The statement below is not mine, but I agree.
"This video is fresh (for the  public).  It was made just six weeks ago in the
Atlantic, just off Newport News (Hampton Roads), Virginia .
These  are the latest sea trials of the F-35B on the USS Wasp. They were
very  successful, with 74 VL's and STO's in a three week period. The media
and the  program critics had predicted that we would burn holes in the deck
and wash  sailors overboard. Neither of which happened. You will notice a
sailor  standing on the bow of the ship as the jet rotates. That was an
intentional  part of the sea trials.
Try viewing Full Screen - impressive.
No  catapult......    No hook ............      It's a new world out there.
It really is.
The shape and scope of  warfare - worldwide - just changed.    
http://www.youtube.com/watch?v=Ki86x1WKPmE&feature=colike Think - this new, monster killer  aircraft can land in a tennis court and
take off from it.
All the  "Special Ops" that always had to be executed from helicopters?  Look
at  this.  Warfare has just changed (again).   Thank God, that we, America ,
are the ones changing it  and keeping us safe"
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How would you like to be the test pilot flying this very expensive aircraft in deep water and lose it to an accident?
I think that raised hood device behind the cockpit is for air intake for the downward thrusting engines, not a speed brake.  
You can see the downward airflow over the water, after the jet leaves the boat.
I was in New Orleans on liberty when an English Harrier jump jet ship with the forward, up swooping, takeoff deck, aircraft carrier was also in port, before the Falklands War, about 1979 or so.  I got to tour their ship.  So the idea is not new, just the technology.