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[fic] Bus Driver
RE: [fic] Bus Driver
#10
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Nobody likes being told they’re shit. Nobody likes being reminded that they’re not the hero they think they are.

The problem with the wave, is that it makes everyone feel like a hero.

You want to be a Top Gun? A little bit of a handwave, and you’re merrily flying away in your Valkyrie fighter, cushioned from the reality of your ham hands and clubbed feet by some of the most powerful computer systems fitted to any spacecraft.

These fly-by-wire systems sit between you and the spacecraft, filtering your commands out into things that the spacecraft can actually do. You go full back stick, and instead of commanding the control surfaces to move as far as they can like you want, the computers work out how far they can be safely moved without breaking the limits on the spacecraft and give you that instead.

You can do catastrophically dumb things in it, and it’ll never spin, depart, or snap back at you. You can’t break it, no matter what you try do. You might still manage to kill yourself if you fly straight into a rock, or do something dumb in front of an enemy’s guns, but we try to train you to avoid that.

The point is, the skill floor is so much lower.

Anyone can fly one well enough to be effective and not die.

You’re the hero. And the more skilled you get, the more of a hero you become

Now, once you have the computers in there, you can do some utterly insane things with spacecframe design. You can build something so hideously dynamically unstable that no human could ever hope to keep it under control. Ever try and fly a Talon with the FBW system disengaged?

I managed to keep it under control.

For about half a second before it snatched and shattered itself.  

All these modern fighters are basically the same. You’re giving ideas to the computer and it’s turning them into reality – the only drawback being that maybe, these systems will prevent you from exceeding those limits on that one occasion where you might really need to

The Sleds take it to the next level, being fitted with an actual, physical intellect capable of recognising the incipient ‘Oh Shit’ moment and either saving your sorry ass from it or realising you’re trying to save your sorry ass and letting you do it – even if you bend the jet a bit in the process.

Hell, with the sleds, we used to trim it with the CoG so far aft they became dynamically unstable, just to pitch it into an evasive turn that little bit faster. Something that destroyed a real SR-71 fifty years ago gave us just that little bit of an edge when we needed it – and made for one or two black bananas in the process which never flew straight again.

Flying by wire is like flying on rails. Point and go.

So.

Cut to the Foxhounds.

Which by design take completely the opposite philosophy.

It’s all up to you.

Let me say that again.

When you sit in that seat, it’s all up to you. The ship’ll try do exactly what you tell her to do. Whether it can or not.

Pull the stick too far back, and you’ve either an accelerated stall, or a buckled airframe.  Even a gentle roll is rewarded with a wandering nose and some adverse yaw – especially at landing speeds. Shoot a missile off a wing with just a bit too much bank on and it can snap into a roll. Overspeed the engines and it’ll start to overrun its own fuel pump’s ability to limit flow, leading to a frightening rocket-ride until either the engines destroy themselves, or you force an unstart. It will stall at low speeds and sabre-dance or augur in with the best of them. At speeds above .18 it’s reached the limit of it’s pitch trim and you’re holding it back manually to keep it from tucking in.

The point is – unlike maybe ninety percent of ships in Fenspace, the final authority is in your hands, pilot. All it’ll ever do is warn you that you’re about to break the limits. The controls either get heavy, or start to float – sometimes you feel it nudge a suggestion if you’re gonna get in real trouble but it never stops you doing what you want to do.

For better or worse.

On the one hand you get a great feel for what the ship is doing – you learn to read it well enough.  It never feels threatening. It’s enough to humble you as a pilot by revealing the limits of your skill. It’s enough to teach you how to start to become a better pilot by showing you the things the automated ships hide.

On the other – well – sometimes you can get surprised…. Especially if you’re not used to ships that can bite back.

The first squadron is given the people who actually know what they’re flying. We’re people who might’ve had real flight experience before coming up. A few ATPL’s or a few PPL’s with four-figure hours in their logbooks.

People who could understand why the Grey Lady’s behaved like they did with it rather than just gawk at ‘What the spaceship just did’ as it spiralled to the ground around them

The second squadron is transitioning from Veritechs and they’re all convinced they’re the hottest shit since Chuck Yeager.

Boy are they about to get brought down to earth. Hopefully without breaking the ship in the process…

All is going well at first, and we’ve a squadron of hotshots eager to get their hands on what is arguably* the fastest combat spacecraft in existence. Ground school and the training cycle sit in and we have to go back to some flight basics.

You’d be surprised at how many supposedly intelligent people are surprised that the fifty-ton lump of welded battlesteel bigger than most faction’s cruisers isn’t going to steer quite as quickly as their titanium veritech.

Anyway, we manage to score some proper earthside training time by renting a field in Nevada, pay a courtesy call to Beale to give a particularly noteworthy rider a chance to fly in the Sled’s great rival, and give our nuggets their first taste of true wing-and-air wave-free airmanship in a couple of flight-school 172’s older than they were.

Most importantly, they learn how to stall and recover a plane. And what causes an aircraft to stall.  The Cessna’s are docile enough that if you do absolutely nothing they’ll recover themselves, even from a full power, full-flap spin.

