tonight on "nightline" -- the hunt for a plane with 239 on board. disappearing mid-air without warning. what was the cause? pilot error? mechanical failure? an act of terror? a two-year "nightline" investigation into the last mysterious disappearance and clues that might help unravel the mystery at 35,000 feet. plus, ban bossy. why celebrities from beyonce -- >> i'm not bossy. i'm the boss. >> -- to jennifer garner. >> being labeled something matters. >> are joining facebook's sheryl sandberg to ban the schoolyard taunt. the surprising power of the other b word. does it really keep women down?

and prince charming. are things getting serious with this girl? stepping out in public for the first time. and then doing it again. what bookies are predicting for harry. >> announcer: keep it right here, america. "nightline" is back in just 60 seconds.

at kaiser permanente we've reduced serious heart attacks by 62%, which makes days with grandpa jack 100% more possible. join us at kp.org and thrive. good evening. malaysian authorities say they haven't found a trace of the 11-year-old boeing 777 that disappeared over three days ago. now troubling questions are emerging. how did two passengers board the aircraft with stolen passports? why did five passengers fail to board at all after they checked in? abc's elizabeth vargas spent two years on a "nightline" investigation into an earlier

catastrophic crash with eerie similarities. could that tragedy shed some light on this one? >> reporter: more than 72 hours after malaysia airlines 370 simply vanished from r5idar screens the mystery is only growing. how did the beijing-bound six-hour flight from kuala lumpur simply disappear around 40 minutes in, along with 227 passengers and 12 crew members on board? >> we're unable to determine the cause or the causes of this incident. >> most likely it went in the water. most likely it went in intact. and most likely we are going to find the wreckage in the next few days. >> reporter: and while it may seem unprecedented for a modern jet full of passengers to simply vanish mid-flight, it has happened before. most recently in 2009. what happened to that jumbo jet remained a mystery for more than two years. it is may 31st, 2009. air france flight 447 prepares

to depart rio de janeiro. 7:30 p.m., takeoff. it is a routine 11-hour flight across the atlantic. the plane is filled with vacationers, businessmen, and families. destination? paris. 8:30 p.m., passengers settle in. there is no sign that one of the biggest mysteries in modern aviation is about to unfold. the airbus a-330, like boeing's 777 in last weekend's crash, has a strong safety record. >> airbus is proud of the fact, they like to say, that their plane is pilotproof. >> reporter: that's the good news. here is the bad news. is it true that on any given flight the pilots are at the controls only three minutes? >> yes. >> a minute 30 on takeoff and a minute 30 on landing? >> that's about right. >> reporter: it's a cold fact of modern aviation. planes pretty much fly themselves. while it's not known what

happened to malaysia airlines 370, the story of flight 447 ignited a firestorm of controversy about pilot training in this new era of automated flight. >> we're moving towards automated operations where the pilot isn't even permitted to fly. >> because of this sophistication and the ability of airplanes to fly themselves, they don't have as much opportunity to actually fly the airplane. >> reporter: that would have fatal consequences for the final flight of air france 447. at 10:00 p.m. it is still business as usual on that flight. the crew serves dinner. and some passengers watch an in-flight movie. but 30 minutes later the plane cruising at 37,000 feet begins to enter a heavy storm system. at the same time the location of the storm happens to coincide with a known dead zone of radio communication. out of reach of air traffic controllers on either side of the atlantic. 10:5:00 p.3 10:35 p.m. the last radio

transmission from air france flight 447. sometime in the next six hours the airplane would crash into the atlantic soegs. >> the captain is sitting where i'm sitting right now. >> storm on the left side. >> reporter: in 2012 bill voss, then of the flight safety foundation, joined us in an a-330 flight simulator to recreate what happened in the final crucial moments. >> the autopilot disconnects. >> the autopilot disconnects. >> reporter: we know from cockpit voice recorders that the captain stepped out to take a break when the autopilot suddenly switched off after ice crystals formed on the sensitive tubes on the airplane's wings. >> there's a warning. the aircraft is now in my control. >> he should have just kept the plane flying. he shouldn't have changed anything. but instead what did he do? he pulled the nose of the plane up? >> a fairly dramatic pitch-up. >> reporter: raising the nose of the plane is precisely the wrong thing to do. it can essentially cause the airplane to start falling out of the sky.

it is the most baffling and disastrous minute of the flight. soon the plane's stall warning goes off. >> stall, stall. [ alarm ] >> reporter: but no one seems to pay any attention. >> stall, stall. >> it actually sounded for a total of 54 seconds, which is a lot of time. >> reporter: as the stall gets worse the plane becomes harder to fly. on the black box recordings bo investment n says "i don't have control of the airplane at all." the co-pilot is calling for the captain. where is he he asks at one point. when captain dubois does enter the cockpit he finds a scene of utter chaos. >> the pilot did not understand the situation and they were not aware that it had stalled. >> reporter: within seconds the plane has entered such a deep stall it is plummeting at 120 miles per hour in the dark, belly first. >> stall, stall. >> reporter: i got the chance to experience what that felt like in the airbus simulator. >> stall, stall. >> now we're going down, right?

