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Well, that is true. Still, there has been no info from CTI since then- granted the fire occurred and as such would have made this a minor point.

I do believe that this issue is going to just exist- it is the nature of very rapidly burning propellant to extinguish a delay grain

Why not just add an altimeter?
 
Cos the nose cone with the altimeter in it for that rocket just buried itself in the weeds at Bong :)

Joking or is he actually a Bong flyer? Remember- if you can fly rockets at Bong you can fly rockets anywhere.
 
I do believe that this issue is going to just exist- it is the nature of very rapidly burning propellant to extinguish a delay grain

Why not just add an altimeter?
Vmax has been very popular with many members of my club who just want to fly it in a simple rocket with motor ejection. And they did so successfully for years -- it seems like something changed, perhaps. CTI had the only fast propellant that had a delay, and I think that brought them extra market share they wouldn't have had otherwise. Once they've recovered from the fire, perhaps they'll look into this.
 
Well, that is true. Still, there has been no info from CTI since then- granted the fire occurred and as such would have made this a minor point.

I do believe that this issue is going to just exist- it is the nature of very rapidly burning propellant to extinguish a delay grain

Why not just add an altimeter?

i think the issue is that CTI was never directly told about the issue. How this could happen to a motor type and no one picks up the phone and talks officially is just amazingly unprofessional. Oh right... they're volunteers. What craziness am I thinking.

full disclosure.... I'm a Loki fanboy who sold all his CTI gear to buy EX hardware. So... no dog in this fight, but still shocked.
 
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I was told that no-one officially approached CTI requesting that they "fix" anything. It was also suggested that there may be an easy "fix", which was to simply offset the top grain slightly, and that the impact on the performance would be negligible. This discussion was unofficial.

Yes, they were.

Jim

I'm sure people told them... but the question is did NAR or TRA officially and formally inform them of an issue?
 
i think the issue is that CTI was never directly told about the issue. How this could happen to a motor type and no one picks up the phone and talks officially is just amazingly unprofessional. Oh right... they're volunteers. What craziness am I thinking.

full disclosure.... I'm a Loki fanboy who sold all his CTI gear to buy EX hardware. So... no dog in this fight, but still shocked.

I do not know if it was communicated formally or otherwise to CTI, but I can try to find out. Please understand that I have been involved with TMT for all of a couple of months so what has or has not been done before that time is difficult to ascertain.
 
I do not know if it was communicated formally or otherwise to CTI, but I can try to find out. Please understand that I have been involved with TMT for all of a couple of months so what has or has not been done before that time is difficult to ascertain.

I'm assuming that entries into motorcato get provided to the vendors, right? I never personally had this issue, but I told CZTeacherman to report it when it happened to his rocket (in post 57 ), even if there was no damage.
 
I'm assuming that entries into motorcato get provided to the vendors, right? I never personally had this issue, but I told CZTeacherman to report it when it happened to his rocket (in post 57 ), even if there was no damage.

Glen (right?)I am not sure who is entirely on the list that receives info from Motorcato, but I will try to find out.
 
I was TMT for a few years. I never received a single motor failure report.
I would tell people to fill it out, even hand them the form, didn't happen.


M
 
i think the issue is that CTI was never directly told about the issue. How this could happen to a motor type and no one picks up the phone and talks officially is just amazingly unprofessional. Oh right... they're volunteers. What craziness am I thinking.

full disclosure.... I'm a Loki fanboy who sold all his CTI gear to buy EX hardware. So... no dog in this fight, but still shocked.

