What's your favorite CTI propellant?

[TD Sky]

Hello, everyone. I normally fly AT White Lightning and Mojave Green, but am thinking seriously about switching the CTI 29mm and 38mm motors. What are some of the things you like about those reloads? Any favorites? Thanks.

Tim
TRA 9256 L2

 

[BsSmith]

I do not have any CTI cases, but I too am thinking of getting some for a few reasons.

#1 reason- Skidmark

#2 reason- Ease of assembly

#3 reason- Skidmark

#4 reason- Wide variety of propellant choices with AMW Pro-X

#5 reason- Skidmark (as you can see I like Skidmarks, the AMW Pro-X ones are some of the loudest motors of their size.)

 

[n3tjm]

Accurate delays (assuming the delay drill too was made right)

 

[cjl]

I fly mostly Aerotech, but I do like the CTI motors. I'd say my favorites are the White Thunder (great in bigger loads especially - the L2375 will always be among my favorite motors), Skidmark, and Blue Streak (good flame, and quite a bit slower than most blues). The Imax also looks nice, but I've only seen one fly. Of course, I'm still partial to White Lightning and Mojave Green too.

 

[Viperfixr]

Hello, everyone. I normally fly AT White Lightning and Mojave Green, but am thinking seriously about switching the CTI 29mm and 38mm motors. What are some of the things you like about those reloads? Any favorites? Thanks.

Tim
TRA 9256 L2

In my opinion, there's nothing wrong with AT in those sizes, but Pro38 is EASY; I have every Pro38 case available. If I were to L1 cert again, being a newbie and not wanting the stress of putting together an H/I motor for the first time, I would unquestionably go the Pro 29/38 route.

You just cannot screw it up easy (although I am sure someone will come up with that lone exception), and they light on the pad instantly--no chuffing, just instant on. And, the clean-up takes 1 minute to do--wet paper towel around the inside of the forward end of the case, and that's it.

The Red Lightning is very nice, the Classic not as smoky as White Lightning, the Vmax is a real kicker--love it, and the Smoky Sam like the FJ. I have not tried any other formulations. The adjustable delay is awesome, and easy to do. They might cost a bit more than comparable size ATs, but the convenience is worth it at times (i.e. when I want to fly more in a day, ease of use, or if it's an important/high stress flight).

All that said, I will not sell my AT stuff and still fly it as much or more now that I am used to building them (RMS) from 18-38mm.

 

[TD Sky]

Thanks everyone - excellent help. I will definitely be trying some CTI motors this summer.

 

[MarkM]

You just cannot screw it up easy (although I am sure someone will come up with that lone exception),

But, plenty have....by inserting the reload into their rocket sans casing. Makes for an interesting fireball on the pad.

While I fly AT in the smaller sizes and Gorilla in 54mm and up, I'm interested in trying out the new Blue streak, especially in the 29's. Deep blue flames are cool and CTI seem to have thrust curves similar to other propellants. I'm not a fan of the quick Blue Thunder from AT.

 

[Donaldsrockets]

I've only flown the Classic and Smoky Sam motors. The Classic is nice because of the long burn and the SS was really cool due to the thick black smoke trail.

But, I'm really itching to fly some CTI Skids!!!

 

[SpartaChris]

You just cannot screw it up easy (although I am sure someone will come up with that lone exception), and they light on the pad instantly--no chuffing, just instant on.

Yeah, you can screw it up. I've seen instances where people forgot to put the reload package in the case. Let's just say you wind up with what amounts to being a nice blow torch burning out both ends!

As for CTI motors being "instant on", we proved otherwise this morning. Lee Scott flew his 6" Thor with a central K1275 and 3 J380 Sparkies from AMW-ProX, all lit from the ground.

To light the central motor we used thermite with an e-match. The sparkies had the standard CTI ignition slug in the top, also lit with an e-match.

