here is lyanne melendez on the change and what it could mean for passengers. >> this is a control tower at oakland international where the flow of air traffic is constantly being monitored. acting director wants to redesign the aviation cities to be more in line with 21st century technology. >> system we have is a radar based system. radar based system technology from the last century. it gives us a safe and good view of what is happening in the system, but it is not as precise as the satellite base systems that exist today. >> he says it's more precise so the flight plan ends up being more direct. he and other aviation partners announced the faa's metro plex initiative which will include sfo, san jose international and the sacramento airport. >> this is about saving gas. from a standpoint from the carrier but what else -- reduced emissions. >> air carriers spend 40% of their boujt fuel. they say if they lower that cost passengers will feel reduced fares. >> if you lower the costs of the provided service you can pass it on. >> so passengers are skeptical. >> i think they'll find ways to

lyanne melendez talked with other people about the celebrations over the years including a woman thatost on the bridge when it opened 75 years ago. >> she took this video 25 years ago. she remembers getting on the bridge at 5:00 in the morning for the 50th anniversary celebration. there was so many people on the golden gate it flat and and the crowd was order off the bridge. >> i remember being really excited. i don't remember it being scary but the only thing i robe is people saying it's moving. >> there were people with crazy hats and a man trying to crosses a bridge on a pogo stick. he was only four years old. >> walking on the sidewalk is one thing but walking across the bridge with marching bands going by, i'm glad they it was awesome. >> there will be no bridge walk. >> the bridge opened in 1937, barbara was only 7 years old, little did she know she would make news that day day. >> got lost. [ laughter ] >> that is in the local newspaper, fourth from the left. along with few other kids that got lost in the crowd that day. campbell is 82 years old and living in burlingame. she re

here is lyanne melendez. >> in a month the former sf bart building will be busy with employees. a thousand will occupy three floors in this building. twitter's sfo gave a tour of the new dig autos being right on market street is both location and it's scale are both terrific. we love being close to city hall. and there is the beauty of the dome. >> miles of cable being put in for those rooms wop tables to hook up lap tops. this is the cafeteria. they like to call it the common. there is a large space with a view of the city will be a favorite of many. twitter's move is expected to revitalize the area. a man presented by mayor ed lee and endorsed by the board of supervisors. and by relocating twitter will receive a tax exemption for six years. >> they've reminded us that but for that exemption and our signaling to them we're going to make an effort on redoing payroll tax i don't think they would have had confidence to stay here. >> there is another firm taking advantage of the deal n recent weeks other tech companies announced they will not only stay in san francisco, but expand.