NSL 2024: A 24" Diameter 1/6th SpaceX Dragon Pad Abort Test

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At least the newly implemented abnormal flight policy and required post flight analysis got a good workout at NSL. It did a nice dance with just a modicum of land snake. All nice and close to the pad. Very cool. :)
 
Jack,

So sorry to see that. But thanks for posting the video.
You have a lot of experience with composite clusters. Any thoughts about how to get double igniters, or smaller augmented igniters, into those smaller nozzles?
Do you think the length of the igniters may have contributed? Were you using the NSL launch system or your own?
Finally, and I know it's early, but any thoughts about a venue to refly?

Again, this was a REALLY difficult project but you definitely did your homework. It's been great watching you work out the problems with the boilerplates. Still believing you can and will make this work.

Steve
Double Igniters - the I40N-P nozzles are just big enough to fit a single e-match, so doubling would be nearly impossible and could lead to a blocked nozzle CATO in my opinion. The e-match option was chosen with advice from Karl at Aerotech. Augmented e-match ignitors were considered, but recent experience of a small sample had a 20% failure rate and concluded as too high of a risk.

Ignitor length - The e-match leads where trimmed to equal lengths, individually connected to a splice port on Splicing Wire Connectors. Ignitors resistance was individually measured with matched pairs installed in opposing motors, variance was small ranged from 1.2 to 1.8 ohms. Total ignition resistance was measured and checked with each ignitor addition. Final state was 0.1 ohm. So, no I don't think ignitor length was an issue.

My thought is e-match burn intensity, directional variance, limited hot gas/burn likely lead to non-simultaneous ignition of the I40N-P's.

Launch system - We used our relay box to power the e-matches, NSL GSE simply closed the relay. Pretty sure power to ignitors/e-matched was not a factor.

Refly? - we'll see.... if everything aligns, perhaps the Tri-Cities Sandblaster event in Pasco, WA over Labor Day weekend. Way too early to say at this point. Acquiring 8 motors could be one of many limiting factors given Aerotech's recent availability announcements.
 
Double Igniters - the I40N-P nozzles are just big enough to fit a single e-match, so doubling would be nearly impossible and could lead to a blocked nozzle CATO in my opinion. The e-match option was chosen with advice from Karl at Aerotech. Augmented e-match ignitors were considered, but recent experience of a small sample had a 20% failure rate and concluded as too high of a risk.

Ignitor length - The e-match leads where trimmed to equal lengths, individually connected to a splice port on Splicing Wire Connectors. Ignitors resistance was individually measured with matched pairs installed in opposing motors, variance was small ranged from 1.2 to 1.8 ohms. Total ignition resistance was measured and checked with each ignitor addition. Final state was 0.1 ohm. So, no I don't think ignitor length was an issue.

My thought is e-match burn intensity, directional variance, limited hot gas/burn likely lead to non-simultaneous ignition of the I40N-P's.

Launch system - We used our relay box to power the e-matches, NSL GSE simply closed the relay. Pretty sure power to ignitors/e-matched was not a factor.

Refly? - we'll see.... if everything aligns, perhaps the Tri-Cities Sandblaster event in Pasco, WA over Labor Day weekend. Way too early to say at this point. Acquiring 8 motors could be one of many limiting factors given Aerotech's recent availability announcements.
That would be TCRs SodBlaster...we have a lot of sand but way more sod! :)
 
Double Igniters - the I40N-P nozzles are just big enough to fit a single e-match, so doubling would be nearly impossible and could lead to a blocked nozzle CATO in my opinion. The e-match option was chosen with advice from Karl at Aerotech. Augmented e-match ignitors were considered, but recent experience of a small sample had a 20% failure rate and concluded as too high of a risk.

Ignitor length - The e-match leads where trimmed to equal lengths, individually connected to a splice port on Splicing Wire Connectors. Ignitors resistance was individually measured with matched pairs installed in opposing motors, variance was small ranged from 1.2 to 1.8 ohms. Total ignition resistance was measured and checked with each ignitor addition. Final state was 0.1 ohm. So, no I don't think ignitor length was an issue.

My thought is e-match burn intensity, directional variance, limited hot gas/burn likely lead to non-simultaneous ignition of the I40N-P's.

Launch system - We used our relay box to power the e-matches, NSL GSE simply closed the relay. Pretty sure power to ignitors/e-matched was not a factor.

Refly? - we'll see.... if everything aligns, perhaps the Tri-Cities Sandblaster event in Pasco, WA over Labor Day weekend. Way too early to say at this point. Acquiring 8 motors could be one of many limiting factors given Aerotech's recent availability announcements.
Jack,

Wonderful response. Your level of experience is so helpful for me to understand the issue. I really hope you get a chance to refly.
 
Is there some way to restrain the rocket (capsule?) from lifting off for a second to allow all engines to ignite? Stake the pad down and have some kind of release mechanism on a timer. Might still get some instability at uneven burnouts, but it will be moving generally upward at that point and the fins might help keep it from full on tumbling
 
Soooo... How can I get a 1/12 scale shell? I would love to have some flatcar loads for my 1/12 scale ride-on trains. I have a few empty flatcars looking for loads right now... :D
 
every rocket has a pad....even if its the away cell....

as long as its safe to fly
Back in post eleven I expressed my concern about this project. My primary concern was the simultaneous ignition of eight high power motors. As I also indicated in that post, I have considerable experience flying Pad Abort models.

