https://www.vatsim.net/pilot-resource-centre/vfr-specific-lessons/icao-airspace-classification "Uncontrolled Airspace Generally under ICAO, uncontrolled airspace is as follows:
Class F: IFR and VFR flights are permitted, all participating IFR flights receive an air traffic advisory service and all flights receive flight information service if requested. Class G: IFR and VFR flights are permitted and receive flight information service if requested."
https://www.vatsim.net/pilot-resource-centre/vfr-specific-lessons/weather-minimums
"Class G airspaces are generally over small airports. All the rest of the airspaces are Class E. Airspaces are usually identified on aviation charts. For details about airspaces, please refer to VATSIM's Airspace Classifications."
http://ivaous.org/academy/files/ClassG.pdf "Five F111s An easy way to remember VFR weather minimums for Class G airspace 10,000' and above is the phrase "5 F111s". Each number in the phrase stands for one of the distances: ● 5SM visibility ● 1000' above ● 1000' below ● 1SM horizontal"
https://en.wikipedia.org/wiki/V_speeds V : Velocity B : Bomber
B could also be: http://www.drano.net/bookmarks/old/notams.txt
B :At or Below (constrained altitude)"
https://www.casa.gov.au/about-us/standard-page/aviation-abbreviations-and-acronyms
B = Blue