Landing Craft (Barge) DOORS/RAMPS

[Specmar.Aus]

Hello All at Boat Design.Net

Landing Craft Articulated Bow door / Ramps.

I have been searching the Net for design details on how these doors work, (mechanically)
Most fold back over the raised section horizontally when underway.
This allows a far better field of vision forward than just simply extending the ramp section.
We would prefer to use Aluminium for all the components on a 42 foot Landing Craft,
The max weight over the ramp / door would be less than 10,000 Lbs.

Can anyone assist with some links or photos ECT?

Cheers Specmar.Aus