Aviation thread

Discussion in 'General Chat' started by DIGGS, May 31, 2017.

  1. I only get nervous during takeoff and landing, because of sharp turns and engines reducing rpm when you don't expect them haha. When i'm 39.000 feet in the air i'm fine.

    I also don't really like the part where the gulf of bengal meets india. Always turbulence there. Not scared of it, but it's annoying.
     
  2. That's actually a much more difficult question that it seems at face value, because the efficiency, thrust, and power of jet engines all change pretty dramatically with altitude and speed, as do the aerodynamics of aircraft. When losing an engine, a plane might move to a different altitude and speed that gives them better range for that number of engines and thrust available.

    As such, it's easier to look at this problem from the regulatory perspective than the physical side. There's a certification program called ETOPS that basically dictates how far a plane is allowed to be from the closest possible diversion airport at any given time, in case of an emergency. For many years, the highest rating was ETOPS-180, or 180 minutes flight time. Meaning even if an aircraft could fly for much longer on one engine, no certification agency trusted an operator to do so. However, with new generations of turbofans, starting with the Boeing 777 and Airbus A340, ETOPS ranges have steadily been growing, first to 240-minute and now I think as much as 370 minutes for new composite aircraft. This is equivalent to about ~4500km flying distance. Given the many diversion airports available (the US and UK allow the use of their remote, far-flung military bases as diversion airports), this means that a modern jet like an A350XWB or a 787, or the long-range versions of the 777, can basically fly almost anywhere in the world and be in safe distance from a diversion airport.
     
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  3. YES. We flew from KL to Sri Lanka at night.... wasnt happy.
    But yea, I do hate that part when the rpm goes down. Sounds like they turn off :|
     
  4. Interesting, i did not know that. Thanks for clearing that up.
     
  5. Haha, i have to pass that area twice this year. Not too happy about it either.
     
  6. The sharp turns mean that the autopilot is following the designated flight path from waypoint to waypoint as it should. And fluctuating RPM means that FADEC is throttling the engine to keep the airspeed constant. No need to get nervous!

    Modern twinjets are able to take off, execute go-arounds and climb with one engine inoperative. If both engines fail, a ram-air turbine will deploy to produce hydraulic power for the control surfaces of the aircraft and emergency electricity. Unless the aircraft happens to be above the Himalayas or something, there's still a good chance that the aircraft can glide safely to an airfield or execute an emergency landing. Air Transat flight 236 and Air Canada flight 143 are good examples of this. The US Airways Flight 1549 suffered total power loss at mere 2800 feet and 215-ish knots, yet the captain managed to successfully ditch the aircraft without any loss of life. There's even a decent movie about the incident (Sully 2016) by Clint Eastwood, do watch.

    Here's a reconstruction of the event:

     
  7. But landing at 350 knots would be most unsafe. And by unsafe I mean guaranteed destruction of the aircraft and everyone on board.
     
  8. I'm aware of this. I read a lot about aviation and follow some pilots on youtubes. But still, i just don't like that i'm not in control.
     
  9. im glad im not control because i dont know how to drive an airplane
     
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  10. This is now an aviation thread

     
  11. Ah, you just have to accept that you're never in control and that free will is a lie. Doesn't matter if you're in an airplane.
     
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  12. That's true
     
  13. For some reason I find the landing the most calming part... "thank god, its almost done!!!"

    Probably rather crash and die super quick on the runway, rather than fall out of the sky for minutes before. Or land in water, only to drown. **** THAT.
     
  14. that's low.

    speaking of low passes. i once was swimming in a lake in france and 3 fighter jets appeared out of nowhere. i shit you not, they were passing over at like maybe 10/15 meters above my head. bunch of nutjobs.
     


  15. still pretty sick
     
  16. did that not destroy your ears
     
  17. yes
     


  18. the shit around 2:06 is what always makes me feel nervous lol
     
  19. @Vanilla Ice With all the tesla's driving around, green power, limited supply of oil etc. Do you think there will be planes flying electric in the foreseeable future? Wether it be batteries or hydrogen?
     
  20. I think this came up in another thread, actually. A jet engine doesn't require combustion, it only requires heat addition. The use of combustion for that purpose is strictly an engineering choice, it could just as well be electric (or, if you live in the dystopia of 1960s America, nuclear). The only issue is that volatile chemicals are your best bet in terms of stored heat per kilo and per liter. I think that such volatile chemicals are going to stay around for awhile, but if we do properly wean ourselves from fossil fuels, there's no reason they can't be synthetics.

    Hydrogen has the energy per kilo, but not the energy per liter. Ethanol is ~50% off conventional fuels for both, but with higher-efficiency engines that might not be insurmountable - I suspect biofuels like this are the most promising. Batteries will require a vast, vast technological breakthrough - their energy density is still two or three orders of magnitude lower than chemical fuels.
     
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  21. This just flew near my city. HOLY **** ITS LOUD. I'm used to 747's being loud, but this is on another level. It made my windows vibrate. It was almost flying at 30,000ft. How is this possible, what the hell man.

    Schermafbeelding 2017-06-13 om 22.37.52.png
     
  22. After a couple of years of constant plane approaches, they shifted that route slightly south, to go over the poorer neighborhoods. No more plane noise for me.
     
  23. fly over those Palestinian dogs
     

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