The French Navy has initiated the modernization program for the inertial navigation systems of the Mistral-class multirole helicopter carriers (PHA).
Thales, CNN MCO, an Equans France company, and CS GROUP, a subsidiary of Sopra Steria, were put in charge of the relevant program.
#### A New Inertial Navigation System
At the heart of the program is the development and integration on board the three Mistral class PHAs of a highly resilient new inertial navigation system, designed for electronic warfare environments.
Following the successful conclusion of the development and trial phase, a system has been installed on board the Mistral PHA.
Awarded to CNN MCO in 2022 for a period of eight years, the contract covers all onboard systems of the three PHA ships of the French Navy, Mistral, Tonnerre, and Dixmude and also includes the in-service support of the command and supply ship Somme.
The aim of the program is to guarantee the availability at sea and the full operational capability of these platforms in an increasingly challenging strategic context.
#### Thales’s TopAxyz System
Thales will provide the TopAxyz inertial navigation system which relies exclusively on internally controlled data, without any dependency on external sources.
Using onboard sensors like accelerometers and gyroscopes, TopAxyz measures the ship’s movements to constantly calculate its position, speed, and route, without the need for external signals like GPS.
#### The Role of CS Group and the Integration by CNN MCO
Thales’ inertial navigation units will be integrated into the CS Group’s global navigation system.
Since the navigation system constitutes the backbone of a warship, ensuring positioning accuracy and maneuvering safety, this technological partnership guarantees precision, resilience, and continuity of service in the most challenging maritime environments.
The integration of these new systems, implemented by CNN MCO, meets strict safety requirements and leverages existing infrastructures.
To date, the retrofit studies have required almost 1,500 hours of engineering work by CNN MCO’s internal design office, in collaboration with Thales and the CS Group.
#### The Program Timeline
The Mistral will be the first PHA to benefit from the new system, followed by the Dixmude and Tonnerre.
Once the Thales inertial units have been integrated into the navigation modules by the CS Group, the systems will be installed by CNN MCO on the three ships, with a gradual increase by 2027.
CNN MCO is responsible for the integration, supervision of tests, and maintenance of the equipment, working directly with the Fleet Support Service (SSF) teams.
The consortium’s goal is to optimize the installation windows during the technical maintenance period of the three PHAs to guarantee the best operational availability of the systems at sea.
Source: Thales
Photo credit: @French Navy
