 Four of the reduced crew (including the captain), escaped the sinking ship but 15 did not, including Vernier.The "Kriegsmarine" conducted an investigation into the loss, at which it was revealed that either the captain or Vernier had ordered the submarine to submerge whilst travelling in reverse, thus unbalancing the boat and causing it to sink uncontrollably.A handful of men on the conning tower survived as the boat sank under them.