Why Rotor, not Propellor?
Thread Starter
Joined: Mar 2005
Aviation Qualifications: Military
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From: Aus
Why Rotor, not Propellor?
A propeller is defined as "a device having a revolving hub with radiating blades, for propelling an airplane, ship, etc.", whereas a rotor can refer to many, many disparate things, contained within electric motors to gyros.
How did the helicopter come to have the word "rotor" applied, rather than "propeller"?
The earliest reference to "helicopter rotor" in the aviation press I could find was this article dated 1915.
https://www.flightglobal.com/pdfarch...0-%200266.html
Esoteric I know, and only anorak wearers would be interested.
How did the helicopter come to have the word "rotor" applied, rather than "propeller"?
The earliest reference to "helicopter rotor" in the aviation press I could find was this article dated 1915.
https://www.flightglobal.com/pdfarch...0-%200266.html
Esoteric I know, and only anorak wearers would be interested.
Joined: Nov 2000
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From: White Waltham, Prestwick & Calgary
Probably the distinction might be that rotor blades are flexible, as opposed to propeller blades which are (mostly) stiff and better fit the description of a gyro that id so often used.
Phil
Phil
Joined: Feb 2017
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From: NT
The "auto gyro" was the first flying fling wing, and that was 100+ yrs ago.( january 9th, 1923 )
Many earlier attempts were bogged down trying to understand the dynamics etc, then "teetering" was discovered. The rest is history.
From gyro's bigger things grew.......helicopters were the next step.
Many earlier attempts were bogged down trying to understand the dynamics etc, then "teetering" was discovered. The rest is history.
From gyro's bigger things grew.......helicopters were the next step.
Thread Starter
Joined: Mar 2005
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From: Aus
technically, "rotor" is a set of rotating wings
A helicopter is a "rotary wing" aircraft
Joined: Dec 2008
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From: Top of the World
Propeller is fixed or variable pitch blade bolted onto a Stiff-Wing 
......a Rotor on a Rotor-Craft is lump of metal/plastic thingamabob that can cyclically tilt the disc in a desired direction with the Cyclic Shtick & also have the pitch angle of attack collectively changed by the Collective lever/club (apparently) 
......a Rotor on a Rotor-Craft is lump of metal/plastic thingamabob that can cyclically tilt the disc in a desired direction with the Cyclic Shtick & also have the pitch angle of attack collectively changed by the Collective lever/club (apparently)
Last edited by Vertical Freedom; 12th February 2017 at 07:07.
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From: Lincolnshire
Joined: Oct 2006
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From: USA
For what it's worth...
I seem to recall the following:
Back when "aeroplanes" were being developed, those of the nautical majority had extreme power. Hence the use of a number of nautical terms in aviation: ballast, engine deck, waterline, propeller, and el piloto. After all, these insignificant aircraft were to support naval dominance.
Fast forward and by the time Igor was making headway developers were free to use other terms based on function rather than nautical legacy.
On the flip side, I've read somewhere that a "propeller" provides thrust parallel to the fixed longitudinal axis of a vessel/aircraft and any other thrust provider is not a "propeller."
Lastly, I think this version came from a helicopter design white paper that a "aerodynamic rotor" was an assembly of field removable components and a propeller was a single component.
It is what it is. I'm just glad they didn't go with the word "fan" like some engine people did with the turbojet vs. turbofan.
W1
I seem to recall the following:
Back when "aeroplanes" were being developed, those of the nautical majority had extreme power. Hence the use of a number of nautical terms in aviation: ballast, engine deck, waterline, propeller, and el piloto. After all, these insignificant aircraft were to support naval dominance.
Fast forward and by the time Igor was making headway developers were free to use other terms based on function rather than nautical legacy.
On the flip side, I've read somewhere that a "propeller" provides thrust parallel to the fixed longitudinal axis of a vessel/aircraft and any other thrust provider is not a "propeller."
Lastly, I think this version came from a helicopter design white paper that a "aerodynamic rotor" was an assembly of field removable components and a propeller was a single component.
It is what it is. I'm just glad they didn't go with the word "fan" like some engine people did with the turbojet vs. turbofan.
W1
Joined: Oct 2007
Posts: 300
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From: Texas
Flight Controls Perspective
Working as an engineer in both flight controls and propulsion I have used this discriminator:
If it's primary purpose is solely for propulsion and it dose not have a means for high frequency blade pitch control it is a propeller.
If it's primary purpose is either solely flight control or equally flight control and propulsion, plus it is equipped with a means for high frequency blade pitch control it is a rotor.
Note that on small quad copters that use variable rpm they are called propellers. But on quad copters with collective pitch control they are called rotors.
CTR
If it's primary purpose is solely for propulsion and it dose not have a means for high frequency blade pitch control it is a propeller.
If it's primary purpose is either solely flight control or equally flight control and propulsion, plus it is equipped with a means for high frequency blade pitch control it is a rotor.
Note that on small quad copters that use variable rpm they are called propellers. But on quad copters with collective pitch control they are called rotors.
CTR