Like Mark, I don't know what notifications were done on this particular issue, but other actions I've seen include a letter sent to the contact chosen by the manufacturer via email and copied to a group that includes NAR S&T, CAR MCC, and TMT. All official letters such as that are signed by the head of the respective testing organization, so for a Tripoli action it would have been the TMT chair. Because this was a joint action taken by NAR S&T and TMT, the letter to the members was signed by both organizations' representatives. The letter sent to the manufacturer was probably also signed by both sets of chairs.
Communications by TMT to motor manufacturers should be kept private by TMT. I think that's appropriate.
TMT's first responsibility is to the people who fly rockets, to allow them to do so with some expectation of safety, reliability, and consistency. Thus, once the decision has been made to prohibit some use of a motor (such as motor deployment) that decision should be communicated to the members as soon as possible. So I believe we would have made the announcement to the members on the same date we notified the contact CTI provided us.
It's not TMT's place to suggest changes to a manufacturer's design or to give the manufacturers a warning before taking an action on an issue that presents an immediate safety issue. Once an issue has been recognized TMT must act to protect the end users.
The G250 was certified by CAR MCC using a variable delay. Anecdotal reports within this thread discuss that the delays used to work and then all of a sudden began snuffing when the motor burned out. Neither TMT nor any of the other testing organizations act upon anecdotal reports; they rely upon MESS reports and communications with manufacturers. That's why it's so very important that MESS reports are submitted. Without them, we have little to go on.
I don't know if the mess reports are available to the manufacturers. Would it be appropriate for one manufacturer to see all the reports on other manufacturers' motors? Would that provide a market advantage? It might be argued that everyone should be able to see the summaries so they could choose which motors to purchase and which to avoid.
It's TMT's job (and S&T and MCC) to sift through the MESS reports and try to spot trends that indicate problems. Sometimes that's difficult to do without knowing how many of a particular motor have been sold. Five catos of a low production motor might be very bad thing whereas five catos of a motor sold in the tens of thousands or more just might be noise. But we don't know production levels.
So I understand it's easy to jump on a public forum and point a finger and express how shocking something is based on rumors and innuendo, but our volunteers are hard working and very passionate about doing the right thing. We will sometimes make mistakes but we will own up to them, learn from them, and improve.


Steve Shannon
 
Like Mark, I don't know what notifications were done on this particular issue, but other actions I've seen include a letter sent to the contact chosen by the manufacturer via email and copied to a group that includes NAR S&T, CAR MCC, and TMT. All official letters such as that are signed by the head of the respective testing organization, so for a Tripoli action it would have been the TMT chair. Because this was a joint action taken by NAR S&T and TMT, the letter to the members was signed by both organizations' representatives. The letter sent to the manufacturer was probably also signed by both sets of chairs.

Steve- from my opinion, you (and NAR, CAR, etc) have done more than enough. I re-opened this thread hoping to see that Cesaroni came back with "Yup- we found the problem, fixed motors will be available at your local dealer soon". Obviously what they do or don't do is their business, and I didn't intend for this to become a finger pointing or shame thread.
 
thanks- i have several quarks on the build pile..I can rebuild my vindicator sport to use electronic ejection- I just wish I didn't have to :)
 
I re-opened this thread hoping to see that Cesaroni came back with "Yup- we found the problem, fixed motors will be available at your local dealer soon".
I think it's pretty likely that with all the other post-fire production problems at CTI, this isn't high on their priority list to look at.
 
My issue with an immediate cut off and notice to members before talking with CTI is that this wasn't a problem that just popped up. It was going on for awhile, and eventually it was decided enough was enough. It was a gradual decision.

Im not trying to be mean or finger pointing here. Just a critical opinion, and I think it's valid. I understand it takes a lot of work to do things like this. If a letter was sent to a contact at CTI, hey that's notice.
 
My issue with an immediate cut off and notice to members before talking with CTI is that this wasn't a problem that just popped up. It was going on for awhile, and eventually it was decided enough was enough. It was a gradual decision.

Im not trying to be mean or finger pointing here. Just a critical opinion, and I think it's valid. I understand it takes a lot of work to do things like this. If a letter was sent to a contact at CTI, hey that's notice.

Well, actually no; you made baseless allegations that didn't reflect what actually transpired.
I've checked. I'm comfortable with what I've been told was done and that's all I'm going to say on the matter.


Steve Shannon
 
I was TMT for a few years. I never received a single motor failure report.
I would tell people to fill it out, even hand them the form, didn't happen.


M

Mark, the online form does work. I have been emailed five individual failure reports in the last couple of weeks.

Mark
 
Well, actually no; you made baseless allegations that didn't reflect what actually transpired.
I've checked. I'm comfortable with what I've been told was done and that's all I'm going to say on the matter.


