I watched a program on tv that said you can't get a signal on a mobile/cell when you are at altitude.?

Question

Is it true?

Answer 1

Yep, it's true. I fly on my company's corporate jets from time to time. The crew don't care if we use our cellphones in flight; they swear it never interferes with comms or navigation. They work OK up to around 5,000 feet AGL. After that it gets spotty up to about 7,500 feet and is pretty much dead past that point. Also, at 500 - 600 MPH ground speed, you're moving too fast for the cell towers to get and keep a signal lock on your phone.

And just to shut the conspiracy theorists up, nearly all the calls placed from aboard the doomed aircraft on 9/11 were placed from the seatback Airphones, NOT from passenger's cellphones. Please read the 9/11 Commission's report! A couple of BRIEF calls may have made it through on cellphones but keep in mind that near the end they were all well below 5,000 feet AGL! Sheesh!

Answer 2

Ryanair ARE going to let people use mobile phones from 2007, but they are going to be using an interesting method to make this work. As others have already pointed out, the effect of 100+ phone/Blackberry users constantly switching from cell to cell at high speed would, in all likelihood, crash most networks. The jury is still out on the avionics question; in practice it probably has no real effect, but the power output of those 100+ phones could theoretically cause some issues.

Ryanair are working with a company called OnAir who will install equipment that will enable customers to use their mobiles on board. This equipment works at much lower power ratings than standard cells, and will use a combination of satellite communications and a couple of ground stations. Any calls made from a Ryanair aircraft will be treated as overseas calls by the users network, and will be subject to roaming charges; although these charges have yet to be confirmed, the likelihood is that they will be quite high!!!!

Answer 3

Thank God Bostonian and I are here to render some common sense. Cell towers are good for about a couple of miles, maybe, and since commercial airliners cruise at maybe 6-7 miles above the ground, simple math tells you that you're not going to get much if any signal after a couple of minutes into your flight. Even on the ground, remember that you're inside a metal structure packed with miles of wire that interferes with cell transmissions. There ain't no cell cervice a thousand miles out over the ocean, either. Or in a lot of remote areas that planes fly over. In-flight telephones use a different system than your cell phone does.

Answer 4

The real problem is not that you can't get a signal.

The problem is that you get signal EVERYWHERE in line-of-sight, so putting your phone on a channel locks up that channel on all the cells you're close enough to hit.  The cell antennas are highly directional and are pointed at the horizon so you'll eventually lose signal as you climb, but the real reason nobody wants you using a cell from a plane is because it messes up the cell network.

Using Vonage through a sufficiently good 802.11 system and people's open WiFi points might still work... ;-)

Answer 5

Strictly speaking you would have better coverage at altitude as there is nothing to interfere with the signal.

I believe what the TV program was trying to say is you cant get reception on a plane, and no, it has nothing or very little to do with airplane technology. Think about it, your travelling at 700mph at 28000 feet, there is no way your cellphone will have the strength to keep hold of a signal at that speed or height.

Answer 6

Well, your mobile/laptop/whatever has to seek and find the nearest reception facility. Not likely in, say, mid-atlantic.
Sat-phone, which I use on the boat works fine, but not ordinary mobiles or cellphones at a good;y height, or worse at sea level.
No link to the usual comms.systems..
Altidude therefore, as in comms.satellites are good. Stuck behind a mountain is not.
Interesting bits perhaps >
In the UK, you are not supposed to use a phone when in a hot air balloon, as it must be land-based. What nonsense ?
As for jumping out of small aircraft, it works fine to others on the way downwards. Altitude and attitude no problem.
So, OK if you are over a large population of folks, with luck, but no good in the middle of nowhere.
Grab a sat-phone if you want to stay in touch almost anywhere on the planet.
Best of luck,
Bob

Answer 7

I have heard stories of people using cell phones at altitude, so it may be possible.
However it was not possible in 2001, which makes all the stories related to passengers on hijacked aircraft during 9/11 a load of bull!

Answer 8

I've experimented with this up to about 10,000 ft. MSL by dialing my own number and trying to leave a voice message to see how the reception is. I never had any luck with it. I found I could however, start my car with my remote from the downwind leg of the approach. That's handy on a cold day!

Answer 9

No it is not true. I fly a lot on a corporate jet, my phone can pick up a signal 80% of the time we are airborne, and it functions porperly.

Answer 10

I fly every day as flight instructor and I lose service (Nextel) on my cell phone around 2000ft AGL. On the other hand my old phone (Alltel/Verizon) I could receive text messages and get service up to around 5000ft AGL in Florida.