Romanian climate/territory is totaly different from the Israeli one - it's more unpredictable, especially in the mountains where the weather can change very fast. When the helicopter crashed there was a dense fog (one couldn't see more then 100-200m in front) and also was raining very hard and strong winds. The helicopter flew very low, close to the clifs so probably they saw the clifs to late and didn't have time to avoid the collision... For someone who never flew in these conditions is very hard and if Israel want's it's soldiers to be the best they need to fly in hardest environment.
Iranian parliamentary panel gives conditional nod to nuke deal (Reuters)
from the article: Why was an IDF helicopter training so far away from home?