Abstract: Methods and systems for providing platform agnostic flight management data access for a flight management system (FMS) of an aircraft have been developed. First, a configuration file is loaded to a configuration database. The configuration file is for a data format of an external data source from the aircraft. Upon receiving a data access request from a user for external data from the external data source, downloading the configuration file is downloaded to an FMS data formatter. The configuration file is parsed with a data processor component of the FMS data formatter to update a rule set. The FMS data formatter receives an external data file from an application programing interface (API) of the external data source. The external data file is parsed with a rule engine of the FMS data formatter using the updated rule set. A flight plan file is generated with the FMS data formatter using the parsed external data file and sent to the FMS on the aircraft.