Atlantis, majority owner of the MeyGen project, said Lockheed will manufacture the steel turbine housing and assemble parts including the gearbox and generator.
The companies, which have worked together for several years, said they were looking to use local firms where possible on the turbine build. The 18-metre rotor diameter turbine will be one of the largest capacity single rotor turbines ever built.
The turbine will be one of four devices in the first phase of the MeyGen project and is scheduled to arrive in Scotland for installation in 2016.
Atlantis eventually plans to have up to 269 turbines on the seabed in the Pentland Firth between Caithness and Orkney.
Last year the company secured more than £50m in funding for the first phase of the MeyGen project, including backing from the Scottish Government, Highlands and Islands Enterprise, the UK government and the Crown Estate.
Tim Cornelius, chief executive of Atlantis, said the Lockheed Martin contract was a further development in the work of the two companies at what he described as the “forefront of tidal power generation”.
“Lockheed Martin has been a strong partner and supporter of Atlantis for a number of years and we look forward to continuing to work alongside this global technology giant as we continue to deliver turbine systems for installation on the MeyGen project.”
Atlantis also said that contractors had yesterday started horizontal directional drilling operations at the MeyGen construction site in Caithness to create the bores for the cables which will link the onshore site at Ness of Quoys with the four subsea turbines.
Each of the four bores will be around 550 metres long, and is designed to contain a 4.4kV cable through which tidally generated energy can be exported from the turbines to the onshore grid connection.
The drilling is expected to take four months and will be carried out by Manchester-based O’Connor Utilities. Construction works have been underway at the onshore site since January.
MeyGen was one of the first tidal projects in the world to secure the necessary planning consent, lease agreement, grid connection and power purchase agreement in order to begin onshore and offshore construction.
Construction of the first phase of the project is expected to take place throughout 2015 and 2016, with first power being delivered to the grid for sale in 2016.