The investigation report says Air India did not carry out those inspections - prompting speculation that the accident could have been caused by faulty switches being flipped by accident. However, in an internal note seen by the BBC, the FAA has since reiterated its belief that the issue did not compromise safety.

A preliminary report into the tragic Air India 171 crash that killed 260 people has sparked fury from grieving families and pilots alike, as it raises more questions than it does answers