GS_Dirtboy
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This was an obvious stall on take-off. Aircraft need air moving smoothly over the wings to provide lift. Wings (viewed from the end) are curved on top and flat on the bottom. When the aircraft is moving forward two points of air meet the leading edge of the wing and they separate. One point goes below and one point goes above. These two points of air must reach the trailing edge of the wing at the same time. Because of this, the point of air that travels over the top surface must go faster (more distance, same time). Now think of these two points of air as air mass. The mass of air on top of the wing must cover a larger surface and must "stretch" to do this. This creates "less" air mass per square inch on top than on the bottom. This creates a low-pressure area on top and a high-pressure area underneath. The resulting pressure differential is what lifts the aircraft off of the ground. If you've ever been in a commercial airliner you might have noticed the wing tips bending upwards just before take-off. This is the lift I'm referring to.
Technically, an aircraft can stall at any air speed if the boundry layer air breaks away from the wing surface. This can happen because the airspeed is too slow, because of interference of the moving air by snow, ice and other surface debris, or by simply forcibly breaking the boundry layer away from the wing surface with high g's as might happen in air combat.
In this video, the 747's nose is extremely high. It also "appears" that the forward speed of the aircraft almost comes to a stop. However, that's a visual error created by the video and perspective of the aircraft. In actuality, the takeoff speed for a 747 is probably 200 knots or so. Think 240 mph. That means stall speed is in the area of 150 knots which is the speed at which the wings rocked left, then the right wing dropped and the nose came down.
There were some reports that the pilot radioed that the load of armored vehicles had slid to the rear of the aircraft on take off. If this is true then that weight towards the back would push the nose up with such force that the pilot would not have sufficient control to bring it back down, resulting in the stall you see on the video.
The Loadmaster is responsible for making sure that cargo is secured. He, or she, would have been part of the crew on the aircraft. The loadmaster might have done everything correctly. Sometimes sh*t just happens.
The following video is the military jet version of the 747 crash, though this happened on landing. This pilot of this aircraft, Steve Pontrel, was in the flight school class ahead of me at Pensacola. He got low in approach to the ship, was waived off, pulled the nose up and stalled. he was a good pilot. We were clueless at to what could have happened. Some people suggested he might have had some event like a hear attack or passed out, but you can clearly see the ejection sequence happening as the aircraft rolls into the ships superstructure. It was later determined that the cables connecting the power levers to the power control unit on engine 1 were installed backwards and a cable junction got caught on the inside of the air frame preventing him from applying full power on that engine.
Technically, an aircraft can stall at any air speed if the boundry layer air breaks away from the wing surface. This can happen because the airspeed is too slow, because of interference of the moving air by snow, ice and other surface debris, or by simply forcibly breaking the boundry layer away from the wing surface with high g's as might happen in air combat.
In this video, the 747's nose is extremely high. It also "appears" that the forward speed of the aircraft almost comes to a stop. However, that's a visual error created by the video and perspective of the aircraft. In actuality, the takeoff speed for a 747 is probably 200 knots or so. Think 240 mph. That means stall speed is in the area of 150 knots which is the speed at which the wings rocked left, then the right wing dropped and the nose came down.
There were some reports that the pilot radioed that the load of armored vehicles had slid to the rear of the aircraft on take off. If this is true then that weight towards the back would push the nose up with such force that the pilot would not have sufficient control to bring it back down, resulting in the stall you see on the video.
The Loadmaster is responsible for making sure that cargo is secured. He, or she, would have been part of the crew on the aircraft. The loadmaster might have done everything correctly. Sometimes sh*t just happens.
The following video is the military jet version of the 747 crash, though this happened on landing. This pilot of this aircraft, Steve Pontrel, was in the flight school class ahead of me at Pensacola. He got low in approach to the ship, was waived off, pulled the nose up and stalled. he was a good pilot. We were clueless at to what could have happened. Some people suggested he might have had some event like a hear attack or passed out, but you can clearly see the ejection sequence happening as the aircraft rolls into the ships superstructure. It was later determined that the cables connecting the power levers to the power control unit on engine 1 were installed backwards and a cable junction got caught on the inside of the air frame preventing him from applying full power on that engine.
