Rick Newlands 2013 - 2017

Mission safety is paramount. If I was killed or injured, that would be a major failure of our engineering ability. In contrast, proper risk-mitigation strategy and design can give this mission an acceptable level of safety.


There is an element of risk of course, the high energies of rocketry and high speed flight can’t always be channeled and contained. But as M.E. sufferers know, a degree of risk is essential, in their case for recovery from the illness: if one does a little more activity, will it help recovery or cause a painful and distressing relapse? You just have to try it and see.


Balloon ascent


Ideally, I would like to use hydrogen within the balloon. Hydrogen is very flammable however, so when we’re filling the balloon on the ground we will have to take safety precautions to prevent a fire. But they’re just common-sense (no smoking for instance, and no running of car engines). Worst-case it could go bang, but only enough to knock you over. The flames then rise harmlessly into the sky, although a lot of burning plastic balloon canopy then falls to Earth, so we make sure nobody’s directly underneath it, and anyone nearby wears Nomex fireproof clothing and hoods as well as face-masks.


As the balloon is being filled, the rocket booster is filled with nitrous oxide, but at a considerable distance downwind of the balloon. Typical precautions when filling a craft with nitrous are: no naked flames, no mobile phones or tablets to be nearby, wear goggles and gloves, do not inhale any venting nitrous as it’s an anaesthetic.


The aim is to be able to abort the mission safely from any point in the mission, however as with all ballooning, the mission is at-risk from the time of balloon lift-off until the balloon has risen to around 1500 feet altitude. Between these altitudes, there isn’t time or height to successfully activate a parachute or commence a glide of the spacecraft if the balloon bursts. Firing the rocket won’t necessarily work as the thrust vectoring (steering) system is optimised for near-vacuum conditions and won’t work at sea-level. Also, firing the rocket at sea level introduces a host of other risks.


The spacecraft will be in the glide configuration from takeoff until an altitude of around 5000 feet has been reached incase an emergency glide descent is required.


Rocket ascent


Launching from on high from a balloon is much safer than launching vertically from the ground: if the engine quits, you have plenty of time to bail out before impacting the ground.


If anything goes awry with the hybrid rocket engine, I can shut it down instantly by shutting off the nitrous supply valve. Coils of wire wrapped spirally around the combustion chambers will burn through and warn me if hot gas from the engine burns through the walls of the chambers. Monitoring of the pressures in the nitrous tank and combustion chambers can also be monitored for unusual readings that would indcate a problem.


Hybrid advantages:


After shutting down the engine in an emergency, I jettison it and configure the craft for re-entry mode at any height or airspeed.



Protection from Space


The Space capsule is actually two capsules, one nested inside the other with an inch gap between them, for backup because a major cabin leak (a blowout) would be fatal. (Wearing a spacesuit just won’t work: the gloves are far too stiff to fly with). This capsule design strategy is used on Spaceship One and Two, the inner capsule wall is effectively my spacesuit.


What are the dangers of exposure to Space? Depressurisation at high altitude carries the following risks:

Lack of oxygen (hypoxia), which can cause rapid loss of consciousness, depending on the altitude at which the depressurisation occurs. I shall be wearing an oxygen mask.

Decompression illness at altitudes over 18,000 feet. Nitrogen bubbles out of the blood and causes ‘the bends’. I’ll counter this by pre-breathing oxygen for a few hours before liftoff to purge my blood of dissolved nitrogen. However, above 50,000 feet it’s unlikely to offer effective protection.

Ebullism, the spontaneous change of liquid water to water vapour in body tissues at an ambient pressure below 63 millibars. This can occur at altitudes over approximately 63,000 feet and rapidly lead to damage to the lungs and surrounding tissues. If the integrity of the pressurised cabin is breached, it’s essential to maintain the pressure sufficiently high to prevent ebullism and to ensure that the gas composition maximises the chances of injury-free survival. The risk increases with the area of the breach. I’ll consider carrying a ‘repair kit’ to quickly plug small leaks, plus a gas supply to keep the cabin at a low pressure during emergency descent to lower altitudes.

Barotrauma, which is damage to body tissues from a change in pressure. If the capsule depressurises rapidly, the pressure differential between gas in the cabin and gas in the lung could become so great that it may tear lung tissue. This would mean air would leak into the chest (pneumothorax or pneumomediastinum) and gas could get into the tissues (mediastinal emphysema) or circulation, known as arterial gas embolism.

In the event of a depressurisation, medical personnel trained in the treatment of the consequences of decompression at high altitudes would need to be available on the ground to assess and treat me immediately on landing, and specialist medical equipment may be required. Fortunately, Scotland has treatment centres for North sea oil divers on the East coast.

Radiation, Over and above Cosmic rays, a solar flare/storm from the Sun could bathe me in an unacceptably high level of radiation. Generally, various organisations can give a half-hour’s warning of a solar flare (though not always). The best protection is an onboard radiation detector. If the reading becomes too high, I’ll abort the mission and get down to low altitude as quickly as possible.


Re-entry

Infrared cameras will monitor the outside of the craft and warn me of any hotspots forming.

Should the airbrakes fail to deploy, there is still enough drag area to slow me down, although the gees will rise to uncomfortable levels. I can even successfully re-enter with the capsule the wrong way up as in ascent mode, though it’ll be seriously unpleasant.

If some emergency requires me to get down to the ground quickly, I simply keep the craft in its re-entry configuration until near the ground.


Post-re-entry glide and landing

If the craft can’t transform to gliding mode, I have the option of descending by parachute.

If the landing skids fail to deploy, I can still land, though I’ll break the craft and possibly a few bones.

The craft’s low wing-loading (typical single seat microlight) gives a low landing speed (35 knots) to allow landing on grass, or sand beach, so I can land considerably far off-course if necessary.

Mission safety