Two Minutes

The good thing about starship disasters is that they so rarely turn into catastrophes.

Which is to say, sure, you can kill yourself, and you get your crew and your passengers killed, and if you try hard enough, you can go hurtling out of the system into the deep black at ludicrous speed, even while glowing with enough hard rads that no salvor’ll want to touch your hull for the next hundred thousand years. But space is big, its contents are small, and dramatic screw-ups that manage to take out other people by the mucker-ton therefore require sufficiently extraordinary talent that the Fourth Directorate will be crawling all over the site even before the wrecker gets there.

That is unfortunately not the case with interface vehicles, where the gravity well and the atmosphere bend physics all out of shape.

And you are flying, let me remind you, a real starship. Not some dinky aluminum-balloon sounding rocket that will obligingly shred itself into confetti and fireballs if the launch goes wrong; you’re flying maybe 3,000 tons of titanium composite and cerametals – not to mention the hot soup – that will come down hard, and will not come down happy.

This is a problem.

It’s not a problem for long. Well, if you’re flying the vehicle in question, it’s a problem for even less long, but you know what I mean.

Most dramatic engine failures happen very quickly indeed – on the pad, or within the first seconds of flight – at which point the starport disaster team will be on hand to clean up both you and your mess. And if you can keep things running long enough to get to orbital altitude – even on a suborbital trajectory – the odds are good in any kind of developed system that someone has a tug or a powerful OTV that can meet you and drag you the rest of the way upstairs while you get on the horn and have an unpleasant discussion with your insurance carrier.

That leaves the couple of minutes in the middle. Too high and fast for the starport to assist you; too low and slow for help from on high.

So what do you do, in that situation, if your main drive is failing and the auxiliary isn’t kicking in and you’ve got a sad board on all your backups?

Make sure you have the other kind of backup.

See, they don’t leave handling that sort of situation up to the Flight Commander. They know the sort of people who become Flight Commanders, and that they’ll try to save their ship right up until the very last second after it becomes a major incident. As is right and proper, but does not lead to the optimal outcome in this sort of case.

And they don’t leave handling it up to space traffic control, either, as they come from the same kind of dedicated stock that will try to save their traffic up to the very last second, too.

It’s in the hands of one man, titled Downrange Safety, who sits in a bunker at the starport. He has a live feed of all the traffic control instrumentation, everything he needs to see when a launch or landing trajectory has gone grossly off-track and out of safety limits. He has priority “flammifer exigent” access to the orbital defense grid, and to the starport’s launching lasers, and to anything else that might be useful.

He has a fully-automated system with executive authority to blast any incipient disasters right out of the sky, and he has a button which holds that system’s fire.

For three seconds at a time.

And that’s why I don’t fly interface vehicles.

– Svínif Kalyn-ith-Kalyn,
Sailing Master,
former Downrange Safety at Anniax Interplanetary, 6022-6167

Lowari-class pinnace/shuttle

Yes, that means it’s bad sketch time again here at the Eldraeverse… so here, have an interface vehicle.

LOWARI-CLASS PINNACE/SHUTTLE

Operated by: Various starports and near-orbit stations; capital ships.
Type: Pinnace / shuttle (belly-lander)
Construction: Llyn Standard Manufacturing, ICC & various licensees.

Atmosphere-capable: Yes.
Gravity well-capable: Yes.

Personnel: 3 nominal, as follows:

Flight Commander / Sailing Master
Flight Engineer
Purser / Cargomaster

(Can operate with a single pilot.)

Passenger capacity: 24.

Drive: 2 x Jetfire Technologies trimodal NTRs
Propellant: Hydrogen slush
Acceleration capacity (nominal load): 4.3 G
Delta-v reserve: 18,300 m/s

Drones: None.
Sensors: Standard navigational suite.
Weapons: None as standard. (Militarized version can mount turreted point-defense lasers above and below the bridge.)

Other Systems:

Auxiliary power reactor (thorium pebble-bed).
Navigational kinetic barrier system.
Regenerative life support (atmosphere only).
3 x Bright Shadow flight computer systems
Small vector-control core and associated technologies.
Integral radiative striping.

20150603_060009749_iOSAs can be seen from the picture, the Lowari-class is a very simple surface-to-orbit-and-back ship; flying-wing in form factor, with the entire habitable space occupying the center of the wing area, with fuel tanks outboard of that on each side, and the trimodal NTR engines on each wingtip. Flight control is primarily provided by thrust vectoring of the NTRs, but aerodynamic control surfaces and small attitude-control arcjets back this up.

The livable area exists on one single deck, which doesn’t include much in the way of dedicated machinery space; the machinery is squeezed into spaces behind access panels, primarily into the subdeck and behind the bulkheads of (in particular) the cargo hold. The largest of these are two dedicated avionics spaces (labeled AV) at the back of the cargo hold.

