Landing leg deployment.

Notes

1. Deployment starts when the upper doors slide inside the hull to let the landing legs descend.
2. The legs descend until they are flush with the hull. There are lower doors, attached to grooves on the underside of the legs. The doors descend with the legs.
3. The grooves on the undersides of the legs are now aligned to the grooves on the outer hull so the doors can now rotate out of the way.
4. The legs descend and rotate into their deployed positions.
5. The cargo bay door descends then rotates out of the way.

The picture below shows the slots in the hull that the upper doors slide into.

You can also see slots in the lower doors that the upper doors slide into. Upper and lower doors overlap. The upper doors must slide away before the lower doors can descend.