China military: The crash occurred on 2011 China International General Aviation convention air show held in Shaanxi Pucheng Beijing the morning of October 14. A JH-7 Flying Leopard fighter-bomber conducting low-altitude performances did not pull that out of control fell to the ground. Witnessed the scene, the aircraft has an ejection seat ejection success, rear pilot landed safely, but the cockpit for the pilot did not eject. The fighter in the world of the previous crash, the ejection seat has been playing a very important role, perhaps we will ignore the usual presence of the device, just as the pilot of the aircraft sat in the chair only, this equipment actually played the entire life cycle in the plane or not, or only played a second role. Although only one life, but for military aircraft ejection seats for its importance is self-evident.
JH-7 FBC-1 Flying Leopard fighter bomber Crash moment
Always accompanied by numerous flight risk, in a few kilometers to hundreds of kilometers altitude once the aircraft flying out of control, people falling on the ground is certainly a dead end. But the lure of the sky unstoppable, do you want blue sky, overcome self-sacrifice is inevitable, but how can we sacrifice to minimize it? A new discipline came into being, this is the aviation rescue techniques. Air rescue system is to focus the pilot's life-saving issue, set the organization and ejection, survival help, search and rescue equipment, a system as a whole.
In the propeller era, due to lower aircraft speed, so relatively easy to escape, the pilot can open the hatch turned out of his parachute, but also allows the aircraft upside down off a plane flying upside down, but the emergence of these skills is no longer in the jet possible jet, much faster than propeller-driven aircraft, and often in humans can not breathe on their own for more than 10,000 meters altitude flight, strong thin air and air from the machine at any time can kill the pilot.
Jet era aircraft propeller era did not, as has been the pilot climbed out of his parachute, to protect the safety of pilots, but to use the ejection seat, developed in Germany 40 years after the ejection seat, with the development of military aircraft, ejection seat In the past sixty years is not disconnected branching evolution to the initial product with a completely different level. In the first human space travel, the ejection seat has also played a key role, Gagarin is the ejection seat from the spacecraft returned to rely on the ground.
During the accident flight, the aircraft above ground about a hundred meters or so, the success of the ejection seat, and front seat ejection failure, and perhaps some readers will think, now known as the ejection seat is not all "00" ejection (zero altitude, zero speed ejected safely) do?
Zero - zero ejection, the field of contemporary life-saving standards for air, which means that the aircraft is about to fall to the ground state can be allowed to fly away from the machine safe, but the standard is completely reliable in practice? The answer is no. Zero - zero ejection test, is used in process control automation devices ejection test platform to test, not a real machine, but not the real operation, and real operation and control of their own electronic device there is a difference between the nature of man to be ejected hands away from the joystick, move the handle to flip the ejection handle, and handle in order to prevent misuse have some insurance on the device, these operating procedures greatly improve the operation of reaction time. And electronic devices, just only need to give a start pulse signal can be a catapult, practice takes no more than hundredths of a second, there is no comparable responsiveness.
And quite critically, the ejection is the need of people to respond, when the aircraft at low altitude in tens of meters out of control, how to deal with the next step? Is ejected or the need to save the aircraft pilot to judge the first time, and this time even if only 0.1 seconds making enough to catapult him to lose the opportunity. This time of the accident point of view, the first time in the pilot ejection seat, which is not done with its last-ditch effort to save the aircraft on the front seat pilot is likely to have been trying to level the aircraft in order to save the aircraft, so missed the best time to ejection. If there is no chance of rescue, that the pilot will determine their own more quickly, but can increase the probability of rescue. The earliest catapult, using high-pressure air or gunpowder bomb ejection, but as technology development, countries are invariably used rocket ejection seat. And high-pressure air or gunpowder bombs compared to small changes in the output thrust of the rocket launch, unlike the other at the beginning of the ejection phase there is a huge acceleration can damage the spine pilots, and plenty of thrust lasting wear cover in case the power is greater, while As the rocket engine can continue to work higher altitude the pilot ejected, so the pilot is not easy to be out of control of the aircraft tail and wings are linked to, greatly improves the efficiency of flight safety.
