In 1 day and 14 hours we will launch our space capsule Tycho Deep Space. I hope you will follow this test live here on Wired.com. Stay tuned!
In space flight, only one thing is certain: no matter the result, it always looks cool!
Space flight or rocketry is a special discipline where all your long hours of work are put to a final test of complete destruction or success. This test is no different. We intend to launch the 500 kg capsule using the Launch Escape System, an 80 kN engine capable of “pulling” the capsule to a height of approx. 1.4 km, releasing it for drogue -- and main parachute deployment and finally a splashdown on water.
As the Flight Director I have the privilege of not only controlling the operation at sea but also operating all flight events. So, I may also be the cause of complete failure if I manage to mess up the flight events. The factor of human error is huge in this mission.
The flight events are as follows:
- LES engine ignition (launch)
- LES system separation at apogee, estimated by FIDO or flight visual
- Capsule drogue deployment
- Capsule drogue release and main chute deployment
- Main chute release after splash down
- Capsule uprighting system
All flight events are vital for the result of this operation. And many questions to be answered on launch day.
Trajectory
I dearly hope we get a straight upwards trajectory providing the highest altitude so we may deploy the main parachutes in good time. But I, and live feed viewers, should prepare for a sideways trajectory proving less height and more horizontal speed.
If we happen to get a very low trajectory with high velocity we might end up with no time for main chute deployment. However, I intend to deploy the main parachutes anyhow just to save the capsule for complete and utter destruction.
Is the entire 8 meter (26 feet) height capsule and LES system configuration capable of withstanding the forces, without breaking up, if it begins to tumble? The capsule/LES configuration is calculated to be very stable. But one thing is theory….
We need at least 400 m for the main parachutes to deploy correctly.
Separation
If we are not able to separate the LES launch tower from the capsule we cannot deploy the capsule drogue and later main parachutes. The entire system will hit water like meteor.
When the 8 detonators, separating the tower from the capsule, is ignited we are simultaneously firing the LES tractor engine adding delta-v on the tower in order to avoid tower and capsule to collide. If the tractor engine does not fire they might end up have the same descent trajectory messing up parachutes deployment and perhaps colliding during splash down. I know they have different drag and geometry and in theory they should get different trajectories. But there is still a change for a nice hit.
Drogue
The drogue is deployed by basically blasting off the top of the capsule using nitrocelluloses providing high pressure. If we fail to ignite the nitrocelluloses nothing will happen and the capsule will hit water at high speed.
Main chutes
The main chutes are deployed by releasing the drogue releasing a pyro-controlled 3-ring system. If this system does work we won’t see any main chutes.
The drogue must have enough power to pull the 3 main vacuum-packed main parachutes from its compartment. It will require a lot of power. Conservative calculations show that the drogue will have a drag force of 1000 N at app 100 km/h and 4000 N at app 200 km/h. Somewhere in between should be enough. However, the main parachutes cannot operate in speeds above 200 km/h or they are likely to be torn.
Main parachute release
The three big main parachutes are attached a single point which is also a quick releasing system. We have to detach the parachutes after splashdown. If the quick release breaks or for some reason is ignited prematurely the parachutes will watch the capsule hit water and later the bottom of the ocean.
I can only say that this test on Saturday is going to be very interesting!
Odds for a perfect mission?
Mmm.. 50%... OK let’s say 60%.. 62%...20%....80%... aargh, heck I don't know...
The capsule Tycho Deep Space was installed earlier today on launch platform Sputnik. Tomorrow will be fueling the rocket and stacking the entire system.
We are still GO for launch Saturday from 4 AM NYC time.
Ad Astra
Kristian von Bengtson
