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"TaxSrv" wrote in message ... Hey folks, let's not overdo the safety aspects here, so no one panics if aboard an airliner and sees someone using a radio. I doubt any device emitting small RF will be able to make comm reception unreadable. Even if it did, there are then fallback procedures which the pilot is required to know by heart, Your doubts do not stand up to empirical evidence. Stick to assertions that have a basis in fact and not just in your mind. The whole point is to not weaken the chain of redundant flight safety features just to allow a piece of meat cargo to be electronically entertained. Now the same considerations apply to flying the approach and landing, but the pilot would rather not have to deal with potential interference to either nav or comm, especially if the airport is 1/2 mile visibility in fog. Thus, it's not too uncommon for the pilot to grant permission to use a radio device only while in cruise. And all passengers will immediately comply, because they are all concerned about not creating a dangerous electronic environment. Games will be halted, spreadsheets closed, and porn movies terminated. Cabin attendants will notice immediate 100% compliance, and will not be distracted from other duties to repeatedly remind, cajole or threaten recalcitrant passengers. Fred, your world is much different than any I have ever seen. Ed wb6wsn |
"Some Guy" wrote in message ... Dave Bushong wrote: [Dramatic generalization mode on] Nearly all aircraft accidents are caused by a series of unlikely events all happening together, none of which by itself would be a problem. [Dramatic generalization mode off] Nice sweeping piece of dis-information there buddy. Will the in-flight use of an FM radio EVER cause a plane to run out of fuel? Or cause a sudden ice build-up on the wings? Or blow out a tire upon landing? Or an overload of the electrical system leading to a fire? Will the feeble RF emitted by the LO even be detectable OUTSIDE the plane, where the plane's antennas are located? It's so damn complicated that nobody can answer the question. Airliners are going in the direction of all-electronic flight control and management systems. Somebody's LO won't affect fuel consumption, uhh, unless it affects the microprocessor or sensors controlling the engine. It's unlikely, a lot of work goes toward making it extremely unlikely. But remember, I said unlikely, not impossible. Ice on the wings? What controls the de-icing boot? Blow a tire? Is the braking circuit all-mechanical, or do you have something akin to power boost and anti-lock sensing? Is the LO detectable outside the fuselage, near the antennas? YES, damn it, YES. I have measured it, with calibrated field strength meters. Don't give me your damn dumb opinions when I have seen the results myself. And is the LO emission strong enough to degrade or deny a navcom signal. YES or MAYBE or COULD BE. It depends on the passenger's radio, how he holds it, is he next to a window, is the fuselage unusually leaky to RF, what seat is the passenger in, what station is the radio tuned to, are the batteries new or weak, how weak is the navcom signal, what is the attitude of the aircraft, is the navcom receiver getting old, even are there multiple passenger receivers acting on the navcom (if they are all like you, how many of 300 passengers will have personal electronics running?). The POSSIBILITY of interference is undeniable. The PROBABILITY is very difficult to predict. The safe course is to deny you your entertainment for several hours to ensure maximum safety. Is that too much to ask of you? Ed wb6wsn |
"chuck" wrote in message nk.net... Dave, try these: Boeing has investigated alleged interference from portable electronic devices (PEDs) and concluded: "As a result of these and other investigations, Boeing has not been able to find a definite correlation between PEDs and the associated reported airplane anomalies." You can look this up at: http://www.boeing.com/commercial/aer..._textonly.html Aero 10 - Interference from Electronic Devices Here's another one: http://www.rvs.uni-bielefeld.de/publ...ticle/EMI.html Electromagnetic interference with aircraft systems Not to cast aspersions on Boeing research, as they are quite reputable, but if they had found correlatable evidence of PED's interfering with avionics, who gets sued? The passenger, a Hong Kong radio manufacturer, or the aircraft builder? In any case, the reports of interference keep coming in, despite the difficulty of replicating the problem. Obviously, the problem is rare and elusive, but, as in most Electromagnetic Compatibility issues, the easiest, surest, and cheapest cure is to control the source of the problem. Just turn off ALL passenger electronics for the duration of the flight. Read a book for 2 hours, and let your kid kick the seat in front of him. Ed wb6wsn Ed wb6wsn |
