Ryan Chappelle before Day 1

Ryan Chappelle played a large role in several Counter Terrorist Unit operations prior to Day 1.

Stories
Chappelle was largely responsible for coordinating the response to the hostage crisis at the Hotel Long Beach, although it is unclear why he was at CTU Los Angeles or what position he held.

Operation Hell Gate
Ryan Chappelle was the Administrative Director at CTU Los Angeles during the Hell Gate mission. He coordinated operations between Los Angeles and New York with plenty of help from Nina Myers.

Veto Power
Chappelle arrived to ask what Jack Bauer was doing after he raided the Greater Nation compound. Kelly Sharpton, the then Special Agent in Charge was unsure, but Jack informed them he had discovered a lead to a terrorist base. Chappelle grudgingly went along with the plan. Jessi Bandison approached him and told him Sharpton had asked to hack into the Department of Justice's files, specifically that of James Quincy, the Attorney General. Chappelle arrested Sharpton for this. He interrogated Sharpton, and just before he was about to be taken away by the FBI, Chappelle received a call from the Attorney General telling him Sharpton should be released (as he was being coerced by Sharpton's friend Senator Debrah Drexler).

Chappelle also sat in on the briefing with all the department heads when Jack learned about the upcoming assassination attempt on President Barnes. However, Chappelle rebuked Jack when one member realized the threat, supposedly taking place in Los Angeles, was incorrect, as the President would not be in Los Angeles on the supposed day of the assassination attempt.

Trojan Horse
Chappelle was present during the events of Trojan Horse.

Cat's Claw
During the Cat's Claw mission, Chappelle made his way to the conference hall where President Harry Barnes and Chinese premier Xu Boxiong were having a private, unscheduled meeting after the G8 talks of the day which caused much uproar amongst the public. He informed the President an antivirus had been found once Jack Bauer retrieved the vial, and helped the President to get the antidote.

Vanishing Point
Chappelle was present during the events of Vanishing Point.

Chaos Theory
Chappelle was present during the events of Chaos Theory.

Trinity
Chappelle was the Division director of CTU Los Angeles during Trinity. He greeted Jack Bauer, but not until he had seen Jack's identification. He then proceeded to tell off some relaxing workers at CTU, and insisted if Jack did not join CTU, he would not be able to follow up on the mission as he desired.

He later berated Jack for interrogation of some suspects, and second-guessed the CIA operatives actions all day. He was later involved with a conference call with Langley to determine whether it was worth keeping the newly established CTU open, which he eventually convinced them it was thanks to Jack.

Head Shot
Chappelle told Jack to go to Colorado to investigate a threat to the Sky Mount Round Table conference, as well as the disappearance of two dozen members of a cult operating nearby and to see if they were connected. Chappelle thought it was necessary Jack went rather than just giving the case to CTU Denver as he wanted to extend the reach of his influence, as well as having a long-standing rivalry with the head of CTU Denver, Orlando Garcia.