What is the biggest 29mm cti motor you can use for an l1 cert rocket?

[zeketrimmer]

I have a loc precision Athena kit build with 3rd party launch lugs, parachute, and 4 grain motor mount. I'm going to use it to get my l1 and I want to know how big of a motor I can shove in it before I cant fly for l1 cert because why not

 

[kjhambrick]

You can fly an H-motor or an I-motor up to 640 Ns for Level 1.

For a 38mm CTI reload, that would be 636 Ns if it fits your motor mount.

See ThrustCurve.org > CTI I-Motors

-- kjh

EDIT: oops, missed the 29mm diameter restriction from your title.

Maybe a 4-grain Cesaroni 229H255-14A but you can look for yourself

 

[jsdemar]

I have a loc precision Athena kit build with 3rd party launch lugs, parachute, and 4 grain motor mount. I'm going to use it to get my l1 and I want to know how big of a motor I can shove in it before I cant fly for l1 cert because why not

29mm motor mount in the Athena? If only long enough for a 4-grain:
CTI Pro29-4G 229H255-14A White Thunder is the highest total impulse reload.
Many other up through Pro29-6GXL 382I243-13A White, if there's nothing to block the end of the motor mount tube.

 

[jmasterj]

I can't tell what you're asking - what motors can you fly before getting your certification? Or what is the largest 29mm CTI motor you can use for your certification flight? I assume "largest" means "most impulse," but I could be misinterpreting there too.

The answer to the first question is the G54. The answer to the second question is the I243.

 

[cerving]

AT I205W is a good choice, especially if you don't have AT hardware. They don't get as much of a premium for the 29mm DMS's as they do for the larger motors.

 

[Flare]

AT I205W is a good choice, especially if you don't have AT hardware. They don't get as much of a premium for the 29mm DMS's as they do for the larger motors.

AT I205 is indeed nice. I did my CAR L2 on one.




As far as CTI 29mm goes you can't really go wrong, there are tons of good options. For a 4 grain the H255 is sweet, white thunder is a nice prop. You can go up to some I motors with the 6XL case. I love my Pro29 case, super easy to use and lots of variety and options for motors.

 

[techrat]

I can't tell what you're asking - what motors can you fly before getting your certification? Or what is the largest 29mm CTI motor you can use for your certification flight?
The answer to the first question is the G54. The answer to the second question is the I243.

What what what???
I am not L1, but I have flown G80 -- is that not allowed? I always thought it was by class (A-G); and had nothing to do with other numbers... perhaps that's due to the weight of the propellant? Although I cannot imagine that a G80 weighs more than a G40. If anything, the G40 is a longer burning motor... but uses a slower burning propellant, but should contain the same amount of overall propellent as a G80 in order for the total impulse to equal a G-class motor. So.... what am I missing here?

I think the second question is what the original poster is asking -- as a lot of L1 people are seeking to use an existing rocket for the L1 attempt, so they want to know which motors they can stuff inside a 29mm Motor Mount can they use for their L1, as they move from Mid to High power.... Or, that's my guess anyhow.

 

[jsdemar]

CTI Pro29-4G H255. 231 mm long. $42 (need case)
CTI Pro29-6XL I243. 365 mm long. $60 (need case)
AT DMS I205. 305 mm. $64.

 

[MarsLander]

What what what???

 

[jmasterj]

What what what???
I am not L1, but I have flown G80 -- is that not allowed? I always thought it was by class (A-G); and had nothing to do with other numbers...

Perhaps you should find one of the nice HPR charts that float around here - there are several other numbers that matter. You can definitely fly an AT G80 as an L0. But the OP asked about CTI motors, where the G80 is a sparky motor you can't fly as an L0 (for example).

 

[MarsLander]

I am not L1, but I have flown G80 -- is that not allowed? I always thought it was by class (A-G); and had nothing to do with other numbers

Certain F and G motors also require Level 1 certification for purchase and use (this includes: hybrid motors, motors designed to emit sparks, motors that exceed 80 Newtons average thrust, motors containing 125 or more grams of propellant, or are in rockets weighing more than 1500 grams.

 

[jsdemar]

 

[techrat]

Certain F and G motors also require Level 1 certification for purchase and use (this includes: hybrid motors, motors designed to emit sparks, motors that exceed 80 Newtons average thrust, motors containing 125 or more grams of propellant, or are in rockets weighing more than 1500 grams.

This is true: And yes, I'm flying mostly Aerotech (because I have the RMS 29/40-120 case).
That said, there are Aerotech L1-use motors that also fit in 29mm as far as I know (although that isn't the point of this thread).

 

[UT_Spencer]

Any 29mm CTI should work fine in the Athena for a L1 flight.
My daughter’s has flown on a 6-grain H159 Green and a 6XL H340 Smoky Sam. Great flights on both to about 3000’ AGL.

 

[-Slick-Ice]

How big is your field? How high do you want to fly it?

Before you get your L1 - G80-7T or the G80T-14A and drill it to 6 seconds. H128W is what I would use for a L1 flight but there are a LOT Of good H motors for the Athena. If you need a single use, the H135W is what I used for my L1 in my 3" IRIS.