Lakeroadster's X-FLR6 Rocket Build (AKA the TINTIN Rocket)

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BABAR said:
I think your F motor will overwhelm any asymmetric thrust from your A10-Ps. So you are probably okay no matter what.

Does the A10-P have a smoke charge? If not, it’s gonna burn out quickly and won’t Have a prolonged effect.. I am wondering if you may be better off with aA3-4T longer burn and delay engines. This may give you what I think you want, prolonged 4 smoke trails. You can either have these engines eject (I know, some people don’t like this, but it is a routine thing at many launches.) Or you can put in a sort of vent to allow the ejection charges to discharge safely. One way of doing this is gaps in the centering rings so the charge goes forward and then back down out the bottom of the rocket between motor mount and outer tube.
Click to expand...

Thanks for the reply.

No smoke charge, just off the shelf A10-P with no ejection charge delay.

The Open Rocket simulations show that a short burn is good with the A10's..... then the pod motors expire before the chute deploys.

With the A3-4's the chute deploys while the pod motors are still burning.
 
lakeroadster said:
Thanks for the reply.

No smoke charge, just off the shelf A10-P with no ejection charge delay.

The Open Rocket simulations show that a short burn is good with the A10's..... then the pod motors expire before the chute deploys.

With the A3-4's the chute deploys while the pod motors are still burning.
Click to expand...

Wow, the F44-4 burns and deploys faster than the A4-3!? I hadn’t expected that!

Would 1/2 A3-2T work? Less thrust (which you don’t need, may not even need to cant the motors. If your main doesn’t fire but all three outboards fire, I am not sure your rocket would even leave the pad), more smoke and longer burn, should still be out by time main deploys.
 
BABAR said:
Wow, the F44-4 burns and deploys faster than the A4-3!? I hadn’t expected that!

Would 1/2 A3-2T work? Less thrust (which you don’t need, may not even need to cant the motors. If your main doesn’t fire but all three outboards fire, I am not sure your rocket would even leave the pad), more smoke and longer burn, should still be out by time main deploys.
Click to expand...

Good idea and you are right.

Upon further review I am interpreting the OR simulation wrong. It assumes the recovery device ejects when the earliest ejection charge fires.

A3-4's and 1/2A3-2T's would all work... In order to make the OR sim's work I just need to pick the longest delay possible so the sim doesn't deploy the laundry with the pod motors.

I'll check into modifying the A3-4's and 1/2A3-2T's motor files to delete the ejection.

Thanks for sticking with me on this BABAR.... ;)
 
You’re more than welcome!
As you’ve seen, using the lowest newton mini motors with the right delay gives you pretty much all the show you are looking for with the least risk of a tipsy flight.

Still would love to hear some flight reports on your X wing and Lifting Rockets
 
BABAR said:
Still would love to hear some flight reports on your X wing and Lifting Rockets
Click to expand...

The X-wing is flight ready... still painting The Lifting Rocket. The reality though is Life gets in the way of Hobbies :confused:

We're having an extended winter here... it's snowing right now. There's still over 11 foot of snow on Cottonwood Pass... it is usually plowed and open for traffic by Memorial Day. We got about a foot and a half of snow a week ago.. tore up a bunch of trees. Lumberjack duty.

Here's a photo from yesterday.. CDOT working on Cottonwood Pass
Cottonwood Pass 2019-05-23.jpg
 
Last edited:
Updated the drawings to include the canted 13 mm pod motor mounts.

I'm thinking 2 launch controllers: (1) for the pod motors and another for the F-44 main motor. Initiate the pod motors... once they light then fire the F-44.

Since they are different motor types, there's zero chance the (3) pod motors and the single main motor will light off at the same time.


EOTM Sheet 2 of 7 Rev 02.jpg

EOTM Sheet 1 of 7 Rev 02.jpg EOTM Sheet 2 of 7 Rev 02.jpg EOTM Sheet 3 of 7 Rev 02.jpg EOTM Sheet 4 of 7 Rev 02.jpg EOTM Sheet 5 of 7 Rev 02.jpg EOTM Sheet 6 of 7 Rev 02.jpg EOTM Sheet 7 of 7 Rev 02.jpg
 
They have a core running up through the propellant. The igniter must be placed all the way up (with exceptions, make sure you read and follow the instructions carefully)

Composites need a second to start burning, and then come fully up to pressure before they take off. It makes composite/blackpowder clusters difficult (not impossible, just extra care needed, thus my question)

It is recommended that composite motors be started first before BP motors for this very reason (there's even a question about it on the High Power L2 exams ;/ )

If you light the A10's then the F44, they'll probably burn out by the time it gets going. Worst case scenario, they'll plop it off the rod then the F44 will let'er rip
 
Yup, composite motor first, but...
When the composite goes, it really goes. Doubt if you'll have time to visually react with the second controller.
How does it sim with a BP E12? Then you could light all four at the same time.
 
kuririn said:
Yup, composite motor first, but...
When the composite goes, it really goes. Doubt if you'll have time to visually react with the second controller.
How does it sim with a BP E12? Then you could light all four at the same time.
Click to expand...

