3 New Aerotech motor certifications and motor files

[markkoelsch]

Hello,

TMT has tested and certified the 3 Aerotech motors. They are two 29mm Super Thunder end burners- the G11 and G12. Also tested was the J520, which is now certified for delay use versus its previously plugged forward closure only configuration.

Complete Aerotech motor files can be downloaded here: https://www.rocketryfiles.com/?p=home&d=FlightSimulation/MotorFiles/ Username and password are both guest. The motor files are also individually available on Thrustcurve.org.

 

[cwbullet]

I cannot wait to fly the G11 and G12

 

[Jmhepworth]

I cannot wait to fly the G11 and G12

Charlie gave me a G12 to demo at Hellfire but the lightest rocket I have with dual deployment is a Wildman Darkstar Mini. It weighs a pound and a half. That’s about twice the weight that is safe to fly with the G12. The thrust curve on the side of the motor says it gets about 4 pounds of thrust initially and then settles in at about 2.5 pounds after the initial kick.

Because the motor doesn’t have an ejection charge, it needs electronics. So I built an Apogee Aspire with dual deploy. It should come in under 12 ounces. It still needs paint, sheer pins, and ground testing, but I should be able to fly it at Airfest this week.

Joe

 

[3stoogesrocketry]

Hello,

TMT has tested and certified the 3 Aerotech motors. They are two 29mm Super Thunder end burners- the G11 and G12. Also tested was the J520, which is now certified for delay use versus its previously plugged forward closure only configuration.

Complete Aerotech motor files can be downloaded here: https://www.rocketryfiles.com/?p=home&d=FlightSimulation/MotorFiles/ Username and password are both guest. The motor files are also individually available on Thrustcurve.org.

Mark , what is the difference between the G11 and G12 ?

Eric

 

[cwbullet]

G12 is 32 mm and the G11 is 29mm

 

[markkoelsch]

Mark , what is the difference between the G11 and G12 ?

Eric

Not a lot. Slightly more thrust for the G12. Probably a better question for Charlie.

 

[markkoelsch]

G12 is 32 mm and the G11 is 29mm

Chuck, this is not the same G12 as the one aimed at the RC crowd. This is 29mm.

 

[swatkat]

Awesome news on the J520!!

Hello,

TMT has tested and certified the 3 Aerotech motors. They are two 29mm Super Thunder end burners- the G11 and G12. Also tested was the J520, which is now certified for delay use versus its previously plugged forward closure only configuration.

Complete Aerotech motor files can be downloaded here: https://www.rocketryfiles.com/?p=home&d=FlightSimulation/MotorFiles/ Username and password are both guest. The motor files are also individually available on Thrustcurve.org.

 

[Jmhepworth]

G12 is 32 mm and the G11 is 29mm

The G12 I have is 29mm.

Joe

 

[burkefj]

I flown both the G11 St and the g12 St 29 mm single-use Motors they're both about 5. 5 Oz, the G11 has maybe about a half pound lower sustain and about 2 seconds longer burn time, and probably a little bit lower Peak off the pad.

 

[jimzcatz]

Didn't one of these demo at NSL as a G8?

 

[markkoelsch]

Didn't one of these demo at NSL as a G8?

The G8 is a different motor, but is very new as well.

 

[caveduck]

I have it on reliable authority that the G11/G12 difference is just the nozzle throat size.

 

[Walter Longburn]

What are the burn times? Thrustcurve shows that they are both 13 seconds.

 

[burkefj]

yeah Mark, are these correct curves, they appear nearly identical, from what I flew the G12 was 13-13.5 seconds and the G-11 was noticably lower sustain thrust and 15 seconds.

 

[grouch]

How will a 13 second burn time effect a 29mm casing? I'm so excited about these two although they are slightly different than what I thought they would be. I was expecting more of a H550 Super sort of thing. Looks like a 38mm paper rocket with an altimeter bay needs to be added to the build pile PDQ.

 

[burkefj]

I ran mine in my glider that had a 32mm paper tube with a 1/16" or so thick paper adapter, the casings came out perfect post burn, they were hot but no burn through etc, no damage to the motor mount tube or the foam that glues the paper tube in place.

How will a 13 second burn time effect a 29mm casing? I'm so excited about these two although they are slightly different than what I thought they would be. I was expecting more of a H550 Super sort of thing. Looks like a 38mm paper rocket with an altimeter bay needs to be added to the build pile PDQ.

