Story So Far: 13 things you need to know about Malaysia Airlines Flight 17

Malaysia Airlines Flight 17 crashed July 17 in eastern Ukraine, killing all 298 people on board. Here are 13 things you need to know.

Who is responsible for shooting down Malaysia Airlines Flight 17? Full story >

American intelligence agencies think Ukrainian separatists shot down the passenger jet by mistake, possibly after misreading fuzzy radar images on a surface-to-air missile launcher provided by Russia, senior U.S. officials said Tuesday.

President Obama had said Friday that the surface-to-air missile that brought down the aircraft was fired from territory controlled by pro-Russia separatists.

The United States believes they were using a launcher with a rudimentary radar system that was supposed to be hooked up to other radar that would have allowed them to tell the difference between military and civilian planes, U.S. officials said.

The missile that took down the jetliner was probably fired by an "ill-trained crew," said one U.S. official.

U.S. officials have verified recordings from the Ukrainian government of conversations between separatist leaders, which suggest coordination between the separatists and Russian fighters across the border.

Ukraine and Russia have blamed each other for the incident, and Russia has denied any involvement.

A U.S. official told the Associated Press on Saturday that the latest intelligence suggests Russia provided more than one missile system to pro-Russia separatists over the last week or so.

But U.S. officials so far haven't been able to determine the nationalities or identities of the crew that launched the missile, and have not released evidence proving that Russia's military helped train pro-Russia separatists to use the SA-11 missile system.

But they did say Tuesday that the Russian military has been training Ukrainian separatists to operate anti-aircraft weapons at a base in southwestern Russia.

Were any Americans on board? Full story >

Only one U.S. citizen has been identified as a passenger on the crashed Malaysia Airlines jetliner. Quinn Lucas Schansman, a dual Dutch and American citizen, was on the plane en route to meet his family for a vacation, a cousin said.

The cousin said Schansman was born in New York, but had lived in the Netherlands for most of his life. A Facebook page appearing to belong to Schansman indicates that he lived in Amsterdam as of April, and was attending the International Business School at Hogeschool van Amsterdam.

No other Americans have been identified, but an Indiana University graduate student was on the plane when it crashed.

Who else was on the plane? Full story >

A total of 298 people were on board Malaysia Airlines Flight 17: 15 crew members, 280 passengers and three infants.

Some of the passengers were researchers en route to the 20th annual International AIDS Conference in Australia, including prominent researcher Joep Lange, a former president of the International AIDS Society.

The passengers also included a Dutch senator, an Australian nun and a spokesman for the World Health Organization.

Malaysia Airlines officials on Saturday released a complete accounting of the nationalities of those aboard the flight:

What do we know about how many passengers were en route to the AIDS conference in Melbourne? Full story >

Australian newspapers reported Thursday that attendees of the 20th International AIDS Conference in Melbourne had been told about 100 of the passengers aboard Flight 17 were en route to the conference. But those reports appear to have been inaccurate.

So far, organizations have confirmed the names of six passengers with ties to AIDS research.

Among those killed was prominent Dutch researcher Joep Lange, a former president of the International AIDS Society.

Lange was considered “a giant� in the HIV/AIDS research movement and had been working in AIDS research and advocacy since the earliest days of the epidemic.

The other five victims confirmed were Pim de Kuijer of STOP AIDS NOW!; Lucie van Mens, director of AIDS Action Europe; Maria Adriana de Schutter of AIDS Action Europe; Glenn Thomas of the World Health Organization; and Jacqueline van Tongeren of the Amsterdam Institute for Global Health and Development.

On Saturday, organizers of the conference released a statement that named those six individuals.

"The extent of our loss is hard to comprehend or express," said International AIDS Society President Françoise Barré-Sinoussi. "We grieve alongside all of those throughout the world who have lost friends and family in this senseless tragedy."

What brought down the Malaysia Airlines jet? Full story >

Ukrainian officials say the plane was shot down by a Buk missile from territory controlled by pro-Russia separatists, and senior U.S. officials have said they have reached the same preliminary conclusion.

U.S. intelligence agencies have verified photos posted to social media sites last week showing an SA-11 launcher driving toward the Russian border missing at least one missile.

The U.S. ambassador to the United Nations, Samantha Power, said Friday that although Ukrainians do have Buk missiles in their weapons inventory, the United States does not know of any such Ukrainian-owned missiles in the area where the plane was downed.

On Saturday, military experts said taking down an airplane traveling about 600 mph at an altitude of 33,000 feet required vastly more expertise than, say, firing a shoulder-braced rocket-propelled grenade at a slow-moving helicopter. A crew of at least four would have been needed to accurately fire the truck-mounted Russian-made SA-11 missile, also known as a Buk missile system.

Why didn't the plane avoid the missile or call for help?

