Final answer:
The 10th-stage and 14th-stage engine bleed-air shutoff valves (SOVs) are spring-loaded to ensure closure during engine operation, preventing uncontrolled bleed air flow and potential damage to the engine.
Step-by-step explanation:
The 10th-stage and 14th-stage engine bleed-air shutoff valves (SOVs) are spring-loaded to ensure their closure during engine operation. These valves are used in aircraft engines to control the flow of bleed air, which is taken from the compressor section of the engine and used for various purposes such as air conditioning, anti-icing, and pressurization. The spring-loaded mechanism ensures that the valves close automatically if there is a loss of hydraulic or electrical power, preventing uncontrolled bleed air flow and potential damage to the engine.