>> yes. >> reporter: meanwhile, in the cockpit, confusion has turned to chaos. both co-pilots are now trying to fly the plane in opposite directions. >> at what point was this jumbo jet beyond saving? >> somewhere in the area of 10,000 to 15,000 feet they were really running out of options. >> reporter: it is too late. but it is not until the final seconds that the pilots realize the plane is doomed. >> and the very last words we hear on the cockpit voice recorder are from the pilot bonin, who says, "but what's happening?" >> exactly. just complete confusion. >> reporter: it takes hours for french air traffic control to realize something is wrong. >> your attention, please. >> reporter: by now friends and family of the passengers are already waiting in the arrivals terminal in paris, when word begins to spread. flight 447 has simply disappeared. a scene devastatingly similar to the one that played out in beijing early saturday morning.

nearly three dozen aircraft and 40 ships from ten different countries are now combing the gulf of thailand, looking for clues. back in 2009 it took crews five days to begin finding the first pieces of wreckage from the air france flight. french investigators went on to invest two years and $50 million trying to find the rest of the airplane, without luck. so they called in mike purcell and his team. the same team that famously found the titanic. not only did purcell's team find the black boxes in the wreckage, after two years in the water they still worked. today in woods hole purcell told us about the similarities and the differences between the searches for the two airplanes. >> there are some similarities. people want to know why it happened. i think that the location of this crash is a little bit different from the air france one. so once the underwater search starts i think that it will be pretty easy to find it. >> reporter: the final investigation report concluded that the mechanical error was

mishandled and misunderstood by the pilots, who in turn caused the plane to crash by their actions. some lessons for this investigation, as details begin to emerge. but first they must answer the biggest mystery so far. where is the airplane? for "nightline" i'm elizabeth vargas in new york. >> mm. some eerie similarities. although the two incidents did involve different types of planes as well as different weather conditions. up next, the word celebrities like beyonce want to ban. [announcer] if your dog can dream it, purina pro plan can help him achieve it. ♪ driving rock/metal music stops ♪music resumes music stops ♪music resumes

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facebook's sheryl sandberg changed the conversation about women in the workplace with her best-selling book "lean in" which came out exactly a year ago. and now she's launching a new public service campaign to ban the word "bossy." why? because she says it's a big part

of the reason so few women make it to leadership positions. and there is some research that backs her up. we sat down at facebook headquarters in menlo park to talk about the other b word. >> when i was growing up, i was called bossy. >> reporter: sheryl sandberg, facebook's c.o.o. and newly minted billionaire, has launched a campaign today to ban a surprisingly powerful word. >> bossy. >> bossy. >> bossy. >> bossy. >> reporter: and she's pulled together a group of celebrity friends to help her pull it off. >> ban "bossy." >> this is the other b word. we call girls bossy on the playground. we then call them too aggressive or other b words in the workplace. >> reporter: for the past year she's traveled the world discussion her best-selling book, "lean in," encouraging women to embrace leadership. >> what we know is that stereotypes are holding women back from leadership roles all over the world. >> reporter: she argues those negative stereotypes get a big boost from the use of the word

"bossy." >> i've asked audiences all over the world, and this is what women face. they're bossy as little girls, and then they're aggressive, political, shrill, too ambitious as women. >> can i just say? i was called bossy. were you called bossy? >> i was called bossy. when i was in ninth grade, my teacher took my best friend mindy aside and she said, you shouldn't be friends with sheryl, she's bossy. and that hurt. we know that by middle school more boys than girls want to lead. and if you ask girls why they don't want to lead, whether it's the school project all the way on to running for office, they don't want to be called bossy and they don't want to be disliked. >> reporter: we decided to put that to the test. we asked dr. harold koplowitz, a highly respected child psychologist, to join us in the conversation with first graders at the hunter school in new york city. >> if i said to you you're bossy, does that make you feel good or bad? >> bad. because you don't want to be bossing people around. because it just means they tell people what to do. >> they feel like no one will

like them if they're bossy. >> if someone did call you bossy, you would just -- you should probably say sorry. >> raise your hand if anyone's ever called you bossy. a lot of hands up. so what's more important? to be liked or to be a leader? >> to be liked. >> to be liked. >> if you're a leader, your friends will get mad at you and they won't want to be your friend anymore. >> what i'm concerned about is that the girls were ready to throw leadership out the door for friendship. >> this is exactly what sheryl sandberg says, though, is girls -- and by the time they're in junior high school are completely willing to say, you know, i'm not raising my hand, i'm not going to be the leader. >> so i would tell you that i don't think it's junior high school. i think it's just the progression that starts now and junior high school makes it or middle school makes it worse because there's hormonal changes that only gets exaggerated when you get to that point.

