The local "Tagesspiegel" newspaper reported Thursday that the city's construction authority has demanded additional changes to an ongoing planning permit process for the smoke extraction system, a problem which has plagued the airport since at least 2011, when the second opening date was pushed back.

The construction authority said planning permission would certainly be needed for the latest alterations to the system. According to the "Tagesspiegel," the new application was submitted by the Berlin Brandenburg Airport (FBB) at the end of February and covered some 10,000 pages, or 50 box files.

This is not unusual for a complex project that is expected to cost several billion euros. For instance, the application documents must include proof that the smoke extraction system will work in any possible scenario. According to the construction authority, the airport only covered 175 of 188 scenarios it set out. Drawing up plans to cover the remaining 13 scenarios is likely to take several weeks.

Mindboggling complexity

That in itself is still progress, however, considering that before the last postponed opening date, in 2012, the smoke extraction system was considered unworkable.

Nevertheless, this latest setback is likely to delay the final opening, since in order to meet the deadline of the second half of 2017, all construction work was supposed to have been completed this month. Some 15 months have been set aside purely for testing all the myriad systems in the airport.

Despite the new report, the German government is sticking to previous statements about the completion dates. "The statement made by the FBB leadership is still valid, which foresees operation to begin in the second half of 2017," a transport ministry spokesman said, before applying subtle pressure on the airport chiefs: "We expect the management of the airport to fulfill their own statements when it comes to the opening. We have no other information."

Following pressure from the government, which is co-financing the project, Berlin Mayor Michael Müller has been forced to call a special meeting of the airport committee for this Friday, which will be attended by BER chief Karsten Mühlenfeld.

Nostalgia petition

Last week, the chief BER technician Jörg Marks made bullish statements against the mockery that the airport has attracted in the nation's capital. "We need an uprising of the decent people who want this project finished," he said at a public event. "This airport is without alternative." The phrases he chose were fairly pointed, considering that they referenced statements made during political crises by Chancellor Angela Merkel and her predecessor Gerhard Schröder.

Marks also reiterated that the current "achievable" opening date was October 2017 - the point at which most airports switch to their winter schedules. Should the date have to be pushed back again, the public announcement would have to come by October this year, since Mühlenfeld has promised that airlines and other businesses using the new airport would be given a year's notice to prepare.

The costs of the new airport have exploded, even beyond the normal standards for major long-term infrastructure projects on this scale - originally calculated at 2.5 billion euros ($2.7 billion), they have now swelled to 6.6 billion euros. Meanwhile, estimates for how much the incomplete airport costs to maintain fluctuate between six and 17 million euros a month.

The people of Berlin are sticking to their tradition of nostalgia for their doomed airports. A popular campaign and a referendum to keep Tempelhof airport open failed in 2008, before it was turned into a park (and more recently a refugee shelter). Now, a petition has been launched to save Tegel airport, one of the two airports set to be replaced by BER.

Some 18,000 signatures have been collected in three months, with only 20,000 needed by June. Once that target is reached, which seems likely, the second phase would be launched in September: if the new petition collects 175,000 signatures, the question of keeping Tegel open would have to go a referendum as well.