When the button was pressed, the K1275 lit instantly. The sparkies didn't come to life until the rocket was about 1,000' in the air. Again, all were lit using e-matches on the ground.

Instant on? Yeah, not so much.

 

[MarkM]

But, I'm really itching to fly some CTI Skids!!!

Donald!!! I lieu of Harold's absence I'm forced to act on his behalf
You better look for another field to enjoy your skids. Come up to Tampa..maybe Harold will give ya a ride one weekend; he usually comes.

 

[Donaldsrockets]

Donald!!! I lieu of Harold's absence I'm forced to act on his behalf
You better look for another field to enjoy your skids. Come up to Tampa..maybe Harold will give ya a ride one weekend; he usually comes.

Hey, did I say you could join this party???

Just kidding, that's what I plan on doing.

 

[MarkM]

Hey, did I say you could join this party???

Just kidding, that's what I plan on doing.

Please do..would be good to have ya. Next weekend could be huge with potentially as many 5 or 6 L3 certs and one other M flight. I know I'll be there just for the spectacle.
Paul Robinson often comes so he may have any skids you want on site.

 

[madsen]

It would appear that CTI users like Skidmard motors. That is great. I love fireworks too. However, I am waiting for the bad news. I have a bit of experience with the old "Firestarter" motors. They were fun to watch--but they started fires. Under normal circumstances, if one is carefull, a motor that emits a shower of sparks can be perfectly safe--if one has water and fire fighting equipment on hand. However, every so often a rocket will go up about 10-20 feet and make a 90 degree turn--hug the ground and travel four or five hundred feet and dive to the ground. Normally, when this happens--it is not a major problem. If this were to happen with a motor that emits a shower of sparks--this could be a disaster. Many launch areas have lots of dried up weeds. I would hate to have to fight a 500' fire--it could be a problem. As someone once said: "This is Rocketry, not fireworks" My launch area is covered in dead weeds most of the year. I honestly do not think it is a good idea to fly a motor that could potentially cause a major problem. If someone wants to fly a sparky type motor where there is no fire danger--that is great. However, most of the sparky type motors that I have seen flown were flown in areas where fire was a danger. Every time I hear the LCO announce a sparky type motor-I cringe. They have the ability to seriously hurt the hobby. The last thing that we need is more bad publicity. I will not even mention the liability implications.

 

[MarkM]

While I agree with your sparky assessment in concept, I think you're overreacting a touch. Yes, a major fire could be very problematic. If you are that concerned about sparky motors and the danger they pose to the field you fly at, you should bring your concerns to the LCO. The LCO has the authority to deny a flight/motor for any reason he/she sees fit. The majority of LCOs/prefects are very cognizant of the potential fire hazard sparky motors pose. One club I fly with bans sparkies completely at all times - no exceptions for precisely the reason you mentioned..lots of dry weeds even after a rain storm. The other clubs have a sparky ban enforced as warranted by the LCO based on field conditions. For about three or four months this year, the Tampa Tripoli allowed no sparky flights. Now that the rains have started in central Florida, the sparky ban is lifted, but can be enforced whenever field conditions mandate it. All clubs I fly with have fire suppression equipment and fliers on alert.

 

[madsen]

Thank you MarkM for your thoughtful answer. I assumed that the Skidmark fans would issue an all out attack on me. One other point that bothers me is "perception". We have lots of people in Washington that do not really like us. I imagine our attorneys attempting to win friends and influence people--and having a politician or regulator hand them a picture of a Skidmark showering sparks all over the place. It would be very hard to convince someone that we are serious rocket enthusiasts when it might appear that our rockets would better belong in a 4th of July celebration. I love fireworks. Whenever I get a chance to go to Texas--I try to go just before the 4th--and I let loose. I just think that the presence of "sparky" type motors does us no good. In my humble opinion, we are better off sticking to black smoke, red flame, and green flame rockets. In the past week we have seen that the news media is ready to pounce on us whenever the opportunity arises. I just do not want to give anyone the oportunity.

