Conceptually, you could look at it from a first-principles individualist perspective:  Almost everyone who rents land, even somebody who purchases a house in the distant woods with solar panels to run an automated hydroponics setup for vegetables and shrimp, would conceptually like to also rent a right over the surrounding ten kilometers of airspace which says, "I do not want enormous masses of metal and high-energy fuel going through this air near my house, unless a prediction market says with extremely high confidence that it won't crash on me."  If it was only one individual who thought that way, those air-rights might be pretty expensive to rent; but just about everyone thinks that way, so everyone on the planet can conceptually club up and rent the overlapping air-rights for kilometers around their houses.

Accordingly, you cannot just go to the Ill-Advised Consumer Goods Store, and buy an Ill-Advised Airplane that you can go fly yourself, because something like that doesn't just endanger yourself like buying a few kilograms of heroin.  All the cubic kilometers of air around you have had their air-rights rented from Civilization to say, "No amateur flyers here."

Or think of it from the perspective of a coastal city, looking out at kilometers and kilometers of ocean, wondering if some rogue aircraft was going to zip out and crash into a skyscraper.  It's not enough to say that it's legal to fly around however you like outside the city borders, but illegal to crash a plane into a skyscraper; because, if somebody does crash into a skyscraper, saying "That was illegal!" and fining them doesn't properly compensate for being true-dead.  A city would like the law to be such that you can't bring a plane close to the city, even across kilometers of ocean, unless it's insured against crashing into skyscrapers at really quite a very high disaster-price.

If there was only one city that wanted rules like that, maybe it'd have to buy its own radar equipment and surface-to-air missiles and put up its own surveillance satellite.  If there was only one city like that, it would be very expensive to live in a city which could guarantee you against planes crashing into your skyscraper.  But actually most cities, nearly all cities really, have a preference like that.  They'd like to club up and pay Governance to just keep uninsured aircraft out of all the land and all the ocean.

There's a region, Crashland, where mad inventors go to fly untested aircraft--logically, this is how any aircraft ends up 'tested' in the first place--but even Crashland is owned by a governing-city-state-corporation that laid the building-foundations to be rented, and contracted for an overhead airspace with exceptional rules, so it could resell space to mad inventors.  Crashland's regional authority has an interest in being able to sell testing-rights on a schedule where you know your aircraft, or your house, won't be wantonly crashed-into by another untested aircraft.

Unusually scrupulous, conscientious, nitpicky, obsessively rigorous dath ilani who identify as "Chaotic" sometimes worry about this state of affairs, and object to it as having ended up in a de-facto state of rigid inescapable tyranny:  Almost the whole planet ended up with one insurance requirement and insurance-requiring regime that's very difficult in practice to evade!

Ordinary dath ilani would mostly roll their eyes about that, though.  If you were going to complain about that for air travel, why not complain about it for the nuclear reactor insurance regime, since sufficiently bad nuclear meltdowns could raise background radioactivity around the whole planet?  Why not complain about the uniform regime over biotechnology labs?

There's an actual per-capita annual payment that gets made to planetary Governance for the air-rights on the planet, the same way as any other land-rights get rented by the collective population.  It's cheap, because nobody is putting counterbids on those rights.  In principle, some special interest group or faction could place an opposing bid if they wanted air-rights to work differently, and try to outbid everyone else, if that faction cared more than the rest of the planet collectively did.  No such faction has outbid the rest of Civilization on global air-rights.  You'd have to be pretty Chaotic to object to that sort of outcome--the sort of unsatisfiable-complainer who whines when a majority of the planetary population wins a bid on any collective feature of reality that can't go both ways.

Which is to say:

Every single aircraft on dath ilan, inside or outside of Crashland, is there on a schedule and a sublicensed right of passage.

It has a radio transponder that identifies its location to the planetary satellite network.  A tamper-proof one.  The guarantors who'd be on the hook for an insane amount of money if an airplane crashed into a skyscraper have put some effort into making that transponder hard to take off your plane and stick onto a rocket that flies off in a misleading direction.

If that transponder fails, you need to not get near any high-density residential areas or nuclear power plants.  A big city or nuclear plant might actually have surface-to-air missiles.  Like, they wouldn't tell you, it's not public knowledge, but probably there are surface-to-air missiles guarding all the really attractive targets for spoilers; operated by Law-Abiding Sociopaths who will shoot down a plane carrying 175 souls if that's what the cold equations say to do.

A regularly scheduled airplane flight is far over the water heading towards the Default Continent when several red lights go on in the cockpit simultaneously, accompanied by a chirp that means "look at the instrument panel, the plane isn't about to crash but at least one of those messages is important".

The Captain (personal name Pambar, but nobody who works on an airplane, with new passengers constantly boarding and departing, is going to make anybody remember their name) immediately looks at the brightest light.

"Exception!  Transponder failure!  And--satellite positioning failure, satellite comms failure, satellite Network access failure--we have lost all satellite systems simultaneously."

Oh, that's not good.  Satellite frequencies are 1.5GHz for the global positioning system, their transponder lock runs on 3.5GHz, and Network access is 70GHz.  They're not in the middle of a thunderstorm, just over clouds, there's no thunderstorm scheduled to be near them, there's no solar weather warnings, and the X-Ray/UV component of a sudden solar flare and subsequent ionospheric disturbance shouldn't wipe all of those bands simultaneously.  GPS and transponder systems are located at the head of the plane, Network access is in the rear.

That implies (1) the problem is on their plane, and spread across a wide volume of it; or (2) there was a problem with a lot of satellites simultaneously; or (3) something non-obvious is going on.  None of those possibilities are particularly fun.

