SELECT sum(t.traveller_count) as pax                                                                                                                                                  
  FROM (SELECT count(t3.traveller_id) as traveller_count FROM booking t1 INNER JOIN flight t2 ON t1.booking_id = t2.booking_id LEFT JOIN traveller t3 ON t1.booking_id = t3.booking_id
     LEFT JOIN xres_jt_flights.nurflug_rt t4 ON t2.nurflug_rt_id = t4.id LEFT JOIN xres_jt_flights.oneway_pool t5 ON t4.flight_id_outward = t5.flight_id AND t4.from_date =           
     t5.dep_date AND t4.toc = t5.toc                                                                                                                                                  
  WHERE t2.operator = 'AIR' AND t5.offer_id = '13501246' AND t1.`status` = 'OK' AND t3.`type` != 'B'                                                                                  
  GROUP BY t1.booking_id UNION ALL SELECT count(t3.traveller_id) as traveller_count FROM booking t1 INNER JOIN flight t2 ON t1.booking_id = t2.booking_id LEFT JOIN traveller t3 ON   
     t1.booking_id = t3.booking_id LEFT JOIN xres_jt_flights.nurflug_rt t4 ON t2.nurflug_rt_id = t4.id LEFT JOIN xres_jt_flights.oneway_pool t5 ON t4.flight_id_return = t5.flight_id 
     AND t4.to_date = t5.dep_date AND t4.toc = t5.toc WHERE t2.operator = 'AIR' AND t5.offer_id = '13501246' AND t1.`status` = 'OK' AND t3.`type` != 'B' GROUP BY t1.booking_id) t