AeroTech Open Thread

[dbpeirce]

I had heard something about Aerotech developing a case forward closure for head end ignition. Is this true?? Anyone know anything about it?

 

[mikec]

I had heard something about Aerotech developing a case forward closure for head end ignition. Is this true?? Anyone know anything about it?

See for example https://www.rocketmotorparts.com/75...sure_Head_End_Ignition/p1577809_20186962.aspx

This head end ignition closure is designed to work with a 75mm AeroTech RMS™ high-power rocket motor casing, an RMS 75mm high-power aft closure and an RMS 75mm Reload Adapter System (RAS) Retaining Ring to enable head end ignition using the P/N LCI100 Low Cost Head End Initiator and an ignition booster charge. This closure is not TRA or NAR certified and may only be used at research and experimental launch activities.

 

[dbpeirce]

See for example https://www.rocketmotorparts.com/75...sure_Head_End_Ignition/p1577809_20186962.aspx

See for example https://www.rocketmotorparts.com/75...sure_Head_End_Ignition/p1577809_20186962.aspx

I actually saw these, but the starters aren’t available abd when they were they only came in bulk for around $1,200 if I recall correctly. Is this going to be the only way to accomplish this or will Aerotech be making something to work with these or one of their own?

 

[StreuB1]

What nozzle does the K270 come with? Traditional or medusa?

I bought one from WM during the holidays sales and plan to use it on a WM M2 with a tail cone closure. If its a medusa, I don't think you can use the tail cone closure with that nozzle due to its short length; it would submerge the nozzle.

Can anyone verify this, please?

 

[tjsnakez]

What nozzle does the K270 come with? Traditional or medusa?

I bought one from WM during the holidays sales and plan to use it on a WM M2 with a tail cone closure. If its a medusa, I don't think you can use the tail cone closure with that nozzle due to its short length; it would submerge the nozzle.

Can anyone verify this, please?

K270 has the big single throat nozzle.

 

[StreuB1]

K270 has the big single throat nozzle.

Thank you!

 

[AeroTech]

I actually saw these, but the starters aren’t available abd when they were they only came in bulk for around $1,200 if I recall correctly. Is this going to be the only way to accomplish this or will Aerotech be making something to work with these or one of their own?

The low cost head end initiators were $30 each when they were available. Our supplier is working on a new version which will be announced when they are released. They will be more than $30, but certainly far less than $1,200…you can get a NASA standard initiator for that.

 

[AeroTech]

I checked my 15 year old J350 grains the other day and they still look like new.

They will stay that way if stored tightly sealed and in low humidity.

 

[StreuB1]

The low cost head end initiators were $30 each when they were available. Our supplier is working on a new version which will be announced when they are released. They will be more than $30, but certainly far less than $1,200…you can get a NASA standard initiator for that.

"Build it and they will come."

I was about to start designing one myself literally this week. If something will be coming out in 2022, I would be inclined to wait.

 

[dbpeirce]

The low cost head end initiators were $30 each when they were available. Our supplier is working on a new version which will be announced when they are released. They will be more than $30, but certainly far less than $1,200…you can get a NASA standard initiator for that.

Is a new initiator coming out or a whole new closure? Can I get one of these closures and just wait for the initiator?? Thanks! The $1,200 dollars I saw was for the bulk amount of starters, and it had said something about not being for sale individually. I guess that would have been for dealers and then they were able to sell them individually.

 

[AeroTech]

Is a new initiator coming out or a whole new closure? Can I get one of these closures and just wait for the initiator?? Thanks! The $1,200 dollars I saw was for the bulk amount of starters, and it had said something about not being for sale individually. I guess that would have been for dealers and then they were able to sell them individually.

It’s just the new initiator. The closures are still available and the new initiators will fit them.

 

[dbpeirce]

It’s just the new initiator. The closures are still available and the new initiators will fit them.

Thank you

 

[SDramstad]

I checked my 15 year old J350 grains the other day and they still look like new.

I flew a 25 year old J350 a week or 2 ago. Little bit of swelling but they fit after peeling the grains a bit. Chuffed a bit but then took off nicely.

 

[StreuB1]

@AeroTech

Do you have a drawing available or one that you can share via PM of the #19001 motor retainer hook? I need a means of motor retention on the sustainer for my Madcow Nike-Apache and the clearance between the airframe, 29mm MMT and the interstage coupler doesn't allow any clearance for motor retention. I have my AT Mustang and the motor hook looks like it would work perfectly. The problem, is my Mustang is BUILT so I cannot measure its length to see if I can incorporate it into the MMT on the Apache sustainer.

If it will fit (pretty sure it will), I need to order a hand full of those. Are they for sale and is there a site that is up that I can order from or do I need to call it in?

Thank you!!

 

[dbpeirce]

@AeroTech

Do you have a drawing available or one that you can share via PM of the #19001 motor retainer hook? I need a means of motor retention on the sustainer for my Madcow Nike-Apache and the clearance between the airframe, 29mm MMT and the interstage coupler doesn't allow any clearance for motor retention. I have my AT Mustang and the motor hook looks like it would work perfectly. The problem, is my Mustang is BUILT so I cannot measure its length to see if I can incorporate it into the MMT on the Apache sustainer.

