The role of Range Safety

The Range Safety Department is active at all times, whether before or during launches. Its basic mission remains the same, however: to ensure the safety of life, property and the environment.

The department defines the necessary conditions for safety and ensures that these are complied with. This involves developing and performing computer simulations of the effects of explosions, fires or deviation from rocket trajectories. The department carries out a wide range of studies, but over the years it has accumulated experience arising from all recorded incidents, and its methods have evolved accordingly.

To do its job, the department needs to be fully conversant with the type and probability of risks occurring in each phase. For this reason, the Range Safety team advances on two complementary fronts :

• during the pre-launch phase, with ground segment activities for preparing satellites, launchers and their corresponding facilities ;
• during and after launch, with the flight activities concerning the launch vehicle from lift-off until it has completed its mission.

Pre-launch phase

• During the satellite preparation and integration campaign.

The Range Safety team ensures that satellites are designed, built and operated in accordance with regulations, and similarly for the equipment used and the preparation procedures throughout the launch campaign. During all phases, the team is involved for dangerous operations, technical analyses and various other operations (such as fuelling, satellite transfer, etc.).

• Protecting the environment

The Range Safety Department is concerned with the protection not only of life and property, but of the environment as well. Going beyond just respecting the legal requirements, CNES undertook a procedure for ISO 14001 certification in environmental management. CNES thus does everything possible to minimise the impact of Space activities on the environment. With this in mind, several procedures have been set up for evaluating the impact of launches on air and water quality, the soil and the local flora and fauna.

• During launch vehicle preparation and integration

The Ground Safety team first ensures that operations on the launcher and the corresponding buildings are done in accordance with Range Safety regulations. It carries out various studies to identify the risks involved in various operations such as pyrotechnics, transferring elements of the launch vehicle, fuelling, pressurisation and so on.

The team then defines the danger zones as laid down in the regulations. It determines what resources will be necessary (firemen, preventive security and safety measures, weather forecasts) and reduces as far as possible the number of operatives needing to be exposed to risk.

• Developing safety regulations for launch vehicle flight

The Flight Safety team has to prescribe specific safety rules for the flight of the launch vehicle, analyse risks, ensure that the emergency arrangements are operational and take the decision to abort the flight if the launcher becomes dangerous.

Range Safety depends on two fundamental principles :

• The probability of causing death must be less than 1 in 10 million
• A double failure of any of the systems used by Range Safety must not be able to cause an accident with catastrophic consequences.

One of the missions of Flight Safety is to study launcher trajectories. They must present no danger for the population, even in the event of explosion. For each launch campaign, all possible failure scenarios are analysed (departure from planned trajectory, explosion etc.). The team also analyses meteorological information (wind direction and so forth) as well as the toxicity of satellite propellants that could fall back to Earth after an explosion.

During launch

During countdown, an operational Range Safety team ensures the safety of visitors on close observation sites. It oversees the evacuation of the public to a protected area in the event of any accident occurring to the launcher. Its members also inspect the danger zone by helicopter to make sure there is no-one in the area.

The mission of the Flight Safety team begins at T-6 hours. Then, at the moment of lift-off the teams watch out for any anomaly. If the launcher deviates from its flight corridor, measures must be taken immediately to protect inhabited areas by neutralising the launch vehicle. If the trajectory is normal, on the other hand, the team's mission ends as soon as the launcher no longer presents a danger to the population, property or the environment. The Flight Safety Officer then deactivates the launcher destruction system by sending the 'off' command.