For aircraft ejection hatch is a huge obstacle in the ejection speed must be the fastest and most efficient to open the ejection channel, which is also the focus of research. Early use of disposable cover type ejection seat ejection means, mechanical parts will be stripped cockpit hatch, but after all the weight of large mechanical systems, the reaction is slow and requires a complete high-pressure hydraulic or air systems, because the aircraft are generally out of control ejection state, the aircraft's main hydraulic system and the main high-pressure air has lost most of the time performance, it is necessary for the ejection seat to install a separate system, so greatly increased complexity and reduce system reliability. In the 1960s, began blasting systems, blast the soft cover cable installed in the cockpit, ejection, when an explosion detonated by an electrical ignition device cable exploded hatch. 70's, wearing a cover system into the mainstream, relying on power catapult itself, with the top of the fork cap to wear direct violence broke open canopy, wearing a cap fork is a metal structure fixed the reliability problem does not exist, all the rest of the ejection seat chair body needs at any time, this design is the simplest structure, the most reliable solution. But in the late 1970s began to appear monolithic polycarbonate bubble hatch, hatch in order to meet the strength requirements of this thick and hard, wear covered through the program difficult to achieve reliable, so a considerable part of three generations of fighter aircraft with a rocket or gunpowder throw cover ejection mode.
The most famous contemporary Russian ejection seat main type of Zvezda K-36D ejection seat, model belonging to the third generation of the ejection seat, the main feature is the use of a speed sensor (electronic / mechanical), according to the response from the machine different flight speeds, different life-saving rescue mode program execution, thus reducing the low-speed parachute rescue parachute time, increased life-saving under a negative attitude success rate.
K-36 ejection seat for the series of the mid-1960s developed the third generation of ejection seats, has produced more than 12,000 units, and the formation of the CIS countries of universal series seats, it features a high-speed stability and performance . According to Russian sources, however, at an altitude of 1,000 meters, equivalent airspeed of 1350 km / h under the conditions of the success of the pilot still emergency ejection. Especially during the Paris Air Show in 1989, a seat equipped with a K-36 MiG-29 aircraft for maneuvering flight performances, due to engine failure caused the aircraft stall, in extremely adverse conditions, the success of the pilot emergency ejection , rescued, so that K-36 series of life-saving devices became famous.
The early 1990s, the Russian star in K-36 consortium developed based on a K-36Д-3.5 ejection seat. This level of ejection seat flight performance envelope and the K-36 series of the same seat, and in the unfavorable conditions of life-saving gesture performance has been greatly improved. For example, aircraft flight speed of 278 km / h, inverted the minimum safe altitude of 95 meters from the original reduction to 46 meters. Main improvements are: the use of EPC technology, controllable thrust technology, rocket engine technology inverted cut, roll attitude control technology, the K-36Д-3.5 initially with the fourth generation ejection seat some of the features, has installed capacity of service (such as Su-30, Su-37), and JSF aircraft in the United States bid. Paris Air Show 1999 Su-30 fighter jets led to the most will wipe the seat height in near-zero to save the lives of two pilots. The seat design is attention to detail, installing a retractable stabilizer bar, making the air attitude stability; has contracted with a design, when the ejection force pilot and limbs tightly tied close to the body, reducing the pilot area of the body, so it does not agreed to be hook injury.
The development of China's ejection seat through a scratch, from weak to strong development, was first in the Soviet MiG-15 fighters to receive to obtain the first ejection seat, from imitation to go on the basis of self-developed over the course of six years. Early on, China's ejection seat ejection widespread poor reliability, greater damage to the pilots, especially the early J-7 fighter aircraft ejection using the program even with the hatch, the loss rate is very high accident; H-6 bombers The ejection seat is cumbersome and unreliable, many times the plane crash tragedy. In the last three decades, with experience, catapult performance has also been rising, this time in the HYT-6BB accident ejection seat performance series on the more reliable, this type of catapult built using gunpowder thrown way, with the type QKS-14 two-state controller, according to a different flight speed ejection time, to determine the different people / chair separation time, the HTY-6 rocket ejection seat has a good safety profile of adverse life-saving low-altitude capability, under unfavorable attitude life-saving safety envelope. And this model is not the best of our current ejection seat, designed for the J -10 HTY-5 ejection seat restraint techniques and the use of a limb extravehicular stable system performance close to the K-36 series, and for the J-11 series developed HTY-8 with the ejection seat is difficult to explain K-36 Road Series with unknown kinship. Flight accidents in recent years, the majority of cases, the pilots landed safely, but basically because of the ejection failure at the time the pilot has lost the ability to judge, can not be ejected.
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