What is considered a mid power rocket engine?

[Alfard23]

Hello all!

What is considered a mid power rocket engine?
It's a bit confusing, some say an E engine while others say an F and G engine.

 

[neil_w]

There's no "official" dividing line between them. Some say E, some say F. To me, D is definitely LPR, F is definitely MPR, and E can swing either way.

 

[astronwolf]

There is no standard, but very loosely defined, mid power are/were model rocket motors that were not Estes but were not High Power. At one time Estes had just the mighty D. Aerotech and other vendors filled the mid-power market that Estes could not. Since those days, Estes experimented with the E15, then the E9, and now finally, they have a mid-power motors too (E and F). Earliest references to "mid-power" on rec.models.rockets were made in 1993, but the context of the references implied that the term was already commonly understood.

 

[cerving]

Once you get your L3, an L2 is "mid-power"...

 

[Hobie1dog]

E,F, and G

 

[Alfard23]

Thanks for the answers! Very interesting an E motor is therefore a doubtful case but F is definitely Mid Power

 

[cwbullet]

E,F,G, but I think the midpower pads at our launch go GHI.

 

[rharshberger]

E,F, and G has long been considered Midpower and A-D is Lowpower everything else is High Power.

 

[KenECoyote]

As per TRF:

 

[Funkworks]

NAR says E is mid power:

https://www.nar.org/standards-and-testing-committee/standard-motor-codes/

 

[Alfard23]

NAR says E is mid power:

https://www.nar.org/standards-and-testing-committee/standard-motor-codes/

Thanks Funkworks! I see this as the best answer for now.

 

[Huxter]

I see that line between 24mm Es (E12) and 29mm Es (E16)

 

[Steve Shannon]

Hello all!

What is considered a mid power rocket engine?
It's a bit confusing, some say an E engine while others say an F and G engine.

Years ago the FAA actually had model rockets, which were up to 16 ounces and typically flew on A, B, C motors and had almost no restrictions. Then there was mid power, which were above 16 ounces up to 3.3 pounds. There was probably a range of propellant weights also that I don’t remember. Those rockets required a notification of the nearest airport. Above that was high power which required a waiver.
That changed and now there’s no more mid-power as far as FAA restrictions. There’s only Class 1, 2, or 3.

 

[cls]

To me, D is low mid power, because waaay back when, we only had A B C motors in CA. We knew someone's older brother who had a burnt D12. He let me hold it, my hands were shaking.

 

[bjphoenix]

To me, D is low mid power, because waaay back when, we only had A B C motors in CA. We knew someone's older brother who had a burnt D12. He let me hold it, my hands were shaking.

When I started B motors were the largest available, at least the largest that came with delay and ejection charges, but some of them had a pretty big hole in the end.

 

[mtnmanak]

... E can swing either way.

Those damn E motors and their loose morals...

 

[KenECoyote]

Those damn E motors and their loose morals...

The G spots between MP and HP.

 

[jahall4]

Thanks for the answers! Very interesting an E motor is therefore a doubtful case but F is definitely Mid Power

... or possibly even HPR like one of my favs the CIT F240. https://www.thrustcurve.org/motors/Cesaroni/68F240-15A/

 

[Rex R]

Think you mean cti

 

[smstachwick]

The mid-power designation is a tricky one. It’s no longer defined in relevant FAA regulations and the definition is thus somewhat flexible.

However, the NAR Safety Code specifies that model rockets running on an E motors or larger should be launched at least 30 ft away from the flier, range personnel, and spectators. This also happens to roughly coincide with the range where fliers start to use epoxy construction, through-the-wall fin installation, composite motors, launch rails, and other build techniques commonplace in HPR.

Just above the E class are F and G motors, some of which are certified as high-power motors due to sparky propellant or high thrust or both. Some hybrids are made in the G range too. Motor options proliferate in the F and G ranges as well.

Thus, most rocketeers think of mid-power as the E-G range, which is what this forum uses.

Personally, I like this definition because it wouldn’t take much effort to design a rocket that can be flown on a D, E, and sparky F in quick succession, thus qualifying as a low-, mid-, and high-power rocket for each of those respective flights.

 

[Alfard23]

The mid-power designation is a tricky one. It’s no longer defined in relevant FAA regulations and the definition is thus somewhat flexible.

However, the NAR Safety Code specifies that model rockets running on an E motors or larger should be launched at least 30 ft away from the flier, range personnel, and spectators. This also happens to roughly coincide with the range where fliers start to use epoxy construction, through-the-wall fin installation, composite motors, launch rails, and other build techniques commonplace in HPR.

Just above the E class are F and G motors, some of which are certified as high-power motors due to sparky propellant or high thrust or both. Some hybrids are made in the G range too. Motor options proliferate in the F and G ranges too, with

Thus, most rocketeers think of mid-power as the E-G range, which is what this forum uses.

Personally, I like this definition because it wouldn’t take much effort to design a rocket that can be flown on a D, E, and sparky F in quick succession, thus qualifying as a low-, mid-, and high-power rocket for each of those respective flights.

Great answer, thanks!

 

[Alfard23]

Thanks everyone for the answers! I've become a lot wiser.

 

[dr wogz]

and when does is change from 'Engine' to 'Motor'?!

 

[Funkworks]

and when does is change from 'Engine' to 'Motor'?!

Well I've thought this over and looked into it more than I should have, and here's my take again (it's been discussed years ago in another thread).

"Motor" is technically better (because "mo-" stands for "motion"), but people seem to like "engine" for marketing or emotional reasons. "Engine" comes from "ingenium" (ingenuity) and more closely relates to "design".

"Motor" is the thing without any reference to a designer, while "engine" implies someone designed the thing.

A natural propulsion system can be referred to as a motor, but not as an engine (because no one designed it). An artificial propulsion system can be referred to as both a motor and an engine (because someone designed it).

 

[dr wogz]

Well I've thought this over and looked into it more than I should have, and here's my take again (it's been discussed years ago in another thread).

"Motor" is technically better (because "mo-" stands for "motion"), but people seem to like "engine" for marketing or emotional reasons. "Engine" comes from "ingenium" (ingenuity) and more closely relates to "design".

"Motor" is the thing without any reference to a designer, while "engine" implies someone designed the thing.

A natural propulsion system can be referred to as a motor, but not as an engine (because no one designed it). An artificial propulsion system can be referred to as both a motor and an engine (because someone designed it).

From what I remember of the discussion, Vern himself admitted that 'Engine' was the wrong term, but it was what he initially used, and has stuck...

and from my understanding:

• an Engine makes [rotational] motion from a series / set of parts.. That the initial fuel is further processed / used thru a series of steps / mechanical means to achieve the desired motion. It may also have a set of limits or adjustments to refine the process
• a Motor takes that energy and instantly converts it to motion (electric motor: electrons power a magnet, magnet rotates shaft.

 

[loopy]

Once you get your L3, an L2 is "mid-power"...

I'm L2, working on my L3, and I somewhat consider H and small I motors to be mid power...lol

 

[SolarYellow]

and when does is change from 'Engine' to 'Motor'?!

When you buy it from anyone but Estes.

 

[Ronz Rocketz]

A motor is something you can easily take out of the vessel like an outboard motor compared to a diesel engine. So is a Starship Raptor a motor or an engine?

Similarly, a boat is a vessel that you can put on a ship.

 

[Hobie1dog]

I will try to use "motor" from now on.

 

[Handeman]

An engine is like a liquid fueled rocket engine that has moving parts like pumps and valves. Motors are the solid fuel motors that have no moving parts.
At least that is my understanding... YMMV