first though the technology that it takes to find the black boxes, miguel marquez has that story. reporter: the search for air asha 8501. a pings from the flight data recorder. a pinger has a specific pulse. it comes at a specific interval and frequency. correct. but still hard to find. yes, it is. reporter: forensic audio expert paul ginsburg shows what it would sound like with any competing sounds. but said there is plenty keeping for attention at the bottom of the sea. a school of fish swimming currents. echoes from the signal bouncing off different rock formations at the bottom. reporter: this signal he said is what an experienced
get a hold of 77 by chance? reporter: on 9/11 64 people died on board american flight 77 when it slammed into the pentagon. fire crews spent days trying to put out the flames. the two black boxes were found in the wreckage but the cockpit voice recorder was too charred to offer anything of value. it flew in with such force and the fire was so intense, that nothing could have survived that impact. reporter: indonesian officials say they hope to recover the black boxes of air flight 8501 within a week hoping this discovery gives them the crucial information they need to figure out exactly what happened. randi kaye cnn, new york. let s talk about this with our panel. david soucie and david gallo. we talked about the weather. obviously, that is a problem in and of itself but there are also other problems with the search going on including the
attendant. her and others took off on sunday, of course. 132 men, women, and children remain unaccounted for. they at some point, will begin the same quiet journey we witnessed today. a military honor guard shouldering the caskets, loading them on aircraft that carried them out of the search zone and back to sarabuya. a process likely to be repeated again and again in the days ahead. david malko joins us. day five of the search has begun there. how s the weather, what s the latest? reporter: hi jake. very active search effort at this moment. the u.s. sampson recovered human remains out again with some 40
but it took putting the plane back together all two million pieces of it to figure that out. bottom line the so-called black boxes aren t perfect. and they re not black either. they re usually orange. on an airplane they re tucked inside an insulated case and surrounded by stainless steel. they re built to withstand temperatures as high as 2,000 degrees fahrenheit and catastrophic impact. after twa flight 800 went down in july 1996 just 12 minutes after takeoff from new york s jfk airport, the plane s black boxes were recovered but they offered little. both the voice recorder and the data recorder terminated their operation within a nanosecond of each other. when the explosion took place. reporter: still, despite all the conspiracy theories, investigators say they figured out an explosion in the fuel tank caused the crash and shut down the recorders. indianapolis center did you
operator might initially hear. just as when you re listening to a radio station that s out of your range. reporter: he said because the pings come at regular intervals and known frequency, once have it, the experienced audio technician can clean it up to hear this. we asked ginsburg to show how it s done. a tone with an annoying tone playing. reporter: when he hears it back this is what he works with. in this case i will attempt to get rid of the tone. reporter: analyzes the tone and using his own software is able to zero in on it and remove the excess noise. in this case i will attempt to get rid of this tone. reporter: this job, easy and knew what it was and where it was coming from cutting through the many noises and distortions