 

[cjl]

It would appear that CTI users like Skidmard motors. That is great. I love fireworks too. However, I am waiting for the bad news. I have a bit of experience with the old "Firestarter" motors. They were fun to watch--but they started fires. Under normal circumstances, if one is carefull, a motor that emits a shower of sparks can be perfectly safe--if one has water and fire fighting equipment on hand. However, every so often a rocket will go up about 10-20 feet and make a 90 degree turn--hug the ground and travel four or five hundred feet and dive to the ground. Normally, when this happens--it is not a major problem. If this were to happen with a motor that emits a shower of sparks--this could be a disaster. Many launch areas have lots of dried up weeds. I would hate to have to fight a 500' fire--it could be a problem. As someone once said: "This is Rocketry, not fireworks" My launch area is covered in dead weeds most of the year. I honestly do not think it is a good idea to fly a motor that could potentially cause a major problem. If someone wants to fly a sparky type motor where there is no fire danger--that is great. However, most of the sparky type motors that I have seen flown were flown in areas where fire was a danger. Every time I hear the LCO announce a sparky type motor-I cringe. They have the ability to seriously hurt the hobby. The last thing that we need is more bad publicity. I will not even mention the liability implications.

Actually, the CTI motors have smaller chunks of titanium than the old Animals did, and as a result, the sparks don't linger nearly as long. I've seen quite a few of the new CTI skids recently, and not one of them started a fire. On the other hand, at our launch site (national grasslands), when someone flew one of the old Animal skids, a small grass fire was a near certainty (and as a result, they were eventually essentially banned on all but the wettest of days). In that respect, they seem safer than the old Animals. Besides, with some common sense, the risk is fairly small. You definitely don't want to fly them in a field of large dry weeds for example, as MarkM pointed out.

 

[Donaldsrockets]

Thank you MarkM for your thoughtful answer. I assumed that the Skidmark fans would issue an all out attack on me.

No, you happen to have a very valid point. Even I personally am very fascinated with them, I can also realize when they can and cannot be flown safely and would never fly one in a field that was full of dry grass nor would I ever use one for the maiden flight of a rocket regardless of field conditions.

If your field is in as bad of shape as you say it is, then they should NOT be flown AT ALL and have your club officers put an immediate end to all sparky motor flights until ground conditions improve.

Like MarkM said, our club FLASH Rocketry never has and never will allow members to fly any onsite due to tall weeds and I'm talking TALL weeds here. I'm just a tad over six feet tall and some of this crap comes up to or just past my mid section. If a spark from a sparky motor landed in this stuff, it would probably light it up in a heartbeat get out of control in a matter of minutes.

And I'm perfectly ok with this as it is a matter of safety.

Again, I personally love Skids and I'm hoping to fly my very first one very soon but only if the ground conditions are right.

 

[terryg]

Common sense dictates that we do not fly sparkies on our dry desert field on most of our launches. However, after some our monsoon rains you would have a hard time staring a fire with a blow torch and on those rare days we allow it. Other desert launch sites in Arizona, California and Nevada are so barren that there is little to burn. I am looking forward to using a sparky on my next night launch.

 

[brianc]

What's your favorite CTI propellant?

Well after last weekend's launch, I'm diggin' the Red Rhino
and Skids!

This is my 7.75" Megga Mag launching on a central 5 grain
J335 Red and outboard 2grain H123 Skids.


Many thanks to John Seaton and Jimmy Yawn for the photo!

 

[Jeroen_at_CTI]

This is my 7.75" Megga Mag launching on a central 5 grain J337 Red and outboard 2grain H123 Skids.

Great photo. I assume this is the J335 Red?
Jeroen

 

[brianc]

Great photo. I assume this is the J335 Red?
Jeroen

Yup. sorry, fat fingers combined with insufficient coffee.

