Mitch McConnell's billionaire shipping mogul sister-in-law drowned after making fatal mistake in her Tesla: Angela Chao's final moments are revealed including desperate phone call for help after partying with girlfriends on her Texas ranch

Angela Chao, a billionaire shipping industry CEO and sister-in-law to Senate Minority Leader Mitch McConnell, drowned in a pond at her sprawling 900-acre Texas ranch after she accidentally put her Tesla into reverse. 

The shocking details have been revealed only weeks after the death of the 50-year-old was placed under 'criminal investigation'.

Chao was found dead shortly after midnight on February 11 when her car was pulled out of the body of water on her ranch in Johnson City, around 40 miles from Austin. 

She had been spending the weekend with seven of her closest girlfriends who had flown in from New York to celebrate the Chinese New Year while her husband,  venture capitalist Jim Breyer, was away at a conference in Dubai.

The group had been enjoying all that the Hill Country ranch had to offer, complete with a dozen horse stables, a swimming pool, putting green and basketball court.

Angela Chao, a billionaire shipping industry CEO, tragically drowned in a pond at her Texas ranch after accidentally putting her Tesla in reverse 

Chao is said to have made a mistake with the Tesla gearshift and put the car into reverse sending it into a pond

The sprawling 900-acre ranch has a number of ponds set about the property

Angela Chao (far right) is pictured in 2015 with her sister, former Secretary of Transportation Elaine Chao (left), her brother-in-law Mitch McConnell (second from left), now President Joe Biden (center), and her father, James Chao (second from right)

On the day before that fateful night, Chao had been proudly showing off property's flora and fauna with everything from babbling streams and creeks together with wild turkeys and deer. 

After enjoying an evening of food and drink with her friends at a 10-bedroom guesthouse on the ranch, known as 'the inn', Chao decided to return to the main house, where her son was soundly asleep.

The February night air was chilly and rather than walk back to the residence, Chao thought it easiest to drive instead. 

After all, it was only a four minute drive away on terrain she knew well. But the evening took taken a sudden, tragic turn as Chao shifted her metallic dark blue Tesla Model X SUV into 'reverse' rather than 'drive' as she tried to make a three-point turn. 

While performing the maneuver, the electric car plummeted down an embankment and straight into one of estate's many ponds where it quickly began to sink below the waterline.

Unable to open the car door or window to free herself, Chao made a panicked phone call to one of her friends inside the nearby guard house. 

It is a mistake she had made before with the Tesla gearshift, reports the Wall Street Journal.

Chao had been spending the weekend with seven of her closest girlfriends celebrating the Chinese New Year while her husband, venture capitalist Jim Breyer, was away at a conference

Her father, James S.C. Chao, remembered his youngest daughter as 'thoughtful, kind and devoted' as well as being a much-loved 'charismatic and visionary leader'

Angela Chao backed her car into the largest pond in view, which abuts the guest house she and her husband referred to as 'the inn'

On Friday night, Chao's husband, Jim Breyer, simply wrote: 'We are heartbroken.'

There was little any of the friends could do. The pond was in complete darkness and Chao's car was sinking fast into the chilly black water. 

Typically, the driver and passengers of a sinking car would only have only around 60 seconds to get out before the vehicle would become extremely difficult to escape from.

Years ago, drivers would have been able to wind down the window to get out, but nowadays a driver would need to roll the electric windows within seconds of an accident occurring - something that might seem counterintuitive.

Opening a car door would also prove next to impossible given the water pressure against the side of the door.

Chao's friends called the emergency services in the hope they would arrive on the scene and be able to tow her SUV out of the pond and free her from inside the vehicle.

But the rescue was not an easy one. Her friends, the ranch manager, then paramedics, firefighters and sheriff's deputies all tried in vain to break the windows to the car in the hopes of freeing Chao.

The first emergency services were on the scene within 24 minutes of receiving the initial 911 call.

The terrain was not an easy one to cross and some first responders walked to the scene where Chao's friends were beside themselves.

By now, the car was completely submerged with some brave police officers even managing to stand on the vehicle as they desperately tried to rescue Chao by whatever means possible.

The rescue kicked into high gear with lighting set up to aide the response. 

A dive team might have been ideal at this stage, but none were available.

Tools were used in an attempt to break the tempered glass or sturdier laminated glass - but they rescue tools were essentially rendered useless in the water.

When a tow truck arrived on the scene, a cable used to drag the car out would not reach and it took some more time before a longer one could be found.

