Oddball rocket . What is it ?

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It was called SPED (Supersonic Planetary Entry Decelerator), and it was a test of a proposed conical heatshield/Aeroshell shape for a Mars lander called "Voyager," before it was scaled down to the Viking landers, and the Voyager name was applied to Mariner Jupiter-Saturn. At launch the "umbrella" was folded against the body, and looked like a ribbed cylinder. The "umbrella" deployed at an altitude where Earth's atmosphere had the same density as Mars's atmosphere, to test the aerodynamics of the shape. Here is a photo of the launch configuration and a diagram of the flight profile:
 

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  • SPED 70-HC-646.jpg
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It was called SPED (Supersonic Planetary Entry Decelerator), and it was a test of a proposed conical heatshield/Aeroshell shape for a Mars lander called "Voyager," before it was scaled down to the Viking landers, and the Voyager name was applied to Mariner Jupiter-Saturn. At launch the "umbrella" was folded against the body, and looked like a ribbed cylinder. The "umbrella" deployed at an altitude where Earth's atmosphere had the same density as Mars's atmosphere, to test the aerodynamics of the shape. Here is a photo of the launch configuration and a diagram of the flight profile:
Makes me wonder why the aeroshell was opened up in the original picture - a ground test maybe?
 
Post to mark this thread for when I need a new Terrier upper stage project.
First, it's a single-stage rocket the "upper stage" is just a separable payload. Second, that's a Castor rocket motor (31-inch diameter) not a Terrier. I believe the missing fin and booster dimensions on this drawing would be the same as for the Trailblazer II.
 

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First, it's a single-stage rocket the "upper stage" is just a separable payload. Second, that's a Castor rocket motor (31-inch diameter) not a Terrier. I believe the missing fin and booster dimensions on this drawing would be the same as for the Trailblazer II.
Thank goodness. I didn't really need another dart to put on my Terrier booster.
 
First, it's a single-stage rocket the "upper stage" is just a separable payload. Second, that's a Castor rocket motor (31-inch diameter) not a Terrier. I believe the missing fin and booster dimensions on this drawing would be the same as for the Trailblazer II.
This must not have been a project with much public visibility because I'm having a hard time digging up any results on google. Even scholarly article links are taking me to more modern aeroshell heat shield information. Do you have links for further reading or maybe list a book with info on the SPED project? Given the age of the project, do you know if the smaller side boosters actually detached or just stayed on for the whole boost?

As for model rocket considerations, even if the shield doesn't deploy and is cosmetic only, that design would be a fun build.
 
Oddball rocket . What is it ?

Brian

View attachment 689694

Thanks Brian! Over the last few years, I've been brainstorming a rocket design that opens up like an umbrella at apogee, so this seems so perfect to model! I now have a new project for this year. :) 👍
 
Thanks Brian! Over the last few years, I've been brainstorming a rocket design that opens up like an umbrella at apogee, so this seems so perfect to model! I now have a new project for this year. :) 👍
It could pop the "umbrella" with a simple burn thread and rubber band setup like many helicopter recovery models. If it comes down in one piece, it wouldn't be quite like the originally intended flight profile, but would absolutely be a crowd pleaser. Especially on a low and slow motor to keep it in sight the whole time.
 
I believe that Chris Timm is the one who dredged up these reports, and I was able to locate links based on the PDF files he sent me:

I searched for TM-X-2671 on the NASA technical reports server to find this:
https://ntrs.nasa.gov/api/citations/19730006315/downloads/19730006315.pdf?attachment=true

I searched TN D-6910 there to find this:
https://ntrs.nasa.gov/api/citations/19720025205/downloads/19720025205.pdf?attachment=true
Excellent info! Not only pictures and diagrams of the rocket and aeroshell, but failure analysis of the parachute! Perfect snow day reading!
 
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