The UAE military said in a statement Sunday the crash happened "during a routine flight over international waters."
The statement did not elaborate, nor did it offer any details on the type of helicopter involved, AP reported.
The UAE is part of a Saudi-led coalition now killing innocent Yemeni people.
The Saudi military has been engaged in military aggression against Yemen since late March. The strikes are allegedly aimed at undermining the Houthi movement and restoring power to fugitive former Yemeni President Abd Rabbuh Mansour Hadi.
About 9,100 people have lost their lives in the Saudi airstrikes, and a total of nearly 15,000 people have been injured since March 26.
It is also part of the US-led coalition purportedly fighting Daesh (also known as ISIL and ISIS) in Syria and Iraq.
In May, the UAE said another military air crash over water killed two on board during a training exercise.