It’s been just over a year since Ukraine International Airlines Flight 752 was shot down by Iranian missiles. The international investigators probing the incident say they’re still waiting for Iran to provide answers that would help make the skies — especially over conflict zones — safer.

Someone caught video on their cell phone of a fireball in the sky just before dawn on January 8 last year. Then, in the light of day, the wreckage and human remains could be seen strewn across fields in an outer suburb of the Iranian capital, Tehran.

Iran cleared the debris quickly, but it took officials three days to admit that two of its missiles had shot the plane down, by mistake, killing all 176 people on board.

Protests in Iran over regime downing plane 07:59

For the victims’ families there was shock, followed by grief, and then the burning question: What was the civilian airliner doing there in the first place?

Clear and present danger?

One year ago, Iran and the U.S. were on the brink of war. Only hours before the shoot-down, Iran had fired missiles at U.S. bases in neighboring Iraq.

The world was holding its breath, waiting to see if America would retaliate. The U.S. Federal Aviation Administration ordered all U.S. planes to steer clear of the area, which should have been a huge red flag to all airlines around the world.

Inside an Iraqi air base attacked by Iran 01:41

Some did pay attention and diverted their flights away from Iranian and Iraqi airspace. But Ukrainian International Airlines and seven other companies did not. In all, nine planes took off from Tehran’s airport that morning.

But what pilot in his or her right mind would have been in that airspace at that time? Air crash investigator Andrew Blackie says pilots focus on practicalities, not geopolitics.

“You’re provided with information, often pages and pages of information, about navigation aids that aren’t working. Often there are pages of warnings about areas you’re not supposed to fly over,” he tells CBS News. “But it’s very difficult for them… to then think of these more strategic risks.”

It’s up to a country to close its own air space if it’s considered dangerous, but, especially if the military is involved, that won’t necessarily happen. And that can have tragic consequences.

Ralph Goodale, who heads up Canada’s inquiry into the Ukrainian airline crash, says his team is still waiting for “many” answers from Tehran, including on “the decision making process… the risk assessment done by Iran itself to determine whether or not that airspace should [have been] open.”

This date, January 8th, is dedicated by the Govt of Cda to commemorate all victims of air disasters, including Ethiopian Airlines Flight 302 and Air India Flight 182, in addition to Ukraine International Airlines Flight 752. We remember all those lost with love and respect.

— Ralph Goodale (@RalphGoodale) January 9, 2021

If there was a “conscious decision” by Iranian authorities to keep their airspace open, Goodale says his team wants to know what they did “to let airline operators know that there was missile activity going on in the neighborhood… to what extent did Iran notify the airline operators that that that risk existed while they kept the airspace open?”

Finally, he said his investigation wants to know what Iranian military authorities did, if anything, to ensure their air defense units in the area were made aware of the identity of civilian aircraft cleared for landing or take-off from Tehran’s airport.

“Those are three fundamental questions that that I think lie at the very heart of what went on that fateful morning one year ago,” he says.

A tragic history  

Similar questions have been asked before, with other military forces — including the United States’ own — at the heart of investigations.

  • History of civilian airliners downed by military forces 

60 Minutes producer explains MH17 story 02:30

Malaysia Airlines Flight 17 was blown out of the sky in 2014 by Russian-backed militias over a civil war zone in Ukraine.

In 1988, amid soaring tensions in the Persian Gulf, an American warship, the USS Vincennes, shot down Iran Air Flight 655.

Year after Ukrainian plane downed by Iran, civilian airliners are still at risk
Iranian children throw flowers into the sea as they commemorate the 24th anniversary of the downing of Iran Air Flight 655 by the U.S. Navy, at the port of Bandar Abbas, Iran, July 2, 2012. ATTA KENARE/AFP/Getty

Just five years before that, during the Cold War, a Soviet warplane shot down Korean Air Flight 007 after it strayed off course.

A higher power?

The string of unintended disasters has led many to wonder if the decision to close airspace should fall to a higher, supranational authority.

“There are a lot of people that think that would be a good idea,” Goodale tells CBS News. “The problem is you run smack into the sovereignty of states.”

In other words, no country would readily accept having its airspace shut down by an outside power.

There is no way to make the skies over war zones 100% safe, but Goodale says a system of international information-sharing that enables countries to easily and formally warn each other, and their respective airlines, of common danger, would help.

“If you fail to do that, if you balk or fall short,” warns Goodale, “then the reality is the risk continues and, in future, this will happen again.”