>> reporter: in fact, research shows a direct link. a third of the girls who don't want to be leaders say it's because they fear being called bossy or being disliked by their peers. >> if you look at the world, women do 66% of the work in the world. women produce 50% of the food. women make 10% of the income. and women own 1% of the property. in every country in the world women are 5% of the top company ceos. we live in a world that is overwhelmingly run and owned by men. if you paid women as much as men, you would cut the poverty rate for this nation's children in half. >> so you really think you can change 77 cents on a dollar by banning "bossy"? >> we think it all goes together. >> that's good. >> reporter: she's recruited former secretary of state condoleezza rice and girl scout ceo anna maria chavez to the "ban bossy" campaign. appearing together yesterday on the cover of "parade" magazine. >> how did you do get together? how did this happen?

is that true? you didn't know each other. >> i called her. i said hi, i'm sheryl, i started lean in, i want to -- i was a girl scout. i want to talk to you about doing something together on girls' leadership. you have by far the best leadership programs out there in the world at scale for girls. >> it made sense. that's what girl scouts has been doing for 101 years, talking to adults about investing in girls and supporting girl leadership in this country. i love the opportunity to partner with her and lean in, to share this message in a very relevant way, that investing in a girl is a really good thing to do. >> if women are called ambitious, it means something totally different than when men are called -- >> it's negative. it's amazing. hillary clinton runs for president and they say she's too ambitious. she's running for president. of course she's ambitious. >> reporter: but all this is hard even for sandberg. when "forbes" named her the sixth most powerful woman in the world, she was embarrassed. >> they would say congratulations, you're on this most powerful women's list. and i kept saying shh. my friends would post it on

facebook and i would call them and say can you take that down? and my assistant said you're handling this terribly, you're not handling this well. say thank you. but that story gets to the root of what being bossy tries to address, which is leadership, accomplishment, ambition. those are positive for men. they're often negative for women. >> and that even you -- >> even me. i wrote a whole book talking about how i still struggle with this today. >> it would be easy for it to be misunderstood and have people hearing you say that it's okay to be a mean girl. that's not what you're saying. >> leadership is not bullying. and leadership is not aggression. leadership is the expectation that you can use your voice for good, you can make the world a better place. often it's other little girls calling little girls bossy. this isn't as simple as one word. and this shouldn't be trivialized as a word. this is a word that is symbolic of systematic discouraging of girls to lead. >> reporter: while it didn't hold sandberg back, she says it's what makes so many other women opt out. she credits her parents with

giving her the courage to lead. >> i never thought of sheryl as bossy. >> you didn't? >> no. she's the oldest child. she helped me take care of her younger brother and her younger sister. so i never thought of this as bossy. i was shocked when people called her bossy. >> i tell parents, don't call your little girl bossy. instead say my daughter has executive leadership skills. that sentence is funny. now let's try it for a boy. my son has executive leadership skills. no humor. that difference shows you how set our expectations are. men leading, boys leading is expected. girls leading has humor or is negative. that's what "ban bossy" is going to change. >> i'm not bossy. i'm the boss. >> a final note. sandberg is on the board of the disney company, the parent company of abc news. for more on the "ban bossy" campaign visit abcnews.com/nightline.

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he's trekked to the south pole, run with olympian usain bolt, and flown apache helicopters. but is the world's most eligible bachelor ready for another trip? maybe down the aisle? after nearly two years of dating prince harry and his girlfriend cressida bonas attended their first ever public event together on friday, when harry spoke to a group of 12,000 students and showed that even a prince can be self-deprecating. >> for those of you who were expecting harry styles, i apologize. and no, i'm not going to sing. >> reporter: two days later the pair chatted throughout a rugby game during their second public outing. bookies are now predicting a royal engagement within the year. we shall see. tomorrow on "nightline" my

co-anchor dan harris shares a very personal story. ten years ago he had a panic attack on live television. >> may also lower their risk for cancer. but it's too early to prescribe statins for cancer production. >> reporter: and it led to a strange and sometimes hilarious odyssey. >> you never wake up thinking i can't believe i'm getting away with this? >> reporter: join us for how the answers he found could change your life and maybe make you 10% happier. tomorrow on "nightline." >> thank you for watching abc news. tune in to "good ♪ they lived. ♪ they lived. ♪ they lived. ♪ (dad) we lived... thanks to our subaru. ♪

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