Stop the chopper from escaping is a mission objective in Black Market Buy for Deus Ex: Mankind Divided.
Once the cutscene ends, head to the West. Jump from the ledge and perform an Icarus Strike as you descend. One of the assailants is found just below you and the Icarus strike disables them.
Jump out of the small area and start to the West. Take cover and head down the stairs. There are more assailants that you either want to run past these enemies or just take a few down and continue to the West then Northwest.
When you make it down to the level of the helicopter, you will want to rush over to it. Go to the front left portion of the helicopter.
Interact with the panel there will reveal the battery. Interact with the battery alone to disable the helicopter.
- Infiltrate the building
- Restore power to the keypad
- Seal off access to the Atrium
- Jam the signal boost (secondary)
- Stop the chopper from escaping
- Protect Singh (Secondary)