engines or motors

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havoc821

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It seems that Estes prints "engines" on their casings, but Mr. Stine says in his Handbook of Model Rocketry that they are really "motors". What is your take on this. Who is right?
 
According to the MaxThrust Rocketry Glossary (https://www.maxthrust.net/index.php?module=Encyclopedia&func=displayvol&vid=1):

"Engine" -- A machine that converts energy into mechanical motion. Such a machine distinguished from an electric, spring-driven or hydraulic motor by its consumption of a fuel (from *American Heritage Dictionary*).
See also: motor.

"Motor" -- Something that imparts or produces motion, such as a machine or engine. A device that converts any form of energy into mechanical energy (from *American Heritage Dictionary*).
See also: engine.

I personally think that the rocket variety should be called ENGINES, but nobody around here uses that term much. So, I call them "motors." The terms are used interchangeably.
 
I fully realize that no one is going to lose any sleep over this one way or another, so please don't think I have my knickers in a wad or anything---

I believe the definitions, in engineering terms, go something like this:
Engine: a device WITH moving parts that creates mechanical drive/output power by consuming a yada yada
Motor: a devices WITHOUT moving parts . . etc

Nobody in this hobby has really gotten fussy over the use of these words for the past 50 years. I think they are pretty much considered interchangeable now. There are many other abuses of the English vocabulary and language that are far more important.
 
Websters 2017 Dictionary Definition:

Motor: See Engine

Engine: Any one of a number of mechancal or chemical devices that produce motion and are currently banned by the ATF. (see Constitution)

(am i in a weird mood today, or what!?!!? :D )
 
I like powderburner and kermie's terms! Personally, I prefer to calle them Paycheck Suckers....

Loopy
 
Originally posted by Loopy
I like powderburner and kermie's terms! Personally, I prefer to calle them Paycheck Suckers....

Loopy

well, i'll tell ya....

...i've been to many a launch where they are considered legal tender...

:D
 
Definition 1: A motor is anything that produces or imparts motion. So an engine is a motor. And our rocket motors are too.

Definition 2: An engine is a machine that uses energy to develop mechanical power. I don't think our motors are machines, so they aren't engines under this definition.

Definition 3: An engine is any agent, means, or instrument used to accomplish a purpose. The purpose of our rockets is to fly into the air on a pillar of smoke and fire (at least in most cases). The rocket motor accomlishes this, so it is also an engine under this definition.

I think that #1 and #2 are the typical usage, so they are motors not engines. Until someone comes up with a non-pyrotecnic mechanical ejection scheme, the deployment engine, we prolly can use either term without confusion ;)
 
Originally posted by jflis
well, i'll tell ya....

...i've been to many a launch where they are considered legal tender...

:D

Hopefully they don't become illegal tender :( :mad: :kill:
 
I learned the difference between motors and engines in college but I can't remember exactly what the determining factor is right now. Both produce mechanical energy. I do remember that all engines are motors but not all motors are engines. I think engines are dependant on fluid flow through them.

Rockets use engines according to FAA definitions:

FAR 1.1
"Rocket" means an aircraft propelled by ejected expanding gases generated
in the engine from self-contained propellants and not dependent on the intake
of outside substances. It includes any part which becomes separated during
the operation.

But personally I think engine and motor are pretty much interchangeable. If you say 'rocket engine' I know what you're talking about. If you say 'rocket motor' I still know what you're referring to. But if you say 'whoosh generator' I might think you're talking about the thing that propells your rocket or I might think you're talking about the spicy bean burrito you had for lunch.
 
...i've been to many a launch where they are considered legal tender...


Same here :) Typical CMASS launch I carry $20 cash; plus motors to trade :). I once took a J350 and H220 for a J570 :-D. I love trading motors.
 
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