A test fire of SpaceX’s Crew Dragon capsule caught fire Saturday at Cape Canaveral Air Force Station emitting a puff of reddish smoke laced with toxic chemicals seen for miles.
What few knew was just how toxic and potentially deadly that distant cloud could have been if winds had shifted onshore.
The special propellants for the Crew Dragon capsule – designed to carefully supply engine firings during liftoff anomalies and navigate the craft in space – are far more dangerous than those used for the typical launch, according to a report in Florida Today. The hydrazine and nitrogen tetroxide used Saturday are called hypergolic fluids, meaning they react violently when they come in contact with one another. They have been used in rockets and spacecraft for decades because they can be stored over a long period of time and still be reliable.
But they are dangerous to handle.
To prevent any potential exposures to the public, tests like Saturday’s are conducted when prevailing winds point away from population centers.
SpaceX, NASA and the U.S. Air Force have remained tight-lipped on the April 20 incident, offering few details about the fire, which lofted reddish nitrogen tetroxide – sometimes referred to as fuming red nitric acid – into the sky as hundreds watched a surfing festival at nearby Cocoa Beach.
There were no injuries. On Thursday, independent safety advisors said NASA and the company had followed proper test procedures.
“The test site was fully cleared, and all safety protocol was followed,” Patricia Sanders, chair of NASA’s independent Aerospace Safety Advisory Panel, said Thursday during a quarterly meeting. “Both NASA and SpaceX immediately executed mishap plans per the agency and the company guidelines.”
Saturday’s test failure cast a shadow of uncertainty over Elon Musk’s $1 billion project to get humans back to orbit, launching from American soil. The last time that happened was July 2011, when space shuttle Atlantis made its swan song mission. Since then, NASA has been buying seats on Russian-made Soyuz rockets to get astronauts to the International Space Station.
SpaceX is required as part of their permit with the Florida Department of Environmental Protection (DEP) to have a response plan in place in the event of an incident, which the company implemented, DEP officials said.
“The fire department and base personnel responded accordingly,” DEP officials said in a prepared statement. “The facility indicated they were able to fully contain the fire and material to the landing pad area and no other building or areas were affected. At this time, SpaceX is still conducting their investigation into the cause of the incident.”
The company must submit a discovery report to DEP within 15 days with details about the incident, the state agency said.
“The Department will review that report and conduct a site visit, and then determine the next steps in the investigation and what further assessment or cleanup activities may be necessary,” DEP officials said.
SpaceX could not be reached for comment Thursday.
Prepared to Respond
Brevard County Emergency Management works with Cape Canaveral Air Force Station Emergency Management and Kennedy Space Center Emergency Management to respond to launch hazards or concerns, said Don Walker, spokesman for Brevard County.
Emergency Management is activated for every launch and is notified of static fire testing on the Air Force station, Walker said.
“In the case of SpaceX’s anomaly last weekend, there was no public safety threat, both due to wind direction and due to the distance of the incident from public areas,” Walker added.
“If space launches, landings or other on-base activity results in an anomaly that is a public safety threat, Brevard County Emergency Management would use a variety of methods to alert the public to shelter indoors (go inside and stay inside),” Walker said. “These tools include social media, text messaging, AlertBrevard automated call/text/email notifications, and even wireless emergency alerts if appropriate. Information would also be shared immediately with all public safety agencies and 911 centers within the county.”
Mishaps with hydrazine and nitrogen tetroxide have happened before, each offering lessons. Rocket accidents in decades past have evacuated entire towns. And if Saturday’s toxic cloud had reached people, it would have potentially caused severe burns on contact.