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Motor and engine aren’t interchangeable. Or are they?

By Ben Sclair · August 19, 2018 ·

Words matter. And as language evolves, words sometimes take on new or additional meanings. And that time spent in transition can be difficult to navigate.

I received an email from a reader who took a bit of exception with my use of the term “electric engine” in a recent column. For context, I said, “Electric engines will become reality. Battery capacity will improve to the point of being practical.”

Disclaimer: I’m not mechanical. At all.

Amazon’s Prime Air

From the email I received: “I know we call engines motors, but the reverse isn’t appropriate. Motors convert energy to power; engines convert fuel to power by burning it.”

To the letter writer, the use of engine next to electric is akin to “fingernails on a chalkboard.”

According to Merriam-Webster:

  • Engine is defined as a machine for converting any of various forms of energy into mechanical force and motion.
  • Motor is defined as any of various power units that develop energy or impart motion such as a small compact engine, a gasoline engine, or a rotating machine that transforms electrical energy into mechanical energy.

When I look at those definitions, I read them as nearly similar. To this non-mechanical guy, engines and motors are magical things that covert energy (fuel or stored electricity) into — in the case of airplanes — propulsion.

Interestingly, Brian Smith said, “First off an aircraft engine is not referenced as a motor. It’s an engine. That’s all. Good day,” on a recent story about new features on the Terrafugia flying car.

Pop or soda? I rarely drink either, but many people feel strongly one way or the other. In either case, I typically understand what a person is referring to. And so did the author of the email. But words do matter.

So, what do you think?

I try not to use big words. Actually, I don’t really have to try because I don’t know that many big words. But I do try to use the words I do know properly. Some days are better than others.

This feedback reminded me of our discussions regarding what to call “drones.” I prefer RPA (remotely piloted aircraft), but drone is much easier to say and for someone to understand. After all, it is one of those words that has taken on additional meanings and entered the broader conversation.

License or Certificate?

Referring to that piece of plastic in your wallet that states you are a pilot: Do you think of that as a license or a certificate?

While it doesn’t rise to “fingernails on a chalkboard” when I hear it, I do pause each time I read or hear “Private Pilots License.”

The difference? Both are earned following a successful exam, but a license expires after a stated period of time while a certificate is valid until surrendered or taken.

I took an 11-year hiatus from flying in the early 2000s. But I was still a certificated pilot. And I’m mostly current today.

If I let my driver’s license expire I can no longer call myself a licensed driver.

While words do matter, I don’t feel they should matter too much.

Via Rotten Tomatoes

Back in the 1990s my wife and I went to Seattle to hear educator Joe Clark speak. Mr. Clark was the subject of the movie “Lean on Me” starring Morgan Freeman as the principal committed to cleaning up a tough inner city high school in New Jersey.

Sadly, Deb and I left disappointed. Mr. Clark spoke at a level much higher than either of us could comprehend. Which meant we didn’t understand a thing he said.

A superior command of language is a true gift. Often earned by years of study. But if your audience doesn’t understand…well, as Rod Machado would say, “Bad thing.”

I desire to be understood, even if I end up being wrong about what I’ve said. I want you to be able to understand me. And part of being understood is using words properly. So… help me out… electric engine or electric motor?

About Ben Sclair

Ben Sclair is the Publisher of General Aviation News, a pilot, husband to Deb and dad to Zenith, Brenna, and Jack. Oh, and a staunch supporter of general aviation.

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Comments

  1. Jay says

    September 2, 2018 at 10:05 am

    So…When someone blows by you on the highway at 120mph, do you say, “that
    Boy must have a certificate to fly!”

  2. Simon says

    September 1, 2018 at 9:58 am

    You mentioned license or certificate. To be correct you are “licenced” to fly but you are issued with a “license” to prove it.

  3. Dean Merritt says

    August 21, 2018 at 3:10 pm

    Also a boat with engine is a motor boat

  4. Dean says

    August 21, 2018 at 3:08 pm

    But its department of motor vehicles not dep of engine vehicles.. and sign says no motor vehicles not no engine vehicles.

  5. Tim Harvey says

    August 21, 2018 at 10:09 am

    It sounds like it is an issue of which uses the combination of a fuel.

  6. Henry K. Cooper says

    August 21, 2018 at 6:28 am

    Let’s make it simple……

    There is no such rating as an “airframe & motor” mechanic.

  7. EC says

    August 20, 2018 at 1:50 pm

    There’s 7 minutes I’ll never get back.

  8. Phil says

    August 20, 2018 at 10:48 am

    If you Google the etymology of the two words, you find that motor comes from “late Middle English (denoting a person who imparts motion): from Latin, literally ‘mover,’ based on movere ‘to move.’ The current sense of the noun dates from the mid 19th century.
    Engine, on the other hand, come from Middle English (formerly also as ingine ): from Old French engin, from Latin ingenium ‘talent, device,’ from in- ‘in’ + gignere ‘beget’; compare with ingenious. The original sense was ‘ingenuity, cunning’ (surviving in Scots as ingine ), hence ‘the product of ingenuity, a plot or snare,’ also ‘tool, weapon,’ later specifically denoting a large mechanical weapon; whence a machine (mid 17th century), used commonly later in combinations such as steam engine, internal combustion engine .
    So a motor moves you, while an engine is a product of ingenuity. There, solved it for ya.

