What the ‘black box’ can tell us about plane crashes

NEW DELHI (AP) — A preliminary finding into last month’s Air India plane crash has suggested the aircraft’s fuel control switches were turned off, starving the engines of fuel and causing a loss of engine thrust shortly after takeoff.

The report, issued by India’s Aircraft Accident Investigation Bureau on Saturday, also found that one pilot was heard on the cockpit voice recorder asking the other why he cut off the fuel in the flight’s final moment. The other pilot replied he did not do so.

The Air India flight — a Boeing 787-8 Dreamliner — crashed on June 12 and killed at least 260 people, including 19 on the ground, in the northwestern city of Ahmedabad. Only one passenger survived the crash, which is one of India’s worst aviation disasters.

The report based its finding on the data recovered from the plane’s black boxes — combined cockpit voice recorders and flight data recorders.

Here is an explanation of what black boxes are and what they can do:

The cockpit voice recorder and the flight data recorder are tools that help investigators reconstruct the events that lead up to a plane crash.

They’re orange in color to make them easier to find in wreckage, sometimes at great ocean depths. They’re usually installed a plane’s tail section, which is considered the most survivable part of the aircraft, according to the National Transportation Safety Board's website.

The cockpit voice recorder collects radio transmissions and sounds such as the pilot’s voices and engine noises, according to the NTSB’s website.

Depending on what happened, investigators may pay close attention to the engine noise, stall warnings and other clicks and pops, the NTSB said. And from those sounds, investigators can often determine engine speed and the failure of some systems.

Investigators can also listen to conversations between the pilots and crew and communications with air traffic control. Experts make a meticulous transcript of the voice recording, which can take up to a week.

The flight data recorder monitors a plane’s altitude, airspeed and heading, according to the NTSB. Those factors are among at least 88 parameters that newly built planes must monitor.

Some can collect the status of more than 1,000 other characteristics, from a wing’s flap position to the smoke alarms. The NTSB said it can generate a computer animated video reconstruction of the flight from the information collected.

At least two people have been credited with creating devices that record what happens on an airplane.

One is French aviation engineer François Hussenot. In the 1930s, he found a way to record a plane’s speed, altitude and other parameters onto photographic film, according to the website for European plane-maker Airbus.

In the 1950s, Australian scientist David Warren came up with the idea for the cockpit voice recorder, according to his 2010 AP obituary.

Warren had been investigating the crash of the world’s first commercial jet airliner, the Comet, in 1953, and thought it would be helpful for airline accident investigators to have a recording of voices in the cockpit, the Australian Department of Defence said in a statement after his death.

Warren designed and constructed a prototype in 1956. But it took several years before officials understood just how valuable the device could be and began installing them in commercial airlines worldwide.

Some have suggested that it stems from Hussenot’s device because it used film and “ran continuously in a light-tight box, hence the name ‘black box,’” according to Airbus, which noted that orange was the box’s chosen color from the beginning to make it easy to find.

Other theories include the boxes turning black when they get charred in a crash, the Smithsonian Magazine wrote in 2019.

The media continues to use the term, the magazine wrote, “because of the sense of mystery it conveys in the aftermath of an air disaster.”

FILE -The tail of the airplane is seen stuck in a building at the site of an airplane that crashed in India's northwestern city of Ahmedabad in Gujarat state, June 12, 2025. (AP Photo/Ajit Solanki, File)

A policeman walks past buildings damaged in the June 12 Air India plane crash in Ahmedabad, India, Saturday, July 12, 2025. (AP Photo/Ajit Solanki)

People offer prayers for crew members of the Air India flight that crashed in Ahmedabad last month during a prayer meeting at a church in Mumbai, India, Saturday, July 12, 2025. (AP Photo/ Rafiq Maqbool)

A relative of the crew of the Air India flight that crashed in Ahmedabad last month, mourns during a prayer meeting at a church in Mumbai, India, Saturday, July 12, 2025. (AP Photo/ Rafiq Maqbool)

A woman offers tribute to the crew members of the Air India flight that crashed in Ahmedabad last month during a prayer meeting at a church in Mumbai, India, Saturday, July 12, 2025. (AP Photo/ Rafiq Maqbool)

Mother of Clive Kunder, co-pilot of the Air India flight that crashed in Ahmedabad last month, mourns during a prayer meeting for the Air India crew, at a church in Mumbai, India, Saturday, July 12, 2025. (AP Photo/ Rafiq Maqbool)

A man offer prayers for crew members of Air India flight that crashed in Ahmedabad last month during a prayer meeting at a church in Mumbai, India, Saturday, July 12, 2025. (AP Photo/ Rafiq Maqbool)

People offer prayers for crew members of the Air India flight that crashed in Ahmedabad last month during a prayer meeting at a church in Mumbai, India, Saturday, July 12, 2025. (AP Photo/ Rafiq Maqbool)

BROADVIEW, Ill. (AP) — Four Illinois Democrats toured a federal immigration center outside Chicago on Monday, the latest members of Congress allowed inside immigration facilities after a judge last week lifted Trump administration limits on lawmaker visits.

Six months after they were denied access, U.S. Reps. Danny Davis, Delia Ramirez, Jonathan Jackson and Jesús “Chuy” Garcia entered the immigration processing center in suburban Broadview. The U.S. Immigration and Customs Enforcement facility, criticized as a de facto detention center with inhumane conditions, has been at the forefront of an immigration crackdown resulting in more than 4,000 arrests in the Chicago area.

