NASA TECHNICAL NOTE TN D-3380 “Use of aircraft for ZERO-GRAVITY environment” analyzes different aircraft in zero gravity flight profile. The Lockheed F-104 is listed as the best No Gravity Platform Environment, compared to any other flying platform having the capability of a profile with a theoretical weightless duration of 90 seconds.
Starfighters Aerospace has the capability of making the modifications in order to operate the aircraft in its entire theoretical Zero Gravity Duration Profile.
Readiness status of this type of modification would provide 90 seconds of Zero Gravity Flight, by far the most extensive Weightless Duration Platform Worldwide. The average weightless flight time available by current providers is 25 seconds.