two germanwings flights have been forced to make emergency landings in two days - one over a suspected oil leak and another after a passenger and a cabin crew member fell ill .
the flight , which had 123 passengers and five crew members on board , took off from cologne at 9.55 am local time .
germanwings , a budget unit of german airline lufthansa , has been in the spotlight after one of its planes crashed into a mountain in the french alps last week , killing everyone on board .