Types of Airplane Contra-Rotating Propeller Drives

This is a short explanation of a few different types of airplane propeller coaxial counter-rotating (contra-rotating) drives

0:00 Introduction
0:35 Simplified Animation
1:09 Types of Contra-Rotating Drives
2:40 Gear Ratios of a Dual Compound with Reversing Idle Gear
4:08 Bevel Gear Configuration
4:16 Planetary Gear Configuration
4:22 Software Used to Model the Gearboxes

More videos:
Original contra rotating animation:    • Contra-Rotating Coaxial Propeller Drive  
Planetary contra rotating animation:    • Contra rotating propellers with a planetar...  

Images and links used in this video:

NASA TM 82983
Technology and Benefits of Aircraft Counter Rotation Propellers
1982 Strack, Knip, Weisbrich, Godston and Bradley
https://ntrs.nasa.gov/api/citations/1...

Avro Shackleton photo
https://commons.wikimedia.org/wiki/Fi...
RAF, Public domain, via Wikimedia Commons

TU-95 Туполев photo
https://commons.wikimedia.org/wiki/Fi...
Photo: RAF/MOD, OGL v1.0OGL v1.0, via Wikimedia Commons

YouTube
An Explanation Of The Rolls Royce Griffon Counter Rotating Propeller Gearbox
FlightEngineering1
   • An Explanation Of The Rolls Royce Griffon ...