As you asking for the procedure of the service selection board of interview of the AFCAT examination for joining the Indian air force let me tell you that the interview is goes for the Five days the procedure of the interview conducted by the SSB are given below :

First day tests
During the first day of SSB interview only psychological tests are conducted. Following tests are conducted during the first day of five day SSB interview.
Intelligence Test
Picture Perception and Description Test (PPDT)
Filling up of Personal Information Questionnaire (PIQ) forms

Second day tests
Following tests are conducted during the second day of SSB interviews.
Word Association Test (WAT)
Thematic Apperception Test (TAT)
Situation Reaction Test (SRT)
Self Description Test

Third day tests of SSB interview
Following tests are conducted on the third day.
Group Discussion test
Military Planning Exercise (MPE)
Lecturettes
Progressive Group Task (PGT)
Intergroup Obstacle race or Snake race
Half Group Task
Command Task
Personal interview for some of the candidates by president

Fourth day tests
Following tests are conducted during the fourth day of SSB interviews.
Final Group Task (FGT)
Individual Obstacles
nterview for remaining candidates

Fifth day tests
On fifth day, only final board conference is conducted and the results are announced by SSB board officials. Thus the following events and tests will be there on fifth day of SSB interview.

Conference
Announcement of recommended candidates