a couple of cities, major cities and there were some towns and villages. is it possible those signals could have got ton a cell phone tower? >> again, if people were awake, trying to use their phone and they were flying that low, it is certainly possible they got to that tower. however, it's also possibly they weren't arable to officially communica communicate. it's not just sending the radio waves, we have to actually be in touch long enough to have a little conversation. >> those onboard were able to have conversations because the planes were flying very low in density populated areas when their calls were received. but experts say most of those calls were not made from cell phones. but airline phones which use radio or satellite technology. a technology that has been phased out for the most part because of its high cost. but malaysia flight 370 did have air phones in business class. they might have been deliberately disabled along with the transponder and other communication systems. but cnn aviation am linalyst ma