How a three-axis machine revolutionised aircraft construction

20 October 2025

While the recent EMO 2025 exhibition celebrated its 50th anniversary, Starrag looks back on an engineering anniversary of its own: 25 years of Sprint Z3. The inconspicuous machining head of the ECOSPEED series was officially presented for the first time in the year 2000. What began as a solution for a military aircraft became a key module in modern aircraft production.

The Sprint Z3 parallel kinematic machining head has proven to be a real drawcard and, despite its compact design, is always a talking point.

Parallel kinematics in series production worldwide

Even after 25 years, the technology behind it still amazes. The drive head contains a highly dynamic, 3-axis kinematic system, which, unlike conventional fork heads, swivels via articulated kinematics and thus enables rapid, precise tool movements. The mechanics are based on three Z-modules that ensure linear movements – free of contact rings and rotary couplings, which increases rigidity, reduces wear and ensures consistently high precision.

First military, then civilian

The Sprint Z3 was introduced as the central element of the new ECOSPEED series – a high-performance machine series for the fast cutting of large aluminium components. Originally developed for military structural parts, the parallel kinematics concept quickly became established in civil aviation as well. Today, this 3-axis machine is the global standard for machining complex aircraft structures.

Digital alliance with IPS

Now, the Sprint Z3 shows its particular strength when networked with the Integrated Production System (IPS) – Starrag's modular digitisation concept. It combines ECOSPEED systems into highly automated, flexible production systems with a high level of transparency, process reliability and availability.

The Sprint Z3 also benefits from sensors on the spindle, drives and axes that continuously supply data that is analysed by IPS modules. This supports condition monitoring, process optimisation or preventive maintenance. The motion control system of the 3-axis milling head remains in the CNC, but the IPS provides the decision-making basis for stable and productive machining – a digital interplay of precision and intelligence.

Fast machining of A350 wing ribs

The example of Korea Aerospace Industries (KAI) shows just how efficient this connection is. The company operates one of the world's largest interlinked ECOSPEED lines – with nine machines, four set-up stations, two transfer carts and around 90 pallets. The machining times for the wing ribs of the Airbus A350 have been reduced to around a fifth of those for earlier conventional aircraft. The availability of the line is around 97% – proof of the high efficiency and reliability of the system.