Fixed-Wing aircraft

• Aircraft Engine Information Articles relating to aircraft engines, including vibration information.
• Airflow Systems Manufacturer of aircraft air conditioning and turbo intercooler products.
• Cessna Pilots Association A unique technical information service for Cessna owners.
• Cessna Aircraft Company The Cessna Aircraft company
• Hartzell Propeller Inc. Hartzell Propeller Incorporated
• McCauley Propeller Systems McCauley Propeller Systems
• Mooney Aircraft Company The Mooney Aircraft company
• New Piper Aircraft Company The New Piper Aircraft company
• Raytheon (Beech) Aircraft Raytheon Aircraft
• Sacramento Sky Ranch Information for fixed-wing aircraft owners, including aircraft engine vibration information.
• Sensenich Propeller Company Sensenich Propeller Company

Rotary-wing aircraft

• American Helicopter Society  The Vertical Flight Society.
• Helicopter Association International The international association dedicated to helicopters.
• Helicopter History Site Site dedicated to helicopter history.

Homebuilt aircraft (all types)

• CH-7 Home Page HeliSport Helicopter home page.
• Experimental Aircraft Association The leader in Recreational Aviation.
• Homebuilt.org Lots of information for the homebuilder.
• Mid-American Helicopter Homebuilt helicopters.
• Mike Hartman's Homebuilt Page Many links to sites concerning homebuilt aircraft.
• Popular Rotorcraft Association The association for rotorcraft homebuilders
• Rotorway.org An Independent Source for Rotorway Helicopter Information.
• Sport Helicopter & Pilot Global Exchange Articles and reference information relating to homebuilt helicopters.

• Aircraft Maintenance Technology The magazine for Aircraft Maintenance.
• Light Plane Maintenance Maintenance information for the aircraft owner.
• Pama.org Professional Aviation Maintenance Association homepage.
• The Aircraft Mechanic's Home Page Connect with other aircraft mechanics.

General Vibration

• Vibration Institute A nationally recognized not-for-profit organization dedicated to the exchange of practical information about vibration and condition monitoring.