The for’ard half of the livable area is the passenger deck. As the ship’s not intended for long-term habitation, this means seats, not cabins;  large, comfortable, recline and put-your-feet up, quite-able-to-take-a-nap in leather seats with assorted luxury accessories, certainly – at least in the version they sell in Imperial markets, travelling like a gentlesoph and all that – but seats nonetheless. Three rows of four each to port and starboard; a total of 24 passengers.

This passenger area’s semi-divided by structures amidships. Going all the way floor to ceiling at the aft are two small compartments; a ‘fresher and what is, on the civilian model, a galley for serving drinks and snacks. (Military models may or may not keep this.) Ahead of that, and half-height, bearing in mind that the wing gets fatter towards the leading edge, is the airlock. It’s a fancy model with two operating modes: it has a conventional for’ard outer door designed to dock with other craft, but the floor also functions as an outer door; it’s designed to descend as a boarding ramp/boarding elevator when the Lowari is on the ground. (It can, of course, function as an actual airlock, even though the Lowari almost never does anything in space other than dock to/land in a bay of a larger craft.)

The flight deck is in the same compartment (indicated in green); it sits atop the airlock on a small platform of its own, where the three crew share one long console. It’s accessible by a long gallery leading to stairs on each side of the ship.

The leading edge of the Lowari‘s for’ard compartment, incidentally, is configured as one enormous picture window, because it’s not flying if you can’t enjoy the clouds on takeoff, the beautiful panoramas of space while in orbit, and the sheath of outrageously hot plasma trying to get in and incinerate you all on re-entry. Indulgent pilots may let well-behaved passengers come up and stand on adhere to the gallery to get a good view once they’re safely in orbit.

The aft compartment (accessible in-flight by doors to port and starboard) is the cargo bay, capable of housing eight or so standard cargo containers or an equivalent amount of breakbulk (including, say, the passengers’ effects). While said effects and suchlike are usually taken off via the bow airlock, there’s a large spacetight cargo door to aft/dorsal to allow large cargo to be loaded and unloaded. In space, this is often done by workpods, and the cargo bay is designed to depressurize for this purpose. (Conveniently, this also lets it serve as a backup airlock, if needed.)

Don’t go to space any other way!

Trimodal NTRs

Well, folks, it’s terrible sketch day again here at the Eldraeverse…
20150512_174156202_iOS

So, this is my approximate representation of what exactly one of those “trimodal NTRs” I keep talking about as the engine of choice for shuttles, lighters, and suchlike planetarily-landing craft looks like in cross-section. It is anything but a complete engineering diagram, especially inasmuch as the profile of the engine looks roughly cylindrical here, which of course it isn’t, especially on the inside; in actuality, it requires some pretty fancy variform properties in order to seamlessly switch internal profiles between those suited for a ducted-fan, for a ramjet, for a scramjet, and for a rocket – it being intended as a design that will function in all flight modes from the ground up to orbit – but I can’t properly represent those.

But it should give one an idea of what the major components are, with the possible exception of the cooling systems.

The core of the engine is the toroidal pebble-bed fission reactor that provides its power.

In its first mode, intended for low altitude, low speed flight modes, the reactor runs at low power, and while it does dump its waste heat into the airstream, it’s not used for thermal power. Instead, it generates electricity which is fed to the magnetic inductors, which in turn rotate the counter-rotating fans at each end of the engine. In this mode, the whole thing acts as a simple ducted-fan (usually a tilt-fan, for maneuverability).

In its second mode, once it’s got up to sufficient speed to make ram compression work, the flight control system feathers and locks the fans, shifts internal profile, and turns the reactor up to high (thermal) power. It then becomes a nuclear-thermal ramjet (yes, just like Project Pluto, although with better shielding), and the cascade vanes come into play for thrust vectoring. Once you’re going fast enough, continued internal profile shifts let it function as a nuclear-thermal scramjet, too.

And finally, once you start running out of atmosphere, the flight control system commands the iris valve to seal off the intake entirely, and the injection ports to open and squirt good old liquid hydrogen in there in place of the ram air, at which point it’s switched from being a nuclear-thermal ramjet to a nuclear-thermal rocket, suitable for use in circularizing at apoapsis and making your orbital rendezvous.

When you plan on landing planetside again, you run through the same three modes in essentially the opposite direction, with some pauses for aerobraking in between.

(Side note: it wasn’t actually intended at the time of design, but it seems to me that this also makes a pretty good representation of what’s inside those engine pods you see on the side of your Firefly-class transport ship

…Jetfire Technologies, ICC, warns that kicking anyone’s henchman into your engine intake will void the warranty.)