Final answer:
Oxygen masks on aircraft can be deployed through a pressure switch, manual release by the crew, or an electrical signal, to ensure passenger safety during emergencies such as loss of cabin pressure.
Step-by-step explanation:
The question 'What are the three ways the oxygen masks are dropped?' is related to aircraft safety systems, specifically the deployment mechanisms for oxygen masks in the event of cabin depressurization. Oxygen masks can be deployed in one of three ways, each utilizing a different triggering mechanism:
- Pressure switch: Most commonly, an automatic pressure switch detects when the cabin pressure falls below a certain threshold and triggers the release.
- Manual release: Crew members have the ability to manually release oxygen masks.
- Electrical signal: An electrical signal from the cockpit or another system can initiate the mask deployment.
These mechanisms are designed to ensure that passengers have access to oxygen in case of an emergency, such as loss of cabin pressure at high altitudes.