147 ft apogee with a single E12.. chute deploys at 70 feet... pucker factor 10 :confused:

303 ft apogee with an E12 and the (3) 1/2 A-3 pod motors

2 ft apogee with just the (3) 1/2 A-3 pod motors.
 
Last edited:
lakeroadster said:
2 ft apogee with just the (3) 1/2 A-3 pod motors.
Click to expand...
:p
So, I'm guessing maybe 1-200 more feet with 3XA10-0s? Decent small field flight.
I'm not discouraging you from trying the BP/composite cluster mix, just saying that the timing is difficult.
Air starts would increase reliability, but make it more complex, since you would have to add electronics.
But you can always fly it on single composite motors for a good ride.
 
Forgot to mention, instead of motors in your outboard pods how about integrating a smoke system?
One controller to ignite the cartridges. After the oohs and aahs from the crowd, use the second controller to send her up.
Can also be lit with a match. Cartridges and holding pods here:
https://www.rcuniverse.com/articles/uncategorized/rc-smoke-system/
Just throwing ideas out there. Rules compliance is on you.
 
In your original statement that you'd like to light the pod motors first, what was the reason? If your looking for a little ground smoke display then the startup delay in the composite might be just the thing. Push one button for all four motors; the BP pod motors light but are too weak to get off the pad; then the composite lights.

Kuririn, earlier in the thread Steve cited the NFPA code for model rocketry sating that flamable payloads on model rockets are forbidden. "Rules compliance is on [the flyer]" as you said, but I think it be a bad idea.
 
Probably the BP pod motors would be just enough to tip the rocket off the launch rail. For a ground smoke effect, you could light a BP motor or two on the ground in a test fixture, separate from the rocket. (or a non-flying smoke system)

But I like the idea of airstarting the BP pod motors.
 
lakeroadster said:
147 ft apogee with a single E12.. chute deploys at 70 feet... pucker factor 10 :confused:

303 ft apogee with an E12 and the (3) 1/2 A-3 pod motors

2 ft apogee with just the (3) 1/2 A-3 pod motors.
Click to expand...

Maybe the 2-foot apogee with the 1/2 A3 motors is a good clue. If you used a Makerbeam launch rail and rail buttons (or a 1/4" rod), you could have a 6-foot rail plus or minus. If the 1/2 A motors fire but not the center F, the rocket never leaves the rail. If the F comes up to power at "apogee" (2'), you still have 4' of guidance for a decent safe flight.

Smoky propellants and Aerotech blues tend to light faster than other propellants. CTI tends to light faster than Aerotech due to the igniter pellet, though that also makes every reload hazmat. A 24mm CTI 3-grain F79 smoky would be an awesome motor for the center, though it may be too much power.
 
jqavins said:
In your original statement that you'd like to light the pod motors first, what was the reason? ...
Click to expand...

If the center motor fires first it's probably not good to have the rocket tethered to the pad via three pod motor leads. May not be a problem, then again might turn the vertical controlled ascent into a game of Russian Roulette.
 
jqavins said:
In your original statement that you'd like to light the pod motors first, what was the reason? If your looking for a little ground smoke display then the startup delay in the composite might be just the thing. Push one button for all four motors; the BP pod motors light but are too weak to get off the pad; then the composite lights.
.
Click to expand...

If “all you are looking for is a ground smoke display,” attach threes smokies around the blast deflector at 120 degrees, NOT attached to the rocket. Clip whip to the composite, one button push, you get the display, center motor goes (or doesn’t), no safety issues or violation, no extra “attachments”.
 
mbeels said:
Oh wow, I really hope to see flight photos posted here. That looks awesome.
Click to expand...

I finally got to fly my version of Tintin's Moon Rocket today at the Tripoli MN launch in North Branch, MN. It flew on an Aerotech J540-RL, weighed 15.5 lbs on the pad, flew to just over 2500 ft in very light winds, and landed a mere 100 yards from the pad. As requested, here are a few pics taken by Jim Fuller.


DSC_1980.JPG DSC_2021_crop.jpg DSC_2024_crop.jpg DSC_2036_crop.jpg
 
BABAR said:
Did it stick the landing?
Click to expand...

Nope. It ended up on its side. There was a definite "thud" when the first fin pod hit the ground. With a bigger chute it might have stayed upright. Maybe next time....
 

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