In Trapped in the Sky
Pod 2 is one of Thunderbird 2's pod transporters. It primarily carries the Electromagnetic Pod Grabs, which were used during the events of End of the Road and Brink of Disaster.
Chip Morrison is seen sleeping inside Pod 2 on his way home to England in Security Hazard.
Pod 2 is used when Thunderbird 2 visits the Himalayas in The Abominable Snowman, although its contents are not used in the rescue mission.
The pod is destroyed in City of Doom after it's dropped by Thunderbird 3. Thunderbird 2, already present at the scene of the rescue, doesn't have enough time to go back to Tracy Island to pick up the pod and return, and so TB3 must attempt to deliver the Pod to the rescue zone itself. However, the delivery does not go to plan, and Pod 2 plummets towards Earth - destroying the pod and everything inside.
(City of Doom)