Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Why you can't get cell service on the tarmac

thepointsguy.com

Post reply on HN
Print view View original

31–40 of 46 posts

Re: Why you can't get cell service on the tarmac

#31

Post by caleblloyd »

beatgammit wrote: post #4
bobowzki wrote: post #3

Earlier quoted context omitted.

And you are inside a metal tube that does a good job of shielding I suspect, at least if you are not close to a window.

Any they don't turn in WiFi until they're in the sky because they don't want people on their devices (and I'm sure there are technical reasons as well).

Commercial Airlines use either Air To Ground (ATG), satellite, or both to deliver internet. When the plane is on the ground it can't see the ATG towers. So 10,000ft is both a regulatory and a technical limitation for ATG.

Re: Why you can't get cell service on the tarmac

#32

Post by Frqy3 »

scblock wrote: post #6

This is not an issue I have ever experienced. I can’t get reliable coverage in my office but planes on the ground seem to be fine (mostly Denver, Detroit, Minneapolis, Des Moines). Maybe it affect some airports more than others.

The author has extrapolated their experience in (at most) a handful of airports to the general case.

One of the first projects I was given as a junior engineer was to measure signal strengths of our and competitor mobile networks at the local airport. This was pre September 11, but I was still amazed at the access we got carrying a signal analyser and just flashing our employee badges got us.

For inbound roaming users, absent particular partner network preferences (which were less common back then), the mobile device would select the local network to use based on relative signal strengths when turned on. Capturing those inbound roaming fees was a high priority for the product managers and hence a lot of effort and infrastructure investment went into this.

Re: Why you can't get cell service on the tarmac

#33

Post by PopeDotNinja »

scblock wrote: post #6

This is not an issue I have ever experienced. I can’t get reliable coverage in my office but planes on the ground seem to be fine (mostly Denver, Detroit, Minneapolis, Des Moines). Maybe it affect some airports more than others.

I've noticed poor mobile reception on the tarmac at both Oakland and San Francisco airports in California. The airports are both have runways that are right on the water, which presumably means they are about as far from mobile towers as one can be at an airport. I'd guess that landlocked airports have better reception.

Re: Why you can't get cell service on the tarmac

#34

Post by tom_mellior »

> While just about everyone knows to turn their cellphone off or on airplane mode once the plane takes off, there’s no rule against using it while your plane is on the ground.

In my experience it's not uncommon (but also far from universal) to hear some version of "please leave your phones in airplane mode until we have reached the terminal" after landing.

Re: Why you can't get cell service on the tarmac

#35

Post by [deleted] »

TheSpiceIsLife wrote: post #13
ajdlinux wrote: post #10

Earlier quoted context omitted.

When I go into an airport terminal with lower ceilings (e.g. parts of Melbourne Airport) I feel _noticeably_ more cramped and claustrophobic. It really does make the experience feel worse for me. I'm not entirely sure why it makes me feel that way.

Melbourne airport is the one that instantly popped in to my mind as it's the airport I've spent most time in. And yeah, there are a couple of noticeably lower ceilings in there. But, I wouldn't be surprised to discover that tests have shown people become much more agitated in crowded places with regular (is it 8' / 2400mm?) ceilings. I can't imagine that scenario would make me feel at ease.

[deleted]

Re: Why you can't get cell service on the tarmac

#37

Post by antihero »

coding_unit_1 wrote: post #30
dijit wrote: post #28

Earlier quoted context omitted.

Our phones GSM bands interfere with unsheilded radios. The effect is most prominent when you’re getting a call and you’re close to a hifi system. Often you can tell that your phone is about to ring before the phone even begins to vibrate or chime. https://www.quora.com/Why-do-speakers-make-noise-when-mobile... There is a high likelihood that this isn’t a problem now and hasn’t been a problem for some time; but it mig…

If there was any danger of mobile phones interfering with aircraft systems then they wouldn’t rely on the general public following instructions to make it safe.

This is the logic I've always held - if it's actually dangerous, they wouldn't allow it on board.

Re: Why you can't get cell service on the tarmac

#39

Post by gpderetta »

dijit wrote: post #28
alpb wrote: post #27

Earlier quoted context omitted.

Does anything actually happen if nobody switches their phone to airplane mode and kept watching videos on YouTube? I have witnessed some people do the policing on behalf of flight attendees, but I'm never sure enough to say that rule has no scientific basis.

Our phones GSM bands interfere with unsheilded radios. The effect is most prominent when you’re getting a call and you’re close to a hifi system. Often you can tell that your phone is about to ring before the phone even begins to vibrate or chime. https://www.quora.com/Why-do-speakers-make-noise-when-mobile... There is a high likelihood that this isn’t a problem now and hasn’t been a problem for some time; but it mig…

I remember the incoming call interference being being a thing in 2G times (late 90s, early 00s), but I haven't experienced it in a very long time. Do digital protocols cause less interference (possibly due to frequency hopping or just running on different frequencies)?

edit: 2G was also digital.

Re: Why you can't get cell service on the tarmac

#40

Post by gtirloni »

tptacek wrote: post #2

I'm ruining a good article, but I'll summarize: you can't build good coverage in an airport with cell towers because of height restrictions, so airports augment their coverage with indoor repeaters; once you get on the plane, you're out of range of the indoor repeater network.

Thanks, I had to read at least until the 4th paragraph to get any useful information.
Post reply on HN