 

[burkefj]

Here are Gary's two labels, you can see the peak is below 5 and the sustain on the G12 is closer to 2.5 pounds, the certified thrust curves peak at less than 7 and sustain looks more like 2.25 or below on both of them, the burntime and average look identical in the tested motors....weird...

 

[markkoelsch]

yeah Mark, are these correct curves, they appear nearly identical, from what I flew the G12 was 13-13.5 seconds and the G-11 was noticably lower sustain thrust and 15 seconds.

They are correct per TMT testing. There, and this is off the top of my head, a few Newton’s of impulse difference between the two. The burn times were also almost the same. The same amount of propellant too.

These are well within the variation you can get from motor to motor as allowed in NFPA 1125. Ambient pressure difference between test site and Aerotech’s factory due to elevation could easily account for this alone.

Per testing they are technically a G10 and G11 respectively. If you look at those numbers that means the average thrust difference is about 0.22 pounds between the two.

In essence, you are nitpicking essentially nothing.

 

[burkefj]

Mark I wasn't trying to nitpick all I was asking was whether the thrust curves on thrustcurve. Org were right, I understand about differences in pressure and temperature at the different testing sites its just hard to see the differences between the G 11 and G 12 using the thrustcurve. Org thrustcurves compared to the Aerotech published thrust curves which were noticeably different wrt themselves in terms of peak and sustain, for g11 and g12, not the differences between the thrustcurve. Org published curves and Aerotech curves, I was just asking the question that's all.

 

[grouch]

I am confused as well. They appear to be for all intents and purposes the same motor. What ever, I will end up buying both of them! Now I have a use for my 29mm plugged forward closure that has been bouncing around for years.

 

[markkoelsch]

There was one erroneous point in the G12- not sure how I got it there. It is fixed on thrustcurve.

I goofed up the G11 file- grabbed data from G12 while spending a few hours on this Sunday. I will fix it.

They are very similar.

 

[Jmhepworth]

You won’t need the forward closure. They’re both Single Use DMS.

Joe

 

[markkoelsch]

OK, I have fixed my mistakes now. My apologies...I usually do not make this sort of error.

The J520 is not DMS. It is for the 38/1080 case. It uses a new, single use, forward closure along with the retaining ring from the RAS as I understand it.

As an aside, had a window of about 3 hours on Sunday in which to do rocket stuff. Spent it all doing the certification letters and motor files. Had a window tonight, and ended up using it to fix my motor file errors. I will not have another chance to actually work on a rocket until the weekend if I am lucky...it is very glamorous being the keeper of the motor files.

 

[crossfire]

Mark
You have done a great job for the rocketry world for years

Thank you

 

[Steve Shannon]

OK, I have fixed my mistakes now. My apologies...I usually do not make this sort of error.

The J520 is not DMS. It is for the 38/1080 case. It uses a new, single use, forward closure along with the retaining ring from the RAS as I understand it.

As an aside, had a window of about 3 hours on Sunday in which to do rocket stuff. Spent it all doing the certification letters and motor files. Had a window tonight, and ended up using it to fix my motor file errors. I will not have another chance to actually work on a rocket until the weekend if I am lucky...it is very glamorous being the keeper of the motor files.

Mark,
We all make mistakes from time to time. You always own up and fix them in the rare instances. Sounds like we’re putting too much on you. Is there any way some of this post process can be automated?

 

[Jmhepworth]

Mistakes? Those aren’t mistakes. Spend a half hour watching me build a rocket and you’ll see what mistakes are.

Joe

 

[burkefj]

I knew I wasn't crazy! Thanks Mark for double checking, we all appreciate it. Just as an aside, for me flying a 29 ounce glider, a few more ounces average thrust does make a difference

Frank

 

[markkoelsch]

Mistakes? Those aren’t mistakes. Spend a half hour watching me build a rocket and you’ll see what mistakes are.

Joe

Joe, I appreciate the commentary. They were indeed mistakes, but they are rectified now.

You comment about watching you build a rocket for a half hour to see mistakes made me laugh. It has been a rough couple of day- I needed a good laugh- thanks.

 

[Alan15578]

Thanks for posting the information on these new motors. Unfortunately the are all HPR motors. The motor I was hoping for would essentially be an F10 stretched to 120NS. That is the motor I would buy and fly. It would be the ideal motor, along with two D21s, to fly in single stage Competition evens such as G Super Roc, not that will ever be flown again. In events with staging allowed, an E30 or such would start it off nicely.

Of course the low thrust HPR full G is just the ticket for an awesome Class 1 rocket, when kicked off with an F80 or such first stage. Although that may be pointless with out a visible coasting trail.