Earlier quoted context omitted.
For some context in case anyone is curious: putting together information from various websites suggests that the following is the oldest plane in commercial service today. https://m.planespotters.net/airframe/Boeing/737/5Y-CGV-Zone-... It is a Boeing 737-200 and it has been in service for 43.7 years.
Hardly. There are still DC-3's in commercial operation, and production of those ended in 1942. http://www.buffaloairways.com/ is one operator.
Are there any such planes used for regular scheduled (passenger) airline services? It appears to me that Buffalo Airways is charter and cargo only.