South Korea’s leading low-cost carrier, heavy with debt and its stock already near record lows, is now facing intense public and government scrutiny.

South Korea has vowed thorough investigations to find what caused a plane crash that killed 179 people, saying Monday that it will also inspect all Boeing 737-800 aircraft operated by the country’s airlines.

Investigators assessing the survivability of a plane crash focus on five factors: integrity of the aircraft, effectiveness of safety restraints, G-forces experienced by passengers and crew, the environment inside the aircraft and postcrash factors such as fire or smoke.