Testing the Halo - The science of saving lives
Novatech Measurements provide the precision sensors used to test the new addition to F1 safety regulations, which have already saved a number of lives.
What is the Halo?
The halo is a recently developed safety device fitted to an open cockpit racing car to provide much needed protection for the driver’s head, which is otherwise exposed above the main bodywork of the car. The halo consists of a thin front pillar supporting a curved bar above the drivers head, which is bolted to the car in three positions. The halo is made of grade 5 titanium for high strength without adding too much additional weight to the car. The version introduced in 2018 weighs around 9 kilograms.
Why was it introduced?
Racing in vehicles with open wheels and open cockpits has always been a dangerous profession. In the fifty years prior to the turn of the century, more than thirty drivers were fatally injured during competitive Formula 1 events. Improvements in the safety regulations over time resulted in there being only one death in Formula 1 in the twenty years that followed. However, there had still been a number of incidents and near misses in F1 and across a number of other divisions.
Efforts focusing on improved head protection started in earnest in 2009 when the son of former world champion John Surtees was killed by a loose wheel in a Formula 2 race. Just over a week later, Felipe Massa suffered life-threatening injuries when hit in the head by a loose spring during practice for the Hungarian Grand Prix.
Development and Testing
After several years of research and development, the FIA put a provision for the ‘Halo’ in the 2017 technical regulations and started conducting on-track tests in early 2016. The halo device was also extensively load tested at Cranfield Impact Centre, being one of just two FIA approved test centres in the world used for crash-testing Formula 1 cars.
The test regime was characterised in Article 17.2 of the 2018 Sporting Regulations to include; a load equivalent to 116kN vertically downward and 46kN longitudinally rearward at the peak of the Halo and a separate load case equivalent to 93kN laterally inward and 83kN longitudinally rearward along the side of the Halo. Matt Morris, Chief Engineering Officer at McLaren Racing, likened the test to the weight of a double decker bus being applied from an oblique angle.
For each test, peak loads had to be achieved in less than three minutes and be maintained for five seconds. After five seconds of application there had to be no failure of any part of the survival cell or of any attachment between the structure and the survival cell.
Engineers at Cranfield Impact centre adapted one of their rigs to perform the required tests using loadcells from Novatech Measurements. Our reputation for quality, precision and traceability has ensured that the FIA have used Novatech loadcells as the basis for their standard test equipment for more than twenty years.
Cranfield used one of our 200kN rated F202 loadcells in line with a small hydraulic jack that could be angled within the rig as necessary to meet the exact requirements of the test. The F202 consists of an axial strain cylinder in a sealed case, with raised load bearing faces at each end and a hole right through the middle. It is intended primarily for use in compression but can be used in a fail safe-tensile arrangement with the right fittings. The F202 is ideally suited to through centre safety testing of cables, rods and bolts as well as hydraulic press or jacking applications. It offers easy installation, usually between two flat faces, either unattached or with retaining spigots positioned in the centre hole. Using the same location method, accessories such as load spreader plates and load buttons can be used and these can be made to order.
A series of successful testing using F202 in the rig at Cranfield Impact Centre has lead to the mandatory implementation of the Halo on every vehicle in Formula 1, Formula 2, Formula 3, Formula 4 and Formula E since the start of the 2018 season.
Proven Safety Benefits
Initial simulations conducted by the FIA, based on over 40 real-world incidents, suggested that the Halo would improve driver survival rates by 17% in certain situations. This figure may not seem substantial at first but the Halo has already been credited with saving 5 lives in as many years since its introduction. In the 2018 Belgian Grand Prix, Charles Leclerc's halo was struck by Fernando Alonso's airborne McLaren, with both of their halo devices showing visible damage from the impact. Leclerc later credited the halo for saving his life.
In another high-profile incident, the halo protected Romain Grosjean at the 2020 Bahrain Grand Prix where, after hitting Daniil Kvyat's car, he crashed into the barriers head-on. The front strut of the halo successfully managed to deflect the upper section of the barrier over Grosjean's head as the nose of the car speared through the barrier, unexpectedly splitting it in two. The car broke apart and was immediately engulfed in flames but the survival cell remained intact along with the Halo, allowing Grosjean to climb out largely unassisted. He emerged from the flames with no worse than burns on his hands and ankles, later saying to an interviewer that he "wasn't for the halo some years ago” but now thinks “it is the greatest thing that we've brought to Formula 1” and without it he “wouldn't be able to speak to you today."
The following year, at the 2021 Italian Grand Prix, Max Verstappen and Lewis Hamilton collided, sending the Red Bull into the air. Verstappen's wheel landed squarely on the halo of the Mercedes, forcing Hamilton’s head forward into the front of the cockpit. Crucially, the halo prevented the entire weight of the Red Bull from bearing down on him, with Hamilton later saying it "saved my neck".
The Halo devices are now subject to a yearly test to ensure that they remain fit for purpose and continue to protect the lives of the drivers. The inclusion of Novatech loadcells in this application guarantees that the tests are performed in line with exacting standards and to a high degree of precision as befits any safety critical process.