Monday, August 20, 2012
Reading List: Perigee
- Chiles, Patrick. Perigee. Seattle: CreateSpace, 2011. ISBN 978-1-4699-5713-5.
A few years into the future, while NASA bumbles along in its
bureaucratic haze and still can't launch humans into space, a
commercial “new space” company, Polaris AeroSpace
Lines, has taken the next step beyond suborbital tourist hops
into space for the well-heeled, and begun both scheduled and
charter service in aerospace planes equipped with a
combined-cycle powerplant which allows them to fly anywhere on
the globe, operating at Mach 10, making multiple skips off the
atmosphere, and delivering up to 30 passengers and cargo to any
destination in around 90 minutes. Passengers are treated to
a level of service and coddling which exceeds first class,
breathtaking views from above the atmosphere along the way,
and apart from the steep ticket prices, no downside apart
from the zero-g toilet.
In this thriller, something goes horribly wrong during a flight
from Denver to Singapore chartered by a coarse and demanding
Australian media mogul, and the crew and passengers find
themselves not on course for their destination but rather trapped
in Earth orbit with no propellant and hence no prospect of
getting back until long after their life support will be
exhausted. Polaris immediately begins to mount a rescue mission
based upon an orbital spacecraft they have under development,
but as events play out clues begin to emerge that a series
of problems are not systems failures but perhaps evidence of
something much darker, in which those on the front lines trying
to get their people back do not know who they can trust.
Eventually, Polaris has no option but to partner with insurgent
individuals in the “old space” world to attempt an
improvised rescue mission.
This is a very interesting book, in that it does not read like
a space thriller so much as one of the classic aviation dramas
High and the Mighty.
We have the cast of characters: a crusty mechanic, heroic commander, hot-shot
first officer, resourceful flight attendant with unexpected talents,
demanding passengers, visionary company president, weaselly subordinate,
and square-jawed NASA types. It all works very well, and as long as you
don't spend too much time thinking about mass fractions, specific impulse,
orbital mechanics, and thermal protection systems, is an enjoyable read,
and provides a glimpse of a plausible future for commercial space flight
(point to point hypersonic service) which is little discussed among
the new space community.
For those who do care about the details, they follow. Be warned—some
of these are major plot spoilers, so if you're planning to read
the novel it's best to give them a pass until you've finished
Spoilers end here. (Hide Spoilers)
- In chapter 26 we are told that the spaceplane's electricity is produced by fuel cells. This doesn't make any sense for a suborbital craft. We're also told that it is equipped with an APU and batteries with eight hours of capacity. For a plane which can fly to its destination in 90 minutes, why would you also include a fuel cell? The APU can supply power for normal operation, and in case it fails, the batteries have plenty of capacity to get you back on the ground. Also, you'd have to carry liquid hydrogen to power the fuel cells. This would require a bulky tank and make ramp operations and logistics a nightmare.
- Not a quibble, but rather a belly laugh in chapter 28: I had not before heard the aging International Space Station called “Cattlecar Galactica”.
- In chapter 31, when the rescue mission is about to launch, we're told that if the launch window is missed, on the next attempt the stricken craft will be “several hundred miles farther downrange”. In fact, the problem is that on the next orbit, due to the Earth's rotation, the plane of the craft's orbit will have shifted with respect to that of the launch site, and consequently the rescue mission will have to perform a plane change as part of its trajectory. This is hideously costly in terms of fuel, and it is unlikely in the extreme the rescue mission would be able to accomplish it. All existing rendezvous missions, if they miss their launch window, must wait until the next day when the launch site once again aligns with the orbital plane of the destination.
- In chapter 47, as passenger Magrath begins to lose it, “Sweat began to bead up on his bald head and float away.” But in weightlessness, surface tension dominates all other forces and the sweat would cling and spread out over the 'strine's pate. There is nothing to make it float away.
- In chapter 54 and subsequently, Shuttle “rescue balls” are used to transfer passengers from the crippled spaceplane to the space station. These were said to have been kept on the station since early in the program. In fact, while NASA did develop a prototype of the Personal Rescue Enclosure, they were never flown on any Shuttle mission nor launched to the station.
- The orbital mechanics make absolutely no sense at all. One would expect a suborbital flight between Denver and Singapore to closely follow a great circle route between those airports (with possible deviations due to noise abatement and other considerations). Since most of the flight would be outside the atmosphere, weather and winds aloft would not be a major consideration. But if flight 501 had followed such a route and have continued to boost into orbit, it would have found itself in a high-inclination retrograde orbit around the Earth: going the opposite direction to the International Space Station. Getting from such an orbit to match orbits with the ISS would require more change in velocity (delta-v) than an orbital launch from the Earth, and no spacecraft in orbit would have remotely that capability. The European service vehicle already docked at the station would only have enough propellant for a destructive re-entry. We're told then that the flight path would be to the east, over Europe. but why would one remotely choose such a path, especially if a goal of the flight was to set records? It would be a longer flight, and much more demanding of propellant to do it in one skip as planned. But, OK, let's assume that for some reason they did decide to go the long way around. Now, for the rescue to be plausible, we have to assume two further ridiculously improbable things: first, that the inclination of the orbit resulting from the engine runaway on the flight to Singapore would match that of the station, and second, that the moment of launch just happened to be precisely when Denver was aligned with the plane of the station's orbit. Since there is no reason that the launch would have been scheduled to meet these exacting criteria, the likelihood that the spaceplane would be in an orbit reachable from the station without a large and impossible to accomplish plane change (here, I am referring to a change in the orbital plane, not catching a connecting flight) is negligible.
Posted at August 20, 2012 22:20