That's one track of the First Officer's mind; the other is checking that the first emergency backup radio beacon has automatically switched on (it has) and broadcast that an exception is in progress, now five seconds old.  He flips the "Return to your seats nonurgently" light for the rest of the passengers on board the aircraft, which creates some optionality in case anything else is about to go wrong; leaving the reason blank will create some worry about what the pilots have to do that's more important than explaining the seat-return light, but it's not like that worry is unjustified, and the absence of an explanation for the Network outage will also be conspicuous.

Once he's done that he turns to look at the Captain.  "First-order-belief-formed about what we do next."  You form that opinion yourself before the other person speaks, to prevent opinion cascades.

"My memory doesn't have anything we do for this combination that we don't do for any other form of cockpit comms failure.  You turn on the shortwave emergency radio, I'll check all the instrument panels for anomalies."

"Arguendo:  Anything which just damaged all active comms might damage the shortwave radio if we naively switch it on right away."

"Not seeing any signs of other damage to onboard electronics on the panels."

"Arguendo:  Could wait 5 minutes to give an unknown comms-equipment-damaging phenomenon to potentially subside."

"Negative, if there's extraordinary circumstances not local to this airplane then land may have urgent instructions on emergency frequencies.  We can use the backup emergency radio if there's an ongoing damage source applying only to turned-on equipment."

He doesn't actually think aliens just wiped their satellite network... but there could be some other weird thing going on that's not local to the plane, sure.  He doesn't actually know what's supposed to cause simultaneous failure of all of those radio frequencies.  He reaches out to the shortwave radio switch, then pauses.  "Predict 2:1 that 14.3Mhz is unobstructed."

"I'm at 1:1.  Bet my 40 if it works vs your 60 if it fails."  It's not particularly about money or pride, in this case, it's about which of them is forming a better grasp of the general emergency.

"Ack."

He flips the switch that turns on the shortwave radio.

Shortwave radio cannot ultimately be reliable in the sense of 99.999% uptime.  Immediate, unannounced impacts of solar flares actually will knock it out.  So long as everything is working correctly, satellite communications are more reliable than shortwave.

What shortwave radio is, is simple.  Radio in the 3-30MHz range will bounce around between the ionosphere and the land, potentially for thousands of kilometers.  Shortwave does not require locking onto a satellite, nor frequency clocks that run at exactly 70.231 GHz.

You can, if you know what you're doing, build your own shortwave radio in a cave out of a box of scraps.

A shortwave radio in dath ilan is therefore built for exactly one purpose:  Exception handling.  A shortwave radio is a failover for when something less simple breaks.

And in dath ilan, when code crashes due to an unhandled exception inside an exception handler, the resulting code dump includes a standard message saying the programmer needs to be fired.  Shortwave radios are built to work very simply, for when somebody tries to use them during what's at least an exception and possibly some sort of very distracting emergency.

Shortwave radio bands in dath ilan are kept clear, except for regularly spaced audible ticks broadcast all around the planet, whose spacing tells you what frequency you're on and that your shortwave radio is working correctly.

Shortwave radios don't use clever computer-compressed transmission protocols.  That would require an inscrutable computer chip, instead of a circuit board all of whose connections you could potentially check by hand using a multimeter.  The standard protocol directly transduces voices to amplitude modulations, in a way you could send or receive in the aforementioned cave using your box of scraps.

There is often a computer chip on board a shortwave radio, if it's fancy expensive emergency equipment.  But it's not a required chip--you could yank the chip out of the circuit board if you decided you were suspicious of it, and the radio would still work.  The chip is designed not to have the physical capability to send outputs that prevent the radio from working.  What the chip does do is gently diagnose every part of the system using secondary wires; for regular self-tests, or to light a red indicator light if you've had the incredible bad luck to lose ordinary satellite comms during a solar flare.

"We have a green light on the shortwave.  I am not hearing any ticks."  He doesn't add, 'that's not good', because this would convey no additional information.

"First-order-belief-formed about next-actions."

"I have:  Bring in additional flight crew member in case we are somehow both missing something very obvious.  You check our backup papers for the timing of a switch to backup flight route and prepare to fly that route based on inertial guidance.  I go public."

"Same."  He gets out of his chair and goes to the cabinet with the spiral notebooks full of auxiliary info.

Their previously planned route will take them way too close to populated cities for this to be in any sense okay for an airplane that has lost all comms to do.  So before the plane set out, as a matter of routine, Air Traffic Control printed backup routes the flight could shift to in case of an exception that caused them to seem unsafe; a route that would take them to a failover emergency landing field on a flight path that did not scare any skittish major cities or nuclear power plants.

The airplane will turn into that alternate corridor at a predictable exact clock time, based on a broad time window for when the emergency started; such that anyone who knew roughly when the airplane transponder failed would be able to predict exactly when they'd turn into the alternate corridor and exactly where they'd be, even without using satellite surveillance info.

She flips on the flight-crew-only intercom.  "Steward to cockpit, urgency 7."

An otherwise unoccupied steward will head over to the airlock system granting access to the cockpit.

The Captain pokes the First Officer to be attentive and ready to act, and then checks over the steward in the airlock over more carefully than usual through the peepholes.  They are very confused right now, possibly some Sophisticated Criminal is fucking with them, and maybe this guy is about to try to steal control of the aircraft.

"What's up?"

She gives him an abbreviated report of events, containing no inferences or explanations whatsoever, just what they observed, what they did, what they observed.

"Do solar flares do that?"

"According to me, the zero-warning first front of a solar flare does not block all of those radio frequencies simultaneously.  Furthermore if noise is blocking transmissions, the primary radios should show that in indicator lights and it should be directly audible as noise on the shortwave."

"I've got no mundane explanations.  Obvious non-mundane explanation, the criminal conspiracy hiding in the shadows of Civilization finally made their move and they simultaneously took out the satellites and the shortwave emergency stations as part of their opening play."