Re: Dr. Clayton Forrester's Science Roundup
Looking at the image, I was initially shocked that the aircraft (and pilot) could deal with such a drastic change in wing geometry and weight distribution. But, I guess, it's not that different than suddenly "losing" a missile from underneath a wing.
Are you asking, or just making conversation?
First, if the right wing "only" lost 6 feet, then by my estimate it really only lost about 12.5% of the total wing planform (due to the wing taper). It's fun to say that it lost "half a wing" but it's not accurate, and every square foot counts. If the aircraft was lightly loaded (i.e. no air-to-ground weapons, partial load of fuel), then the aircraft was probably at less than half of its max gross weight - clearly plenty of wing area left to keep the plane aloft.
The article makes one other common mistake: yes, the F-16 is slightly unstable, and yes, it has a "fly-by-wire" system to compensate for that, but in the case of the F-16 (and most other fly-by-wire aircraft*), the wires are just sending the control signals to the actuators, which still use hydraulic pressure from a redundant centralized hydraulic system to provide the "muscle" to move the control surfaces. Each of the two hydraulic systems is plumbed to each actuator, so if a single hydraulic system is lost, the other can still fly the jet. In this case, where the actuator for the aileron itself was ripped off the aircraft, there is no question that both hydraulic systems were severed, so a key feature which allowed the pilot to land are the "hydraulic fuses" in each system. As soon as a branch of the system breaks, the flowrate goes through the roof, the fuse detects that (mechanically), and automatically closes before all the fluid is lost - exactly analogous to a circuit breaker in an electrical system which shuts off the power to the circuit if the current goes too high.
*some small or low speed aircraft use electro-mechanical actuators (EMAs) to directly move the control surfaces using electric power, but nothing having remotely close to the extreme control surface loads of a fighter jet, and those aircraft are generally not fly-by-wire because they are not unstable. The F-35 (unstable) and the 787 (stable) come the closest to "power by wire," but in the case of the F-35, electric power goes out to each actuator where there is a small electric hydraulic pump which provides enough flow to move that one actuator's piston. The 787 is similar, but it uses a few "localized" electric hydraulic pumps which provide flow to multiple hydraulic actuators that are close by - the power is sent over the long distances via electricity, and then locally by hydraulic flow. The weight savings of replacing the long-distance hydraulic tubing with electric wiring more than makes up for the extra power conversion losses.
Looking at the image, I was initially shocked that the aircraft (and pilot) could deal with such a drastic change in wing geometry and weight distribution. But, I guess, it's not that different than suddenly "losing" a missile from underneath a wing.
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