Characteristics of Apache helicopter gunships

AH-64 is the ultimate performance of attack helicopters at present. Its powerful firepower and heavy armor make it fly over the battlefield like a heavy tank. No matter day or night, no matter how bad the weather is, it can find and destroy the enemy at will and is almost completely fearless of any weapon of the enemy.

Detailed introduction

Performance: Just as the Tank Vehicle Command stipulates that all new vehicle designs must be fully maneuverable, the Army Aviation Center in St. Louis, Missouri also stipulates that all new helicopter designs must meet certain standards, such as maneuverability, protection against enemy fire, load capacity, etc. For example, AH-64 is not afraid of 7.62 mm bullets, but also can resist 12.7 mm (.50 caliber) bullets. At the same time, even if it is hit by a millimeter-class high-explosive bomb, it can still support flying back to the base.

The fuselage is designed to withstand the crash impact of 20G (20 times gravity) without injuring the crew, and the fuel tank is also designed to withstand the crash impact and automatically close.

The new helicopter of the U.S. military has a device to suppress infrared signals from the beginning of its design. Infrared missiles are the main threat to low-altitude aircraft. The mark on the warhead of the infrared missile launched by the enemy is mainly to find the hot exhaust pipe of the gas turbine engine. One way to reduce the effectiveness of this missile marker is to mix the hot air discharged from the helicopter engine with a lot of cold air, exclude them from the fuselage, and isolate the exhaust pipe, so that the missile will not "see" the hot metal. AH-64A Apache's "black hole" infrared suppressor has a strong function in this respect.

equipment

Helicopters also need ECM to survive in modern battlefields. Electronic counter is a highly confidential and developing technology, and its instruments and performance are usually confidential, but a typical "black box" may include the following instruments and equipment:

(1) Radar warning receiver-used to warn the crew on board and let them know that they have been followed by enemy radar, so as to take evasive action.

(2) Radar jammer-it will send out jamming signals to obstruct and interfere with the enemy's radar.

(3) Jamming wire spreader-it will emit a cloud covered with metal, which can strongly absorb a specific radar frequency, interfere with the enemy radar screen and hide the real target.

(4) Thermal flame bomb launcher-can be used to "mislead" infrared missiles.

(5) Infrared jammer-Generally speaking, this is an electronically heated "brick" installed at the tail of a helicopter, which can emit very strong infrared rays with a specific wavelength, confusing sensitive marks on enemy missile warheads and causing trouble. The existing infrared jammer model number is ALQ- 144, and it is also nicknamed "disco ball" because of its unique shape.

All these advanced equipment make American helicopters the best in the world. This is not to say that it is unstoppable, but it is quite solid compared with American helicopters during the Vietnam War. As for the load, the combat experience in the jungle of Southeast Asia has exceeded the ability to fight in hot climate, which has become one of the necessary conditions for all new helicopter designs. The magic number "4000/95" is used to measure helicopter performance. The figure shows the helicopter performance with 95% throttle vertical climb at 95 degrees Fahrenheit (35 degrees Celsius) under standard load. This situation is close to the worst engine conditions (gas turbines can produce maximum horsepower in cold air and minimum horsepower in hot and humid climate) and may be encountered in the Persian Gulf and Panama. This standard is very reasonable if the geographical location of the world's unrest sites is taken into account.

Walking around Apache will give you a feeling that no one actually designed this kind of plane, but a group of people wearing eye masks combined some parts with paste and tape. Its rotating wings droop, the fuselage angle is almost unreasonable, and many parts protrude from one side or the other. Don't misunderstand Apache because of this. You know, Apache is the best and most complete weapon system in the world.

Its body shell is mostly aluminum alloy, and the hood is designed to support the weight of maintenance personnel and serve as a working platform. In addition, the whole machine is designed as a folding package, which is convenient for transportation of various air force transport planes.