 

[ECayemberg]

Spartachris,

Flew one of the new 38-6GXL J520 Skids a week ago and had the experience. There were photographers unfamiliar with rockets and I told them that the J520 would probably light much quicker than the AT H123W that I had just launched previously and took a second to come up to pressure. They got a few pictures of igniter smoke after the motor gave a big chuff, paused for a second or two, then took off.

Not necessarily a problem with the motor, but if you're expecting "instant-on" like you find with most CTI motors, you may be up for a surprise as Chris describes. I myself was suprised it chuffed, then sat there for a few seconds.

BrianC: Great photo and cool flight. Always gotta have a Minie Magg in the fleet; and a bigger one to boot is too cool!

-Eric-

 

[Jeroen_at_CTI]

Spartachris,
Not necessarily a problem with the motor, but if you're expecting "instant-on" like you find with most CTI motors, you may be up for a surprise as Chris describes. I myself was suprised it chuffed, then sat there for a few seconds.

The Skidmark propellant has a relatively large amount of binder (to produce the black soothy smoke). It is therefor quite hard to light. I've seen 0.5 - 1 seconds ignition delay, but usually < 0.5s. Several seconds sounds long to me.

In an ideal world we would probably have a larger igniter pellet for the Skidmark propellants. However, that would be another complication for our production people. With so many (new) motors life is hard enough for them ;-). And, as I said typical ignition delays are less than 0.5s.

Jeroen

 

[als57]

What's your favorite CTI propellant?

Well after last weekend's launch, I'm diggin' the Red Rhino
and Skids!

This is my 7.75" Megga Mag launching on a central 5 grain
J335 Red and outboard 2grain H123 Skids.


Many thanks to John Seaton and Jimmy Yawn for the photo!

Thanks for the peek at the J335. Got one sitting here to fly at the next launch. Now if the 5 grain skids would turn up......

Al

 

[daveyfire]

Now if the 5 grain skids would turn up......

They're out there...

 

[MarkM]

Very nice

 

[SpartaChris]

They're out there...

That really was an awesome flight. I think it needs one of the 6XL motors next!

 

[cjl]

The Skidmark propellant has a relatively large amount of binder (to produce the black soothy smoke). It is therefor quite hard to light. I've seen 0.5 - 1 seconds ignition delay, but usually < 0.5s. Several seconds sounds long to me.

In an ideal world we would probably have a larger igniter pellet for the Skidmark propellants. However, that would be another complication for our production people. With so many (new) motors life is hard enough for them ;-). And, as I said typical ignition delays are less than 0.5s.

Jeroen

That's why I'll augment the included pellet (paint the inside of the grain with pyrogen) for my Deuce flight at LDRS (2 Pro54 6G skids). It may be overkill, but I've already watched it climbing away on a single skidmark twice. It won't happen again.

 

[Jeroen_at_CTI]

That's why I'll augment the included pellet (paint the inside of the grain with pyrogen) for my Deuce flight at LDRS (2 Pro54 6G skids). It may be overkill, but I've already watched it climbing away on a single skidmark twice. It won't happen again.

The Pro54 uses a larger igniter pellet. They light a bit quicker, if I recall correctly (too many new motors lately ). Better not take any chances with that flight. Should be pretty cool to watch.
Jeroen

 

[ECayemberg]

The Skidmark propellant has a relatively large amount of binder (to produce the black soothy smoke). It is therefor quite hard to light. I've seen 0.5 - 1 seconds ignition delay, but usually < 0.5s. Several seconds sounds long to me.

In an ideal world we would probably have a larger igniter pellet for the Skidmark propellants. However, that would be another complication for our production people. With so many (new) motors life is hard enough for them ;-). And, as I said typical ignition delays are less than 0.5s.

Jeroen

Jeroen,

Yessir, not a big deal, and no reason to change the design; just something to watch for. I have always been amazed at how easily the Smoky Sam propellant lights for the same reason.

I can't believe all the new loads you guys are cranking out. Please stop, this is getting expensive.

-Eric-