Forgot your password?
typodupeerror

Comment: Re:but, back to root cause (Score 1) 423

by DieByWire (#44229095) Attached to: Malcolm Gladwell On Culture and Airplane Crashes

Is the 777 one of those planes which cannot be landed fully automatically? What are the current FAA rules about auto-landings? I thought planes were generally supposed to use manual landing only under severe weather or other concerns.

The 777 most certainly can do what's known as an 'autoland.' However, it needs a fully operational ILS (Instrument Landing System) to do it. The vertical guidance (glideslope) portion of the ILS for runway 28L was out of service due to the runway construction, so an autoland was not possible.

Autolands are also the exception, not the norm. They are generally done when the visibility is so poor that the pilot can not adequately see the runway, or when maintenance asks the pilot to perform one to periodically verify autopilot performance. Autolands require that the ILS signal not be interfered with at all which puts some additional restrictions on ATC.

Comment: Re:Pilot error? (Score 1) 506

by DieByWire (#44207397) Attached to: Boeing 777 Crashes At San Francisco Airport

You're not a pilot, you're a passenger, and an arrogant one at that. The "auto landing" they were referring to was probably the ILS -- it's a beacon that is positioned at the start of the runway and allows for instrument landings. Every landing is an "auto" landing on a passenger craft because they're flying instrument flight rules.

They do not just push a button in the cockpit and then nip off for a bit of tea while the plane magically lands.

girlintraining, let's give you a little more training, since you obviously need it.

The ILS ( Instrument Landing System ) provides vertical and lateral guidance to the touch down zone of the runway. 'Beacon' is usually used to refer to an NDB (Non-Directional Beacon).

The pilot may follow ILS guidance manually, or he may 'couple' the autopilot to the ILS and have the autopilot fly the approach. Typically they disconnect the autopilot at low altitude and land manually.

Most airliners built since the 80's have 'autoland' capability. That means that in addition to flying the approach, the autopilots have the ability to complete the flare, landing and rollout without intervention of the pilots. When the visibility goes below certain minimums autoland is the only way you can legally or practically land the aircraft. Pilots (and the aircraft itself) monitor autolands very closely for signs of failure.

They do not just push a button in the cockpit and then nip off for a bit of tea while the plane magically lands.

Correct, there are multiple buttons, for multiple redundant autopilots. And you're correct, no tea. We're already pretty wired at this point.

For the others confusing 'fly-by-wire' with autoland, fly-by-wire refers to pilots control inputs feeding a computer which in turn commands the flight controls to move. Airbus A320 and later and Boeing 777 and later use fly-by-wire.

In earlier aircraft, there is no computer intermediary between the pilots controls and the control surfaces. Essentially, it's just cables and hydraulics between the two.

Autolands are routinely accomplished by both fly-by-wire and conventionally controlled airliners.

Comment: Re:Open airplanes (Score 3, Insightful) 506

by DieByWire (#44207285) Attached to: Boeing 777 Crashes At San Francisco Airport

This will be pilot error.

Possible. Statistically speaking, you could say that about any crash without any evidence and you'd be right more often than wrong. But it's by no means guaranteed, and the evidence isn't in yet.

Remember BA at Heathrow?

My guess is improper flap position.

You will be shown to be wrong. Guaranteed.

But he was trying to land with no flaps on a flaps approach.

Really. Thank you for informing us of this fact. Amazing how the leading edge magically deployed itself after the crash.

The only other thing I guarantee right now is that this thread will spout uninformed, infuriating drivel like the AF447 articles did.

Single engine is AK is very different from airline and transpac flying. Please spare us your conclusions based on zero evidence or relevant experience. It's painful enough as it is without hearing such drivel.

Comment: Re:What happens to the carbon dioxide? (Score 2) 365

by DieByWire (#42975349) Attached to: New Process Takes Energy From Coal Without Burning It

The CO2 can be fed to algae tanks to continue another energy production process. It would be easier than doing the same with traditional coal plant if the CO2 is clean and not mixed with ash etc.

And when you burn the oil you got from the algae that formerly fossil CO2 is now in our atmosphere. So maybe you got more energy per ton of CO2 out of it than we normally would. You're still filling the atmosphere with fossil carbon.

'Clean coal' is marketing, pure and simple.

Comment: Re:Lithium ion battery (Score 2) 151

by DieByWire (#42521825) Attached to: Boeing Dreamliner Catches Fire In Boston
Interesting - I knew the engines were no bleed but didn't realize the APU was also. Nevertheless, the point I was trying to make is that the APU battery is used for the APU, not for powering the whole aircraft when the engines are shutdown, and that it stays powered and charging even when the APU is not in use.

Comment: Re:Lithium ion battery (Score 3, Informative) 151

by DieByWire (#42518565) Attached to: Boeing Dreamliner Catches Fire In Boston

But if it was the ground power battery pack that powers the plane when the engines are off, how likely would it have started while flying?

The battery in question doesn't power the aircraft. It's used to power the control circuitry and starter of the auxilary power unit (APU). The APU is a small turbine engine used to generate electrical power and high pressure bleed air for engine starting, or if additional electrical power is needed in flight ( follwing a generator failure, for example.)

I can't speak specifically to the 787, but APU batteries are typically always connected and kept charged in case you need to start the APU without any other source of power. I would assume it can be remotely disconnected as it can be on other aircraft, but once the battery is on fire electrically isolating it is not going to solve your woes.

An inflight fire, especially in an aircraft that could be three hours from shore, is a scary, scary thing.

Sentient plasmoids are a gas.

Working...