Will Astronaut Barbie Fly?

Hello and happy holidays!

In my (perhaps mad) genius I devised and built a rocket to launch my daughter's "Astronaut Barbie" per the attached picture. I am curious if it will work!

Reading posts on this forum, my first main concern was having enough power and enough altitude, but after running OpenRocket now my main concern is velocity off of the rod, which OpenRocket shows as 8.1 m/s.

The rocket:
standard BT70 tube with pre-cut slots for 3 fins; clear BT70 to hold Barbie; and a PNC-56A (BT-70) nose cone
rocket length is 40 inches; the CG (with the Barbie onboard) is about 25 inches from the nose cone tip
weighing it without a motor on my mom's kitchen scale suggests the rocket (no motor) and Barbie combo weigh about 10 oz.
with an Estes F15-8 motor, the weight is about 14.2 ounces...so perhaps it will be about 14.5 with chute and wadding

OpenRocket:
my first time using a simulator, I tried to create a simple setup to approximate the actual rocket
I got put in the dimensions, fins, etc., and got the weight and CG pretty close to my actual measurements

Simulation with F15-8:
Velocity off rod: 8.1 m/s
Apogee: 344 m
Optimum delay: 6.99 s
Time to apogee: 9.41 s

Regarding my first anxiety, that the 8 second delay on the F15-8 would be way too long, at least it doesn't look like it will hit the ground before deployment! But the 8.1 m/s velocity off the rod seems below other posts I've seen suggesting 15 m/s. I am using a standard Estes Max launch pad, which I measure as having a 34 inch rod.

I simulated two other motors...
E16-6:
Velocity off rod: 9.94 m/s
Apogee: 215 m
Optimum delay: 5.36 s
Time to apogee: 7.42 s

D12-3:
Velocity off rod: 10.6 m/s
Apogee: 74.4 m
Optimum delay: 3 s
Time to apogee: 4.63 s

...my preference is to run the bigger F motor for the higher altitude, but the others don't get that much higher velocity off the rod anyway.

I am limited to these motors because I have them on-hand here at my parents' house for the holidays (where all my rocket stuff is kept) with the intention to give it a go because we are only here once or twice a year, so it's make due with what we have.

The simulator gives a "green ball" next to it, though it does have a red "!" which it gives for having a high rate of speed (20.5 m/s) at deployment.

Would welcome any opinions

First and foremost, you're a good dad for trying this.

When I run the rocket specs through Thrustcurve, it warns the F15 will have a 41 ft/second velocity when leaving the rod. Thrustcurve's recommendation is 50 feet per second, or about 15-16 meters per second. The Estes BP F-15s are relatively low average thrust. If it's windy at all, Barbie could have a pretty rough flight ending in a destroyed rocket and dismembered limbs/mussed hair.

I understand you want to do the launch with what you have handy, but I'd recommend not using the F15 and waiting until you could do it with a composite F motor, like an Aerotech F-27. Thrustcurve shows the AT F motors with about an 8-9 second delay and altitudes from 1,000-1500 feet.

I built a 4" upscale Freefall, and flew astronaut Barbie in it. She had her own chute, though. This was on a G75 Blackjack.

But how did she see without a window?
Though I do confess on a separate chute was on my mind for a ver 2.0!

Sounds like a job for an Aerotech F50 to me...

cerving said:

Sounds like a job for an Aerotech F50 to me...

Click to expand...

Or an F42 to save on HAZMAT...

Concur. You get good Dad points for working it up. IMO you get GREAT Dad points for saying this is neat but potentially unsafe, let's go back to drawing board and give Barbie a safe flight!

I’ve seen this fine before but the flyer (who had done several of these) was clear that a name brand Barbie is too heavy and he preferred the dollar store Chinese knock offs which are cheap, hollow, and much lighter. That could change a lot in your sim.


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Since Sindy and Action Man flew... I don't see why not.

[video=dailymotion;x2div2j]https://www.dailymotion.com/video/x2div2j[/video]

If astronaut Chester can fly, I don't see any reason why Astronaut Barbie shouldn't...


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