New Motor Certified

[Alan Whitmore]

The TMT committee met on Saturday, August 13 and certified a new motor, the Aerotech K1800ST-PS. This is a reload kit for the 75/2560 hardware. Total impulse is 2444 +/- 14 N.s and the average thrust is 1776 +/- 22 N. You WILL need one of the stainless steel forward seal discs for this reload, as is the case for most other large Super Thunder motors.
Alan Whitmore, Chair
Tripoli Motor Testing

 

[StreuB1]

@AeroTech @WILDMANRS

Yeahhhh.....gonna need one of these for MWP or even Airfest, if that's even possible. lol

 

[cerving]

It is certified as a crossload in CTI hardware?

 

[rharshberger]

So AT discontinued the K1499W ( I know its a single grain load) and now we have a K1800ST (2 grain load)....sounds like a fair trade to me, besides I like Super Thunder and Warp 9. Thank you Aerotech!

 

[krislhull]

Could be a fun motor for my Astrobee... If only I could get one in the next few weeks...

 

[Alan Whitmore]

It is certified as a crossload in CTI hardware?

Not that I know of. Cross-certifications have always been one of those areas where the process is clear to me, but the actual details about what has been x-certed to what hardware remains murky. If anybody would like to clarify chapter and verse of specific x-certs, I would be glad to hear it.

Alan

 

[rharshberger]

I thought all the certified crossloads were loads that CTI made for AT after the fire at AT, no other loads have be cross certified since...I may be way wrong though.

 

[JohnCoker]

Thanks Alan! (Very consistent thrust curve between the tree firings.)

 

[Steve Shannon]

I thought all the certified crossloads were loads that CTI made for AT after the fire at AT, no other loads have be cross certified since...I may be way wrong though.

Ellis helped AT by making their motors after the fire. They were not cross certified though.
CTI submitted 75 and 98 mm reloads together with AT cases. Those were the first cross certifications, meaning they could be used with either AT or CTI cases. They never provided them to Aerotech though; they were competing against AT.
More recently Aerotech submitted reloads that can be used with either AT cases or CTI cases.
So both AT and CTI make reloads that they have certified in their competitor’s cases.

 

[cerving]

I thought all the certified crossloads were loads that CTI made for AT after the fire at AT, no other loads have be cross certified since...I may be way wrong though.

CTI made loads for AT? That's a new one to me... the notice that AT sent out in 2016 when they ditched the Medusa nozzles for 75mm loads said that ALL 75mm AT loads are cross-certified for CTI hardware. I suppose that if you have an older load with a Medusa nozzle then it would not be cross-certified, but I'm sure that AT would love to sell you the appropriate single-throat nozzle (of course, they'd much rather sell you the whole motor set...)

 

[rharshberger]

Ellis helped AT by making their motors after the fire. They were not cross certified though.
CTI submitted 75 and 98 mm reloads together with AT cases. Those were the first cross certifications, meaning they could be used with either AT or CTI cases. They never provided them to Aerotech though; they were competing against AT.
More recently Aerotech submitted reloads that can be used with either AT cases or CTI cases.
So both AT and CTI make reloads that they have certified in their competitor’s cases.

Good to get that straight, thanks Steve!

 

[jimzcatz]

This is indeed a load for the 75/1280 (one grain) hardware. Yes, I was there and loaded the last one. Its an INCREDIBLE motor!!!

 

[rharshberger]

This is indeed a load for the 75/1280 (one grain) hardware. Yes, I was there and loaded the last one. Its an INCREDIBLE motor!!!

2560 or 1280, Alan's post said 2560 casing.

 

[jimzcatz]

2560 or 1280, Alan's post said 2560 casing.

I realise that, but I was there. I swear that was the single grain case I loaded but as usual, I may be mistaken. I guess it's best to wait for Alan to confirm whether I am nuts or not.

 

[rharshberger]

I realise that, but I was there. I swear that was the single grain case I loaded but as usual, I may be mistaken. I guess it's best to wait for Alan to confirm whether I am nuts or not.

Just making sure, it could have been either. Alan was the one making the official announcement lets make it right. As for you being nuts, not likely.

 

[AeroTech]

I realise that, but I was there. I swear that was the single grain case I loaded but as usual, I may be mistaken. I guess it's best to wait for Alan to confirm whether I am nuts or not.

This is for the two-grain 75/2560 case. The grains are bonded in the liner.

 

[jimzcatz]

Thank you for the clarification. I'm definitely getting blind in my old age. I sincerely apologize for starting this. I should have went straight to Alan.

 

[rfjustin]

@WILDMANRS, I'll need (2) K-1800's please... oh and the 75/2560 hardware as well...

 

[jmasterj]

I uploaded the thrust curve to Thrust Curve. Eyeball-averaged, but it came out very close to the high-level data already there.

