Saturday's disaster is the deadliest balloon crash in U.S. history, according to the National Transportation Safety Board, eclipsing a 1993 Colorado accident that killed six.
Investigators said the balloon from Heart of Texas Balloon Rides hit power lines near Lockhart, Texas, caught fire and plummeted to the ground, killing everyone on board.
The tragedy brings the number of deaths in U.S. balloon accidents since 2000 to 37, according to NTSB figures.
By comparison, 728 people died in U.S. commercial and commuter airplane crashes during that same period -- including 232 who died in the 9/11 attacks, according to NTSB statistics. The NTSB also reported 24 fatalities in sightseeing helicopter accidents over the same period.
'No engine to fail'
Jeff Chatterton, who represents the Balloon Federation of America, a nonprofit membership organization aimed at advancing ballooning, calls the crash the "biggest lighter-than-air disaster in North American history, dating back to the Hindenburg."
The fact that we have to go back to that infamous 1937 disaster -- in which an airship caught fire and crashed while docking in New Jersey, killing 36 -- speaks to ballooning's overall safety, Chatterton said.
Ballooning is safe, he said, because it's so simple.
"There's no landing gear to fail. There's no engine to fail," Chatterton said. "There's no fixed wings to have a problem with the flaps. There's no rotor blade spinning over your head." Because none of this equipment exists on balloons, Chatterton said, none of it can cause crashes.
Basically, a hot air balloon is controlled by burners which heat the air inside the balloon's envelope. When the air is heated, it makes the balloon rise.
A pilot steers a balloon by using the wind at different altitudes. If the wind is blowing one direction at one altitude, a pilot will rise or descend to catch that wind in hopes of moving in that direction. Pilots descend by pulling a rip cord, which opens a vent to release hot air from the balloon.
But what if something like a power line looms in a balloon's path? How quickly can a pilot maneuver the balloon -- especially an aircraft that's weighed down with a large gondola filled with people?
"That depends on everything from the size of the burner, the number of burners that you have and the wind conditions at the time," Chatterton said. "It's not as easy as making a blanket statement that one is slow and sluggish and the other one is not. ... It's not as simple as that."
Uninsulated power lines pose a threat to hot air balloons by causing sparks that can burn a balloon's envelope or ignite its fuel tank. Collisions with electrical lines caused deadly balloon crashes in 2008 in New Mexico
and in 2014 in Virginia
, among other accidents.
Investigators to regulators: Do your job
The Texas crash, some 30 miles south of Austin, took place two years after America's top transportation investigators basically told the chief of the Federal Aviation Administration that the FAA wasn't doing its job when it came to commercial hot air balloon safety.
It was all there in black and white in a letter
: The National Transportation Safety Board told the FAA it was "concerned ... of the lack of oversight" because commercial balloon operators aren't held to the same standards as commercial helicopter and airplane operators.
The letter followed several commercial balloon accidents that resulted in injured passengers. One crash was deadly.
Surprisingly, there aren't that many commercial balloon operators.
Including part-time pilots and full-time professionals, the Balloon Federation of America estimates there are somewhere between 150 and 200 commercial hot air balloon operators across North America.
The NTSB said it wants all U.S. balloon operators to have "letters of authorization" which would create a record of regular checks that would verify they're maintaining their equipment, using safety checklists and conducting passenger safety briefings.
Right now, commercial balloon operators don't need those letters of authorization — but commercial helicopter and airplane operators do.
Chopper and plane operators who don't comply with the regulations get their letters pulled by the FAA and legally can't fly passengers.
The Balloon Federation of America says it would be OK with the FAA requiring commercial balloon operators to have similar letters of authorization.
"If the FAA and the NTSB have ways that we can improve the safety of our sport, we look forward to working together with them in order to come up with ways that are better, more accessible and safer for everybody," Chatterton said.