Since 2006, when Sandman and I built and successfully flew our models, I've watched numerous posters come and go with similar projects. I have never seen another fly successfully. Hence, my skepticism when I saw this project first posted.

But in spite of the fact that this project failed at NSL I would like to be clear that I would absolutely let this project fly at any launch I was in charge of. Unlike virtually any of the other similar projects I've followed over the years, this one was exceptionally well thought out, and a huge amount of effort was put into addressing the obvious areas of concern and flying appropriate subscale boiler plates. The 1/6 scale version was not flown until the 1/12 scale boiler plate flew successfully.

Any question I've asked along the way has been answered with great thought, and in many cases with a level of experience that I don't have. The recent post with answers about nozzle sizes and possible igniter changes was, again, really knowledgeable and thoughtful and appropriate. In 18 years, this is the first pad-abort-style project that I have seen that really should succeed, and I believe actually will if they make another attempt.

In spite of that very ugly video, I would let this project fly at any launch I was in charge of. This is an extremely difficult project but this thread has demonstrated that this is the team to be able to accomplish it. Kudos for all the great work so far. Hopefully I can be there when the success happens.
 
Back in post eleven I expressed my concern about this project. My primary concern was the simultaneous ignition of eight high power motors. As I also indicated in that post, I have considerable experience flying Pad Abort models.

Since 2006, when Sandman and I built and successfully flew our models, I've watched numerous posters come and go with similar projects. I have never seen another fly successfully. Hence, my skepticism when I saw this project first posted.

But in spite of the fact that this project failed at NSL I would like to be clear that I would absolutely let this project fly at any launch I was in charge of. Unlike virtually any of the other similar projects I've followed over the years, this one was exceptionally well thought out, and a huge amount of effort was put into addressing the obvious areas of concern and flying appropriate subscale boiler plates. The 1/6 scale version was not flown until the 1/12 scale boiler plate flew successfully.

Any question I've asked along the way has been answered with great thought, and in many cases with a level of experience that I don't have. The recent post with answers about nozzle sizes and possible igniter changes was, again, really knowledgeable and thoughtful and appropriate. In 18 years, this is the first pad-abort-style project that I have seen that really should succeed, and I believe actually will if they make another attempt.

In spite of that very ugly video, I would let this project fly at any launch I was in charge of. This is an extremely difficult project but this thread has demonstrated that this is the team to be able to accomplish it. Kudos for all the great work so far. Hopefully I can be there when the success happens.
I agree with all of your statement Gus, the prototype was flown at a launch I was both Launch Director and RSO of and I know the fliers on the team well, this project was well thought out and executed.

IMO the only thing that could have been done to improve reliability of ignition was to use CTI motors instead of AT motors, but given the availability of CTI motors that was probably no choice since none of our local suppliers have a large selection of suitable motors in the quantities they need. If they choose to fly it at SodBlaster it wont be an issue as far as I am concerned.
 
Back in post eleven I expressed my concern about this project. My primary concern was the simultaneous ignition of eight high power motors. As I also indicated in that post, I have considerable experience flying Pad Abort models.

Since 2006, when Sandman and I built and successfully flew our models, I've watched numerous posters come and go with similar projects. I have never seen another fly successfully. Hence, my skepticism when I saw this project first posted.

But in spite of the fact that this project failed at NSL I would like to be clear that I would absolutely let this project fly at any launch I was in charge of. Unlike virtually any of the other similar projects I've followed over the years, this one was exceptionally well thought out, and a huge amount of effort was put into addressing the obvious areas of concern and flying appropriate subscale boiler plates. The 1/6 scale version was not flown until the 1/12 scale boiler plate flew successfully.

Any question I've asked along the way has been answered with great thought, and in many cases with a level of experience that I don't have. The recent post with answers about nozzle sizes and possible igniter changes was, again, really knowledgeable and thoughtful and appropriate. In 18 years, this is the first pad-abort-style project that I have seen that really should succeed, and I believe actually will if they make another attempt.

In spite of that very ugly video, I would let this project fly at any launch I was in charge of. This is an extremely difficult project but this thread has demonstrated that this is the team to be able to accomplish it. Kudos for all the great work so far. Hopefully I can be there when the success happens.
Many canted tractor motored projects have flown succussfully on this forum. All black powder Estes motors. Lakeroadster flew a Mercury Redstone capsule, I have flown many abominations like a crazy train , tapeworms, Avro Lancaster (8 motors) and many other warbirds and critters.

Lots of traditional canted motors in high power, Duces and Tres upscales using blue thunder and a touch of thermite. Not hard at all, tractors are very stable. It is just getting all the motors to light and come up to power simultaneously.

All the clubs in Colorado, SLVR, TRIPOLI, NCR and SCORE have flown as bad or worse. The top men and women can handel it. :)
 
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