riddler 0 #1 June 19, 2003 Question for jump pilots. I know using a cell phone on a commercial plane can effect instruments/communications. I would like to know if carrying/using a cell phone on a jump plane will also effect instruments/communications. I don't know which instruments are effected on commercial planes, or if jump planes even have those types of instruments, so I'm seeking a little enlightenment. I don't expect to use the phone to talk - way too noisy for that. But I have a GPRS that can surf the web and get email. I can get AWOS info via the phone's Internet capability, which is nice to know right before you jump. Just wondering how feasible that is. Also, if I carry the phone to make a call in case I land out, should I completely turn it off even if I'm not talking on it? It's still going to do some GPRS checking (for voice mails/email/etc) even if I'm not talking on it. Quote Share this post Link to post Share on other sites
PhreeZone 20 #2 June 19, 2003 Just a side note on Cell phones, they only really work up to about 3000 agl from my experience. I've taken one on jumps where I know I'm landing off (turned it off to avoid issues), and I've also made a phone call under canopy before and it took till about 3000 feet to get a signal. This is in the midwest with towers ever few miles and you can see for a long ways since everything is flat. Unless you are hoping only to do hop and pops the phone is useless in the plane for AWOS info in my experiences.Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
AndyMan 7 #3 June 19, 2003 QuoteQuestion for jump pilots. I know using a cell phone on a commercial plane can effect instruments/communications. I would like to know if carrying/using a cell phone on a jump plane will also effect instruments/communications. I can't answer the pilots point of view, but I can tell you that you'll be breaking FCC regulations, which have potential jail time as penalties. Yes, the FAA bans cellphones in planes because of interference - but - the FCC also bans cellphones in planes because they can "see" too many celltowers at once, and it can screw up the cell system. If I'm intentionally bringing a cellphone - ie, a crosscountry, then I'll turn it off in the plane. _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites
Faber 0 #4 June 19, 2003 in DK your cell phone dont work above aprox 5000ft,we bring them when we make long distance fligths under canopi.I normaly shut it down before entering the plane and switch it on as im back on the ground Stay safe Stefan Faber Quote Share this post Link to post Share on other sites
billvon 3,100 #5 June 19, 2003 >I would like to know if carrying/using a cell phone on a jump plane will >also effect instruments/communications. I don't know which instruments >are effected on commercial planes, or if jump planes even have those >types of instruments, so I'm seeking a little enlightenment. On most modern aircraft, nothing will be affected. On older aircraft, the GS receiver, the ADF and Stormscopes can sometimes be affected, at least according to our tests. Note that these are all IFR navigation instruments. >Also, if I carry the phone to make a call in case I land out, should I >completely turn it off even if I'm not talking on it? Yes; it will try to register as it sees new cells. >I can't answer the pilots point of view, but I can tell you that you'll be > breaking FCC regulations, which have potential jail time as penalties. Interestingly, there was never a similar regulation passed concerning PCS phones. No doubt just a loophole. Quote Share this post Link to post Share on other sites
quade 4 #6 June 19, 2003 Quote >Also, if I carry the phone to make a call in case I land out, should I >completely turn it off even if I'm not talking on it? Yes; it will try to register as it sees new cells. Can you explain how this differs from what normally happens when you drive down the freeway and enter different cell sites or drive over a hill and are exposed to a lot of different cell sites? I'm sure there's something I'm missing, but I can't really see how it's any different.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
Jib 0 #7 June 19, 2003 I thought digital phones don't work that high because the antennas are pointed down and the signal is weaker, but analog has a lot longer range. -------------------------------------------------- the depth of his depravity sickens me. -- Jerry Falwell, People v. Larry Flynt Quote Share this post Link to post Share on other sites
freakydiver 0 #8 June 19, 2003 That's odd - I was just camping above Aspen Colorado at 11,452 feet and made numerous calls out on my celly... -- (N.DG) "If all else fails – at least try and look under control." -- Quote Share this post Link to post Share on other sites
FliegendeWolf 0 #9 June 19, 2003 Where you were presumably below 3000 ft AGL.A One that Isn't Cold is Scarcely a One at All Quote Share this post Link to post Share on other sites
