Chapter 82 Engine Failure
Chang Haonan did not really need to wait for two days.
Because at the same time as the work coordination meeting was held in Shengjing, something happened to Yan Liang.
The time goes back half an hour.
Test pilot Lin Tingguang is flying the No. 01 prototype of the J-8-3 for the planned high-altitude and high-speed test flight project.
Although the subsequent two full-state prototypes No. 04 and 05 will be equipped with new wings, this does not mean that the test flight data of the two non-full-state prototypes No. 01 and 03 are meaningless.
In fact, unless the overall design is completely overturned like the Su-27 prototype T10, even if there are changes in the aircraft design, only some related subjects need to be supplemented with a new prototype.
Even if the change seems obvious.
For example, the No. 01 and No. 03 prototypes of the FC1 Xiaolong fighter jet still use the boundary layer partition inlet. Only from No. 04 did they start to use the DSI inlet.
Another example is that the six reinforcement ribs above the air inlet of the J-10 No. 01 and No. 03 prototypes really only play the role of structural reinforcement, but the arrangement was adjusted in the mass-produced model, and additional Spoiler effect.
What Lin Tingguang wants to test today has nothing to do with the wings, but to find the ultimate flight envelope under the current matching engine design——
Like all other equipment, the worse the engine's working condition, the worse the engine's working condition. The more likely it is to malfunction.
When the working conditions reach a certain critical value, the failure rate becomes unacceptable.
The level of this critical value determines the performance of the engine.
But like all other equipment, there is often a difference between the paper performance of an engine determined during design and its actual performance after it is manufactured and installed on the aircraft.
For some engines with relatively good stability, such as F110 or F404, the difference between the two will not be too big for the time being.
But for some engines with poor stability, such as the TF30 or the early F100, the paper performance has almost no reference value.
And the performance of the same engine installed on different aircraft is sometimes very different.
TF30 performed well when installed on the F111, but it was a complete disaster when installed on the F14.
So it is necessary for the flight test team to accurately determine where the actual limits of the engine are.
On the one hand, it allows pilots in combat units to know how to ensure that the aircraft is in normal working condition and reduce the accident rate.
On the other hand, it also produces enough data and gives it to the engine design and production units so that they can make more targeted improvements.
As for the turbojet 14, at least the turbojet 14 in its current technical state, it is undoubtedly the latter engine with poor stability.
So the test flight work requires even more care.
……
In the cockpit of the No. 01 prototype, Lin Tingguang pushed the throttle lever with his left hand gently, watching with his eyes as the flight speed on the HUD slowly exceeded Mach 1.8.
This is the speed he needs to maintain for the rest of the test flight.
“Prepare to conduct a yaw maneuver test flight.”
The tower commander’s voice came from the earphones.
"Received, yaw maneuver test flight."
After Lin Tingguang repeated the command, he began to use his hands and feet together, carefully coordinating the control of the stick and rudder, so that the aircraft gradually began to enter a side slip state.
"Starting to enter a sideslip." Lin Tingguang took a deep breath and reported to the tower.
Every second that follows feels like a century. The flight conditions with sideslip angle have exceeded the adjustment range of the adjustable inclined plate inlet, so the intake air flow distortion is very serious, which especially tests the stability and reliability of the engine.
Strictly speaking, this is a posture that should be avoided during normal flight.
But just like subjects such as stalling and spin, "abnormal" flight is already normal for the special group of test pilots.
Under the control of Lin Tingguang, the No. 01 verification aircraft successfully maintained a sideslip flight attitude for more than ten seconds, and then smoothly leveled off. During this period, everything was normal.
"Very good, the subject is completed, prepare to return. Please note that there is a strong crosswind in your current flying airspace."
The voice of the tower commander also became obviously much more relaxed.
The most dangerous part of this test flight has been completed.
"Received, ready to return."
Lin Tingguang in the cabin also breathed a sigh of relief, and at the same time began to slowly close the throttle, controlling the speed of the aircraft to slowly decrease to Mach 1.1.
However, just when everyone thought they were done, he suddenly heard a "bang" sound coming from the right air intake, and then the right engine speed dropped sharply, and there was a sense of shaking in the cockpit. It became violent.
"The right engine failed and lost thrust."
Although he faced aircraft failure at high speed, long-term training still allowed Lin Tingguang to calmly report the current problem, and Start thinking about troubleshooting.
He slowly closed the throttle almost subconsciously, then adjusted the aircraft's attitude to turn left and descend, aiming in the direction of the airport runway.
If it was just an ordinary engine stop in the air, then it still has enough speed. As long as the airflow drives the engine speed again, it should not be difficult to recover.
However, soon, a warning about the abnormal temperature of the right engine stopped him from restarting the engine in the air.
There is definitely a big problem.
There is no hope of restarting an engine that has been damaged.
Lin Tingguang looked at the altimeter that kept falling, his brain running rapidly, thinking about the current situation.
In the headset, the tower has even given instructions to allow parachuting. Although the J-8-3 aircraft has two engines, if a fire occurs in one engine, it is likely to affect the other one. The engine even disintegrated in the air.
The pilot will not be held responsible for parachuting at this time.
But as a test pilot, Lin Tingguang was unwilling to give up.
In addition to saving the aircraft itself, the fault data generated by this test flight is also very valuable. If it can be brought back intact, it will be of great help to the next improvement work.
So he hesitated for a few seconds.
It was in these few seconds that Lin Tingguang discovered that as he gradually closed the throttle and stopped supplying fuel to the engine, the temperature of the right engine was being controlled.
And he still has a certain altitude. If handled properly, it is entirely possible to return to the airport and land.
"Prepare to return to the airport to land on No. 01."
This sentence implies the risk of sacrifice at any time, but Lin Tingguang's tone seemed as if he was just describing what he had for breakfast.
The commander in the tower narrowed his eyes slightly and opened his mouth several times, but in the end he did not speak to affect the pilot's judgment. He just asked the emergency response team to prepare to set up a blocking net and prepare fire trucks and ambulances to deal with possible emergencies. Affection.
"The aircraft's hydraulic system failed, but the landing gear has been lowered."
A piece of good news, losing hydraulic pressure means that it will become extremely difficult to control each rudder surface. But lowering the landing gear at least means that as long as the plane touches the ground, safety is basically guaranteed.
(End of this chapter)