The four crew on the Navy helicopter escaped without serious injury and were winched to safety by an RAF search and rescue helicopter.
![[ image: width=150]](/olmedia/165000/images/_165024_Norfolk_map.jpg)
The Sea King, from HMS Culdrose in Cornwall, plunged into The Wash about 15 miles off the Norfolk coast, the same area where an RAF Jaguar crashed on Thursday.
The Jaguar pilot, based at RAF Coltishall, in Norfolk, ejected safely and was picked up unhurt.
The fighter bomber had been taking part in a routine training flight with other Jaguars when it plunged into the sea.
The MoD would not say whether the Sea King was taking part in a mission connected with Thursday's accident.
A spokesman said: "It's too early to speculate on what the helicopter was doing."
He added that a board of inquiry was being convened to investigate the incident.
The Sea King, which is fitted with flotation equipment, was to be salvaged from the surface by a recovery vessel.
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