diverdriver 7 #10 June 19, 2003 I'll have you know that both on the Dornier 328 prop and the Canadair Regional Jet CL-65 I can hear when a cell phone is on. I get clicking noises in my headphones. Hopefully no one says anything important to me just as the clicks happen. Look HERE for a report on an uncommanded gear retraction during landing. A cell phone was suspected of causing the gear retraction but it could never be proven. No other cause was found.Chris Schindler www.diverdriver.com ATP/D-19012 FB #4125 Quote Share this post Link to post Share on other sites
riddler 0 #11 June 19, 2003 Quotethey only really work up to about 3000 agl from my experience. I climb a few 14ers every year (mountains above 14,000 feet ASL - Colorado has 55 of the 67 in the states). Anyway, we use our cell phones all the time from the top of the 14ers. Call our friends: friend: "Hello?" me: "Guess where I am?" friend: "Why the Hell are you calling me at 9 am on a Saturday morning??" Some of them have 5,000 foot ascents. But we do notice that some carriers work better than others - I wonder what sort of regulations about range the cell towers have? Quote Share this post Link to post Share on other sites
billvon 3,100 #12 June 19, 2003 >Can you explain how this differs from what normally happens when > you drive down the freeway and enter different cell sites or drive > over a hill and are exposed to a lot of different cell sites? On analog phones, it's a frequency reuse problem. Imagine a hexagonal grid of cells. Each one has a set of frequencies it can use, unique from its neighbor. Outside that set of neighbors, the frequencies can be reused because a phone 2 cells away can't receive the signal from the phone; it's too far away. In the air that's not the case, so either you hear several conversations as you "blunder into" a cell that's not expecting to hear your signal, or you 'lock out' those frequencies over a wide range of cells. On digital phones, you run out of Eb/No. That's symbol strength to jammer strength, the CDMA equivalent of SNR. Essentially the phone can hear all of the cell site transmitters out there, and thus No goes up significantly. On the ground, if enough phones are in the air, the receiver's No goes up a lot as well, since 20 phones can blanket 20 cellsites with their signal instead of just 1 or 2 each. Quote Share this post Link to post Share on other sites
billvon 3,100 #13 June 19, 2003 >I'll have you know that both on the Dornier 328 prop and the > Canadair Regional Jet CL-65 I can hear when a cell phone is on. I > get clicking noises in my headphones. Yeah, we've heard that on analog and GSM phones; we didn't research them much since we were interested in CDMA interference. I also get a little periodic "yip" on my headset when the wingtip strobes are on on a 172 that I fly; I've noticed that several aircraft will give you clicks when large power users are turned on and off. Quote Share this post Link to post Share on other sites
BlueEyedMonster 0 #14 June 19, 2003 QuoteI get clicking noises in my headphones. That happens with any unshielded speaker in close proximity to a cell phone. QuoteLook HERE for a report on an uncommanded gear retraction during landing. A cell phone was suspected of causing the gear retraction... That report does not mention anything about a cell phone. Quote ...but it could never be proven. No other cause was found. Does this mean that if you can't find a cause it was a suspected cell phone? That is not very scientific/logical. Aren't most jump planes, at least at smaller DZ's, VFR? I jump with a phone occasionally, not to make calls, but in case of emergency or an off landing. The pilots and DZO are aware I have done this, and actually think it is a good idea--especially after one of our jumpers had an off landing at another DZ. He laid in a ditch with a broken pelvis for 45 minutes before someone found him. Quote Share this post Link to post Share on other sites
PhreeZone 20 #15 June 19, 2003 AGL and ASL are two totally different things. In talking to a few Verizon field reps they said they have their cell coverage in a profile that covers as much of the surface as possible and the only things reaching more then a few hundred feet up is left over signal strength based on the coverage cone of the antenna. In mountianous places they have signal splash going higher they they do on areas that are flat like the midwest. Since a mountian top is only 0 agl they would'nt have to worry about needing to go any higher Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