There was also a fear of electrocution by some members of the dive team given the vehicle involved ran off an electric battery. 

Teams fought for more than an hour before eventually, the car was hauled from the murky waters. 

The doors were opened at which point gallons upon gallons of water gushed out.

Chao was still inside and unresponsive Ben Oakley, emergency services chief of Blanco County told WSJ.com. 

Efforts to resuscitate Chao began immediately with paramedics delivering 'advanced life support' for 43 minutes - but all were in vain. 

The accident is now under criminal investigation. 

In a letter to Texas Attorney General Ken Paxton, the Blanco County Sheriff's Office said: 'This incident was not a typical accident.

'Although the preliminary investigation indicated this was an unfortunate accident, the Sheriff's Office is still investigating this accident as a criminal matter until they have sufficient evidence to rule out criminal activity.'

On Friday night, in response to The Journal's reporting, Chao's husband simply wrote: 'We are heartbroken.'

Angela Chao is pictured with her husband Jim Breyer in 2023

From L to R, the Chao sisters: Grace, Christine, Elaine, May and Angela Chao, pictured in 2016

Chao's father, James S.C. Chao, remembered his youngest daughter as 'thoughtful, kind and devoted' as well as being a much-loved 'charismatic and visionary leader.'

He said in a statement: 'It is with a heavy heart and deep sadness that I announce the passing of my beloved youngest daughter, Angela Chao.

'Angela is a brilliant woman, a charismatic and visionary leader and much-loved by all her sisters, our entire family and friends. 

''As a daughter, sister, mother, aunt, wife and friend, she was unfailingly filial, thoughtful, kind and devoted.'

The family added: 'As a trail blazer for women in the executive suite, she inspired others to pursue their dreams. She also loved music and tried the French horn as her instrument when young, insisting on carrying it herself to every lesson.

'These early experiences created a lifelong, passionate commitment to the fine arts.

'Angela's name in Chinese sounds like the characters for peace and prosperity. She certainly gave more than her share of both to this world. 

Chao was the sister of McConnell's wife, Elaine Chao, who has served as secretary of both the Labor and Transportation departments. McConnell and Chao are seen here in 1993

During his tearful speech last month, McConnell brought up the passing of Angela saying it was tragic 

'Her absence leaves a void not only in our hearts, but in the Asian-American community.'

Chao was the chair and CEO of her family's shipping business, the Foremost Group, and the president of her father's philanthropic organization, the Foremost Foundation. 

Chao was also the sister of Mitch McConnell's wife, Elaine Chao, who has served as secretary of both the Labor and Transportation departments. 

McConnell announced earlier this week that he would be stepping down as the Republican leader in the Senate later this year. 

Speaking on the Senate floor, he said: 'This has been a particularly difficult time for my family. We tragically lost Elaine's younger sister Angela, just a few weeks ago.

'When you lose a loved one, particularly at a young age, there's a certain introspection that accompanies the grieving process.'

Angela Chao was married to Jim Breyer, who has an estimated net worth of $2.9billion. 

Breyer is part owner of the Boston Celtics, and previously served on the boards of Facebook, Walmart, Marvel, News Corp. and Dell. 

The Chao family: Standing far left is Angela - who died in the car crash. In the back row is her sisters Christine, May, and Grace. Sitting next to her father James S.C. Chao is Elaine Chao. James S. C. Chao is seated next to portrait of his late wife

Angela Chao is pictured with her first husband Bruce Wasserstein, who died in 2009 just months after they wed

She was previously married to billionaire banker Bruce Wasserstein - who died in 2009, just months after they wed.

The Chao family is the only one in the history of the school to have had four daughters attend the Harvard Business School. 

Angela completed her bachelor's in economics, graduating with summa cum laude, in just three years.

She then went on to attend Harvard Business School before joining over her father's company, The Foremost Group, in 1996. Chao became the CEO of the company in 2018.

She was remembered for her 'pioneering leadership' and for being a 'formidable executive' in the shipping industry.

In June 2016, Chao was also appointed as independent director of the board of the Bank of China.

Angela Chao was a founding advisory council co-chair of The Asian American Foundation - who gave a statement on the news of her tragic death.

The nonprofit said: 'The Asian American Foundation is heartbroken to learn of the devastating death of Angela Chao, a beloved businesswoman, philanthropist and respected leader.

'Angela has left an indelible mark on The Asian American Foundation and the AAPI community.