Malaysian Prime Minister Najib Razak said Thursday that the aircraft did not make a distress call before being shot out of the sky.

Most commercial jets are not outfitted with missile warning and defense systems, which are standard on many military aircraft. So it's unlikely that the Malaysia Airlines pilot would have been aware that the missile's guidance system had locked onto the aircraft.

Was the plane traveling in restricted airspace?

No, but it was close. Aviation and intelligence officials have said Malaysia Airlines Flight 17 was cruising about 1,000 feet above restricted airspace when it was struck.

Because of ongoing violence in the region, including the recent downing of military aircraft, Ukrainian aviation officials had closed the airspace only below 32,000 feet in altitude.

Malaysia Airlines Flight 17 was at about 33,000 feet when it vanished from radar screens, according to European aviation authorities.

Both American and European aviation officials have warned commercial airlines against flying over Crimea since April, but both agencies said that the location where the plane was downed Thursday was outside the warning area.

Shouldn't the airlines have avoided the area anyway? Full story >

Malaysia's transportation minister and Malaysia Airlines have defended the pilots' decision to use the flight path.

At a news conference, Transportation Minister Liow Tiong Lai said Flight 17's path had been approved by the International Civil Aviation Organization, and by the countries that controlled the airspace the plane was set to travel through.

In a statement Friday, Malaysia Airlines also said the flight path had been approved by Eurocontrol, the governing body responsible for flight paths over Europe.

The airline denied wading into airspace that had previously been deemed "risky" by U.S. and European aviation officials. "At no point did MH17 fly into, or request to fly into, this area," the airline said in a statement. "At all times, MH17 was in airspace approved by the ICAO."

Have passenger jets ever been shot down before? Full story >

It is not the first time that commercial jets have been accidentally shot down. A Soviet fighter plane shot down Korean Air Lines Flight 007, carrying 269 people, including a U.S. congressman, in 1983. Five years later, a U.S. Navy warship mistakenly shot down Iran Air Flight 655, carrying 290 people.

Are planes still flying over the area? Full story >

Since the crash, both Eurocontrol and the FAA have barred all flights over the larger eastern Ukraine region.

The FAA has said all U.S. commercial airlines have agreed to avoid the region near the Russia-Ukraine border, and several international carriers have issued statements saying they are steering clear of the area.

When was the flight last in contact, and when did it crash?

Malaysia Airlines Flight 17 was scheduled to leave Amsterdam's Schiphol Airport at 12 p.m. Thursday for Malaysia's Kuala Lumpur International Airport. It actually left at 12:15 p.m., and was due to arrive at 6:10 a.m. the next day.

Ukrainian air traffic control notified Malaysia Airlines about 4:20 p.m. that it had lost contact with Flight 17 about 20 miles from Tamak waypoint, or about 30 miles from the Russia-Ukraine border. The Boeing 777 crashed in the Donetsk region in Ukraine about 4:30 p.m. Thursday.

Who is investigating the crash now? Full story >

The Netherlands, which lost 193 people aboard the plane, will take the lead on the investigation, in conjunction with international air safety organizations, Ukrainian Prime Minister Arseniy Yatseniuk said.

Malaysian Prime Minister Najib Razak announced Monday that he had brokered a deal with pro-Russia separatists to retrieve the plane's black boxes and transport the remains of 282 people by train to northeastern Ukraine, where they would be handed over to Dutch officials.

Separatist leaders handed over the plane’s two black boxes to a Malaysian delegation early Tuesday after several hours of negotiations.

Some of the first international investigators to arrive on scene had trouble accessing the crash site over the weekend. Armed pro-Russia separatists controlling the area continued to limit access of international teams seeking to recover bodies and investigate the crash.

Ukrainian and Malaysian officials have suggested that the integrity of the scene has been compromised.

On Tuesday, international investigators on the scene said it appeared that parts of the plane had been removed and cut into.

In a speech Monday, President Obama said compelling separatists to cooperate with the investigation is the least Russia can do.

The United Nations Security Council unanimously adopted a resolution Monday calling for investigators to have unfettered access to the site.

What is the U.S. doing about the situation in Ukraine?

President Obama called for an immediate cease-fire in eastern Ukraine on Friday, describing the crash as a global tragedy.

The President said that the incident should snap everybody's heads to attention that the conflict in Ukraine has widespread consequences but that he did not see a U.S. military role beyond support for NATO.

A senior official in the Obama administration said officials are already considering hitting Russia with greater sanctions if investigators find that Russia supplied the missile used to down the jetliner.

The official said the administration believes it could persuade other European countries to follow suit if the link is proved.

Lawmakers have echoed those sentiments.

Investigators from the FBI and the U.S. National Transportation Safety Board are among the delegation of international experts who will examine the crash.