i guess its not just the indian mig21, or bisons pak migs/f-7 also are in dire need of replacement. But then the question is both paf and iaf fly other planes like jaguars and mirages in greater numbers, and they have lower crash rate why?
Not sure but i have some theories, request any senior member to validate them
1) These aircrafts are old and less advance hence are given lower importance in maintanance, storage of planes which is resulting in failiurs
2) Because pilots are flying more advance aircrafts they try to take these machines beyond what they are capable of enduring(both manuvering, equipments) hence causes crashes, ground collision, disorientation
3) Pilots treat these planes as old toys, old bikes and u know what we do with old machines. We try to rip them apart just for fun(ripping means doing unnecessary dragging, climbing, g forces etc).
4) Some thing is wrong in the original engines of these aircrafts which is just coming up with time (although no reports for this).
@Oscar @Windjammer