AeroTech Open Thread

[0011001100]

Perhaps motors of similar total impulse but more manageable average thrust.

Something on the order of an N10k in average thrust would still be nice. Would make a great booster for a two stage. Team I am on has a N10k but the supplied glue for the grains into the liner had gone bad so it is just sitting in storage and we ended up flying an Aerotech motor.

 

[Neutronium95]

The H13 is an amazing motor. I flew one yesterday to 17755 feet. I probably won't get the official record, because the printed nosecone cracked on landing, but I'm satisfied with the flight.

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.

 

[AeroTech]

The H13 is an amazing motor. I flew one yesterday to 17755 feet. I probably won't get the official record, because the printed nosecone cracked on landing, but I'm satisfied with the flight.

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.View attachment 560145View attachment 560146

Wow, that’s incredible!! Congratulations!!

 

[Wayco]

The H13 is an amazing motor. I flew one yesterday to 17755 feet. I probably won't get the official record, because the printed nosecone cracked on landing, but I'm satisfied with the flight.

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.View attachment 560145View attachment 560146

Tried my best to keep it in sight with my binoculars, but lost it after about 10 seconds of boost. Awesome flight Daniel!

 

[bad_idea]

The H13 is an amazing motor. I flew one yesterday to 17755 feet. I probably won't get the official record, because the printed nosecone cracked on landing, but I'm satisfied with the flight.

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.

Congratulations! Official or no, that's an astounding feat. Would you consider starting a thread with more details about the rocket and flight?

 

[bunkermonkey9]

Awesome

 

[Handeman]

The H13 is an amazing motor. I flew one yesterday to 17755 feet. I probably won't get the official record, because the printed nosecone cracked on landing, but I'm satisfied with the flight.

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.View attachment 560146

Amazing flight. Congrats!

The way the Kevlar thread is twisted up coming out of the lower part of the nose cone, are you sure it broke on landing? It looks like it might have broke on deployment and the the lower nose cone half twisted up the shock cord on the way down. Just wondering...

 

[Jack Hydrazine]

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.

After taking a look at your rocket close up, yes, it's a bit rough. If you take the extra time to give it a really smooth finish it will definitely increase your altitude.

 

[eJar0k]

Love the H record flights, excellent use of that motor!

On similar long-burn DMS like the I40N, G8/12ST, and J33N (really hoping that certifies as an I), none of them are sold without the printed thrust ring. Would it be okay to sand, cut, or otherwise remove the thrust rings on <75mm DMS in general without making them EX? Official amendment to the instructions would be useful for the Tripoli records committee and California flyers, since there's the risk of a non-warrantied flight otherwise.

I wouldn't expect more SKUs to be added for additional no-thrust-ring motors, so this seems like a good solution for non-EX submin or staged builds, and it seems like this was approved previously.

 

[Neutronium95]

Congratulations! Official or no, that's an astounding feat. Would you consider starting a thread with more details about the rocket and flight?

Just wrote up everything about the flight in this thread.

After taking a look at your rocket close up, yes, it's a bit rough. If you take the extra time to give it a really smooth finish it will definitely increase your altitude.

I was absolutely in a rush when getting the rocket ready to fly. It would be very easy to put a much smoother finish on it.

 

[bad_idea]

it seems like this was approved previously.

Thank you for posting that link. I have bookmarked it. My G12 plans can now revert to 29mm tubing instead of BT55.

 

[SolarYellow]

Thank you for posting that link. I have bookmarked it. My G12 plans can now revert to 29mm tubing instead of BT55.

Not good enough. PDF it so if TRF disappeared, you still have it archived.

 

[bad_idea]

Not good enough. PDF it so if TRF disappeared, you still have it archived.

Good point, thanks. Done.

Alas, BT55, I nearly loved thee. (Actually it's still a good tube for 24mm-powered sport rockets with the Rocketarium retainer.)