  9. Pat Martin says

    August 20, 2018 at 10:48 am

    The only reason the two words are now sorta interchangeable for people who aren’t familiar with grammar is that people not familiar with grammar or their mother tongue are using the words wrong.

    An engine creates power from a process and then applies that power

    A motor simply converts power created somewhere else to some sort of force.

    Think of it this way. You have a ship. A nice big one. It has a huge diesel engine or two. Those engines burn diesel fuel to extract the energy to create power to turn something that creates electricity. Then that electricity is fed into electric motors that apply that power into some force, turning a prop in this case. Same for trains.

    Not for hydroelectric dams. Water via gravity (the power) is used to turn turbine motors used to turn generators to create electricity. There’s no extraction of power as with the fluid of gasoline or diesel. It’s just a conversion of gravity to power/force. Same with a windmill. It’s sound stupid to call a windmill generator an engine.

    Same for rocket motors. This is where it gets complicated. Rockets motors create motion just like engines so some would say from this that motors are a kind of engine. And that may well be where the future grammar on this is headed.

    Engines extract energy creating motion and motors simply convert it. Motors cannot turn themselves the way engines can because motors do not extract energy. Unless you consider rocket motors.

    The confusion has largely been driven by the custom car people who are shade tree mechanics and for some reason prefer the term “motor”. The truth there is cars have both. The gasoline engine and then the motors for things like AC fans and anything else that runs on electricity generated by the engine.

    The confusion is also caused and continued because both terms are used as metaphors very often. The confusion is also made far worse because the two words are very often used as metaphors. Since 99% of Americans don’t have a definition of the word “metaphor” either the meanings of engine and motor continue to have less and less boundaries.

    There are three elements to determining proper grammar and one is historical usage. So if everyone starts calling engines motors then the dictionaries change their definitions.

    My dad never cared a bit for grammar but he was in the last class at Chanute when the USAF still made aircraft mechanics learn the entire plane. One practice that he didn’t like was confusing the two terms engine and motor.

  10. Henry K. Cooper says

    August 20, 2018 at 8:01 am

    In the ’40’ s and ’50’s, an aircraft mechanic was an “A&E mechanic (airframe and engine). This was later changed to “A&P” (airframe and powerplant). There never was an “airframe and motor mechanic”.

    In the days before earning my A&P certificate, ( yes, Part 65 calls it a certificate), I was taught that the thing that lives on the far side of the firewall (the prime mover) is an engine. This includes a piston engine that burns avgas or Jet A, or a “suck ‘n blow” that turns a prop or blows it out its rear. If it’s a device that is powered by electricity to raise and lower the gear, turn a vent fan or such, it’s a motor. With the advent of electrically powered aircraft, I feel that the thing that turns the prop will be an (electric) motor.

    The quandary is why General Motors and Ford Motor Company are called as such when they manufacture piston engines.

    Then there is Continental Motor Corporation and Lycoming Engines that both manufacture piston engines! Tomayto- tomahto.

  11. Chris Ishmael says

    August 20, 2018 at 6:26 am

    I’m usually a stickler when it comes to correct terminology but this is one debate that has been going on far, far longer than I’ve been alive and it’s not going to be resolved any time soon. I can come up with multiple references throughout history where both terms have been used to describe either electric or combustion powered machines. The terms are interchangeable depending on the context and who’s referring to it and have been for well over a hundred years.

  12. Ed Fogle says

    August 20, 2018 at 4:39 am

    Technically Ben’s emailer is correct in his statement of the difference between engine and motor. However, when I ride a bike trail I usually see a sign stating “No motorized vehicles allowed”. Following the strict definition would that mean electric golf carts are prohibited but gasoline engine ones are OK? I then remember the government agency that licenses us to drive cars is the DMV, Department of Motor Vehicles. Don’t they deal almost exclusively with engine driven vehicles?

    • Jeff Gorss says

      August 29, 2018 at 11:28 am

      A motor converts energy to work. An internal combustion engine is a TYPE of motor — it produces power within itself by converting fuel to work. An electric motor is also a TYPE of motor but doesn’t burn anything to produce work.
      They are both motors. Motor oil, General Motors, DMV, electric motor, motor boat, motorhead — -all OK. Gasoline, diesel, and battery-powered motorized vehicles are all prohibited.
      My point was that an electric motor converts energy produced elsewhere into work.
      A square is a rectangle is a quadrilateral, but a quadrilateral isn’t necessarily a rectangle, nor is a rectangle necessarily a square.
      In the end it all comes back to definitions we agree on, and I disagree with calling an electric motor an engine.

  13. Will says

    August 19, 2018 at 5:25 pm

    Rocket motor, electric motor, gasoline engine, those are the correct terms for FAA testing. Aside from
    that we use slang in this country. So this falls under the Yawn factor! We all know what everyone is
    calling the items so just chill out.

  14. Geremy Kornreich says

    August 19, 2018 at 4:21 pm

    Originally from automotive use, probably, but I always heard the “engine” was the longblock – the minimum assembled unit to start and run. Engine block, crankshaft, pistons, cylinder heads, carburetor(s), water pump, starter, etc.

    The “motor” was the complete assembly with the usual bolted-on attachments, like alternator, power steering pump, air conditioning pump, and maybe external stuff like radiator.

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