Talk:Quadcopter/Archives/2017

Quadcopters and lift

Quadcopters (in general) do not generate lift - thrust only.

from wiki: lift - "A fluid flowing past the surface of a body exerts a force on it. Lift is the component of this force that is perpendicular to the oncoming flow direction.[1]"

thrust - "Thrust is a reaction force described quantitatively by Isaac Newton's second and third laws. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction on that system.[1]"

The introduction is really start class level (see multirotor, the whole multirotor section should be deprecated to stub or dropped alltogether) - either way the two articles clash and need to be rewritten. — Preceding unsigned comment added by Regijean (talk • contribs) 00:06, 25 April 2017 (UTC)

A suggestion: "A quadcopter, also called a quadrotor helicopter or quadrotor,[1] is a multirotor helicopter that is lifted and propelled by four rotors. Quadcopters are classified as rotorcraft, as opposed to fixed-wing aircraft, because their lift is generated by a set of rotors (vertically oriented propellers)."

Should be: "A quadrotor aircraft, also called a quadcopter or quadrotor, is a multirotor aircraft that achieves flight by use of four rotors. Quadcopters are classified as rotorcraft." — Preceding unsigned comment added by Regijean (talk • contribs) 00:37, 25 April 2017 (UTC)

Thanks for bringing this up. Rotors produce lift. They are rotating airfoils that act in just the same way as fixed airfoils, the air passing them produces lift in the same way and that supports the aircraft. Some of the lift is angles and produces thrust that allows forward flight. Lift opposes weight, whereas thrust opposes drag. See Helicopter rotor, which says: "A helicopter main rotor or rotor system is the combination of several rotary wings (rotor blades) and a control system that generates the aerodynamic lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic drag in forward flight."- Ahunt (talk) 02:33, 25 April 2017 (UTC)

That is not correct. You are conflating propellers and rotor blades, and thus - conflating helicopters and quads.. which are different.

The fact that thrust allows a drone or quad to fly does not make it an airplane; helicopters are airplanes because the blades of the rotating disc generate lift - a difference in pressure (Bernoulli), airplanes may also have props which generate thrust; pitch in the rotor blades allow a helicopter to move along the longitudinal axis from thrust. — Preceding unsigned comment added by Regijean (talk • contribs) 03:28, 25 April 2017 (UTC)

Quadracopters are a form of helicopter; they work the same way. Rotors and propellors are the same thing, they both create a force by rotating airfoils in the air. If the force is upwards we call it "lift" because it opposes gravity. If the force is forward we call it "thrust" because it opposes drag. On helicopters of all stripes when the rotor is tilted forward slightly it produces a thrust vector to oppose drag. The same is true of propellers, when a fixed wing aircraft is nose-up the propeller produces a small amount of lift to oppose weight. In the case of some high-powered aerobatic aircraft they can "hang on the prop" and then the propeller is producing all lift, opposing weight. - Ahunt (talk) 15:38, 25 April 2017 (UTC)

"Quadracopters are a form of helicopter" No. Quadcopters are a form of multirotor aircraft. This is an issue, the two wiki articles need to be synced.

"Rotors and propellers are the same thing" No. I addressed this above.

"they both create a force by rotating airfoils in the air." No.

"If the force is upwards we call it "lift" because it opposes gravity." No.

"If the force is forward we call it "thrust" because it opposes drag." No.

"On helicopters of all stripes when the rotor is tilted forward slightly it produces a thrust vector to oppose drag." No. The rotor does not "tip forward" the rotating blades create a disc, it's dynamics are described as rotor disc tip path plane.

"The same is true of propellers, when a fixed wing aircraft is nose-up the propeller produces a small amount of lift to oppose weight." No. Airflow over wings generate lift. Specifically the difference in pressure due to wing design.Regijean (talk) 17:38, 25 April 2017 (UTC)

There really isn't much point in discussing this any further if you are just going to deny the fundamentals of aerodynamics and aviation terminology as well. I am a helicopter test pilot, I actually do understand the subject here. Regardless, there is no consensus for the changes you have proposed, unless some other editors weigh in here. - Ahunt (talk) 17:56, 25 April 2017 (UTC)

As part of a flight test team, I've regularly flown with pilots being recertified; I am relieved that my conversations have been only with the instructors.

