Based in Barcelona, the airline explained that it performs the so-called “reversal” flights to Granada, meaning the flight attendants and pilots stay on board the aircraft for a short break before flying back to Barcelona.
Vueling does not have a flight attendant base in Granada, so when two flight attendants became ill before their flight, they the airline didn't have anyone local to call to replace those who were out of service.
Where is the connection between the 50 passengers left behind and the flight attendants?
Why did the airline have to leave customers in Granada?
The minimum crew size in Spain is controlled by the European Aviation Safety Agency EASA, and in the case of the Airbus A320 used by Vueling on this flight, the rules require a minimum of four cabin crew.
Due to the loss of two crew members, Vueling is unable to it was a legitimate opportunity to make the return flight. However, Vueling found a way out of the impasse. They managed to find a spare flight attendant in Malaga, and he urgently flew to Granada on a scheduled flight.
EASA allows airlines to operate the A320 with a reduced crew of three flight attendants for unforeseen circumstances – for example, due to illness of the crew to return the aircraft to the base airport, but the number of passengers on board must be reduced.
Vueling VY2017 passengers on Tuesday experienced this “lottery” 50 of them stayed in Granada in order for the airline to meet EASA minimum crew requirements.
In fact, these kinds of situations are more common than you might think. This is especially true on short haul flights, where airlines rarely take flight attendants “with a margin”, that is, more than the minimum required number.
When operating flights from the home, that is, the base airport, it is not legally allowed to reduce the standard minimum crew size, but it is not uncommon for this to happen on flights returning to base.
In some cases, airlines have enough time to “persuade” flight attendant to join the flight or “cure” her, although, as in the case of Tuesday, this is not always possible.
Are passengers entitled to compensation under European rules if they are removed from a flight due to illness of the crew? Apparently, yes. Airlines have to assume that someone might someday get sick, and European courts have long ruled that these sorts of situations do not qualify as “extraordinary circumstances.”