Zhang Lan, who realized her mistakes, stayed at home very honestly this time, and corrected her mistakes very sincerely, and sure enough, she didn't go out for most of the month, but stayed at home and honestly accompanied her several real and nameless wives

A few little girls, including Yang Zhi and Zhang Zongjun, although a few girls don't know why this kid suddenly "twitched the wind again, and something is wrong with the tendon in his head", but this situation is undoubtedly their favorite to see...... What woman doesn't want to see the person she likes by her side all day long? And what parent doesn't want to see their children by their side?

Of course, even if he stayed honestly at home, Zhang Lan was not idle, during this time, he was accompanying Xiao Chenxi and Alice to do the work he earned from the Ministry of Defense before: developing a supersonic ramjet engine for small solid-fuel rockets powered by solid fuel for use in short-range air-to-air combat missiles and medium-range air-to-air missiles.

Something that is simple and absolutely complex.

Generally speaking, even short-range air-to-air combat missiles with a flight range of less than 20 kilometers generally weigh 70 to 100 kilograms, and the weight of the AIM-9 "Sidewinder" series of Americans, the world's representative work of short-range air-to-air combat missiles, is between 75 and 80 kilograms, which can be regarded as very light. Lao Maozi's R-73 series is another representative of the family of close-range air-to-air combat missiles, but it is a pity that Lao Maozi's electronic technology is not good, so the R-73 weighs a little more than 100 kilograms; As for our country's Thunderbolt-8 and Thunderbolt-9? It's more exaggerated, all over 120 kilograms.

As for medium-range air-to-air missiles with a flight range of between 60 and 80 km? The weight is more than 180 kg! To propelle a large guy weighing 120 kg to fly at a speed of at least Mach 3, and at the same time give this missile an overload capacity of at least 40 G, the requirements for the engine are naturally high, and it is natural to imagine.

However, since it is a weapon used for close combat combat and interception operations of fighters, the volume and weight requirements for the engine are naturally very strict: think about it, the missile diameter of the short-range air-to-air combat missile is only about 16 centimeters, and the diameter of the medium-range air-to-air missile is only a little more than 20 centimeters, but it is necessary to install many electronic components in this small volume, leaving how much space and weight for the engine?

The weight of each of the above parts is controlled in "grams"! What made Zhang Lan laugh and cry the most was that Zhang Lan took over the work of the engine used on the medium-range air-to-air missile

"Haven't I had enough to eat!" Ya smiled bitterly and sighed to Xiao Chenxi, who was simulating the final design.

"You also know that you are well fed?" The little girl glanced at this guy angrily, although in fact, the little girl was actually very satisfied with this guy's good performance during this time, but the little girl felt that in order to avoid this kid's previous "bad performance" in the future, it seemed that it was still necessary to watch this kid closer.

"Uh......" touched his nose a little ashamedly, in order to avoid being hit by this girl's "inhumane" criticism again, Zhang Lan decided to quickly change the topic to be safer, pointed to the data that was being quickly swiped on the three projections in front of him, and asked, "How is it?" ”

Xiao Chenxi is used to Zhang Lan's behavior of changing the topic at a critical moment, and this kid's performance is good for a while, and the sincerity of recognizing mistakes is very obvious, so he didn't care about Zhang Lan's behavior of "Gu Zuo is him" at the moment, and nodded and acquiesced to this kid's behavior of not answering his own questions, "Yes, it fully meets the requirements of the military, and the cost is lower than what the military requires, well, it is equivalent to 80 of what they require; The total weight is 15 percent lighter than the solid-fuel ramjet engines they used before, and I think your military should have nothing to dislike this time around. ”

"Good!" Zhang Lan swung her fist a few times excitedly!

He is very aware of the great significance of this engine to the domestic military in building a strong air force, and with the improvement of China's electronic and computer programming capabilities, the shackles on the construction of the air force in electronic technology and computer programming are no longer as great as before, so the main link that currently restricts the improvement of our air force's combat capability appears in the engine performance of missiles. Then this small rocket ramjet engine will increase the air combat capability and deterrence of the domestic military by at least two orders of magnitude!

Although many people now look at the strength of a country's air combat strength to see what type and generation of fighters they are equipped with, Zhang Lan understands that the strength of a country's air combat strength is not determined by the air performance of fighter jets, the performance of fighter itself only accounts for about 30, and the remaining 70 deterrent and combat effectiveness come from the air-to-air missiles carried by fighter jets.