FAA Pilot's Handbook of Aeronautical Knowledge-

• "Thrust—the forward force produced by the powerplant/ propeller or rotor. It opposes or overcomes the force of drag. As a general rule, it acts parallel to the longitudinal axis. However, this is not always the case, as explained later."

• "Drag—a rearward, retarding force caused by disruption of airflow by the wing, rotor, fuselage, and other protruding objects. As a general rule, drag opposes thrust and acts rearward parallel to the relative wind."

• "Lift—is a force that is produced by the dynamic effect of the air acting on the airfoil, and acts perpendicular to the flight path through the center of lift (CL) and perpendicular to the lateral axis. In level flight, lift opposes the downward force of weight."

Your postings are not in agreement with the above.

Please see "FAA ROTORCRAFT FLYING HANDBOOK" for helicopter flight dynamics, esp. tip path plane. Regijean (talk) 19:12, 25 April 2017 (UTC)

Actually the FAA entirely agrees with what I said. The FAA quote above completely refutes each point you made above. Regardless, though, as I said there is no support for your proposed changes. - Ahunt (talk) 19:44, 25 April 2017 (UTC)

Where in wikipedia.org/wiki/Helicopter or in wikipedia.org/wiki/Helicopter_rotor does the word 'propeller' appear? — Preceding unsigned comment added by Regijean (talk • contribs) 03:59, 26 April 2017 (UTC)

Request for comments RFC rotorcraft flight dynamics

There is no consensus to make the proposed changes. Cunard (talk) 01:12, 4 June 2017 (UTC)

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

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Should the "Introduction" section be clarified to disambiguate props and rotors? Regijean (talk) 22:02, 25 April 2017 (UTC)

Should the rotorcraft classification hierarchy be clarified?Regijean (talk) 22:03, 25 April 2017 (UTC)

What reliable sources can you cite that specifically state that these types of quadrotors are not helicopters, and that they use propellers, not rotors? This last claim is a really odd. They are called "quadrotors", not "quadpropellers", and "rotorcraft", not "propellercraft". - BilCat (talk) 23:09, 25 April 2017 (UTC)

I must begin by citing slippery slope. Failure to understand and accept that propellers and rotors are different is a fundamental misunderstanding of aircraft flight principle. It is a slippery slope because many aircraft fall into the Rotorcraft classification. And I did state that the nomenclatures needs clarification.

The article title is Quadcopter, not quadrotor.

Throughout the The Rotor Craft Flying Handbook flight dynamics of rotorcraft are established. One such aircraft is the gyroplane, and the FAA handbook clearly details differences in propeller and rotor functions. some examples -

"In a conventional airplane, the engine and propeller are permanently connected. However, in a helicopter there is a different relationship between the engine and the rotor. Because of the greater weight of a rotor in relation to the power of the engine, as compared to the weight of a propeller and the power in an airplane, the rotor must be disconnected from the engine when you engage the starter. A clutch allows the engine to be started and then gradually pick up the load of the rotor."

"THRUST

Thrust in a gyroplane is defined as the component of total propeller force parallel to the relative wind. As with any force applied to an aircraft, thrust acts around the center of gravity. Based upon where the thrust is applied in relation to the aircraft center of gravity, a relatively small component may be perpendicular to the relative wind and can be considered to be additive to lift or weight."

"ROTOR FORCE

As with any heavier than air aircraft, the four forces acting on the gyroplane in flight are lift, weight, thrust and drag. The gyroplane derives lift from the rotor and thrust directly from the engine through a propeller."

