Some of the Exo pilots are sympathetic to our cause. If you happen to see one once their Exo is destroyed, pick her up, and bring her back here. She might have intel on their movements, plans - anything useful. Get her back here safely.
Exos can be forced to spawn with the quests Red Baron's Legacy and Rust In Peace on Elephant Mausoleum and Underground Cemetery, respectively. Exos have a random chance to spawn at set locations on all maps except Scrapyard Nexus and Underground Cemetery.
Any extract
Bunkers
Big bowl in the west
Loading scripts
Motor pool. Often falls into the trench
Hangar. If Red Baron's Legacy is active, the Baron will spawn along with the regular Exo
Find an Exo and wait for it to be destroyed. You can also destroy it yourself using a grenade launcher or another high damage weapon, but doing so will attract Hunter Killers and drastically lower your faction rating with Europa.
Pilots are guaranteed to spawn as long as the quest is active. Pilots are a large item, requiring an appropriate slot in your rig. They may be concealed by the flames from the vehicle.
If you ping it, they will show up as <Item>. Repeatedly pinging the fire near the destroyed Exo can help if you are unsure whether the pilot dropped or not.
Using a Tactical Camera is highly recommended, as you can spot the Pilot more easy under the Flames and debris
Pick up the pilot and extract with her to complete the quest.
The pilot will become available as a unique recruit.
Trivia
This quest is depicted in Burst Transmission 1.0 - Europa EXO Lifecycle.
With 10k XP per turn-in, the pilot currently shares the first place for highest XP with the Corpse Tank Control Panel.
Example of a Europan Exo
Exo pilot on the ground
More than one pilot can be found and picked up during a run