Motors or Engines?

[Aksrockets]

Or just say an A8-3. I don't say motor, I don't say engine, I say CTI H410.

Eh hemmm...

 

[Rich Holmes]

Looking up an engineering term in an English dictionary is not the best way to understand the engineering technical definition and rationale for that definition since they do not have the space to explain technical concepts fully (nor do they understand them quite often).

In different communities words mean different things: try telling a physicist you're "doing work" when you're holding a 100 pound weight up off the ground, or "not conserving energy" when you leave the refrigerator door open. And don't even get me started on "theory", whose differing definitions have a significant impact on public vs. scientific views of evolution.

A general English dictionary will give you the colloquial definitions of "motor" and "engine". An engineering dictionary will give you the engineering definitions.

We're not speaking either colloquially or as engineers, though; we're speaking as rocketry hobbyists. In that community both terms are accepted, roughly equally.

 

[rocketgeek101]

Mostly I call them motors, but it's not uncommon to here me refer to them as engines.

 

[BobH48]

If I use an engine hook on my motor mount, does it mean I can use both motors and engines ?

 

[jadebox]

If I use an engine hook on my motor mount, does it mean I can use both motors and engines ?

I generally use the term "motor," but "motor hook" sounds absolutely foreign.

"Engine mount" sounds okay to me, but "engine retention" is a mouthful.

-- Roger

 

[blackbrandt]

View attachment 152721

Eh hemmm...

And...
2013 motors:
AT 38-360 I357T (342 NS)
CTI Pro-29 6 grain H399WT (282 NS)
AT 38-360 H178DM (283ns)
CTI Pro-29 3 grain H410VM (168NS)
CTI Pro-29 3 Grain 138G106-14A (138ns)
CTI Pro-29 1 Grain 55F29-12A (55ns)
AT 24-40 E28 (40 NS)
(2) Estes D12-3's (34ns)
(5) Estes C6-5 (45 NS)
(2) Estes B4-2 (4ns)




Total Newton Seconds for 2013:


Your Point?

 

[CarVac]

I think we should call them "Temporarily potential impulse".

"Temporarily potential impulse mount"

"Temporarily potential impulse hook"

"Temporarily potential impulse retention"

"I-class temporarily potential impulse"

Instead of cases, they'd be "directing housings" as in:

"Reloadable temporarily potential impulse directing housing"

 

[Bazookadale]

Yes but a Quest C6-5 motor is very different from an Estes C6-5 engine

The important thing to remember is that an A8-3 motor is going to produce the same result in an Alpha III as an A8-3 engine.

-- Roger

 

[jadebox]

Yes but a Quest C6-5 motor is very different from an Estes C6-5 engine

Ooops ... I didn't think about that distinction.

-- Roger

 

[cobra1336]

Detroit "Motor City" Ford "Motor" Co. Locomotive "Engine"

 

[billspad]

Just in case you think this debate is new, read this article from the September 1945 Journal of the American Rocket Society. Evidently the editor wasn't in agreement with the author because the article on the Baka that follows contradicts him.

 

[DRAGON64]

Jet-propelled suicidal rocket motors...

 

[ThirstyBarbarian]

I like engine, the mouth finishes better when you say it, motor leaves the mouth unfinished.

That condition is known as "motor mouth."

 

[gizza2]

They both sound highly mechanical to me but engine seems undeniably so. As such I stick with motor.

 

[Daddyisabar]

I think we should call them "Temporarily potential impulse".

"Temporarily potential impulse mount"

"Temporarily potential impulse hook"

"Temporarily potential impulse retention"

"I-class temporarily potential impulse"

Instead of cases, they'd be "directing housings" as in:

"Reloadable temporarily potential impulse directing housing"

DoublePlusGood

 

[cerving]

From this text, it would seem that any rocket propulsor would be an "engine", because it is using some kind of self-contained fuel as its sole means of providing motive power. A "motor" such as an electric motor is converting one form of energy (electricity) to motion, but of course it could be argued that a battery feeding an electric motor is no different than fuel/oxidizer tanks feeding a LF rocket propulsor.