After all, no matter how advanced the performance of the fighter itself, it is just an air combat platform, and the final battle still has to be solved by missiles. In air combat, missiles are the real weapons. A very simple example: Would you say that a Sanda champion with a machete is powerful, or a recruit who is 20 meters away from the Sanda Champion and holds a full automatic rifle in his hand?

"Bang~" Zhang Lan was unceremoniously slapped on the head! Xiao Chenxi looked at Zhang Lan who was habitually distracted there again with an unkind face, and the food indicator that was still there was still arched and waved at Zhang Lan authoritatively, and the little girl looked angry: Boy, don't go too far.

"Hehe~" Zhang Lan, who felt weak-hearted, hurriedly smiled flatteringly, "By the way, how long is the working time of the engine?" How much thrust is there? What is the specific impulse? ”

Engine operating time, thrust and specific impulse are the three most important statistics of modern air-to-air missile engines!

"Uh......" There is no way to take this cheeky guy, Xiao Chenxi glanced at Zhang Lan helplessly, and finally replied helplessly, "80 seconds, thrust 48.56kN, specific rush 300s." ”

"80 seconds? Thrust 48.56kN, specific impulse 300s? Very good. Zhang Lan nodded: At present, the world's most famous and at the same time the most advanced American-made AIM-9 "Sidewinder" series of short-range air-to-air combat missiles, the small solid rocket ramjet engine with less smoke and high impact ratio can only play for 60 seconds, and the thrust is only 26.68kN, with a specific impulse of 200 seconds. ,

Of course, Xiao Chenxi's design of the engine's performance is so strong, and it has a lot to do with the fact that the weight of the missile matched with this engine is too large.

Of the 87 kg of the AIM-9 air-to-air missile, the weight of the engine accounts for 35 kg, the weight of the engine fuel accounts for another 20 kg, and the remaining 32 kg is the weight of the missile's casing, explosives, prefabricated fragments, seeker, embedded computers, data link systems, and other electronic systems and explosive equipment.

However, this engine is used for the domestically produced Thunderbolt-9 series of short-range air-to-air combat missiles, and the weight of the Thunderbolt-9 short-range air-to-air combat missiles has reached 123 kilograms, which is 36 kilograms heavier than the AIM-9 "Sidewinder" short-range air-to-air combat missile, which is equivalent to 1.4 times the weight of the Sidewinder!

Then the thrust and specific impulse of this engine have to be stronger than the engine performance of the Sidewinder series of close-range air-to-air combat missiles, and the thrust of the engine with a thrust of 48.56kN is 1.82 times that of the Sidewinder missile engine, which is enough to offset the impact of the missile's too large weight.

The engine works for only 60 seconds? Or many people think that this data is too small, 60 seconds, isn't it only 1 minute! It's a ...... that an engine can only last a minute It's really ...... I guess none of these guys can find an adjective to describe it.

In fact, however, the maximum range of the AIM-9 "Sidewinder" close-range air-to-air combat missile, which flies at 2.5 times the speed of sound, is 17.7 kilometers, and the engine needs to work for only 21 seconds after flying this 17.7 kilometers! So for an air-to-air missile with a working time of only 21 seconds, an engine with a working time of 60 seconds is actually a bit wasteful.

Of course, some people have said that since the flight time of the missile is only 21 seconds, why should the working time of the missile engine be designed for such a long time, and it will not be designed to be 21 seconds? The question is...... Your missiles don't turn or slow down when they are flying! The opponent's fighter planes in the air in various maneuvers, sudden deceleration, flying close to the ground and other evasive actions, naturally do not allow the missile to fly at the highest speed, naturally to decelerate a little bit, in order to ensure the missile's flight performance and hit accuracy, if the plane you hit is like a fool to maintain a constant speed, direction, speed, altitude are unchanged, then it is not impossible.

Moreover, this is still the engine performance data of the AIM-9 "Sidewinder" short-range air-to-air combat missile of the early model, even if the latest AIM-9M "Sidewinder" short-range air-to-air combat missile equipped by the United States is equipped with the latest model of the MK36Mod11 rocket ramjet engine, the working time is still 60 seconds, but the performance has been improved, compared with the MK36Mod02 used on the AIM-9 "Sidewinder" short-range air-to-air combat missile of the earlier model -- MK36Mod0208 series single-stage thrust solid rocket engine, MK36Mod11 solid rocket ramjet engine performance has been improved a lot, the total impulse has increased by 30-40, and the specific impulse has also increased.

Of course, compared with the engine made by Xiao Chenxi, it is still worse in terms of performance.