"ROTOR LIFT

Rotor lift can most easily be visualized as the lift required to support the weight of the aircraft. When an airfoil produces lift, induced drag is produced. The most efficient angle of attack for a given airfoil produces the most lift for the least drag. However, the airfoil of a rotor blade does not operate at this efficient angle throughout the many changes that occur in each revolution. Also, the rotor system must remain in the autorotative (low) pitch range to continue turning in order to generate lift."

Regijean (talk) 00:00, 26 April 2017 (UTC)

"Helicopter means a rotorcraft that, for its horizontal motion, depends principally on its engine-driven rotors." - FAA FAR 1.1 Definitions, "helicopter means a power-driven heavier-than-air aircraft that derives its lift in flight from aerodynamic reactions on one or more power-driven rotors on substantially vertical axes; (hélicoptère)" Transport Canada CAR 101.01 Interpretation A quadcopter is a type of helicopter.

Rotor requires a blade that is designed to produce lift; quadcopters use props, a prop blade provides thrust - eg. it flies on thrust, not lift.Regijean (talk) 00:50, 26 April 2017 (UTC)

I have provided refs that show that quadcopters are helicopters and that they use rotors. To refute this you need to cite a ref that says that both the CARs and FARs are wrong. - Ahunt (talk) 01:54, 26 April 2017 (UTC)

No, you have not, you only misinterpret. My citation is the FAA.Regijean (talk) 02:54, 26 April 2017 (UTC)

"Main rotor means the rotor that supplies the principal lift to a rotorcraft." - FAA FAR 1.1 Definitions. The device that provides lift on a rotorcraft is called a rotor. - Ahunt (talk) 00:21, 26 April 2017 (UTC)

"Lift" is the key word, throwing a ball into the air is not an example of lift. Lift is specifically the difference in pressure of the airflow at the top of the wing shaped surface as compared to the bottom of the wing shaped surface. Regijean (talk) 00:50, 26 April 2017 (UTC)

The ref, FAR 1.1 says that quadcopters are helicopters, helicopters have rotors and rotors provide lift. To refute this you need to cite a more authoritative reference. - Ahunt (talk) 01:54, 26 April 2017 (UTC)

No it does not. My citation is the FAA.Regijean (talk) 02:54, 26 April 2017 (UTC)

(edit conflict) So a "quadcopter" isn't a type of "helicopter"? That's even worse. Also, your reiteration of the screed you already posted above, as if I'm too stupid to have not seen it, doesn't address my request for reliable sources that specifically state that these types of quadcopters are not helicopters, and that they use propellers, not rotors. If it had addressed my request, I wouldn't have asked. I don't see a need to comment any further. - BilCat (talk) 00:30, 26 April 2017 (UTC)

"In a conventional airplane, the engine and propeller are permanently connected. However, in a helicopter there is a different relationship between the engine and the rotor" Quadrotor props are directly connected to the motor.Regijean (talk) 00:50, 26 April 2017 (UTC)

That is totally spurious. Some propeller driven aircraft have clutches that allow the prop to freewheel and stop when the engine is at idle, as decribed here. Also some helicopters are directly driven, like this one. - Ahunt (talk) 01:54, 26 April 2017 (UTC)

The FAA is spurious?

That RC is a a helicopter because it has rotor blades, not props.172.58.91.116 (talk) 02:35, 26 April 2017 (UTC)

The ref you have quoted is FAA educational and advisory material. The ref I have quoted is regulatory material. The Rotorcraft Handbook has been replaced by a newer publication the Helicopter Flying Handbook the preface to which says that 14 CFR (the FARs) take precedence. So you can't quote FAA advisory material as over-ruling regulatory material. As I showed above, the advisory material only gives general information and doesn't account for all cases, as I illustrated.

Anyway, it is pretty clear that there is no support for your proposed text changes, either from the FARs or from editors here. Unless some more editors choose to chime in, I think we can close this discussion as "no consensus" and getting close to WP:DEADHORSE. - Ahunt (talk) 11:14, 26 April 2017 (UTC)

Here is a list of FAA aircraft types that can be certificated

Balloon

Glider

Large Airplane

Rotorcraft

Small Airplane

Small/Large Airplane

Unmanned Aircraft System

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/MainFrame?OpenFrameSet

quadcopters must be controlled by computer and thus is an UAS.

