8411.21 - Of a power not exceeding 1,100 kW:

This HTS category, 8411.21, encompasses turbopropellers designed for a specific power output. Turbopropellers, by definition, are a type of gas turbine engine where a significant portion of the exhaust gas is used to drive a propeller. This classification is specifically for those engines where the rated power output does not exceed 1,100 kilowatts (kW). The key distinguishing factor is this power limitation, which separates them from more powerful turbopropeller units.

In contrast to its sibling category, 8411.22, which covers turbopropellers of a power exceeding 1,100 kW, this heading strictly limits its scope to engines below that threshold. This distinction is critical for accurate tariff application, as different power ratings can influence duty rates or regulatory requirements. The function of these engines is typically for aircraft propulsion, where their efficiency and power delivery characteristics make them suitable for a range of aircraft types.

Within this classification, further subdivisions exist to refine the classification based on the specific application. The subcategories of 8411.21.40.00 and 8411.21.80.00 differentiate between aircraft turbines and other turbopropellers, respectively. This allows for more granular reporting and analysis of imported or exported goods, catering to the specific needs of the aviation industry and other potential applications for lower-powered turbopropeller systems.