A large contingent of students from Zhejiang province in China was traveling to the United States to spend a couple of weeks seeing part of America and learning English. Such groups represent the ideal of modern commercial aviation: the kind of educational and cultural exchange on which these students were embarking—nearly unthinkable a generation ago—is something the airline industry now enables on a commonplace basis.

However, the July trip ended in tragedy for three of the students, all teen-aged girls. The Asiana Airlines Boeing 777-200ER on which they were flying attempted to make what should have been a routine landing on a clear day at San Francisco International Airport. The twin-aisle jet came down short of SFO’s runway 28L, hit a sea wall and crashed on landing, killing the three Chinese students and severely injuring a number of others.

We emphasize the fatalities to strongly caution the aviation community against too easily falling back on the comfort of recent years’ record safety numbers.

In 2012, none of IATA’s 240 member airlines had a Western-built jet hull loss. Before the July 6 777 accident, there hadn’t been a fatal mainline commercial jet crash on US soil since November 2001. And an extraordinary element of the Asiana crash was how many survived; a good portion of the 307 passengers and crew literally walked away from the fiery scene with little or no injuries (thanks in part to efforts over the last couple of decades to strengthen aircraft, add numerous onboard safety redundancies and train flight crews to quickly evacuate passengers).

But the loss of lives during what should have been a routine part of a routine flight should give the world’s airlines, airports and aircraft manufacturers pause.

This was a first-rate airline operating a top-of-the-line jet with modern avionics between two of the world’s premier international airports, Seoul Incheon and San Francisco. The cockpit crew was very experienced. Yet the US National Transportation Safety Board has determined that the pilots did not realize until just 100 feet before impact that the aircraft had dropped significantly below its target speed.

Ascertaining precisely what went on in the cockpit during the descent will be part of the board’s ongoing inquiry. “This is just the tip of the iceberg,” NTSB chairman Deborah Hersman said in her last on-site briefing from San Francisco on the crash. That’s quite a statement given the large trove of information the board has already uncovered: the 777’s cockpit voice recorder and flight data recorder were easily recovered and the pilots have been interviewed by investigators.

It is critical to find out exactly what went wrong with Asiana Flight 214, and learn as much as possible from the accident and its aftermath. Achieving absolute 100% safety in commercial aviation may not be possible—but this crash should not have happened.