Mission Profile
The Plan ...
Links
NRL Atmospheric Model
Outer Space Act 1986 (pdf)
Outer Space Act Fees
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First of all, it has to be said that what's posted here should be taken with a large grain of salt and may not in fact happen for a few very good reasons:
1. It may not be possible.
2. It may not be possible given the budget.
3. It may not be legal. I'll attempt to gain all necessary permissions and insurance for everything that I do. If I can't get permission, its not going to happen.
This includes compliance with the UK's Outer Space Act 1986.
That having been said, even if we're prevented from further testing at any stage, its still a fantastic academic exercise and we're aiming to break at least one British amateur rocketry record.
The mission profile is split into either 5 or 6 phases (3a may be dropped), depending on the result of further simulation and actual flight data:
Phase 1 - Rocket Launch
The rocket (complete with fuel, oxidiser, satellite payload, electronics and recovery package) will launch from ground level in whatever country I can most easily obtain permission, but preferably one that has an east-coast bordering either the Pacific or Atlantic.
The pre-orbit portion of the flight will therefore take place over a large body of water with the option for early abort, or late abort / recovery.
Phase 2 - Orbit Insertion
The onboard Inertial Navigation (IN) platform coupled with control-law software will guide the craft into stable low-earth orbit. The orbit is designed to be largely circular with any eccentricity conferring less than a 50Km difference in altitude along the orbital path.
No part of this stable orbit is designed to be lower than 160Km.
Phase 3a - Multiple Earth orbits
Several orbits of the Earth will be made with telemetry to ground confirming the orbital status
Phase 3b - Satellite Insertion
The four satellites will be deployed in sequence from the front of the craft (See Satellite Design).
Because they will already be in a stable orbit, the path of the satellites over the surface of the earth can be predicted. Satellites A and B should also be visible to the naked eye when passing over areas at night providing they are not eclipsed.
Soon after deployment, orbit data together with telemetry frequencies will be made public so that the satellites can be tracked by keen observers.
Phase 4 - De-orbit burn
Small compressed-gas manoeuvering thrusters will orient the craft ready for a short de-orbit burn. The burn will take place at a point in the orbit that allows re-entry over a large body of water.
Phase 5 - Re-entry and recovery
This is a biggie - the most complex part of the entire mission. The most challenging part of re-entry is to choose a profile and energy dissipation method that
results non-destructive thermal decomposition of the airframe, but I fully hope to have the craft back into the lower atmosphere just about intact
(See re-entry simulation).
A pyrotechnic charge fires a small drogue 'chute high in the upper atmosphere which is used to substantially increase the ballistic drag of the craft.
The full recovery 'chute is deployed around 20Km amsl which is stearable via servos attached to wing-warping wires. Providing the IN and electronics has survived, this control system will be able to guide the craft in for a soft landing at a point of our choosing.
We'll, there you go. Say it all quickly and it doesn't seem like a big deal. With regard to the budget you'll be surprised how much you can save if you do all of the work yourself! Also, if it works, the majority of the rocket won't be counted in the budget as it'll be re-useable, but I won't bank on it.
It should be noted that just about all of these phases (except parts of 2, 3 and 4) are individually testable before the event, so it should be quickly obvious if its viable or not. Like I say, if you're going to attempt something like this, you might as well start off trying to go the whole hog.
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Mission Patch
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Very early simulation (failure!)
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NRLMSISE Atmospheric Model
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