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Comment by antsar | Hacker News Reader

(not a pilot) I'd think causing the autopilot to believe it is substantially off-course would induce a sharp bank to correct course. That bank at low altitude can lead to a wing strike. If not, still seems plausible to deviate enough to impact obstacles near the runway.

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No airplane low enough to have a 'wing strike' due to a bank would be on autopilot.
In any other condition, the pilot would see the runway well before the aircraft was at an altitude low enough to touch the ground in any sort of bank or turn.

A commercial airplane operating under Cat IIIa ILS at a Cat IIIa Airport could operate on autoland to the touchdown point

Possibly? Not a pilot either (but I took multiple human factors courses which talk a lot about air crashes).

I'd hope that the pilot would notice something is off and abort the landing before that. (Eg: visually be like "oh there is something on the runway I thought I was cleared on)

Theoretically even if cleared for landing they should keep an eye out and abort if, say, an errant baggage cart was in the way.

(Am IR pilot) Assuming someone is paying any attention, the autopilot suddenly nosing down and the vertical speed increasing would immediately result in missed approach procedures being executed. These approaches usually terminate at a pre-determined height (decision height) which unless you're flying CAT-IIIC (not really used) is minimum around 50ft and more commonly between 100 and 200ft. Therefore you have some room for error in the event something bad happens. Additionally, approach paths won't have any protruding objects within a certain range of the runway.

Former commercial pilot here: we user to be doing IIIC approaches at least 3 times a year.

For the rest, usually below 10.000 feet, there van never be "two heads up", so one pilot is always watching the instruments. Any deviation from expected parameters (airspeed, verticale speed, ils deviation, radio altitude) Will result in an unstabilised approach and thus the execution of missed approach procedures (a go-around).

As mentioned elsewhere, everyone in aviation knows these systems are as insecure as can be.

Edit: forgot to finish a sentence..

Interesting, didn't realize IIIC was widespread just yet. Is it being used down to zero/zero or are the published minimums higher typically?

We had to do 3 supervised IIIc approaches all the way. Other than for training purposes I never had to use IT ;)

Pilots aren't always that eagle-eyed, and it is of course much more difficult at night. The very close call of the Air Canada jet that nearly landed on four or five other jets waiting on the taxiway at SFO is a testament to just how badly this can go. And an attack that leads the aircraft into terrain or buildings could put the aircraft into a local minimum that it can't fly out of.

Frankly aviation is ripe for cyber attack. The problem is not simple to solve, mainly because introducing crypto into critical navigation systems will also introduce failures where legitimate service is interrupted due to system glitches. It will take crashing a jet before the industry decides to take this seriously, and it is entirely possible that a terrorist group or state actor will use this weakness. Government and industry can and would respond, but it would take money and time.

>Pilots aren't always that eagle-eyed, and it is of course much more difficult at night.

I would not place blame with a pilot who is cleared for landing, and fails to see something on the runway. Even if they are making a good faith effort to scan the runway, it's hard to see things from the sky with your eyes.

>It will take crashing a jet before the industry decides to take this seriously, and it is entirely possible that a terrorist group or state actor will use this weakness.

I agree it's an issue that should be worked on, but I think it's much more likely (as a parent pointed out) someone will simply fly a drone into the airspace.

After all, bird strike incidents are a major cause of crashes:

>The Federal Aviation Administration (FAA) estimates bird strikes cost US aviation 400 million dollars annually and have resulted in over 200 worldwide deaths since 1988.[56] In the United Kingdom, the Central Science Laboratory estimates[8] that worldwide, the cost of birdstrikes to airlines is around US$1.2 billion annually. This cost includes direct repair cost and lost revenue opportunities while the damaged aircraft is out of service. Estimating that 80% of bird strikes are unreported, there were 4,300 bird strikes listed by the United States Air Force and 5,900 by US civil aircraft in 2003.

https://en.wikipedia.org/wiki/Bird_strike

Birds do most of the work to avoid bird strikes, and are avoiding airplanes daily. The same can't be said for terrorists.

Wouldn't you yaw with rudder and asymmetric engine power when at low speed at a lower altitude, instead of using a bank turn?

If you could potentially cause a wing strike, why wouldn't you just trick the plane into landing on the taxiway, for maximum chaos?

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