Complex sentence: Notably, the ALF 502 had a very low level of operational noise, much lower than most other competing aircraft, this was achieved partly by the engine's high bypass ratio along with additional sound dampening layers built into the engine.
Split into simpler sentences: Notably, the ALF 502 had a very low level of operational noise, much lower than most other competing aircraft. This was achieved partly by the engine's high bypass ratio along with additional sound dampening layers built into the engine.