US Navy test article from Cargotec demonstrates vehicle transfer at sea

A test article ship-to-ship vehicle transfer system from Cargotec is on its way to the US Navy; the test article uses MacGregor-based technology and can transfer US Marine Corps vehicles and personnel from a large medium-speed RO/RO to a mobile landing platform in sea state 3

As part of a development project Cargotec is delivering a test article ship-to-ship vehicle transfer system to the US Navy using MacGregor-based technology. The test article vehicle transfer system (TAVTS) has been built as part of the US Navy’s ‘Sea Base’ plan to support Army and Marine Corps land forces.

The two primary components of the transfer system are a self-deploying ramp that will be mounted to the float-on/float-off ship, Mighty Servant 3, and a self-deploying sideport platform system fitted to the large medium-speed roll-on/roll-off (RO/RO) (LMSR) ship, USNS Soderman.

Installation of the ramp system on Mighty Servant 3 will simulate the basic configuration envisioned for the future mobile landing platform (MLP). The surrogate MLP will be fitted with a dynamic positioning (DP) system that will allow it to hold a specified position and orientation alongside the LMSR while underway, within a defined tolerance.

The TAVTS will be used by the US Navy to demonstrate vehicle transfer between the surrogate MLP and the LMSR. The ramp is power-operated for deployment and retrieval and is controllable by one person. In case of failure, the system is able to safely continue to support vertical and horizontal design loads and allow emergency ship separation with a vehicle – up to a weight of 72,575kg (160,000 lb) – anywhere along the length of the ramp.

Prior to its recent delivery, Cargotec finalised rigorous harbour test procedures on the system, which will now undergo full-scale testing by the US Navy’s PEO Ships/PMS 385.

The test objectives are to demonstrate:
â€¢ the MLP’s ability to maintain station alongside the LMSR in sea state 3
â€¢ the test article ramp’s ability to deploy to and operate with its new LMSR sideport platform in sea state 3
â€¢ the transfer of US Marine Corps vehicles and personnel via test article ramp from the LMSR to the MLP and back again in sea state 3.

All test procedures are performed using the ‘crawl, walk, run’ method, which is a graduated approach. Testing will start with alongside/at anchor demonstrations moving to open water/low sea state conditions and finishing with open water/increasing sea states. Operations specialists have conducted site surveys in the Gulf of Mexico to investigate suitable test locations.

TAVTS-ramp at “safe distance mode”