diverdriver 7 #16 June 19, 2003 QuoteYeah, we've heard that on analog and GSM phones; we didn't research them much since we were interested in CDMA interference. I also get a little periodic "yip" on my headset when the wingtip strobes are on on a 172 that I fly; I've noticed that several aircraft will give you clicks when large power users are turned on and off. Well sure. And there's the alternator whine you can get. But those are wired into the electrical system already. When I hear clicking from a cell phone I have to wonder what else it is effecting from the outside.Chris Schindler www.diverdriver.com ATP/D-19012 FB #4125 Quote Share this post Link to post Share on other sites
diverdriver 7 #17 June 19, 2003 Of course the report says nothing about the cell phone theory. There's no proof. This is from my company. I have a bit more of the inside than most. Quote Share this post Link to post Share on other sites
freakydiver 0 #18 June 19, 2003 Sure - but come on 12 grand on the top of a freakin mountain where I highly doubt there are towers all over the freakin place... Bringing cell phone with me tomorrow on jump because I don't buy the 3000 AGL law. And what about 14ers here in Colorado, technically I am above 3000 AGL considering many of them have 4000 of vertical to cover to get to the top... OOPs, I see riddler has covered that issue... -- (N.DG) "If all else fails – at least try and look under control." -- Quote Share this post Link to post Share on other sites
BlueEyedMonster 0 #19 June 19, 2003 QuoteOf course the report says nothing about the cell phone theory. There's no proof. This is from my company. I have a bit more of the inside than most. Does your insight give you anything to support this cell phone theory other than pure speculation? I believe billvon's facts about signal sharing is the real reason for the regulation. Who is going to actually turn off your phone if I asked you to because of signal sharing--which is a very valid reason to keep them off at altitude. But, I bet you will turn off that phone if I tell you it will crash the plane. After hearing that a turned on cell phone will crash planes flight after flight it becomes believed to be a fact. Then it becomes speculation in unexplained incidents. Its the stuff urban legends are made of. Especially when someone as respected and experienced as you repeats it. Quote Share this post Link to post Share on other sites
faulknerwn 38 #20 June 19, 2003 Mine usually works until about 10,000 feet. I've received a call on the ground from someone else who was at 10k too and albeit from a little static, it was fine. W Quote Share this post Link to post Share on other sites
quade 4 #21 June 19, 2003 Various stories. http://www.cnn.com/2001/BUSINESS/asia/09/17/hk.airbornecellular/index.html http://www.caa.co.uk/caanews/caanews.asp?nid=669quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
PhreeZone 20 #22 June 19, 2003 How are you 3000 agl if your standing on a mountian top? Sure, your 3000 feet above the valley below but not above the ground. Antenna's and coverage areas come in all shapes and sizes. Some are very focused, some are parabolic that share the signal equally in all directions but most are hybrids that focus the majority of the signal to where its going to be used 99% of the time, on the ground.Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
AndyMan 7 #23 June 19, 2003 QuoteInterestingly, there was never a similar regulation passed concerning PCS phones. No doubt just a loophole. Correct. The FCC's airborne cellphone prohibition is in Part 22, which is specific to 800 MHz cellular service; there is no corresponding rule in Part 24, which governs PCS. (IIRC) I presume the same issues apply. I am SUCH a geek. _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites
LouDiamond 1 #24 June 19, 2003 parabolic antenna: An antenna consisting of a parabolic reflector and a radiating or receiving element at or near its focus. Note: If the reflector is in the shape of a paraboloid of revolution, it is called a paraboloidal reflector; cylindrical paraboloids and off-axis paraboloids of revolution are also used. omnidirectional antenna: An antenna that has a radiation pattern that is nondirectional in azimuth. Note: The vertical radiation pattern may be of any shape."It's just skydiving..additional drama is not required" Some people dream about flying, I live my dream SKYMONKEY PUBLISHING Quote Share this post Link to post Share on other sites
BlueEyedMonster 0 #25 June 19, 2003 QuoteVarious stories. http://www.cnn.com/2001/BUSINESS/asia/09/17/hk.airbornecellular/index.html http://www.caa.co.uk/caanews/caanews.asp?nid=669 I love it when two articles contradict eachother! However the second, is from the UK. In Europe they use different frequencies and standards for their phones. And, when I pilot sees a malfunction, how does he know its not a laptop, a cd player, or flying 5000ft above a 100,000 watt radio transmitter that is actually causing the problem? Edit to add: I think the best thing would be to respect the FCC's decision based on the shared frequency issue. Take your phone with you for emergencies and off landings, but make sure it is turned off on the plane. Quote Share this post Link to post Share on other sites