QED. Regijean (talk) 03:45, 27 April 2017 (UTC)

You comments there are all totally off topic. I think we can close this discussion now as no consensus to include your proposed text. - Ahunt (talk) 13:28, 27 April 2017 (UTC)

Comments on RFC

• Comment The foregoing discussion is at cross purposes because of factors that I hope will be borne in mind before resumption, and appropriate amendments of the article are not the ones debated in this RFC.
  • The discussion was futile because the semantics were determinedly in conflict
  • The range of concepts considered in the conflict was too narrow; eg the fact that a rotor might be used for lift does not mean that it cannot be used for horizontal propulsion as well.
  • Too little attention was paid to existing related articles, such as Rotorcraft and Helicopter rotor
  • Too little to existing text and its linkage to the other articles.

Though the items concerning the distinctions are not without relevance and notability, most of them are not directly appropriate to this article; eg, what matters here is that the quadcopters have four rotors, not what rotors are. I think we could consider merging this article with Multirotor or even Unmanned aerial vehicle, but I grant that there may be adequate reason for retaining quadcopters as an adequately distinct topic; however, to justify this there should be more careful attention to linkage.
For example, in this article it is undesirable to explain: "...rotors (vertically oriented propellers)..." That is not our job here. Either the reader knows what a rotor is and how it differs from a propeller, or doesn't know or care, or doesn't know and does care, in which case the right place to explain the concept is in the appropriate article, without introduction of distracting and debatable points. That remark should have read: "...rotors rather than propellers...", leaving the reader to decide for himself whether he wants to know, and presenting the means to find out at the price of a click or two. JonRichfield (talk) 10:45, 20 May 2017 (UTC)

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The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Use of drone term

It is not necessary to keep adding that these are drones in the lead para. Most earlier quadcopters were manned aircraft and their use as unmanned aircraft is fully explained in the fourth para in the lead section. Putting in "unmanned quadcopters are also called drones, however this is a more general term that applies also to other non-quadrotor vehicles." is like putting in "Cars are also called vehicles, however this is a more general term that applies also to other non-car vehicles." It adds nothing to the article of any value. - Ahunt (talk) 13:22, 3 November 2014 (UTC)

Sorry, but there is much difference. Term vehicle is widely historically used, term drone is newly used just for quadcopters which is unmanned. My point was, that nowadays in many shops you are not going to buy "quadcopters" or "unmanned aerial vehicles", but just "drones". This term is nowadays widely used. Also, it is even a few times used in this article. Jirka.h23 (talk) 14:07, 3 November 2014 (UTC)

It is already explained in the lead for the article, it doesn't need restating in the very first para, especially when the vast length of the history of quadcopters has been as manned aircraft. - Ahunt (talk) 20:10, 3 November 2014 (UTC)

Drone is the most used word for them, the term used in mainstream media articles about them, and this article is one of the options on the drone disambig page. Using this word in the first paragraph of the article immediately makes it clear in clear but precise non-specialist language what type of machine this article is about.--85.148.123.77 (talk) 23:23, 15 January 2017 (UTC)

Please read the article, historically these have most usually been manned aircraft, they are not just drones. - Ahunt (talk) 03:20, 16 January 2017 (UTC)

What do you mean with 'most' exactly? there are about 5 manned models listed, all of them failed experiments and there are hunderds of unmanned models already with much much higher production numbers per model. The word 'historically' includes everything up until now you know. But okay I will rephrase it a bit. --85.148.123.77 (talk) 10:41, 17 January 2017 (UTC)

You can't say a quadcopter is a type of drone when there are obviously manned aircraft that use this configuration. They are not all historic cases as well. There are new human-carrying ones on the way, too, like the Ehang 184. - Ahunt (talk) 15:37, 17 January 2017 (UTC)

