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299 points cjr | 29 comments | | HN request time: 0.996s | source | bottom
1. comrade1234 ◴[] No.44537976[source]
Why can the pilot shut off the fuel during takeoff?
replies(5): >>44538051 #>>44538072 #>>44538078 #>>44538334 #>>44539761 #
2. jeffbee ◴[] No.44538051[source]
Suggest a system that would prevent this, but only this, without causing other risks.
replies(3): >>44538226 #>>44538263 #>>44539579 #
3. baseballdork ◴[] No.44538072[source]
Fire, probably. But also, how complicated would you make the system if you needed to prevent certain switches from working during certain times of flight? At some point... we're all just in the hands of the people in the cockpit.
replies(1): >>44538393 #
4. rhcom2 ◴[] No.44538078[source]
Completely uneducated guess but if one engine bursts into flames you might want to kill the fuel.
5. ◴[] No.44538226[source]
6. bob1029 ◴[] No.44538263[source]
Disable the fuel system cutoff controls during the takeoff climb phase of flight. Once the aircraft loses contact with the runway, these controls shouldn't function without tripping certain thresholds (speed & altitude), or following a two-man procedure that is physically impossible to execute solo. In any other flight regime, the controls function as originally designed.

The danger of a burning engine is irrelevant if you are heading into terrain.

replies(3): >>44538396 #>>44538408 #>>44539894 #
7. lysace ◴[] No.44538334[source]
What you are really asking is: would we, the passengers, be safer without human pilots?

Eventually, yes. Soon? Maybe.

replies(2): >>44539295 #>>44539331 #
8. dboreham ◴[] No.44538393[source]
I can't put my car into reverse gear while driving down the freeway.
replies(6): >>44538475 #>>44538609 #>>44538674 #>>44538713 #>>44538994 #>>44539112 #
9. dboreham ◴[] No.44538396{3}[source]
Sounds good, but I'm not sure I trust Boeing outsourced software developers to implement that absolutely correctly.
10. yongjik ◴[] No.44538408{3}[source]
Now you created a fuel system cutoff control inhibition system which may malfunction in its own ways, e.g., refuse to cut off fuels from a burning engine because it thinks the plane is too low due to faulty altimeter reading.
11. stetrain ◴[] No.44538475{3}[source]
There’s no good reason to do that.

There may be a good reason to cut fuel to one engine shortly after takeoff.

You could have a system that prevents both switches being thrown, and only in the specific window after takeoff, but you’ve also now added two additional things that can fail.

12. arp242 ◴[] No.44538609{3}[source]
You also can't reverse a plane while flying it...

This is a rather odd comparison. You can slam the brakes, yank the steering week, and do all sorts of things to intentionally make the car crash.

replies(1): >>44539783 #
13. sgentle ◴[] No.44538674{3}[source]
Sure, but you can open the door, pull the handbrake, or turn the wheel so hard you lose control of the vehicle. These are all similarly preventable, but maybe not worth the risk of being unable to open the door, brake or steer if the safety mechanism fails closed, or if your situation is outside the foresight of its designer.

Also, you don't need multiple certifications and 1500 hours of experience to drive a car.

replies(1): >>44539569 #
14. berti ◴[] No.44538713{3}[source]
You can turn the ignition off. The reversers will not unlock on an airliner that's airborne either.
15. WalterBright ◴[] No.44538994{3}[source]
Remember the "surging" incidents where the driver insisted he was stepping on the brake but was actually stepping on the gas?
replies(1): >>44541988 #
16. testing22321 ◴[] No.44539112{3}[source]
A friend did exactly that in a manual transmission, doing 100km/h.

She was mad and said she has to jam it hard ( going for 5th and missed), but it went into reverse. And the gearbox literally hit the road when she let out the clutch.

17. celticninja ◴[] No.44539295[source]
Dog and a pilot. The pilot is there to make sure everything is ok and the dog is there to bite the pilot if he tries touching anything
18. bigbuppo ◴[] No.44539331[source]
As long as you also eliminate the possibility of maintenance problems and defects in automation, and have perfect microscale weather forecasts, and still have overrides for the human safety pilot that can still... wait a minute.
19. emmelaich ◴[] No.44539569{4}[source]
On a Tesla (and presumably other cars) opening the door engages Park.

There's no handbrake to pull, and turning the wheel so hard to lose control is next to impossible. Maybe on an oily wet or loose surface.

replies(2): >>44539858 #>>44540256 #
20. emmelaich ◴[] No.44539579[source]
At least an audible alert.
replies(2): >>44539633 #>>44541457 #
21. anonzzzies ◴[] No.44539633{3}[source]
Exactly
22. ExoticPearTree ◴[] No.44539761[source]
> Why can the pilot shut off the fuel during takeoff?

Engine failure during takeoff.

Engine fire.

23. imoverclocked ◴[] No.44539783{4}[source]
You can put the reversers on for a tactical descent though :P
replies(1): >>44539876 #
24. ExoticPearTree ◴[] No.44539858{5}[source]
There are very few failure scenarios that are life threatening in a car.
25. ExoticPearTree ◴[] No.44539876{5}[source]
They look nice, but they can be turned on the C17 (and probably other military airplanes).

Commercial airplanes have safeguards against in-flight thrust reverser deployment. That is why they only work in tandem with the ground sensing systems - like the airplane must firmly believe both main landing gears to be physically on the ground for both reversers to be operational.

26. ExoticPearTree ◴[] No.44539894{3}[source]
> The danger of a burning engine is irrelevant if you are heading into terrain.

Not quite. When you hit the ground you do not want any fuel leaks or hot surfaces as much as possible. That is why for example engines are shutdown when doing an emergency belly landing, to try abd prevent the airplane from bursting into flames.

27. ojosilva ◴[] No.44540256{5}[source]
On my Tesla Model Y there's a hand brake on the push button of the right lever. On the left hand lever there's another push button, the windshield wiper liquid. Guess what have I mistakenly, and scarely, done twice already when driving at highway speeds when my windshield was a little dusty?

New designs are prone to ill decision-making from engineers, drivers and pilots alike. Every pathway of let's do it differently is the beginning of a journey of fine-tuning loops until stability.

28. wezdog1 ◴[] No.44541457{3}[source]
Yeah that would have completed prevented this scenario /s
29. yard2010 ◴[] No.44541988{4}[source]
Remember when the driver pushed nothing but the tesla kept driving or braking?