The two engines on board are GE T-700-GE-70 1C, each with 1800 horsepower. They are connected with the traditional main transmission system, and the tail rotor is driven by the transmission shaft running through the tail. Like all traditional single-rotor helicopters, this tail rotor is used to balance the rotating torque of the main rotor to maintain the correct flight attitude. The main rotor in front of the plane is installed above the transmission system and has four large blades, so it is better than the previous two-blade rotors of UH-l and AH- 1. More blades can increase the lift of helicopters, and they can fly more smoothly and quietly. However, there must be enough engine power to maintain their high-speed flight, and good engineering technology should be used to design a rotor head that can maintain their balance and control and be firmly connected with the fuselage. Some Soviet helicopter designs even have five or six blades.

In fact, after hearing the familiar helicopter sound, most people find that the helicopter rotor has changed from two sections to four sections, and from "whirring" to a low roar.

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Most avionics and other "black boxes" are installed in the drag reduction devices on both sides of the front fuselage, which become the stairs for people to climb into the Apache cockpit. The cockpit itself is divided into the front (for the co-pilot and gunner) and the rear (for the driver) by a thick transparent bulletproof plate. The cockpit glass is all plane design, and this special shape is mainly to reduce the reflection of solar light, because the reflection of solar light will expose the position of the helicopter and let the enemy find it. The armored structure of the cockpit can withstand the direct hit of 23mm high-explosive bomb. The front and rear of AH-64 cockpit are equipped with standard flight control devices and display screens needed to control helicopter flight. In addition, each crew member on the ship also has his own specific task instruments.

The most important ones are Martin marietta (now merged with Lockheed) "Target Acquisition Calibration Sight" and "Pilot Night Vision Sensing System" (TADS/PNVS), which are installed on Apache's nose. The "night vision sensing system for pilots" is located above the Apache turret and includes a thermal imaging sight (similar to that used in abrams and Bradley cars), which moves synchronously with the pilot's flying helmet. This helmet is an outstanding design, which can be adjusted according to the head shape of each crew member, so that he or she can aim with helicopter weapons and sensors as long as he or she turns his head.

This system can be used at any time, no matter Apache is in bad weather. It can be used in dense fog, dust or at night. What the pilot sees will be displayed on a small circular display screen on the helmet, which is located in front of the right eye. This front display will also display other navigation and shooting control information, so that pilots can get all kinds of information needed on the battlefield at any time.

Other instruments on the control panel have also been specially designed, so the night vision ability of the pilot will not be affected even if the lights are turned off. Most of them are so-called "thin strip" displays, which display all kinds of information in a straight line, but there are also some round instruments that can be seen on the dashboard of cars. When Apache was originally designed, the configuration in the cockpit was considered to be the most advanced. The next generation Apache (like AH-64D "Longbow" Apache model) will replace most of the current instruments with electronic display screens controlled by large multifunctional computers.

Apache's main navigation system is Lipton's Attitude-Flight Direction Reference System (AHRS), which is the standard equipment for most army helicopters. This heading reference system can cooperate with ASN- 137 Doppler velocimetry system (this is a down-looking radar, which can feel various movements relative to the ground). Within a few hours, AHRS can be "transferred" from one fixed location to another. Therefore, most Apache have a GPS receiver in front of their cockpit, so that gunners can type the correct information by hand. Soon, a slightly modified AHRS system will be installed, and then AHRS can automatically receive the latest information of GPS.

In the front cockpit, it is the main control system of Apache weapon system. Although weapons can be fired in the front and rear cockpit, the shooter in the auxiliary cockpit is mainly responsible for Apache's weapon aiming at the target, and the weapon system on Apache aims at the TADS/PNVS system installed under the nose induction turret. The system includes another set of "forward infrared" sensors, a daytime TV camera, a set of direct-view amplification optical system, a laser rangefinder and a laser target calibrator for laser-guided weapons. The flying helmet worn by the gunner is also equipped with a sight similar to the back seat, and there is also a front display screen that can display the target and related information. When the shooter wants to deal with a target, he just needs to choose the right weapon, aim the "dead point" on the helmet sight at the target, and then pull the trigger. Most of the next work is completed by the on-board launch control system.

