Brazil's deepening aviation crisis
A Brazilian passenger plane carrying 176 people crashed on Tuesday in what could be Brazil's deadliest air crash.
Here are key facts about Brazil's deepening aviation crisis over the past year.
Sept 29, 2006: All 154 people on board a Boeing 737-800 owned by low-cost airline Gol Linhas Aereas Inteligentes are killed when it crashes in the Amazon after colliding with a corporate jet in Brazil's worst air crash.
Nov 1: Air traffic controllers, saying they were unduly blamed for putting the two planes on a collision course, stage work slowdowns to protest strenuous labor conditions and low salaries. An agreement to end the protest is reached two days later.
Dec 6: Irate passengers across the country march on landing strips and fights break out in several airports as passengers head to the holiday season and flight delays and cancellations mount.
Dec 22: Government orders air force transport planes to ferry civilians as Brazil's largest airline, TAM Linhas Aereas, abruptly grounds six airplanes during the peak travel season.
Feb 8, 2007: Brazil's airport authority says it will overhaul the main runway at Sao Paulo's Congonhas airport, the country's busiest, after officials try to ban wide-body jets because of fears they could skid off its short landing strips.
Mar 30: The authority suspends all departures across the country after about 100 air traffic controllers walk off the job over work conditions and equipment safety concerns.
Apr 4: The government, facing chaos in air travel, revives a plan to build a high-speed train line between Brazil's two biggest cities, Sao Paulo and Rio de Janeiro.
Jun 25: President Luiz Inacio Lula da Silva says travel order was restored after the government sacked 14 air traffic controllers and ordered two of their leaders arrested. A work slowdown by controllers causes six days of flight delays and cancellations.