A man charged in the 2019 friendly fire death of a veteran NYPD detective pleaded guilty Wednesday to aggravated manslaughter and robbery. He faces 33 years in prison.

Christopher Ransom, who had initially been charged with murdering 42-year-old Det. Brian Simonsen, waived his right to appeal during the hearing and answered affirmatively to questions asked by Judge Kenneth Holdre in court.

He will be sentenced in mid-November.

Queens District Attorney Melinda Katz said Ransom, 30, "set in motion a terrible chain of events that began with a robbery and ended in a spray of bullets."

Simonsen was shot in the chest in February 2019 as he and six other officers opened fire on Ransom during a robbery at a T-Mobile store in Queens' Richmond Hill neighborhood. Another sergeant was wounded.

Ransom, who police say was pointing a fake handgun, had said the shooting stemmed from a "prank gone horribly wrong." He said he returned the workers' money -- a claim that investigators deny -- but police were already responding.

NYPD officers discharged a total of 42 rounds at the scene within 11 seconds, investigators have said. 

A criminal complaint released after the shooting said Ransom and another man netted $1,000 and 25 iPhones from the robbery. They planned to split the proceeds.

In an interview after his arrest, Ransom said he was "not a monster" and didn't anticipate what happened. Police described him as a career criminal with more than two dozen arrests prior to this case; friends called him an eccentric prankster.

Ransom, who has 25 prior arrests including one for impersonating a police officer, was also struck several times by bullets, but recovered. An attorney representing Ransom had no comment on Wednesday. Ransom will not appeal the sentencing.

A 19-year veteran of the NYPD, Simonsen was known since childhood as "Smiles" for his bright, welcoming nature, colleagues and friends said.

He grew up on the east end of Long Island. He and his wife continued to live close by in Calverton -- more than an hour's drive from the 102nd precinct where he spent his entire NYPD career. Simonsen was survived by his wife and his mother.

"This is a difficult day for his wife, a difficult day for his family," said Detectives Endowment Association President Paul DiGiacomo. "Christopher Ransom, I hope he spends every day of that 33 years behind bars and thinks about how many people's lives he's affected."

And he was beloved by the entire department, too.

"There wasn't a person in the 102 that didn't know him, from the cleaner to the command officer," then-NYPD Chief of Department Terence Monahan said at the time of Simonsen's death. "He was who you called if you had a problem. Wasn't just the cops who knew him well, the community, everyone knew him, that he's the cop you reached out to if a problem needed to be handled."