip we will never know exactly. Our assumptions are:

1) Markus suffered a sudden health problem, be it a heart attack, a stroke or just a momentary black out.

2) The wingsuit stalled during the turn, went into an aggressive nosedive and with a resulting negative AoA flipped Markus abruptly, rendering him unconscious. This theory could be backed by the fact that Markus' flightpath was considered "very high", meaning he must have been close to stall speed on the polar curve, invariably leading to the danger of a dynamic stall while turning. Additionally, by design a large wingsuit such as the Apache is more prone to radical stall behaviour.

That is all we could find out.