Airlines have been urged to keep a close eye on capacity next year as the industry fights to remain profitable.
Speaking to more than 800 delegates at the Association of Corporate Travel Executives (ACTE) global education conference in Berlin this week, Marie-Joseph Male, managing director of airline alliance Skyteam, said a return to over capacity was one of the main risks to airlines' continued profitability in 2011.
Over capacity has blighted the sector for years, and the recession forced a number of companies to ground aircraft to bring supply back in line with demand simply in order to survive.
It was a struggle for almost every carrier and resulted in the loss many jobs, but most were able to get their fleets in order.
Male quoted Iata's recently amended forecast, which predicted airlines worldwide would make a collective profit of $8.9 billion this year.
But said in order for the trend to continue over the subsequent 12 months, airline bosses would have to be on their toes.
He said: "The airline business is, to a large extent, linked to the economy. Iata's forecast is good news. But Europe remains in the red. We have to approach 2011 with the same cautious optimism as we still face risk in certain areas.
"Excess capacity, which has been managed well until now, runs the risk of imbalance in 2011."
Male said labour costs, taxes and oil prices would also play part of the financial precariousness to be endured by all airlines next year.