These paratroopers are specialized in reconnaissance.

The mercenaries spied a military aircraft conducting aerial reconnaissance over the area.

A reconnaissance satellite is a military satellite capable of monitoring many activities on earth, eavesdropping on lines, registering the operating frequency of the radar systems...

The aircraft was conducting aerial reconnaissance.

You have been up to the scene of the crime, I understand," said the Colonel. "Yes; the Inspector and I have made quite a little reconnaissance together."

We were here on a reconnaissance mission.