SAO PAULO (Reuters) - Brazilian airlines are enjoying a boost as fans from all over the country fly to Rio de Janeiro ahead of a free Lady Gaga concert that is expected to draw more than 1 million fans to Copacabana Beach this weekend.

The 39-year-old "Die with a Smile" and "Poker Face" singer from New York will take the stage at the famous beach on Saturday as part of Rio's efforts to bring superstars to perform at free events that authorities say lift the local economy.

The country's largest carriers - the local unit of Chile's LATAM Airlines, Gol and Azul ( AZUL ) - all reported on Friday that they have been operating more flights that are close to full.

LATAM said in a statement that between Wednesday and Monday it had increased the frequency of its flights to Rio's two main airports, Galeao and Santos Dumont, by 25% compared to the previous week, while offering 26% more seats.

"Passenger demand justifies the investments," said the carrier, which is also a sponsor of the concert, noting that on Wednesday and Thursday its flights from Brazilian cities to Rio de Janeiro were 90% full, a measurement known as the load factor.

That is higher than the 80.8% load factor LATAM registered in domestic routes in the first quarter.

Rio de Janeiro's city government estimates that 1.6 million people will attend the concert, Gaga's first in Brazil since 2012, with attendance also boosted by a long weekend as the South American country celebrated Workers' Day on Thursday.

Azul ( AZUL ) in a statement said the load factor of its operations to Rio this week hit 91%, while Gol said it had added 60 flights to Galeao airport from other major Brazilian cities.

The free open-air concerts, whose lineup also included Madonna last May, are providing a much-needed boost after a drastic reduction in recent years in the number of flights to Rio while the city grappled with an economic crisis.

"Music tourism is the darling of the moment in Brazil," Tourism Minister Celso Sabino said. "People are traveling more and more to see concerts and festivals. This boosts the entire tourism industry, from hotels to coconut water stalls."