The Air Force said yesterday thet the black box contains two hours of recordings, but not from Wednesday's fatal flight, which killed Socialist candidate Eduardo Campos and six others. It says the reason behind the discrepancy will be investigated.
The statement emphasises that the lack of recordings doesn't doom efforts to find the causes of the accident, saying the black box represents "just one element" of the investigation.
The crash threw Brazil's presidential race into turmoil less than two months ahead of the Oct 4 race. Campos was polling in third place, behind incumbent President Dilma Rousseff.