Higher Initial Impulse?..shorter burn?

[moocrew]

So I've always wondered why no manufacuter has made an engine with a higher impulse but a signifiantly shorter burn time. This would be used to loft slighty heavier rocs but only up to very short altitudes. of course there would need to be enough elevation for the recovery to properly work but it seemed like a logical thought.
Can someone explain to me why this will or won't work...and if it would work why aren't they "produced"?

thnx
-moo

 

[rstaff3]

Don't really know why, maybe reliability or demand. Estes used to make a B14 which was cool. Aerotech used to, and may resume, making the G125. There are more examples in the HPR range. I'm aching for a 100+ N avg impulse motor for their new 38mm G.

 

[Anthony Cesaroni]

An extreme example of a little motor we made for R&D is a G1000. Only tens of milliseconds burn time and a very small motor. Note the mach diamond on the outside of the plume in the attached photo. Propellant burn rate is about 4 inches per second and the Kn is about 40. It sounds like a shotgun blast.

It won't make the shelves at your favorite hobby store unfortunately.

Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
https://www.cesaronitech.com/
(905) 887-2370 x222 Toronto
(410) 571-8292 Annapolis

 

[rstaff3]

Not available, eh? Hey, nobody likes a tease

 

[scm86]

<quote> burn rate is about 4 inches per second </quote>

Wow, you should make some comercial motors with that stuff ;-)

Scott McNeely

 

[rocwizard]

Hey Anthony, any idea when the I600 and K1320 that were demoed at ROC lake 6 might be available for purchase? Those looked like just the thing to punch something up real quick. A fast L or M like that would be cool too.

 

[rstaff3]

Doesn't compete with a G2000, but here's a interesting photo of a Vulcan F675.

 

[Anthony Cesaroni]

Only 38 grams of propellant in the the G1000 slug so It fairs well. Nice shot of the Vulcan unit BTW. I spoke with Scott yesterday and will pass it on.

Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
https://www.cesaronitech.com/
(905) 887-2370 x222 Toronto
(410) 571-8292 Annapolis

 

[Donaldsrockets]

Originally posted by Anthony Cesaroni

It won't make the shelves at your favorite hobby store unfortunately.



Darn

If that motor was made commercially available, I'd be building a killer mach buster just for it :kill:

G1000, That'd test my building skills in a hurry.

 

[Ryan S.]

I made an I600 in a 29mm case, it burned for about .6 seconds. Man it was cool, the rockeet jumped off that pad so fast, the 3lb rocket made it to 3200 feet too

 

[Rocketjunkie]

Originally posted by Anthony Cesaroni
Propellant burn rate is about 4 inches per second and the Kn is about 40.

I want some!! It would be great for large end burners

 

[moocrew]

yeah these should really be massed.
I bet there are more people who would buy them than what most manus. think. Atleast I would.

 

[Ryan S.]

Originally posted by Rocketjunkie
I want some!! It would be great for large end burners

yeah that is some wicked propellant, you could do some cool stuff

 

[Gus]

Anthony,

Welcome to the forum.

Really nice to have your input. One of the best things about this forum is the participation of manufacturers such as yourself.

As for Higher Impulse-Shorter Burn, there are also those of us anxiously awaiting the opposite, the return of Apogee's F-10.

 

[wyldbill]

Originally posted by Gus
As for Higher Impulse-Shorter Burn, there are also those of us anxiously awaiting the opposite, the return of Apogee's F-10.

I'm with Gus here. I like the longer burns. In fact I just ordered a kit with a 75mm mount instead of 54mm so I can fly AMW K365-RR and K450-BB and the AT K560 (and maybe even the Ellis L330 (mmmm.... L330!)) instead of their quicker burn 54mm brethren. The AMW loads are actually cheaper in 75mm for a similar impulse range.

I bought some of the F10s and E6s off the last production run . Savin' an E6 for my Outlander (whenever I finish it).

'course that Pro98 N1100 has my name written all over it. It'd do great in our Delta Project.

-bill

 

[wyldbill]

Flew a Mean Machine over the weekend on an Apogee E6-6. Forever burn to ~1500'.... fun.

 

[ClusterWiz]

If you guys want some fast burn motors, make some of your own zinc/sulfur motors. You used to be able to buy the micrograin motors whick are zinc/sulfer and are just a powder. You can get some sweet flames and some high thrust with those.

 

[Ryan S.]

but ISP sucks and you need a steel casing because the propellant all burns at once then releases all the pressure slowly

 

[rocwizard]

Ummm, NO

Do not mess with these! The risk of injury is not worth it.

No doubt they look cool, but there are many other, much safer ways to get your rocket in the air

 

[daveyfire]

Originally posted by ClusterWiz
If you guys want some fast burn motors, make some of your own zinc/sulfur motors. You used to be able to buy the micrograin motors whick are zinc/sulfer and are just a powder. You can get some sweet flames and some high thrust with those.

...and blow your hand off while making millions of tiny, sharp, steel pieces flying in all directions.

Seen em go. They're like a big smokey cannon shot.

No accelerometer or altimeter can hold on through the ride -- it's just too violent.

And yeah, the Isp sucks.

There was a reason we moved to composite propellants... actually several GOOD reasons. Don't try and relearn history!

 

[moocrew]

yeah i hadn't really planned on making my own motors i dont even have the slightest on how to even start...and im really to lazy I just wanna be able to go out and buy something that can launch my 4 footers and not send them to the moon.....

looks like im back to clustering...

 

[Evil Prince]

I like high impulse, short duration motors. I've flown a few
I flew a couple EX motors as a 54mm L2000 (~2600N-s) and a 29mm I800 (~550N-s). The L was flown in a heavy 4" rocket to 10,975'. Sim said it burned out at 1345' so it coasted for 9600 and change. Long coast flights are cool on video.

I did my L3 on AT M2400 in my Smokin' Rockets Mega Nuke (https://www.urbanplight.com). That bad girl burned out at around 2100' and coasted up to 7419'. THAT looked cool on tape!

Long burn motors are kinda cool too, but the do require a pretty detailed build as the ROT T:W gives you a 7.4 pound total weight...WITH the 3+ pound motor.

 

[gerbs4me]

long burn motors are cool, i do like short burns as well, heck i love em all

 

[shreadvector]

"Model Rocket Motors" cannot have an average thrust above 80 Newtons. That is why a G80 with 62.5 grams of propellant is a Model Rocket Motor while an F101 with fewer grams of propellant is NOT a Model Rocket Motor.

For smaller motors like the Estes black powder type, the cost of making the motors with the deep core (like the B14 or the "semi-cored" B8 and C5) are too high. At least that's what they claim....

Originally posted by moocrew
So I've always wondered why no manufacuter has made an engine with a higher impulse but a signifiantly shorter burn time. This would be used to loft slighty heavier rocs but only up to very short altitudes. of course there would need to be enough elevation for the recovery to properly work but it seemed like a logical thought.
Can someone explain to me why this will or won't work...and if it would work why aren't they "produced"?

thnx
-moo