The Associated Press observed the lawmakers enter the boarded-up brick building after talking to a masked official at the door and then leave about an hour later.

“We wanted to test whether or not there would be a violation of a court order reaffirming that we have the right to be here at any time for any reason, without advance notice,” Garcia said afterward.

A federal judge last week temporarily blocked the Trump administration from enforcing policies that limit congressional visits to immigration facilities. The ruling stems from a lawsuit filed by 12 members of Congress who sued in Washington, D.C. to challenge ICE’s amended visitor policies after they were denied entry to detention facilities.

After their visit, the Illinois lawmakers reported that Monday seemed like an atypical day with only two people in custody. A day earlier there had been 20, according to Garcia.

During the height of the immigration crackdown dubbed “Operation Midway Blitz,” more than 150 people were held at the facility, many for several days at a time, according to congressmen, attorneys and activists. Conditions at the center, where immigrants are processed for detention or deportation, prompted numerous complaints, a lawsuit and a court-ordered visit by a judge. Illinois does not have an immigration detention center.

Since then, immigration officials have said they've made changes and those held at the Broadview center have access to hot meals and legal counsel, among other things. ICE has rejected claims that the processing center is used for detention.

While the Illinois Democrats noted improvements, they raised concerns about toilets without adequate privacy, few showers, and no medical staff on site.

“This visit will not end our responsibility. We will follow up,” Jackson said. “We will be back and we’ll demand answers.”

Ramirez said not having a medical professional nearby was troubling, especially after the death of a 56-year-old man found unresponsive at an ICE facility in Michigan. Nenko Gantchev of Bulgaria was arrested in the Chicago area crackdown. ICE officials said it appeared he died of natural causes on Dec. 15, but the official cause remained under investigation.

Since the ruling, House members elsewhere have also visited ICE facilities.

U.S. Rep. Raja Krishnamoorthi, an Illinois Democrat, gained access to the Broadview facility on Friday and reported the practice of holding people overnight seemed to have ended for the time being. He said he had tried multiple times to visit over the past few months.

In California, U.S. Rep. Jimmy Gomez visited a federal immigration facility in downtown Los Angeles on Friday. The Democrat, among the 12 lawmakers who sued, said there was no working kitchen, no on-site medical staff and limited food options, according to a statement.

In New York, U.S. Reps. Dan Goldman and Adriano Espaillat, both Democrats who also sued, visited an ICE holding facility on Friday at 26 Federal Plaza in New York City. In a joint statement, the congressmen said immigrants were being held for as long as three days without access to showers and proper beds.

“The Trump administration’s obsession with hitting an arbitrary — and unrealistic — number of deportations is creating a humanitarian crisis,” Espaillat said.

In Illinois, the Trump administration has kept strict controls on access to the Broadview facility, barring attorneys, family members of those arrested and journalists. At one point federal authorities built a fence around the building as protests grew and clashes with federal agents intensified.

Separately, U.S. Rep. Lauren Underwood of Illinois said she was allowed to visit the Broadview facility late last month. Underwood, a Democratic member of the Homeland Security Subcommittee on Appropriations, raised concerns about conditions, staffing and record keeping. She said no arrestees were present during her visit “due to a scheduled security system video camera update.”

A message left Monday for ICE wasn't immediately returned.

Four Illinois members of Congress left to right; Rep. Danny Davis, D-Ill., Jesus Garcia, D-Ill., Rep. Delia Ramirez, D-Ill., Rep. Jonathan Jackson, D-Ill., prepare to enter the U.S. Immigration and Customs Enforcement processing center Monday, Dec. 22, 2025, in Broadview, Ill. (AP Photo/Sophia Tareen)

Four Illinois members of Congress left to right; Rep. Jonathan Jackson, D-Ill., Rep. Delia Ramirez, D-Ill., Jesus Garcia, D-Ill., and Rep. Danny Davis, D-Ill., prepare to enter the U.S. Immigration and Customs Enforcement processing center Monday, Dec. 22, 2025, in Broadview, Ill. (AP Photo/Sophia Tareen)

Four Illinois members of Congress Rep. Danny Davis, D-Ill., Jesus Garcia, D-Ill., Rep. Delia Ramirez, D-Ill., Rep. Jonathan Jackson, D-Ill., enter the U.S. Immigration and Customs Enforcement processing center Monday, Dec. 22, 2025, in Broadview, Ill. (AP Photo/Sophia Tareen)

Four Illinois members of Congress left to right; Rep. Jonathan Jackson, D-Ill., Rep. Delia Ramirez, D-Ill., Jesus Garcia, D-Ill., and Rep. Danny Davis, D-Ill., are allowed to enter the U.S. Immigration and Customs Enforcement processing center Monday, Dec. 22, 2025, in Broadview, Ill. (AP Photo/Sophia Tareen)

Four Illinois members of Congress left to right; Rep. Jonathan Jackson, D-Ill., Rep. Delia Ramirez, D-Ill., Rep. Danny Davis, D-Ill., and Jesus Garcia, D-Ill., leave after a visit to the U.S. Immigration and Customs Enforcement processing center in Broadview, Ill. (AP Photo/Sophia Tareen)