AC313A, an improved civilian variant of the Z-8. Bullet points are as follows:
- Optimized engine layout, reducing engine installation loss (?) by more than 3%.
- New high-performance engine with improved lifespan and performance.
- Can operate 200% longer when carrying an external load of five tons, with great-than-40% high-altitude carrying capacity.
- Implemented HUMS (Health and Usage Monitoring System) and anti-icing system, improved safety, now capable of operating across all terrains and geographies.
- Better ease of maintenance, improved efficiency, reduced life-cycle cost.
The Z-8K is a dedicated PLAAF SAR variant based on the older Z-8A, whereas the Z-8F is or better to say was the project designation for the improved variant, which became later the AC313 or Z-18 and as such the Z-18F is the ASW variant of that type.