 

[Jim Burgess]

After taking a look at your rocket close up, yes, it's a bit rough. If you take the extra time to give it a really smooth finish it will definitely increase your altitude.

Serious flight!

 

[Jim Burgess]

Serious flight!

I’m not a new member btw

 

[cautery]

After taking a look at your rocket close up, yes, it's a bit rough. If you take the extra time to give it a really smooth finish it will definitely increase your altitude.

Just wrote up everything about the flight in this thread.

I was absolutely in a rush when getting the rocket ready to fly. It would be very easy to put a much smoother finish on it.

I get that. I loathe the finishing part of almost everything.... furniture especially. But that is such a small airframe, and the potential returns are significant. Even I would be willing to true/flatten and polish that whole bird to the lightest/smoothest finish I could produce. Who cares what the color is.... flat, straight, smooth!

I want to see you repeat and record that record!

 

[Alan15578]

The H13 is an amazing motor. I flew one yesterday to 17755 feet. I probably won't get the official record, because the printed nosecone cracked on landing, but I'm satisfied with the flight.

I'm thinking that with a few tweaks to the design, a better surface finish, and launching at a high elevation launch site, like the one for NSL this year, 20k might be possible.

View attachment 560145View attachment 560146

Excellent composition with the shadow selfie.

 

[Neutronium95]

At the TRAPHX launch, I also picked up a KBA M3500R reload. This is one of those motors that I found a thrustcurve for, fell in love with, and then was disappointed to discover was out of production.

I wonder if it would be possible for Aerotech to make a similar motor for the 75/7680 hardware. What's really surprising to me is that the M3500 has more than twice the thrust of the only slightly smaller M1550. As far as I know, all manufacturers use the same case thickness in 75mm, so I doubt the M3500 is running at a significantly higher pressure, but that's really the only reason for it's high average thrust that I can think of, unless Aerotech has a faster burning version of Redline that they're sitting on.

 

[tjsnakez]

At the TRAPHX launch, I also picked up a KBA M3500R reload. This is one of those motors that I found a thrustcurve for, fell in love with, and then was disappointed to discover was out of production.

I wonder if it would be possible for Aerotech to make a similar motor for the 75/7680 hardware. What's really surprising to me is that the M3500 has more than twice the thrust of the only slightly smaller M1550. As far as I know, all manufacturers use the same case thickness in 75mm, so I doubt the M3500 is running at a significantly higher pressure, but that's really the only reason for it's high average thrust that I can think of, unless Aerotech has a faster burning version of Redline that they're sitting on.

The original redline load for the 7600 case was the M2900 - which was certified with a significantly lower impulse and thrust that falls more in line as the M1550s big brother. I've always been curious how that ended up as the M3500.

 

[Neutronium95]

The original redline load for the 7600 case was the M2900 - which was certified with a significantly lower impulse and thrust that falls more in line as the M1550s big brother. I've always been curious how that ended up as the M3500.

I think that there was probably a problem with the test equipment. The "M2900" has a similar thrust curve and burn time to the M3500, just less thrust throughout the entire burn. It loses so much impulse due to that reduced thrust that it actually has less impulse than the M1550, despite having a good bit more propellant.



I wonder if Aerotech or anyone at TMT could let us know what the story behind that motor was.

 

[tjsnakez]

I think that there was probably a problem with the test equipment. The "M2900" has a similar thrust curve and burn time to the M3500, just less thrust throughout the entire burn. It loses so much impulse due to that reduced thrust that it actually has less impulse than the M1550, despite having a good bit more propellant.
View attachment 560502


I wonder if Aerotech or anyone at TMT could let us know what the story behind that motor was.

