<Tr> <Td> Administrator of the National Aeronautics and Space Administration </Td> <Td> Glenn (John Pankow) </Td> <Td> 2013--</Td> </Tr> <Tr> <Td> Chairman of the National Transportation Safety Board </Td> <Td> Humphrey Nelson (Alfredo Narciso) </Td> <Td> 2013--</Td> </Tr> <Table> <Tr> <Th_colspan="2"> Season </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> </Tr> <Tr> <Th> First aired </Th> <Th> Last aired </Th> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 22 </Td> <Td_colspan="1"> September 21, 2014 (2014 - 09 - 21) </Td> <Td> May 3, 2015 (2015 - 05 - 03) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 23 </Td> <Td_colspan="1"> October 4, 2015 (2015 - 10 - 04) </Td> <Td> May 8, 2016 (2016 - 05 - 08) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 23 </Td> <Td_colspan="1"> October 2, 2016 (2016 - 10 - 02) </Td> <Td> May 21, 2017 (2017 - 05 - 21) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> TBA </Td> <Td_colspan="1"> October 8, 2017 (2017 - 10 - 08) </Td> <Td> TBA </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Season </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> </Tr>

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