Which type of hydraulic fluid is known for its fire-resistant properties and is commonly used in commercial aircraft?

The type of hydraulic fluid recognized for its fire-resistant properties and widely utilized in commercial aircraft is Skydrol. This particular fluid is a phosphate ester-based hydraulic fluid, which is specifically formulated to not ignite easily in high-temperature environments, making it ideal for aviation applications where fire safety is a paramount concern.

Skydrol is engineered to handle the demands of aircraft hydraulic systems, including resistance to thermal breakdown and environmental conditions encountered in flight. Its use in commercial aircraft is prevalent due to these properties that enhance operational safety and reliability.

In contrast, the other hydraulic fluids listed may not possess the same degree of fire resistance or suitability for aviation. For instance, MIL-H-83282 is a military specification hydraulic fluid, and while it is high-performing, it does not offer the same level of fire resistance as Skydrol. Mineral oil is generally not used in aviation hydraulics due to its flammability and lower performance at extreme temperatures. Aeroshell Fluid is primarily used for different applications, not specifically in the primary hydraulic systems of commercial aircraft where fire resistance is crucial.