"Please note that due to a data discrepancy between AeroTech's measured static test data and NAR certification data, the M2900R-P is listed in the AeroTech catalog as the M3500R-P. AeroTech plans on having the M2900R retested in the near future to bring the certification and manufacturing test data into agreement."​

 

[SolarYellow]

Here's a link to my vNARCON PowerPoint presentation tonight during the Manufacturers' Forum:

vNARCON 2023 Manufacturers' Forum Presentation

Will definitely be buying an Enerjet Nike-Ram.

Will the nose cone be available as a standalone part?

I've been diving down the Enerjet rabbit hole the last few days for some reason. I'm sure you've discussed internally what other classic kits to release. Would love to see a 1340 kit. Remembering the earliest version had that same nose cone as the Nike-Ram, it would be cool to at least do that. Since Penrose has apparently abandoned the 1340 fin can, retooling it would be kinda neat. Especially double-diamond fins with fillets and a sleeker taper on the forward edge of the sleeve. Ideally, one that could live at supersonic speed the way the old literature claimed the 1340 would go with the "30 lb/second" motor.

 

[AeroTech]

Will definitely be buying an Enerjet Nike-Ram.

Will the nose cone be available as a standalone part?

I've been diving down the Enerjet rabbit hole the last few days for some reason. I'm sure you've discussed internally what other classic kits to release. Would love to see a 1340 kit. Remembering the earliest version had that same nose cone as the Nike-Ram, it would be cool to at least do that. Since Penrose has apparently abandoned the 1340 fin can, retooling it would be kinda neat. Especially double-diamond fins with fillets and a sleeker taper on the forward edge of the sleeve. Ideally, one that could live at supersonic speed the way the old literature claimed the 1340 would go with the "30 lb/second" motor.

I’m pretty sure the ‘Ram will use an existing Quest nose cone for the sake of cost and simplicity.

Retooling the 1340 fin can is a possibility, and like you said it would be good to slightly redesign and strengthen it so it could handle the high speeds. I’ve seen several shed the fins back in the day.

 

[SolarYellow]

Would love to see glass reinforced nylon or maybe higher-temp polymer. Maybe even a thermoset. I suspect the people buying MPR and HPR motors would be willing to pay for it.

I'd also love to see it a slip-fit over 29mm MMT, with the OD matching the 35mm tube. Instead of the forward end being a giant step change increase in the airframe diameter throwing a big ol' shock wave across the fins when it goes supersonic, step it down from the BT OD to a centering ring spigot that locates the back end of the tube. Maybe another centering ring at the front end of the MMT to help keep everything beefy and coaxial.

 

[jmasterj]

@AeroTech, how far down can the delay on the J615ST-20 be drilled? The tool will only take you to -8 (12 seconds), but can you safely drill it down to -12 (8 seconds) or even lower?

 

[AeroTech]

@AeroTech, how far down can the delay on the J615ST-20 be drilled? The tool will only take you to -8 (12 seconds), but can you safely drill it down to -12 (8 seconds) or even lower?

Probably, but we can’t recommend that because it wasn’t certified in that configuration.

 

[AeroTech]

We tested a brand new RMS motor today, an N4000W-PS in a new RMS-98/20480 case! This White Lightning propellant motor generated 18,540 N-sec of total impulse, 5,320 N maximum thrust with a 4.6 second burn time. The motor was developed for collegiate teams competing in the 30,000 foot altitude event at IREC. A formal product news release with additional information will be made available later this week.

 

[crossfire]

Nice

 

[jmasterj]

Probably, but we can’t recommend that because it wasn’t certified in that configuration.

Got it, thanks (and looked up the cert doc just to make sure I understood). Guess I'll find out when I try it.

 

[jjwb22101]

We tested a brand new RMS motor today, an N4000W-PS in a new RMS-98/20480 case! This White Lightning propellant motor generated 18,540 N-sec of total impulse, 5,320 N maximum thrust with a 4.6 second burn time. The motor was developed for collegiate teams competing in the 30,000 foot altitude event at IREC. A formal product news release with additional information will be made available later this week.

I assume it's premature to ask about other loads for the case?