ThrustCurve Hobby Rocket Motor Data

Model and high-power hobby rocket motor data for flight simulation and reference.

www.thrustcurve.org

I really enjoyed Super Thunder yesterday, so this will be on my list to order on Black Friday (along with the J615 and K2050).

 

[tjsnakez]

I will definitely be picking one of these up!

 

[Alan Whitmore]

Thank you for the clarification. I'm definitely getting blind in my old age. I sincerely apologize for starting this. I should have went straight to Alan.

We certified the K750ST for the one-grain 75/1280 hardware back in May of 2022. I think I publicized that test shortly thereafter. A

 

[jimzcatz]

Ahhh, makes sense now. Thanks

 

[crossfire]

We certified the K750ST for the one-grain 75/1280 hardware back in May of 2022. I think I publicized that test shortly thereafter. A

So is this reload available?

 

[Alan Whitmore]

Ellis helped AT by making their motors after the fire. They were not cross certified though.
CTI submitted 75 and 98 mm reloads together with AT cases. Those were the first cross certifications, meaning they could be used with either AT or CTI cases. They never provided them to Aerotech though; they were competing against AT.
More recently Aerotech submitted reloads that can be used with either AT cases or CTI cases.
So both AT and CTI make reloads that they have certified in their competitor’s cases.

This is an excellent opportunity to clarify a detail. It is my impression that a specific reload kit must be tested in a specific set of hardware (which might be made by the manufacturer of the reload kit - a regular or ordinary certification - or might be made by another manufacturer - a cross-certification). Cross-certifications by class or type, for example ALL CTI 38mm 4 grain I motors, regardless of propellant type, certified for use in AT 4-grain 38mm cases, never took place, nor did the manufacturers intend for such usage to happen. Is this correct?
I ask this because I have recently been doing a lot of certifications of Aerotech Super Thunder single-use and reloads. This is an unusually stout and fast-burning propellant, and as a potential flyer, I would want that specific reload to have been developed and tested for certification in the specific hardware that I planned to use to put in my rocket.
Those of you who know me know that I have not flown a commercially manufactured motor (except for some Estes B4's and C6's) since 2014, but knowing what I know, I would never try to fly the new K1800ST in anything other than an approved 75/2560 case. I want to make it clear that this is not an official Tripoli policy or recommendation, it is my personal opinion ONLY.

AW

 

[WILDMANRS]

@WILDMANRS, I'll need (2) K-1800's please... oh and the 75/2560 hardware as well...

I have the hardware but can’t order the reload yet

 

[WILDMANRS]

So is this reload available?

K750 is available I sold out of them in one day and have more on the way

 

[StreuB1]

This is an excellent opportunity to clarify a detail. It is my impression that a specific reload kit must be tested in a specific set of hardware (which might be made by the manufacturer of the reload kit - a regular or ordinary certification - or might be made by another manufacturer - a cross-certification). Cross-certifications by class or type, for example ALL CTI 38mm 4 grain I motors, regardless of propellant type, certified for use in AT 4-grain 38mm cases, never took place, nor did the manufacturers intend for such usage to happen. Is this correct?
I ask this because I have recently been doing a lot of certifications of Aerotech Super Thunder single-use and reloads. This is an unusually stout and fast-burning propellant, and as a potential flyer, I would want that specific reload to have been developed and tested for certification in the specific hardware that I planned to use to put in my rocket.
Those of you who know me know that I have not flown a commercially manufactured motor (except for some Estes B4's and C6's) since 2014, but knowing what I know, I would never try to fly the new K1800ST in anything other than an approved 75/2560 case. I want to make it clear that this is not an official Tripoli policy or recommendation, it is my personal opinion ONLY.

AW

Your comment about unusually stout and fast burning propellant.....

Based on the numbers, as Tom (Binford) commented. Super Thunder appears to be a very close match to Vmax. Which I can attest to since I flew the K750ST and yeah, it ROARS like Vmax does. It got everyone's attention.

Cannot wait to fly my L2500ST and M4500ST at Airfest.

 

[StreuB1]

I have the hardware but can’t order the reload yet

Don't forget about little ole me!!!!

Lets keep an open dialog on when those K1800's become available. ;-)

 

[rharshberger]

Your comment about unusually stout and fast burning propellant.....

Based on the numbers, as Tom (Binford) commented. Super Thunder appears to be a very close match to Vmax. Which I can attest to since I flew the K750ST and yeah, it ROARS like Vmax does. It got everyone's attention.

Cannot wait to fly my L2500ST and M4500ST at Airfest.

Now I just need me some 24mm sticks of Super Thunder love...to replace my F240Vmax loads.....and of course a case to put it in....

 

[jimzcatz]

Regarding Alan's question. The only loads cross compatible,weather certified or not is 75 and 98mm. No other loads will work in the other guys hardware. CTI includes RMS O-rings in their 75 and 98mm loads,which I commend. If not certified, most will work but might have to be classed as Research Aerotech tested come of their loads in CTI hardware and as such they are certified. Thats how I understand the state of compatibility.