Over the next ten days, the team at nine.com.au will be looking back at ten stories that shaped the decade in Australia - from same-sex marriage to the Lindt Cafe siege and everything in between. We start today with two air disasters that will forever be etched into the memories of all Australians.

Thirty-three Australians were tragically killed in two air disasters which shrouded 2014 and the years which have followed in sadness, anger and frustration.

Both incidents, which left a total of 537 passengers dead, forever seared the flight code of Malaysia Airlines into the consciousness of Australians.

What happened to Malaysia Airlines Flight 370 , or MH370 , remains perhaps the greatest mystery of aviation and the subject of intense speculation.

The flight path of MH370 and a path plotted by pilot Zaharie Ahmad Shah (Nine)

Of the 227 passengers, six were Australians. On the morning of March 8, they boarded the Boeing 777-200ER aircraft in Kuala Lumpur, Malaysia, and expected to step off in Beijing, China. The plane never arrived, and the search for the missing jet became the most costly in aviation history. The most likely scenario involved someone in the cockpit of Flight 370, probably Captain Zaharie Ahmad Shah, re-programming the aircraft's autopilot to travel south across the Indian Ocean.

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The downing of Malaysia Airlines MH17 , just four months later, appeared far more clear cut.

After a year-long investigation, Dutch officials pointed the finger of blame at Moscow. It was a Russian surface-to-air missile that hit the Boeing 777-200ER, and sent it crashing to the ground in eastern Ukraine, investigators said. All 283 passengers and 15 crew were killed, including 27 Australians.

Malaysia Airlines Flight MH17 was shot out of the sky over Ukraine on July 17, killing all 298 people onboard. It took almost five years for anyone to be identified as a suspect. Russia condemned the international investigation when former Russian military officers were named. (Getty)

The impact

A total of 33 Australians were needlessly killed in two air disasters in quick succession.

As a nation, we grieved as the stories of those who died emerged from the tragedy.

In the MH17 disaster, the lives of Perth parents Anthony Maslin and Marite "Rin" Norris were ripped apart in the most devastating way.

They lost their three children – Mo, 12, Evie, 10 and Otis, 8 – and Ms Norris' father, Anthony, when the jet was shot down. Their three children had been returning home to Perth for school, while they had stayed behind in Amsterdam.

Mo, Evie and Otis Maslin, who were killed on flight MH17 when their plane was shot down over Ukraine after returning from a holiday to Amsterdam. (AAP)

Did Captain Zaharie Ahmad Shah deliberately fly MH370 into the ocean? Picture: 60 Minutes (60 Minutes)

Why it matters

A nation of great travellers, Australians want to feel safe as we journey abroad. But there were also broader implications in both stories.

MH17 threw the spotlight on Moscow's intervention in the Ukraine and its likely hand in the disaster, despite denials.

What happened in the cockpit of MH370 continues to intrigue. A picture began to emerge of Captain Zaharie's mental health. Had Malaysia Airlines done enough not only to support a troubled pilot, but also spot the warning signs of an employee struggling with mental illness?

Malaysia Airlines came under intense pressure over its investigation. The carrier and Malaysian government were accused by families of MH370 victims of obscuring the truth. When disasters strike, people need and expect clarity from leaders and those in power.

Supplied image obtained Thursday, Sept. 15, 2016 of a large piece of aircraft debris discovered on the island of Pemba, off the coast of Tanzania, in June. Malaysian officials have confirmed the piece as belonging to the missing Malaysian Airlines jet MH370. (AAP Image/Australian Transport Safety Bureau) NO ARCHIVING, EDITORIAL USE ONLY (Supplied)

What's changed

Four suspects have been charged with murdering 298 people onboard MH17. They will be tried in absentia when the case begins in the Netherlands in March 2020.

Family members of victims are pushing for international law changes which will oblige countries embroiled in civil wars to close their airspace.

In the modern age, it was unthinkable a plane like MH370 could simply disappear. In 2016, a new aviation standard meant all aircraft over open ocean report their position every 15 minutes. The 30-day battery life of a plane's underwater locator beacons has also been increased to 90 days, beginning 2020.