Question: when did black boxes get installed in planes
[{'answer': 'by March 1 , 1967', 'provenance': [{'wikipedia_id': '938385', 'title': 'Flight recorder', 'start_paragraph_id': 55, 'start_character': 137, 'end_paragraph_id': 55, 'end_character': 154, 'bleu_score': 1.0, 'section': 'Section::::Regulation.\n'}]}, {'provenance': [{'wikipedia_id': '938385', 'title': 'Flight recorder', 'start_paragraph_id': 55, 'start_character': 0, 'end_paragraph_id': 55, 'end_character': 570, 'bleu_score': 0.865155549807876, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15250006181394675959}, 'section': 'Section::::Regulation.\n'}]}]