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This is the story of United Airlines flight 1722. Hawaii is a US state like no other, its the only state that is made up of islands. This means that getting the to the state requires you to either get on a boat or on a plane and lets be honest most people are gonna be flying. This means that the tiny airport of Kahului and honolulu handles a ton of traffic. On the 18th of december one of those planes was a united airlines boeing 777 with 271 people on board. The jet was to make the trip from kahuli airport to sanfranciso airport. This was one of the many flights that connected the islands back to the mainland. The pilots of flight 1722 were on the ground at Kahului and they punched in the data into their flight computers. This computer would then spit out how to fly the takeoff. It would tell them how much power to use, how long the takeoff run will be all that sort of stuff. Contrary to popular belief you dont go full power for all takeoffs, that would tax the engines too much reducing their lifespan by a lot. So instead youd give the computer the conditions that were expected at the time and youd get an optimized departure profile. ON the 18th their calculations showed that they could get away with a reduced thrust takeoff with flaps at 20. But as the plane started to taxi the controller threw a wrench into that idea. You see the sensors around the airport had picked up wind shear around the airport. Wind shear is a weather phenomenon when the direction of the wind quickly changes for a short period of time. Think of it like a current of air that can push planes off course or worse if it is strong enough. This is why modern jets are equipped with wind shear detectors. This information changed their plans the captain now decided to go for a maximum thrust takeoff with the flaps at 20. This would allow them to punch through the windshear with no problem at all, as jeremy clarkson says “power and speed solved many things” and indeed this was one of those cases. So with their new plan the pilots taxied the 777 all the way to the threshold of runway 02 at the airport. The nigh was rainy and dark and the pilots couldn't see very far out into the night. The departure would take them out over the dark pacific ocean and so they would have to keep an eye on their instruments as they flew out to figure out what their plane was doing. With that the pilots lined the jet up with the runway the lights of the runway shone through the rainy dark night leading them into the dark pacific. The the captain pushed the engines to max power and then engaged the autothrottle. The computer would now take care of the power setting while the captain hand flew the plane on departure. The 777 went though 80 knots and everything was fine and then came the V1 speed. At this point they were committed to this takeoff. With that flight 1722 lifted off into the dark sky. The jet gained altitude as it left hawaii behind. Then right on cue the planes airspeed indicators began to fluctuate as the jet punched through some turbulence. This is what the controller had warned the pilots about when they were on the ground. As the plane picked up speed the the captain called for flaps 5, they were flying fast enough that the plane could have enough lift on its own without the flaps being at 20. The first officer carried out what the captain had asked of him and then he contacted departure to discuss the weather. But the captain noticed something strange. The max speed on the primary flight display was lower than expected. On the primary flight display you have this speed ribbon and on the ribbon you have this red overlay that shows you the maximum speed that your plane is capable of in the current configuration that it is in. its a very simple idea, stay out of the red and you'll be fine. For what ever reason that red bar was lower than expected. He expected to be able to fly a lot faster with the flaps at 5. Then, the plane started to pick up speed. The captain grabbed the throttles and pulled them back to avoid overspeeding thus overriding the autothrottle. He quickly scanned the instruments to see what was wrong with this jet, he saw that the flaps were at 15 and not 5 like he had asked. So he asked for flaps 5 again and this time he made sure that the flaps were now in the 5 degree detent. The first officer was also now trying to troubleshoot the issue. He knew that the captain had some issues with airspeed control and so he asked the captain if his instruments, the one on th