The U.S. aircraft register, updated daily
Who holds what · as the FAA records the name

Provincetown-Boston Airlines

Named as the FAA publishes it on its approvals.

Holds 2 approved modifications, most of them for the Douglas DC-3. FAA spelling: Provincetown-Boston Airlines.

Approved modifications 2 · newest first

Douglas DC-3 1
1985-01-23SA1739SO · Installation of shoulder harness provisions for pilot, co-pilot and observer. · DC3A-S1C3G, DC3A-S1CG, DC3A-S4C4G
1984-11-09SA1698SO · Installation of restraint bar for underseat baggage stowage. · YS-11A-600, YS-11A-500

Source: FAA Dynamic Regulatory System (type certificate data sheets, supplemental type certificates, parts manufacturer approvals, technical standard order authorisations). An organisation's name is as the FAA spelled it on each record; related spellings are separate pages.