Since 2008, around 16 million cars with Takata air bags have been recalled worldwide, with more than 10 million of those in the United States.
Takata indespensible—for now
Another question, particularly for drivers, is how quickly Takata can supply replacement parts.
In filings with NHTSA on Wednesday, automakers including Honda and Toyota said they were looking into the option of getting air bag inflators from other companies, but most said that would take too long. BMW is backing Takata's efforts to shift inflator production to Germany from Mexico, and said it was not looking elsewhere for supply as it would take two years to approve a new source.
Takata recently told analysts it had enough existing and planned capacity to make replacement parts—but that doesn't factor in a nationwide recall. Reuters calculations show it could take five months to make just 1 million inflators on two new production lines planned in Mexico from January, assuming work around-the-clock five days a week.
Takata has set aside 77.5 billion yen ($660 million) for recall costs since last year to cover about 9 million vehicles, fewer than the number of cars recalled since 2013.
"The American people deserve to know the whole story behind this air bag recall," Senator Bill Nelson, a Democrat from Florida who will chair the congressional hearing, said on Wednesday. "That's why we're holding this hearing to get them some answers and spur automakers to do more to help get these dangerous cars off the road and fixed as soon as possible."
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Thursday's witness list includes Hiroshi Shimizu, senior vice president of global quality assurance at Takata; Scott Kunselman, Chrysler's senior vice president of vehicle safety and regulatory compliance, Rick Schostek, executive vice president of Honda North America, and Stephanie Erdman, a victim of Takata's air bag defect.
David Friedman, NHTSA's deputy administrator, will answer to criticism his agency has been slow to respond to the scandal.
NHTSA agreed in June to allow automakers to do a regional recall and use their discretion in deciding how and when to notify customers and replace faulty parts, resulting in confusion for car owners receiving mixed messages.
President Barack Obama said on Wednesday he was nominating Mark Rosekind, an expert in human fatigue, as the next head of NHTSA.