The debate rages on...

Just in case you think this debate is new, read this article from the September 1945 Journal of the American Rocket Society. Evidently the editor wasn't in agreement with the author because the article on the Baka that follows contradicts him.

View attachment 152805

 

[WillMarchant]

Rocket Propulsion Elements by Sutton and Biblarz has liquid engine and solid motor. I asked Oscar Biblarz if he knew of any historical evidence for this distinction and he said no. He just said they put it in because it was industry practice. It is also my experience that "professional" rocketeers tend to use solid motor and liquid engine.

I suggested to the chair of the UND Space Studies department that trying to track this down might make a good M.S. thesis for a space studies student. I don't know if anything ever came of that...

However, I think Estes has always used "engine" and so that might be a compelling case for using "solid engine" in the hobby rocketry domain...

 

[shreadvector]

Rocket Propulsion Elements by Sutton and Biblarz has liquid engine and solid motor. I asked Oscar Biblarz if he knew of any historical evidence for this distinction and he said no. He just said they put it in because it was industry practice. It is also my experience that "professional" rocketeers tend to use solid motor and liquid engine.

I suggested to the chair of the UND Space Studies department that trying to track this down might make a good M.S. thesis for a space studies student. I don't know if anything ever came of that...

However, I think Estes has always used "engine" and so that might be a compelling case for using "solid engine" in the hobby rocketry domain...

There is a story behind the use of "Engine" by Estes. I think Vern may have mentioned it in one of the historical articles.

 

[Bazookadale]

There is a story behind the use of "Engine" by Estes. I think Vern may have mentioned it in one of the historical articles.

In the early days Estes used the term motor https://www.ninfinger.org/rockets/catalogs/estes60/60est0.html

as I recall Vern said Harry Stine said they should be called "engines" so Estes changed terms, but later GHS changed his mind on this

 

[ThirstyBarbarian]

If you are not sure about the accuracy of a technical term that you want to use, the best way to signal that is by adding the word "thingy":

• Motor thingy
• Engine thingy

No one will quibble about your word choice when you use "thingy."

 

[plano-doug]

If you are not sure about the accuracy of a technical term that you want to use, the best way to signal that is by adding the word "thingy":

• Motor thingy
• Engine thingy

No one will quibble about your word choice when you use "thingy."

You have to be careful, tho. Thingy may work fine. But doololly can draw a scornful look.

Doug

.

 

[Area66]

here something funny, on the Transport Canada rules they mix the word engine and motor

 

[ThirstyBarbarian]

According to the Department of Redundancy Department (DRD), the proper term is "motorengine."

 

[bavspaceprogram]

They're both correct. From Merriam Webster.com:

engine - a machine that changes energy (such as heat from burning fuel) into mechanical motion

motor - a machine that produces motion or power for doing work

Can't argue with the dictionary... The best thing to do would be to insert either term in where it fits best, in terms of "roll-off-the-tongueyness". However, there are a lot of sayings that rely on one of those, and if interchanged would sound stupid.

I feel like someone should resolve this for good, though!

 

[Rich Holmes]

According to the Department of Redundancy Department (DRD), the proper term is "motorengine."

You mean "enginemotor".

 

[Area66]

why not make a poll ?

 

[CarVac]

why not make a poll ?

At this rate, it'd be all write-ins anyway.

 

[Aksrockets]

Compromise: We all make up out own names for engines/motors.

Mine: Woosh tubes.

What's yours?

Alex

 

[CarVac]

Compromise: We all make up out own names for engines/motors.

Mine: Woosh tubes.

What's yours?

Alex

Alex: Woosh tubes.
Me: Temporarily potential impulse.

Who's next?

 

[DRAGON64]

"BOOM Stick!"

[video=youtube;70v3gT9DZ6c]https://www.youtube.com/watch?v=70v3gT9DZ6c[/video]