AHS International (The Vertical Flight Technical Society) https://www.vtol.org/
Aviation Handbooks & Manuals (FAA) https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/
Avjobs: Helicopter Pilot Jobs https://www.avjobs.com/careers/detail.asp?Job_Title=Pilot&Category=In%20Flight&Related=Helicopter%20Pilot&RecID=105
CH-47 Chinook Helicopter https://www.boeing.com/defense/ch-47-chinook/
CHC Helicopter Association https://www.chc.ca/
Helicopter Association International - https://www.rotor.org/
Helicopter Flying Handbook - https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/helicopter_flying_handbook/
Helicopter Foundation International https://www.helicopterfoundation.org/
Helicopter Route Charts (FAA) https://www.faa.gov/air_traffic/flight_info/aeronav/productcatalog/vfrcharts/helicopter/
How Helicopters Work https://science.howstuffworks.com/transport/flight/modern/helicopter.htm
International Radio Controlled Helicopter Association https://www.ircha.org/
National Oceanic & Atmospheric Association https://www.noaa.gov/
Rotorcraft (FAA) https://www.faa.gov/aircraft/air_cert/design_approvals/rotorcraft/
Sikorsky https://www.sikorsky.com/Pages/Home.aspx
Vietnam Helicopter Pilots Association https://www.vhpa.org/
Whirly-Girls International Women Helicopter Pilots https://www.whirlygirls.org/