Germanwings Flight 9525, which was flying from Barcelona to Düsseldorf, crashed in the French Alps Tuesday morning. There were 150 people on board, comprised of 144 passengers and 6 crew members. As of now, all passengers are feared dead.

As we write this news update, there’s a lot we don’t know about the crash, and investigators, as well as French officials, will be traveling to the site to assess the extent of the damage.

But there are a few things we do know.

Germanwings is a low-cost branch of Lufthansa, but low-cost does not mean that it is unsafe. In fact, the airline has a very good safety record.

The plane was an Airbus 320, which is the most popular plane in Europe. Some question the age of the vessel, but the age doesn’t matter—maintenance matters.

Here’s what the investigators will be asking: When did the plane last have safety checks? When did it undergo maintenance? What issues were documented? Were those items addressed?

Investigators will also be searching for the black box. While the debris field covers two square kilometers, the fact that it’s pinpointed means finding the black box is likely. Then the investigators can uncover exactly what happened in the air.

Watch my report for CBS News to learn more about the tragic crash of Germanwings Flight 9525.

Have some concerns about flight safety? Check out:

• What Are the Safest Airlines in the World?
• Flight Anxiety After 2014 Air Disasters: One Pilot’s Opinion
• What Does AirAsia Flight 8501 Mean for Travel Safety?
• Is It Safe to Fly? The Answer Might Surprise You

By Peter Greenberg for PeterGreenberg.com