The largest and most visible sky sign in Sydney has been attached to the side of Sydney Tower.

The new Westfield signage reflects the retailer’s recent move into the building.

Claude Neon, which made and installed the two new signs to the east and west elevations of the tower, said street closures in the CBD, evacuations and a helicopter installation were required to complete the task.

A helicopter was equipped with a 65 metre lifting rope to ensure it hovered clear of the Tower and its spire. Assisted by abseilers, each new section was secured in place.

All up, the installation took just over one hour of airtime for the twin engine helicopter — another safety aspect of the operation, ensuring that if one engine failed, the helicopter could fly the load and land safely.

Sign Statistics

The W measures more than 6.36 metres in height and the length of each elevation is 22 metres - making this the biggest sky sign in all of Sydney.

In all, more than 3,000 red LEDs — 3,041 to be exact — light up the sign, which was manufactured in aluminium to keep its weight down to 2.5 tons. The letter faces are manufactured in polycarbonate and are secured to the aluminium frame. The signs were designed to withstand winds of up to 280km.