If it will fit (pretty sure it will), I need to order a hand full of those. Are they for sale and is there a site that is up that I can order from or do I need to call it in?

Thank you!!

How are you igniting that sustainer? The reason I asked about the head end ignition is for that same sustainer. And I’m still not sure how I’m retaining it!!!!

 

[StreuB1]

How are you igniting that sustainer? The reason I asked about the head end ignition is for that same sustainer. And I’m still not sure how I’m retaining it!!!!

You don't have to to HEI, though I would like the option, but I also don't like being shoehorned into one way of doing something. So, I am doing the old fashioned conduit method down the side of the MMT. There is plenty of room to do it! Chinese e-match routes easily through there and clears the interstage sleeve perfectly. I will wire the e-match to a JST connector which will then route into the AV bay to my RRC3. I will run a small kevlar "leash" to the JST connector that will tie to the AV bay eyebolt so when the sustainer ejects, the JST connector pulls apart but doesn't yank on the RRC3's terminal block. At first I thought it was going to be fiddly but its actually not. Only thing you need to do is wire a JST to the end of the e-match but thats not hard to do each flight, just need to prepare it in advance and you will get the connector back each flight.

I am building the AV Bay like CJ did in his build thread; using #4-40 threaded rod. I also bought an AV bulkhead plate from Wildman and flipped the nose cone mounting like CJ did. You gain several inches of unused space in the NC by doing that. I am also mostly copying his interstage design but making a few changes. I am not making the interstage coupler a permanent part of the interstage but instead, screwing them together via #4-40 radial (Frankenstein) bolts[screws]. Same with the coupler into the nose cone.

Check your PM's. I'm sending you a slew of pictures.

I'm telling you, I think the beefy AT retainer hook is the key. I plan on using (2) of them, 180° opposite, just to make sure they hold onto the motor. I am sure thats overkill......we shall see.

 

[terryg]

What is the nozzle throat diameter for an H180W 29mm reload? I do not see this info on line at the aerotech or RCS web sites.

Thanks

 

[tfish]

What is the nozzle throat diameter for an H180W 29mm reload? I do not see this info on line at the aerotech or RCS web sites.

Thanks

.213

Wayback Machine

web.archive.org

Tony

 

[Iamtannorv]

I had a question regarding the 54mm RAS... I picked up the 54 RAS alongside a 54/2560 case for Wildmans black Friday sale with the intent of being able to fly 54/1706 and 54/1280 loads as well but it has occurred to me through some reading that the 2560 case is 854 NS bigger than its predecessor as opposed to the 426 NS gap from the previous 4 cases, does the RAS still work for the 2560 case for 1706 and 1280 reloads, or only for 1706 reloads, or not at all?

 

[jimzcatz]

2560 is 6 grains, 1706 is 4, 1280 is 3.

 

[Antares JS]

I had a question regarding the 54mm RAS... I picked up the 54 RAS alongside a 54/2560 case for Wildmans black Friday sale with the intent of being able to fly 54/1706 and 54/1280 loads as well but it has occurred to me through some reading that the 2560 case is 854 NS bigger than its predecessor as opposed to the 426 NS gap from the previous 4 cases, does the RAS still work for the 2560 case for 1706 and 1280 reloads, or only for 1706 reloads, or not at all?

IIRC the 54mm set comes with two full-length spacers and one half-length spacer to deal with the odd length differences.

 

[Iamtannorv]

So I should be able to fly 1706 reloads using 2 full length spacers, got it, thank you!

 

[jimzcatz]

The odd length spacer is for the 2800 I believe

 

[rocketace]

I had a question regarding the 54mm RAS...

Use a max of 2 spacers. As said above, a short one is needed for the 2800

AeroTech 54mm Reload Adapter System (apogeerockets.com)

 

[3stoogesrocketry]

Use a max of 2 spacers. As said above, a short one is needed for the 2800
View attachment 500367
AeroTech 54mm Reload Adapter System (apogeerockets.com)

This chart is not correct. The 2560 case + 2 spacers will work for the 1706. There is no 5 grain motor at this time.

 

[AeroTech]

Use a max of 2 spacers. As said above, a short one is needed for the 2800
View attachment 500367
AeroTech 54mm Reload Adapter System (apogeerockets.com)

Yes, the chart is incorrect. 2 standard spacers to adapt a 1706 reload to a 2560 case, and two standard spacers and one short spacer to adapt a 1706 reload to a 2800 case.

 

[terryg]

Are there any plans for higher total impulse 24mm motors? Perhaps a 24/100 hobby line case and appropriate reloads?

 

[rharshberger]

Are there any plans for higher total impulse 24mm motors? Perhaps a 24/100 hobby line case and appropriate reloads?

oooh...something along the lines of the SU G110 and G55...love those motors only have one of each left. I really like the F240 Vmax from CTI too, all were an absolute kick in the fincan!

 

[jmasterj]

Yes, the chart is incorrect. 2 standard spacers to adapt a 1706 reload to a 2560 case, and two standard spacers and one short spacer to adapt a 1706 reload to a 2800 case.
View attachment 500521

Looks like you can put a 54/2560 motor in a 54/2800 case with just the short spacer, is that correct?

 

[jimzcatz]

Looks like you can put a 54/2560 motor in a 54/2800 case with just the short spacer, is that correct?

Yes