"Dave VanHorn" wrote in message ... Well, I'll be flying to philly again tuesday. My dualband HT goes in my breifcase, but with the battery detached during flight. The first note of personal responsibility and common sense yet seen in this thread. Congratulations! Ed wb6wsn |
"Ed Price" wrote:
... Stick to assertions that have a basis in fact and not just in your mind. ... Fred, your world is much different than any I have ever seen. Ed wb6wsn My world is as an instrument rated pilot and one who services aircraft avionics. And you must have missed my other post where I said PEDs should be off at all times. Fred F. |
"phoneguy99" wrote in message .. . TaxSrv wrote: cabin. But has anybody ever heard a cabin announcement during flight to turn off any devices? Fred F. YES. SNIP On one flight, a few years earlier still, WITH the ok from the flight deck (you know, in those friendlier years when you could say 'hi' through the open cockpit door when you were coming out of the bathroom) I used my FT-470 handie for a few mins. The pilot knew what ham radio was, knew I was going to be on UHF (because I told him that's where I would try for a quick QSO) and he very politely said "Sure, but only for 5 minutes, then turn it off. What seat are you in?" I thanked him kindly, returned to my window seat, and did manage to get into some repeater in Maine for about a minute or two. The funny thing was he was in the galley as we were getting off the plane, I thanked him again, and he asked if I had any luck, I said 'yep' and asked him if I came over anything up front. He smiled and said "Nope, and we were up there looking to see if you would." The purpose of my sharing this snippet from many years ago is not to illustrate there's no danger in using a receiver (or in this case, a low power transmitter) while on a plane, but using one does not automatically imply you're going to write off the comm/nav systems. My $.02 It also illustrates the safety concern. Although there were no observed improper responses from the aircraft avionics, "we were up there looking to see if you would" (cause a problem) is very disturbing. You added to the pilots' workload for several minutes, involving them in an interesting science project. The cockpit is normally a very busy place, so what tasks were slighted to allow time for your project? How would you have felt if the flight crew was diverting some of their time to help somebody with a tough crossword puzzle? Was a Maine QSO worth it all? I'd have given you a whole quarter to pull the battery from your HT! Ed wb6wsn |
Years ago I was flying in a friends private plane. I used a Ht on 146.52 to
make some contacts. My friend announces that we are lost. It took about 10 minutes before I found a landmark and got him following a road to the airport. My friend believes that the HT interfered with his radio compass and put use off course. After the HT was turned off and time was allowed, the compass returned to normal. I don't know how it happened, but it did! Now I just carry my ht on the plane and do not operate! Randy ka4nma |
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'Course, he was also a ham and we were flying in a sailplane that had a couple of light bulbs for electronics. [g] The only way to fly. Well, if one of the light bulbs goes out, they'll blame it on the nearest ham :) Seems pretty safe, but I still wouldn't do it without permission. I'm like that when I drive. I'm in the left seat, it's my car and my ass, and I make the decisions. I have actually had a passenger throw a fit because I wouldn't make a left turn that I wasn't convinced was safe, in the 1-2 seconds I had to look at it when the passenger hollered "turn left here". He got to walk home. |
Some Guy wrote:
"I have no trouble receiving FM radio broadcasts on a small am/fm radio I sometimes listen to while onboard commercial jet sirliners (flying at cruise altitude), but I bever seem to be able to pick up AM radio stations. It`s just static across the AM band. Any explanation for this?" Fuselage of the airliner acts as a waveguide below cutoff frequency (where diameter is at least 1/2-wavelength). Below cutoff, attenuation soars rapidly. FM wavelength is about 3 meters. AM wavelength is about 300 meters. Propagation of FM inside the fuselage is OK. Propagation of AM inside the fuselage vanishes quickly. You need to stick the suction cups of your Zenith portable`s Wave Magnet to a window to get AM reception. Best regards, Richard Harrison, KB5WZI |
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