Both of the ALPS Space Frame platforms have now been raised into place on the west walkway.

To move each platform, ALPS installs four double reeved 1000Kg electric traction hoists, these are double reeved and generate a total of 8000Kg of lifting and lowering capacity.

ALPS install four independent secondary safety devises, these protect and back up the lifting systems.

The speed the ALPS platform is lowered at  ~4Metres/m so within 10 minutes of starting the lowering operation the platform is on the bridge deck.

Once on the bridge deck the pre-rigged ropes and safety devises are installed to the platforms hoists & safety devises and the platform raised into its new location on the west walkway.

The ALPS Space Frame platforms under the east and west walkways

The second Space Frame platform being lowered onto Tower Bridge

The Space Frame platform lowered to road level

The Space Frame platform being raised to the west walkway

The Space Frame platform in place under the west walkway