We spend a lot of money to rent an L-39 from a local flight training school. So yeah, this is what a real jet feels like in real atmosphere. We also get some practice in for some of the maneuvers we’ll get the Foxhounds to pull on the display line.

Including controlled stalls. Which is little more than a fall with style, where the airspeed is so slow the wing cannot produce enough lift to keep the plane in the air, so the whole ship just sort of mushes towards the ground

Now, the basics you need to understand is that it’s not the air speed across the wing that causes it to stall, it’s the angle of attack – alpha - against the air. The basic rule of wings is that, the more alpha you have, the more lift you get – up to a point. When the alpha gets too great, the airflow at the back of the wing detaches, the high pressure from beneath the wing flows back up over and you’ve suddenly got a big nasty load of turbulence, a lot of vibration in the airframe  and a whole lot less lift than you had a second ago.

The slower you fly, the higher an angle of attack you need to make enough lift to stay in flight – eventually you go too slow, the alpha gets too high, and the wing finally stalls. To save the airplane, all you need to do is lower the alpha – by either accelerating or lowering the nose.

Or preferably doing both.

This also works the other way around. Even at full throttle, high speed – once you reach that alpha limit – if you’re yanking and cranking at high G - the wing will stall.  That’s called an accelerated stall, which can be surprising if you’re not used to flying a ship that’ll do it.

The other thing you need to know is, sustaining a flight at really high angles of attack means that some of the wing’s lift vector is actually holding you back – you’ve so much more lift induced drag you need a lot more engine power to keep flying forward. We call it the Back side of the power curve – or the area of reversed control, where things start getting a little bit counterintuitive. Pulling up can cause you to sink.

As an exercise, it’s a great way of demonstrating how the ship behaves at the edge and how easy it is to get away from it. Both stabilitors mean you can hold it steady even when the ailerons loose their authority.  As a show manoeuvre, it’s thrilling for the spectator because they think they’re about to see an accident, right up until you save it by lowering the nose, trading some of your remaining altitude for speed and slamming the throttle. It has just the right appearance of danger and thrilling fire and noise to be a hit, with plenty in reserve to keep it safe.

Do it right and you never actually stall, as the alpha is always in limit.

So. Last flight of the day. I’m up in a two ship formation with one of the hotshots. Chatterbox is running the radios to get us a block of altitude to play around in while I’m giving instruction.

It’s myself in Foxhound 1-1, and our Hotshot who’ll remain namless in 1-2. Tail-number 024.

We both start bring down the power, easing back on the stick to slow down. So far so good.

We’re both nose up, tail down and steadily, we ease up on the stick just to keep alpha in limit. Almost level with the horizon, low enough to avoid a full aerodynamic stall. Both ships start to drop, not having enough lift to fly. A little bit of care with the throttle and we can hold it right there on the limit. Alpha’s okay.

Now, this is a fairly easy thing to do in a fly-by-wire electro-jet. The computers will never let you go through the alpha limit. In the Foxhound, you can feel the point where the airflow begins to separate – it makes the ailerons go light and you get a god-awful vibration up through the frame.

Just enough to warn you to stop it and balance it on that point with stick and throttle.  

Still, so far so good.

Now, time to lower the nose and power out. I give the instruction, releasing the pressure on the stick to let the nose fall below the horizon on my own ship before jamming the throttles to full. There’s a stomach in mouth moment with the negative G, but she grabs the air in moments.

024 just hangs there in the sky.

024 blasts up to full burner, pitching the nose even higher.

He’s got that thing so far off the back side of the power curve – further than we’d ever calculated possible - full burn is just about enough to keep it airborne through a triumph of raw thrust over physics. He’s got the nose aimed straight up at the sky and both engines screaming. The stabilitors are twitching like a turkey’s feathers trying to keep the stalled wings level.  

I’m yelling at him to just drop the nose and let it fly out of it, but he’s panicking. He’s surrounded by alarms, flickering warning lights and a ship that’s physically shaking itself apart screaming at him to stop and he freezes.

Instinct wins over and he just holds it full back to go Up!

Eventually, one of the engines surges, then the other. Both throttles retard to catch the surge, dropping the speed below that critical point where even the stabilitors can hold it. Gravity wins. The right wing lets go first and all fifty tons of ship just snap like one of the strings holding in the air had finally just broken.  

It corkscrews over onto its back, engines still driving it over into a full power-on spin. It screws itself through three revolutions in half as many seconds like a broken bottle rocket before orienting itself vertically nose down.

Still under full power.

Still spinning.

Still under full afterburner as the engines recover.

We’re calling in a mayday because there’s no way anyone aboard is even conscious and we’re sure we’re just calling in a cleanup crew for the inevitable mess. I’m thinking off the bad letters I’m going to have to write and the inevitable investigation and ramifications for interplanetary relations.

Meanwhile, 024 does something remarkable. It stabilises. All on its own. Score one for positive stability.  

It’s still going down like a dart, but it’s stopped spinning.

