The Penumbra Marine Logistics (PML) Air Cradles started as a fun idea in the Ft. Lauderdale PML facility back in 2006. Today there are now dozens of “Hover Cradles” on yachts all over the world with everything from Wave Runners, Tenders, Exercise equipment, to Personal Submarines weighing close to 10 tons. The largest cradle we built to date is rated for over 20 tons although capacity is almost unlimited.
Cradles are custom made per application or special requirements from the yacht owners, captains, or shipyards.
The Hover Cradles operate on only 3-4 bar (~45-60 psi) and hover only a few millimeters off the deck or a smooth surface.
- Powder Coated 304 Stainless Steel
- Polished 316 Stainless Steel
- Powder Coated Steel
Cradle construction varies, as does the construction time and cost. The Powder coated 304 Stainless Steel is the most popular, followed by the highly polished 316 Stainless Steel. Additional weeks of polishing is required for the stainless. This and the materials drive the cost up considerably. We have been asked to build units in mild steel and powder coat but do not recommend.
Penumbra recently built and delivered this 42,500 lb (19,300 kg) capacity Air Cradle to hover this 10 ton submarine around the deck on a cushion of air.
Yes that is a Seaplane on the deck behind the sub!
Cradle being operated at Triton Submarines. Operating pressure is 4-5 bars.
Other Cradles designs for Feadship, Oceanco, Nobiskrug, and more.
Video made by the original owner of Harbor Island.