During the last couple of weeks I have been working the Launch Escape System (LES) design with Peter Madsen for Tycho Deep Space II. This engine and interface tower, capable of saving the capsule during a failed ascent, has an extensive geometry which must be understood and designed properly for correct stability.
Since we are testing and verifying capsule Cp/Cg issues, very soon, using a vertical wind tunnel the LES system had to be designed and ready for testing as well.
The LES engine is a 72 kg grain, solid propellant, firing for app 1.5 seconds providing almost a 14 g acceleration on the 500 kg capsule and astronaut. The Galcit 61 C solid propellant is being tested at the moment for upper and lower design limits and casting procedures at a fireworks company.
You can download the 3-d files of the LES system here as SolidWorks 2013 and Step. (.zip, 1,5MB)
The LES design phases and testing this summer, are as follows:
- 1/10 scale aerodynamic stability testing at Copenhagen Air Experience (vertical wind tunnel). This will show the relation between center of pressure and center of gravity with and without LES engine propellant.
- 1/3 scale LES static engine testing.
- 2 x 1/3 scale capsule and LES-tower production
- 2 x 1/3 scale flight test of capsule with LES during the Sapphire launch campaign
I short, we aim to fire a couple of 1/3 scale capsule with solid LED motor in 2013. The scope of this launch campaign is ONLY LES-flight stability, not parachutes, radio communication or LES-tower separation. The LES tower (and engine) will be hard mounted the small 1/3 scale capsule and fired. If the system is stable it will return and hit the ocean like a dart and re-surface as a floating buoy.
At the moment the 1/10 scaled models of the capsule and LES-tower is being finalized. Friday we dropped the capsule from a tall building at our facility hoping to get a small glimpse of aerodynamic behavior. It seems to be working. But we know much more from the coming wind tunnel testing.
Last week we visited the vertical wind tunnel at Copenhagen Air Experience. What a cool place and we finally know how to perform the aerodynamics tests on capsule and capsule+LES.
I am still performing CFD calculations on torque(X,Y,Z) on Tycho Deep Space II in SolidWorks, to determine if I can identify Cp on any object we aim to fly. Me previous laptop did not have the muscles anymore but thanks to my friend Samuel Hodge for a private donation used for getting a new laptop with amazing power. Now, I am back on track!
And don’t forget:
Tomorrow, Monday 25, at 1PM Pacific time, 10PM Copenhagen time I will be doing another Reddit Ask Me Anything session, together with Cameron Smith. The topics is space suit, life support and general human factors related to capsule and suit work at Copenhagen Suborbitals. Stay tuned for link!
See you there!
Ad Astra
Kristian von Bengtson
