Here's what we know about the crash:
• The plane was an Airbus A320 and carried 150 people, according to Germanwings, the budget airline that operated the flight.
• No survivors are expected, French President François Hollande said. He called the incident a "tragedy on our soil."
• One important note: We don't yet know what caused the crash.
• Authorities have recovered one of the plane's black boxes, French Interior Minister Bernard Cazeneuve said.
• In less than 10 minutes, the plane fell from 38,000 feet — its cruising altitude — to 6,000 feet. Then it dropped off radar screens.
• An official passenger list has not yet been released, but reports indicate that the group included 16 students and two teachers from a German high school. Pictures showed memorial offerings at the school.
• The A320 went down in southern France. The terrain is rugged, and Hollande has said that the crash "happened in a very difficult to access zone."
• The flight was operated by Germanwings, which is run by Lufthansa.
• According to Airbus, the A320 that crashed Tuesday was "delivered to Lufthansa from the production line in 1991. The aircraft had accumulated approximately 58,300 flight hours in some 46,700 flights. It was powered by CFM 56-5A1 engines. At this time no further factual information is available."
The A320 plane is a workhorse of modern aviation. Similar to the Boeing 737, the single-aisle, twin-engine jet is used to connect cities between one and five hours apart. Worldwide, 3,606 A320s are in operation, according to Airbus. The A320 is certified to fly up to 39,000 feet but it can begin to experience problems as low as 37,000 feet, depending on temperature and weight, including fuel, cargo and passengers.
• Richard Aboulafia, an aviation expert with Teal Group Corp, discussed the Airbus A320's safety record with The Washington Post, saying: "In terms of accident rates, it's one of the safest jets built. There are no reasons to question its record." Read the full post here.
• Here's something else noted in that post: "The jet's last major inspection was in 2013, though a regular check of the plane was conducted on Monday, the day before the crash, Germanwings officials said."
• Two opera singers are believed to be among the passengers, the AP reported. A Spanish opera house told the wire service that Maria Radner was on the plane, and an opera house in Germany said that Oleg Bryjak had also taken the flight.
More images from Tuesday:
[Anthony Faiola contributed to this report, which has been updated.]