Ask HN: Are mobile phones on a plane taking off or landing really dangerous? • Hacker News Board

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#81

Post by MichaelGG » Mon, Sep 27, 2010, 4:35 PM UTC

eli wrote: post #31

From the press release for a Carnegie Mellon study in 2006: "We found that the risk posed by these portable devices is higher than previously believed," said Bill Strauss, who recently completed his Ph.D. in EPP at Carnegie Mellon. "These devices can disrupt normal operation of key cockpit instruments, especially Global Positioning System (GPS) receivers, which are increasingly vital for safe landings." Strauss is an…

Seems like GPS for landing is poor dependency, considering how easy it is to jam GPS...

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#82

Post by borism » Mon, Sep 27, 2010, 4:38 PM UTC

a-priori wrote: post #41

artmageddon wrote: post #38

This is strictly anecdotal evidence, but I'll throw in my 2 cents here. I have a private pilot certificate and am working toward an instrument rating right now, which involves being in continuous contact with air traffic control, flying in low / zero visibility conditions, and relying on aircraft instruments to guide me on landings. On numerous(if not all), I've had my iPhone with me, switched on and even in my lap a…

We can all agree that a four-seater Cessna and 767 are very different, but for nav/comm they all use the same instrument systems. Unlike a Cessna, a 767 has a fly-by-wire system supported by a data bus (e.g. ARINC-429) running the length of the aircraft, often close to the passenger cabin. Presumably, GSM/CDMA signals could interfere with this.

767 doesn't have fly by wire - 777 was the first passenger Boeing to get it. But it does have a lot of wiring.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#83

Post by rakkhi » Mon, Sep 27, 2010, 4:41 PM UTC

runjake wrote: post #77

Former avionics tech here. Not scientific, but I've seen CDMA devices interfere with nav equipment, and GSM devices interfere with communications system (ala the infamous dat-dit-dah GSM sound over speakers). And these on nuke-hardened (EMP-shielded) military systems. These issues aren't going to crash the plane, however with the sheer variety of cellular devices, it's just a good idea to keep them off. Besides, you…

Not farmville but I enjoy reading on my phone, RSS feeds, kindle books, Instapaper. etc. Short flights espeically in the EU e.g. 1.5 hours to Amsterdam on the weekend in great time to catchup on reading. Missing the takeoff and landing cuts about 30 minutes of reading time.

It sounds selfish and there is enough evidence here that I am now happy to just turn my phone off, maybe I will just print off some of my Instapaper articles :)

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#84

Post by borism » Mon, Sep 27, 2010, 4:41 PM UTC

MichaelGG wrote: post #81

eli wrote: post #31

From the press release for a Carnegie Mellon study in 2006: "We found that the risk posed by these portable devices is higher than previously believed," said Bill Strauss, who recently completed his Ph.D. in EPP at Carnegie Mellon. "These devices can disrupt normal operation of key cockpit instruments, especially Global Positioning System (GPS) receivers, which are increasingly vital for safe landings." Strauss is an…

Seems like GPS for landing is poor dependency, considering how easy it is to jam GPS...

That's why RNAV (GPS) approaches are still not allowed (for commercial flights) AFAIK.

30 degree error has nothing to do with GPS though. Probably DVD player interfered with Localizer signal.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#85

Post by proee » Mon, Sep 27, 2010, 4:42 PM UTC

artmageddon wrote: post #38

This is strictly anecdotal evidence, but I'll throw in my 2 cents here. I have a private pilot certificate and am working toward an instrument rating right now, which involves being in continuous contact with air traffic control, flying in low / zero visibility conditions, and relying on aircraft instruments to guide me on landings. On numerous(if not all), I've had my iPhone with me, switched on and even in my lap a…

"Despite incoming calls and SMSs during these flights, not once have any of the instruments been affected by the phone."

