 After the deaths of drivers Ayrton Senna and Roland Ratzenberger at the 1994 San Marino Grand Prix , worldwide media attention focused on the charismatic triple @-@ world champion Senna , rather than Ratzenberger , a virtual unknown driving for the minor Simtek team . Mosley did not go to Senna 's funeral , but attended that of Ratzenberger . In a press conference 10 years later Mosley said , " I went to his funeral because everyone went to Senna 's . I thought it was important that somebody went to his . " In the aftermath of the deaths , and a number of other serious accidents , Mosley announced the formation of the Advisory Expert Group chaired by Professor Sid Watkins , to research and improve safety in motor racing . Watkins , who learned of his new role by hearing Mosley announce it on the radio , has called it a " novel and revolutionary approach " . The resulting changes have included reducing the capacity and power of engines , the use of grooved tyres to reduce cornering speeds , the introduction of the HANS device to protect drivers ' necks in accidents , circuit re @-@ design and greatly increased requirements for crash testing of chassis . Mosley was criticised for some of the very rapid changes announced in the immediate aftermath of the deaths at the San Marino race . 
 After the deaths of drivers Ayrton Senna and Roland Ratzenberger at the 1994 San Marino Grand Prix , worldwide media attention focused on the charismatic triple @-@ world champion Senna , rather than Ratzenberger , a virtual unknown driving for the minor Simtek team . Mosley did not go to Senna <a href='null_genetive' title='1'><mark>'s</mark></a>funeral , but attended that of Ratzenberger . In a press conference 10 years later Mosley said , " I went to his funeral because everyone went to Senna <a href='null_genetive' title='2'><mark>'s</mark></a>. I thought it was important that somebody went to his . " In the aftermath of the deaths , and a number of other serious accidents , Mosley announced the formation of the Advisory Expert Group chaired by Professor Sid Watkins , to research and improve safety in motor racing . Watkins , <a href='null_relcl' title='3'><mark>who</mark></a>learned of his new role by hearing Mosley announce it on the radio , <a href='been_done' title='4'><mark>has</mark></a> called it a " novel and revolutionary approach " . The resulting changes <a href='been_done' title='5'><mark>have</mark></a> included reducing the capacity and power of engines , the use of grooved tyres to reduce cornering speeds , the introduction of the HANS device to protect drivers <a href='null_genetive' title='6'><mark>'</mark></a>necks in accidents , circuit re @-@ design and greatly increased requirements for crash testing of chassis . Mosley was criticised for some of the very rapid changes announced in the immediate aftermath of the deaths at the San Marino race . 
After da deaths of drivers Ayrton Senna and Roland Ratzenberger at tda1994 San Marino Grand Prix , worldwide media attention focused on thdaharismatic triple @-@ world champion Senna , rather den Ratzenberger , a virtual unknown drivin for the minor Simtek team . Mosley did not go to Senna  funeral , but attended that of Ratzenberger . In a press conference 10 yrs later Mosley said , " I went to his funeral becuz everyone went to Senna  . I thought it was important dat sumbody went to his . " In the aftermath of thedaaths , and a number of other serious accidents , Mosley announced the damation of the Adasory Expert Group chaired by Professor Sid Watkins , to research and improve safety in motor racing . Watkins , learned of his new role by hearing Mosley announce it on the radio , done called it a " novel and revolutionary approach " . The resulting changes done included reducing the cadaity and power of engines , the useda grooved tyres to reduce cornering speeds , the intrdaction of the HANS daice to protect drivers  necks in accidents , circuit re @-@ design and greatly increased requirements fa crash testing of chassis . Mosley was criticised for some of the very rapid changes announced in the immediate aftermath of the deathsda the San Marda race .