Satellite Central Cylinder Structures

Satellite Central Cylinder Structures from RUAG Space are used on a large number of satellites and are created with over 30 years of experience from Carbon fiber production.

The Central Cylinder of a satellite could be compared to the spinal cord of a human being: It provides the mechanical support of all equipment, decks, panels, electronics, and propulsion tanks. Created with over 30 years of experience from Carbon fiber production, RUAG Central Cylinders are used on a large number of satellites.

With the optimized ultra-light RUAG Satellite Central Cylinder Structure, a 60 kg Cylinder can carry satellite equipment with a mass up to 4 metric tons and still handle the accelerations and loads of a space launch.

The central cylinders can be made to accommodate the common space busses, up to 5 m in height and with the standard 937 (37 inch), 1194 (47 inch) or 1666 (66 inch) launcher interface.




  • Low structural mass
  • High local loads
  • 100% dimensional accuracy
  • Ultra-light carbon-fiber sandwich structure
  • Unique insert technology
  • 100% structural inspection



Customer Values

  • Advanced materials and processes
  • Special assembly jigs and tools
  • Airborne ultrasonic testing
  • High product precision and accuracy
  • Shortened satellite integration time
  • 100% mission success

More information about 3D Printing.

Sandwich Design

The RUAG ultra-light Satellite structure is a sandwich composite structure with a mass and stiffness optimized design. It typically has a large number of different load zones with varying thickness and density all adapted to customer needs.

The Sandwich outer layers consist of CFRP (Carbon Fiber Reinforced Plastic) and aluminum honeycomb sheets make out the inner layer. For optimization purposes the carbon fiber skin thickness can vary between 0.3 and 10 mm.

The core of the sandwich is laid-up using a range of different density honeycomb sheets, all with the purpose to minimize mass.

Reliability and Quality

For the initial launch and subsequent years in space the reliability and quality of the structure is crucial. The quality inspection is thorough and a vital part of the manufacturing process. Due to very thin skins in parts of the product, a special ultrasonic scanner is used to test the integrity of the structure before mounting inserts.


On a product with more than 600 inserts, to accommodate tanks, decks, corners and tubes, the accuracy of these holes is vital to meet the overall product quality requirements and schedule. Here is where you start to build your satellite and want reliability,quality and precision.

In order to achieve the needed accuracy, special tools are created to exactly match the chosen insert interfaces. These tools are then used in the manufacturing, resulting in a product that needs no further trimming once it leaves the assembly rig.

Main Characteristics of RUAG Central Cylinder




Value 1)




Up to 5m

Launcher Interface

Interface ring


937, 1194, 1666 






Sandwich structure


Sandwich structure made of CFRP and Aluminum honeycomb




Titanium or aluminum

Satellite key data

Overall satellite mass



Structural integrity test



Complete Ultrasonic scan and X-Ray

Picture: Satellite Central Cylinder Structures