I’m holding altitude, watching the ship scream towards the earth. It’s already gone right through the sound barrier. I’m just watching for a chute – either the pilot or the ISO because there’s no way anyone’s recovering that thing.

Slowly, its contrail begins to curve, arcing away from the ground.

024 levels out at something like a thousand meters. 024 continues to pitch up into zoom climb, coming up like something NASA built.

She levels out at ten kilometres, trailing fuel vapour from a broken tank. A panting voice crackles over the radio.

“Uh…Foxhound 1-2. I’m stable. I have damage. Lost hydraulic pressure…uh….declaring an emergency,”

I remember thinking, That’s the sound of someone who just gave birth to last night’s dinner in their g-suit.

Both of us make it to the ground in one piece, despite the bits visibly hanging off 024.

Naturally I’m chewing his dumb ass out more out of relief than anger. Our earthside flying is at an end and we’ve got a report to fill out for the FAA explaining exactly what dumb thing we did.

The Hapless hotshot had been knocked-out by the first snap. He came around halfway down, and pulled hard back on the stick in a panic with a window full of Nevada ahead of him and the machmeter going through 1.8. Then blacked out again as the ship came through horizontal resulting in a zoom-climb with the helpless ISO screaming at him in the back seat until he finally woke up at 10,000 and stabilised.

The cockpit G-meter had pegged at 8 during the pullout. The flight recorder recorded 13. The Foxhound was rated to 5.

One of our mechanics checks the ship out, and it’s immediately clear she’s an expensive write-off.

The entire frame is warped so out of line it refuses to trim straight. Her wings are bent up nearly 6 inches at the tip. One of the rudders and both ailerons are gone – dropped somewhere over Nevada. Two of three hydraulic circuits are empty. The gear doors are missing and both engines have had their mounts cracked. Three of the fuel tanks are leaking where the seams split. One of the engine casings even shows marks from where the turbine blades hit it as the frame bent.

Anyway, the usual investigation follows. Interview boards. Briefing boards. A mountain of paperwork.

The FAA calls it pilot error.

We have some training questions to ask.

And the usual debate continues. If the ship’d had a fly by wire system, it might never have allowed it to try that 13 g pullout. It’d have pegged at 5G to save the airframe and we’d be dealing with a fatal accident. To which the ‘bus drivers naturally say a fly-by-wire would never have allowed it to get into that situation – which then ding-dongs back to the fact that FBW systems like to go into alternate law mode when they see anything they don’t understand – putting control back into the hands of a pilot who just doesn’t realise it’s back in their hands.

I’ll leave the control debate up to you. The lack of a fly by wire computer probably caused the accident. The lack of a true fly by wire probably saved the ship.

The fact that the ship was made out of welded steel and took a sustained 100% over-g probably had something to do with it too.

But if it was up to me, I’d make sure all the hotshots got a chance to fly something humbling – if only to remind them of what all that automation is doing on their behalf. Before all the skills we used to have get washed away by the wave and forgotten.

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*arguably. Based on definition of ‘combat spacecraft’, how long it can sustain that speed, what load it can carry while doing so, whether it’s a prototype or something ‘produced’, what counts as ‘produced’, how fast it’ll go in an atmosphere, acceleration rate. and the phase of the moon. It’s a tossup with the Fearless, the Talons, the Blackbirds, The Firefox, and the Foxhounds and you’ll find a dozen arguments for each, and each will be equally valid which results in some truly glorious flame wars on certain boards.

I love the smell of rotaries in the morning. You know one time, I got to work early, before the rush hour. I walked through the empty carpark, I didn't see one bloody Prius or Golf. And that smell, you know that gasoline smell, the whole carpark, smelled like.... ....speed.

One day they're going to ban them.
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Messages In This Thread
[fic] Bus Driver - by Dartz - 04-03-2017, 01:29 AM
RE: [fic] Bus Driver - by Dartz - 09-10-2017, 01:29 PM
RE: [fic] Bus Driver - by Dartz - 09-24-2017, 02:02 PM
RE: [fic] Bus Driver - by robkelk - 09-24-2017, 06:56 PM
RE: [fic] Bus Driver - by Star Ranger4 - 09-24-2017, 11:35 PM
RE: [fic] Bus Driver - by Dartz - 09-25-2017, 12:46 PM
RE: [fic] Bus Driver - by Dartz - 10-01-2017, 05:45 PM
RE: [fic] Bus Driver - by Star Ranger4 - 10-02-2017, 10:57 AM
RE: [fic] Bus Driver - by Dartz - 02-10-2018, 08:21 PM
[No subject] - by Black Aeronaut - 04-03-2017, 07:45 AM
[No subject] - by Dartz - 04-03-2017, 09:27 PM
[No subject] - by Star Ranger4 - 04-05-2017, 01:55 AM
[No subject] - by Dartz - 04-05-2017, 10:42 PM
[No subject] - by Black Aeronaut - 04-06-2017, 10:41 AM
[No subject] - by Dartz - 04-10-2017, 12:37 AM
[No subject] - by Black Aeronaut - 04-10-2017, 10:10 AM
[No subject] - by Dartz - 04-12-2017, 12:48 AM

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