"This is a stupid exercise."

"Yeah, well, if you weren't such a shitty pilot, maybe it wouldn't be."

Airspace above and around Tracy Island is an internationally recognized no-fly zone, within a hemispherical radius of a solid hundred miles. This is something their dad worked incredibly hard to finagle, and it ensures the island's safety and privacy, as well as guarantees a space for the Thunderbirds to be put through their paces, as is occasionally required for testing and training.

It's the latter purpose that has Scott lingering at the upper border of the stratosphere, flirting with TB1's altitude limit and cruising lazily around on autopilot. Today he's the trainer rather than the trainee, and the afternoon's endeavour is a combination of two of the things John's worst at in the entire world: flying and the gracious acceptance of valid criticism.

The training in question is meant to take place in the midst of a mobile aerial course, designed by Brains, and made up of a suite of drones of assorted shapes and sizes. These can be remotely configured to represent various situations, and are meant to iterate upward through a series of complex levels, designed to test and train a pilot's skills. Scott knows them inside and out, backwards and forwards, and can run courses designed for TB1 and for him flying solo with his jetpack, practically with his eyes closed. Flying Thunderbird Shadow, at least twice as aerobatic as any of the rest of the 'birds, Kayo can do it with her eyes closed, because TBS can essentially take the course on autopilot. Beyond that, Scott regularly puts Alan and Gordon relentlessly through their paces, usually with the pair of them flying Pods A and B in tandem, laughing and whooping and relishing the challenge. Occasionally even Virgil will take TB2 through a modified version of the course, piloting the biggest of the Thunderbirds as though it's a machine only half its considerable size.

Before now, John hasn't had anything with which to fly the same course. But his Exosuit is meant to be a versatile piece of equipment, meant to be equally useful both in and out of the atmosphere. And while it was in development, John had dutifully gotten plenty of virtual experience, and once it was completed, he'd even logged a passable amount of time in zero-G, just jetting around in orbit, getting accustomed to the suit and its controls. But he's only flown it once or twice, in atmo, with gravity. And as far as Scott's concerned, that just won't do.

So, training. A requisite minimum of a hundred flight hours, with Scott around for instruction and supervision. They're about eight hours in. It could be going better.

His younger brother is taking a breather, perched on the small deck of one of the drones, with his wingspan folded and his long legs dangling over the edge of the platform. All Scott had done was clear his throat over the open radio channel, marking the end of what he'd considered to be a generous three minute break, and suggested that maybe John might want to get the next exercise started, with daylight beginning to fade from the South Pacific sky. And John had gotten snappish. And, losing patience with his brother, Scott had snapped right back.

Admittedly, Scott's maybe not the softest touch or the best teacher in the world, and maybe he's crossed a line, because there's a frosty silence over the comm. And then—

"I am not," John answers, and Scott could swear that the temperature inside his helmet actually drops a few degrees, "a shitty pilot."

By Scott's standards this isn't true, but then, Scott's standards are high enough to flirt with the upper border of the stratosphere. John can fly. John flies reasonably well. He could probably fly better. Still, Scott modulates his tone, though he needs to be very careful not to patronize his younger brother. "Well, okay, maybe that's a little too harsh a term—but you have to admit, objectively, you are the worst pilot in the family. You've got the least experience out of the five of us. The six of us, if you include Kayo."

"Objectively, you can blow it out your ass, Scott."

The bad attitude is uncharacteristic, but then, they've been at this for hours now, and John gets frustrated when his efforts don't result in tangible progress, and can't seem to help taking criticism personally. Scott's been pushing him pretty hard, finding something to correct with every attempt at every exercise. And he sighs, tries to remember the last time he had to deal with one of his brothers pitching a tantrum, thirty miles above sea level. Probably not since the last time he'd made Gordon and Alan race through the course, and Gordon had won on a technicality. "Buddy, you're the one who wanted the Exosuit. Our tech has a learning curve, you know that. Just because you haven't had to learn the ropes of a new piece of gear in a while doesn't mean you're suddenly exempt from putting in the damn work."

"This is still a stupid exercise. I know how to fly my exosuit."

"No, this is a necessary exercise. When you first got the damn thing, you didn't even know which button to hit."

"Shut up. My time is a lot more valuable than this."

"Your time is only as valuable as the skillset that backs it up, and thus any time you spend training is necessarily time of value. And I think we both know that you could do to spend a bit more time training."

"I spend plenty of time training!"

"Not in a non-virtual space, you don't."

"My sims are—"

"Not a patch on the real thing, and anyway they're all coded for zero-G. You need proper training, and this is how we train in atmo."

"You don't know the first damn thing about my sims. And why the hell do we even have simulations, if they don't actually count?"

"They're fine for learning the theory. But they're academic, they're not experience."

"Three hundred hours of sim time—"

"—is not the same as logging actual goddamn flight hours, John!"

"Yeah, well—"

"Boys."

Their grandmother's voice slices the channel in half, leaves the raggedy edges of static behind in its wake. Her sternness and moreover, her disappointment are enough to shut the both of them up, pretty much immediately. The abashed quality of the silence indicates that they're both deeply ashamed to have been caught arguing. Grandma Tracy allows a few judgmental seconds to pass before she clears her throat, and continues, "We've got a medical distress call, a private cargo flight out of Auckland headed for Brisbane. The plane is in flight over the middle of the Coral Sea. Pilot is experiencing chest pains and shortness of breath, has no copilot, no other passengers or flight crew aboard. He's requesting immediate assistance."

Scott's never exactly glad when a rescue crops up, but in this case it's a welcome break from a stupid fight with his brother. And halfway between Auckland and Brisbane is the bit of the South Pacific that represents the equivalent of their backyard, at least as the Thunderbird flies. "FAB, Tracy Island. Thunderbird One responding," he answers crisply, and even at distance, he can see that John's already pulled himself back to his feet aboard the drone, reengaged his controls, and is about to hop off the platform. "Stay put, Thunderbird Five, I'll fly by and pick you up."

"Negative, Scott, don't waste the time. We're only fifteen klicks out, I can get back to the island on my own. Tracy Island, get me a line to EOS and TB5, I want to start running intel on this vessel and its status—"

Scott's already pulled up alongside the floating platform, thumbed the switch to open his cargo bay. "Cancel, Tracy Island, have Gordon tag in to stay on the line with the pilot, forward us stats as relevant. John's flying with me, I could use an extra set of hands. Time for some on the job training."

There's a brief silence from Tracy Island, as though Grandma Tracy is evaluating the probability that her boys will behave, with both their tempers already running high, and their patience running short with each other. "Thunderbird Five, confirm?"

There's the very barest pause over the comm channel and then a terse, "FAB."

Learning by doing is something Scott's always believed in. There's a hydraulic whine at his back as the cargo bay slides open, and then a throaty little burst of rocket fuel, as his brother arrives on board. As the cargo hatch closes, Scott calls over his shoulder. "Welcome aboard, Johnny. Pull up a seat."

All he gets in answer is a faint grunt, as John's exosuit powers down, the weight of it no longer self-supporting as the propulsion systems turn off. "You do realize I can't actually get out of this thing?" he asks, as Scott starts to prepare to go to full throttle, checking and rechecking the telemetry as provided by Tracy Island.

"Well, I don't know why you'd want to, you're just gonna need to get right back into it. And on that note, you're gonna wanna brace yourself," Scott answers cheerfully, and jerks a thumb over his shoulder, vaguely in the direction of a couple anchor points at his back, "Our ETA is about six minutes. Get your sitrep from Gordon on the way."