Spread your wings and fly in Tianmen Mountain: Why doesn't An An open his parachute?

Flying in Tianmen Mountain Wing: Why doesn't An An fly a parachute? Ann didn't open the parachute because it was obvious that the airflow was beyond Ann's control. Skydiving must have a safe opening height, below which he will die or be seriously injured because he can't open the umbrella. In the end, Ann probably chose to reach the other side of Tianmen Mountain from a low place, but it didn't succeed.

An An, a female college student who lost contact in the flight of Tianmen Mountain wing suit, was found falling into the forest, and her parachute did not open. Unfortunately, the miracle did not happen. Unfortunately, friends who know about wing flight should also know that skydiving can ensure safety in most cases. Then why didn't Ann skydive?

Flying with wings, as the name implies, is to put on aerodynamic clothes and slide, and then slide quickly in the airflow, which looks cool. Compared with the weight of human body, the aerodynamic lift area of wing is very low. There are wing loading requirements in fighter design, that is, wing area and takeoff weight must meet the requirements. Of course, flight speed also has a lot to do with it. The bigger the wing loading is, the greater the flying speed is needed to generate enough lift!

But the wing is gliding, and there is no engine at all, so its speed is provided by the descending speed. According to the aerodynamic performance of the wing, its gliding ratio is about 2.5-3: 1, that is to say, how small is this gliding for every drop 1m and 2.5-3m forward? This is the dirtiest glider with a gliding ratio of 20: 1. Advanced gliders can even reach 50: 1, with high speed, large wing loading and low gliding ratio, which leads to two results: extremely low controllability and inability to land on its own.

Controllability refers to the ability of an aircraft to avoid obstacles in the air and maneuver through the control surface. Due to the high wing loading, it is necessary to react in time when avoiding obstacles, so as to avoid timely maneuvering. So when flying in the canyon, especially when encountering airflow, the risk is great! The other is installed on the wing, and its gliding speed exceeds 250 kilometers, even higher than the take-off speed of fighter planes. The human body cannot accept this impact landing. So the final stage of wing flight is to open the parachute and jump at a fixed point. Therefore, winged flight should not only be able to fly, but also receive strict skydiving training.

After understanding the necessity of skydiving, let's make a simple analysis. Ann, why don't you jump! According to public reports, if a parachute helicopter flies at an altitude of about 2500 meters, the maximum distance it can fly by gliding is about 6.25-7.5 kilometers, but this is the data of barrier-free flight, and there is no updraft. If there is interference between them, the flight distance may change.

As we can see from the camera, Ann and the photographer jumped out and left soon after. In fact, there is nothing wrong with this operation, because it is dangerous to be too close, but we can see from the lens that An An is not keeping a certain distance, but changing the direction and distance quickly. There are two possibilities. Photographers may be experienced and can feel the airflow and adjust their direction quickly, but An An may not be able to adjust back in time!

This may not be a big problem in the open area, but this mission is to cross Tianmen Mountain. The towering Tianmen Mountain is only a few kilometers away from where they jumped off the helicopter, so An An may not be able to cross the height of Tianmen Mountain when she changes direction, so the photographer motioned for her to get close in time, but An An's direction could not be adjusted because of airflow control! Please don't doubt this, because sometimes the updraft is so strong that even experienced pilots can't control it under the airflow control.

But at present, there are several options before Ann: resist the airflow, try to return to the descent trajectory, parachute immediately after landing and wait for rescue, change direction and land from another position. The last one is almost impossible, because the route is unfamiliar and the wings fly and glide, which is very poor. The route must be measured before flying, so the first two may be the last one, but it is obvious. Different from skydiving, An An seems to be very confident in her skills, and her indomitable character may choose the former.

But it is obvious that the airflow may be beyond her control, or the estimated value is slightly insufficient. After entering the mountainous area, the conditions for skydiving gradually lost. We know that parachutes must have a safe opening height. If it is lower than this height, even skydiving will die or be seriously injured because it is too late to open the parachute. So in the end, he is likely to cross the low-lying area for time and height to reach the slope on the other side of Tianmen Mountain. Unfortunately, this task cannot be completed, and it is euphemistically called unwilling to fail. Of course, this is only a simple analysis based on the terrain of Tianmen Mountain and the aerodynamic performance of wing movement.