Well that's not what I said in the last edit, I said they usually are. Anyway, most quadcopters in use are drones. Drone is the common term for these quadcopters used overwhelmingly in the media and everyday language. The drone disambiguation page links here. We have to mention the term in the opening paragraph so people understand this is the page with information about drones that they are looking for and also so that people that don't know anything about it yet, know that the most common term for these is drone. So how would you put it in if you don't like my suggestion?--85.148.123.77 (talk) 19:32, 17 January 2017 (UTC)

And for your information, cars are mentioned in the opening paragraph of the Vehicle article and in the opening paragraph of the car article it is mentioned that it's a type of vehicle :) --85.148.123.77 (talk) 19:35, 17 January 2017 (UTC)

It is already clearly explained in the lead section. Almost half the lead section is about the use of the configuration for drones. - Ahunt (talk) 21:28, 17 January 2017 (UTC)

Concur with Ahunt. Not all drones are quadcopters, and not all quadcopters are drones. Unless you have a reliable published source that specifically equate the two words as interchangeable, please WP:DROP THE STICK. - BilCat (talk) 00:09, 18 January 2017 (UTC)

• Strong support for keeping the drone term and with what 85.148.123.77 and User:Jirka.h23 have said here. Especially with Drone is the common term for these quadcopters used overwhelmingly in the media and everyday language. The term really needs to be incorporated into the article. I also ask users to please stop citing this "please drop the stick" essay to end debates that they would like to end quickly - this is not constructive for healthy and due proper discussions. Note that "incorporating" doesn't mean that potential differences in scope of the two terms shouldn't be explained in the article if they do exist. --Fixuture (talk) 10:29, 4 July 2017 (UTC)

Please cite reliable published sources that back up the claim that "Drone is the common term for these quadcopters used overwhelmingly in the media and everyday language". Unless you can do that, we have nothing new to discuss here. - BilCat (talk) 11:59, 4 July 2017 (UTC)

The term is already incorporated right in the lede section of the article. Please read it and see if that doesn't address the use of this aircraft configuration in small drones. - Ahunt (talk) 12:29, 4 July 2017 (UTC)

@BilCat: There are many more sources but here are some which either use the term "quadcopter drone" or both interchangeably (in conceptual reference to a quadcopter drone):
[1], [2], [3], [4], [5], [6], [7], [8], [9], [10]

Furthermore in this Google Trends statistic the two terms seem to be highly related and the drone term appears to be more popular.

Also according to many other sites "quadcopters" are a type of drones.

To conclude: drone and quadcopter are often used interchangably if a "quadcopter drone" is meant (which is the case for an increasing number of citizens) and the lead should definitely a) display it as an alternative term for it b) make it clear that quadcopters are one type of drones / drone-design.

@Ahunt: As of right now the lead only says Quadcopter designs also became popular in unmanned aerial vehicle (UAV or drone) research. Imo that is not enough and somewhat misleading or at least worryingly unclear; to make it clear: quadcopter designs have become popular drone designs. This part needs to be rewritten.

--Fixuture (talk) 18:46, 4 July 2017 (UTC)

"...make it clear that quadcopters are one type of drones / drone-design." Not all drones are quadcopters, and not all quadcopters are drones. - BilCat (talk) 21:32, 4 July 2017 (UTC)

I agree the lede could be clearer on that, so I have fixed it. - Ahunt (talk) 00:11, 5 July 2017 (UTC)

I also agree with User:BilCat on this. Any ref that says that drones are quadcopters and quadcopters are drones is just in error and is therefore demonstrably not a reliable source. The article contains many examples, historical and modern, of manned quadcopters and there are also many, many drones, again modern and historical, that are not configured as quadcopters. While there are some drones that are quadcopters, not all are and therefore drone =/= quadcopter and quadcopter =/= drone. - Ahunt (talk) 00:11, 5 July 2017 (UTC)