Without a fixed reference you have no way to verify this statement. Even if you crossed reference your flight instrument data with a ground-based reference it would not account for intermittent errors that could occur.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#86

Post by borism » Mon, Sep 27, 2010, 4:46 PM UTC

rakkhi wrote: post #83

runjake wrote: post #77

Former avionics tech here. Not scientific, but I've seen CDMA devices interfere with nav equipment, and GSM devices interfere with communications system (ala the infamous dat-dit-dah GSM sound over speakers). And these on nuke-hardened (EMP-shielded) military systems. These issues aren't going to crash the plane, however with the sheer variety of cellular devices, it's just a good idea to keep them off. Besides, you…

Not farmville but I enjoy reading on my phone, RSS feeds, kindle books, Instapaper. etc. Short flights espeically in the EU e.g. 1.5 hours to Amsterdam on the weekend in great time to catchup on reading. Missing the takeoff and landing cuts about 30 minutes of reading time. It sounds selfish and there is enough evidence here that I am now happy to just turn my phone off, maybe I will just print off some of my Instapa…

There are offline RSS readers, Kindle apps and Instapaper saves can be exported to various formats.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#87

Post by illumin8 » Mon, Sep 27, 2010, 4:48 PM UTC

borism wrote: post #79

byrneseyeview wrote: post #52

Earlier quoted context omitted.

Your unspoken premise is that the FAA 1) Cares about safety (more than they care about appearing to care), and 2) That they know what they're doing.

If you don't feel safe enough flying in US under FAA you can try some more liberal on safety places like Africa or Indonesia. Your survival chances decline can be calculated quite precisely though.

Exactly. There have been several years in the last decade where there were absolutely zero fatalities on US airlines. Say what you want about idiotic security rules, but strict safety measures seem to be working pretty well for us.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#88

Post by mattmiller » Mon, Sep 27, 2010, 4:51 PM UTC

_b8r0 wrote: post #47

Two things: 1. Using a mobile phone isn't generally dangerous providing everything else on the plane works fine and nothing would be interfered with if it wasn't. 2. Cell handovers at 30,000ft with an air speed around 500mph are really, really hard. The reasons for turning your phone off during takeoff and landing are wide and varied, but the long and short of it is that it effectively counts as security theatre. Tak…

Since most phones are CDMA now I think the dangers of interference are much much lower. I have always suspected that carriers help promote this myth to reduce network overhead from point 2 above.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#89

Post by runjake » Mon, Sep 27, 2010, 4:53 PM UTC

rakkhi wrote: post #83

runjake wrote: post #77

Former avionics tech here. Not scientific, but I've seen CDMA devices interfere with nav equipment, and GSM devices interfere with communications system (ala the infamous dat-dit-dah GSM sound over speakers). And these on nuke-hardened (EMP-shielded) military systems. These issues aren't going to crash the plane, however with the sheer variety of cellular devices, it's just a good idea to keep them off. Besides, you…

Not farmville but I enjoy reading on my phone, RSS feeds, kindle books, Instapaper. etc. Short flights espeically in the EU e.g. 1.5 hours to Amsterdam on the weekend in great time to catchup on reading. Missing the takeoff and landing cuts about 30 minutes of reading time. It sounds selfish and there is enough evidence here that I am now happy to just turn my phone off, maybe I will just print off some of my Instapa…

I definitely see your point and sympathize (as a busy dad who often gets only 5 minute reading breaks), but even if you aren't gabbing away or noisily typing, most flight environments are dark, and those LCDs leave annoying visual tracers for anyone in your periphery. Can't argue that on a Kindle though :)

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#90

Post by runjake » Mon, Sep 27, 2010, 4:54 PM UTC

runjake wrote: post #77

Former avionics tech here. Not scientific, but I've seen CDMA devices interfere with nav equipment, and GSM devices interfere with communications system (ala the infamous dat-dit-dah GSM sound over speakers). And these on nuke-hardened (EMP-shielded) military systems. These issues aren't going to crash the plane, however with the sheer variety of cellular devices, it's just a good idea to keep them off. Besides, you…

To expand on my comments, the comm interfence could interrupt voice and data comms transmissions. Although in the latter, it's more like someone picking up the phone while you're dialed into your favorite BBS.