Steve Shannon

well if no one wants to say what actually transpired, I'll believe what I see. And it's not baseless. Someone posted here CTI was not contacted. I believe that person.
 
David, just for the record here is the release put forth by Steve Lubliner, NAR S&T Chair, and former TRA TMT Chair Paul Holmes on 6-2-16. For the record, I think you are trying to be combative and negative, and are once again doing an excellent job of it.

To our members:

The National Association of Rocketry’s Standards & Testing and Tripoli Rocketry Association’s Tripoli Motor Testing Chairmen are hereby enacting temporary Safety restriction for all Cesaroni Technology, Inc. VMAX reload motors equipped with delay charges.

We have both seen a growing number of VMAX flights using delay only recovery coming in ballistic at our flying fields, due to delay snuffing. It is believed that delay snuffing is likely a result of any extremely high burn rate motor completing its burn with a significant drop in pressure and/or temperature, breaking the burn ‘chain’, extinguishing or ‘snuffing’ the delay slug.

In light of the unpredictable VMAX delay performance and the resulting significant safety issues, we will now require all VMAX motor flights flown at NAR and Tripoli launch sites to have at least one electronic system installed for primary recovery. These electronics need to be able to handle the short G period of these motors to insure “Flight in progress” triggers. The safety restriction will be lifted when the manufacturer has provided documentation to the three motor certification committee chairman which includes the root cause analysis, the corresponding design changes undertaken by the manufacture to address the issue, and implements the necessary changes.

Any questions about this restriction may be sent to your respective organization’s motor test chair

Regards,

Steve Lubliner
NAR Safety Committee Chairman

Paul Holmes
Tripoli Motor Testing Chairman
 
David, just for the record here is the release put forth by Steve Lubliner, NAR S&T Chair, and former TRA TMT Chair Paul Holmes on 6-2-16. For the record, I think you are trying to be combative and negative, and are once again doing an excellent job of it.

To our members:

The National Association of Rocketry’s Standards & Testing and Tripoli Rocketry Association’s Tripoli Motor Testing Chairmen are hereby enacting temporary Safety restriction for all Cesaroni Technology, Inc. VMAX reload motors equipped with delay charges.

We have both seen a growing number of VMAX flights using delay only recovery coming in ballistic at our flying fields, due to delay snuffing. It is believed that delay snuffing is likely a result of any extremely high burn rate motor completing its burn with a significant drop in pressure and/or temperature, breaking the burn ‘chain’, extinguishing or ‘snuffing’ the delay slug.

In light of the unpredictable VMAX delay performance and the resulting significant safety issues, we will now require all VMAX motor flights flown at NAR and Tripoli launch sites to have at least one electronic system installed for primary recovery. These electronics need to be able to handle the short G period of these motors to insure “Flight in progress” triggers. The safety restriction will be lifted when the manufacturer has provided documentation to the three motor certification committee chairman which includes the root cause analysis, the corresponding design changes undertaken by the manufacture to address the issue, and implements the necessary changes.

Any questions about this restriction may be sent to your respective organization’s motor test chair

Regards,

Steve Lubliner
NAR Safety Committee Chairman

Paul Holmes
Tripoli Motor Testing Chairman

Let me make things clear right off because I can see where this discussion is headed . I am completely biased and non supportive of a single manufacture for the sake of this discussion. Mark the letter that you posted is from TRA / NAR . It states that THEY are aware of a growing problem with CTI's VMAX motors and delay snuffing , and require electronic deployment as a solution to a larger problem. I don't see anywhere in the letter any type of evidence that CTI either cares or knows of the problem , or even that they acknowledge the problem with a possible solution . I believe what some people are asking , especially with the MESS reports , about are the manufactures ( CTI in this case ) seeing the reports ? Also , if there is a known problem with a certain type of motor , why are they still allowed to be sold to the general market. Off the top of your head , how many people that fly vmax motors that come with a delay for motor ejection are on this form , and are able to see this message from TRA / NAR ? How many LPR flyers that are buying E/F/G motors that may not be at large launches to fly them do not know they need electronic deployment ? I believe that ALL VMAX motors should be sold as plugged only until a solution to the problem can be found .

Eric
 
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