A turbo-charger which is designed to maintain sea level pressure at altitude is termed:

A turbo-charger designed to maintain sea level pressure at altitude is known as an altitude-boosted turbo-charger. This type of turbo-charger is specifically engineered to compensate for the decrease in atmospheric pressure that occurs as an aircraft climbs to higher altitudes.

As the altitude increases, the air density drops, which means that the engine would naturally receive less air for combustion, potentially leading to a loss of power. An altitude-boosted turbo-charger addresses this challenge by ensuring that the engine continues to receive sufficient air pressure, simulating the pressure found at sea level. This capability allows for better performance and efficiency at high altitudes, helping the aircraft to maintain its power output.

In contrast, other options such as turbo-superchargers or ground boosted turbo-chargers do not specifically denote the function of maintaining sea level pressure at altitude. A turbo-supercharger usually refers to a system that combines turbocharging and supercharging but is not specifically tailored for altitude conditions. Internal superchargers are generally a different type of system altogether focusing on different aspects of engine performance. Ground boosted turbo-chargers typically refer to systems that enhance performance on the ground rather than at altitude. Thus, the specific design intent and functionality of an altitude-boosted