The main purpose of any weapon is to destroy the enemy, and AH-64 can destroy almost any target it detects. Under Apache's bow is a 30mm M230 chain gun (made by McDonnell Douglas), which fires a light 30mm shell instead of the 25mm green gun used in the A- 10 GAU-8 fighter gun. This shell, numbered M789, has a small cone-shaped charge warhead, which can penetrate armor several centimeters thick. This means that it can destroy a tank from above or from above, and it can destroy almost any armored personnel carrier or combat vehicle currently in use (except perhaps Bradley combat vehicle and British "Warrior" combat vehicle). M789 shells also have fragments, which are most effective for enemy ground forces exposed to gunfire. The loader of this M230 chain gun can load 1200 shells.

The rest of Apache's weapons are hung on short wings on both sides of the fuselage, and there are pylons under each wing, where missiles and rocket launchers can be installed. At present, there are plans to install a pylon above the wing and install two small air-to-air missiles. Some Apache helicopters of the US Army use stinger missiles for air-to-air operations. Although there is no chance to use needle missiles and M230 chain guns in the "desert storm", it can be seen from the air combat experiments using these two weapons that Apache's weapons and equipment are sufficient to deal with any aircraft flying into its range. This does not mean that Apache crew can shoot down high-performance jet fighters, but can shoot down other helicopters and ground support aircraft, such as Russia's Su -25 frog-foot attack aircraft.

Small unguided rockets have been one of the weapons of helicopters since they were equipped with weapons, and AH-64 is no exception. It is equipped with a powerful 2.75-inch (70 mm) rocket (made by North Defense Systems). This rocket, nicknamed "Hydra -70", can carry all kinds of warheads, from 10 lb (4.5 kg) high-explosive (M 15 1) warheads to smoke bombs (M264) and flares (M255) and sub-caliber ammunition warheads (M266). Each rocket includes an MK66 rocket propulsion, a warhead and an appropriate fuse (triggered detonation, delayed detonation or air detonation). "Hydra -70 usually carries a launch pod, which can launch 19 rockets. AH-64 can carry four such pods, but during the" desert storm ",it usually only carries two. When the attack goes deep into enemy territory, Apache usually adds an auxiliary fuel tank to extend the flight range, thus reducing one or more rocket launch pods.

Apache helicopter has deeply understood the necessity of long-range anti-armor missiles from the beginning of its design. TOW missile's anti-armor effect is quite good, but due to the limitation of guidance cable, its range is only about 3.7 kilometers. Moreover, after the tow missile is launched, the launched helicopter must remain stationary until the missile hits the target. Therefore, in the detailed specifications of the "attack helicopter" plan, it is stipulated that its weapon system must include brand-new anti-armor missiles. Rockwell International Company and Martin marietta Company are responsible for the development and production of this brand-new missile, which is the Hellfire missile numbered AGM- 1 14.

Hellfire is a missile slightly larger than a towed missile, weighing about 99.6 pounds (45.3 kilograms). Unlike towed missiles, Hellfire missiles are guided by the laser target calibrator of the TADS/PNVS system on the Apache helicopter nose, so they have a longer range (more than 5 miles /8 kilometers) and a faster speed (supersonic speed). Its front and rear warheads (with two conical charges, one in the front and one in the back) are also much larger than TOW-2, which has a charge of more than 20 pounds (9. 1 kg). If you don't know the extent of the damage caused by this amount of explosives, then I can tell you that the early AGM- 1 14C warhead only had a cone-shaped charge, but it could not only blow through the armor of Iraqi T-72, but even blow it in half from the weld!

Hellfire missile can find the target because the optical marker at the front end of its warhead has been set up, and it can find the target calibrated by Apache TADS/PNVS system with laser spot, or the target calibrated by other models such as OH-58D laser target calibrator. Even the laser target calibration pod under the belly of the Air Force F- 15E can designate targets for Hellfire missiles.

A fighter-bomber can only throw a laser-guided bomb at a single target at a time, while Apache helicopters can simultaneously launch multiple Hellfire missiles on the same battlefield and attack multiple different targets. Every Hellfire missile must "know" which laser spot to attack. So Hellfire missiles (and other laser-guided weapons at present) will only attack a laser spot with a specific digital signal, which is set by the plane that emits the laser spot. This not only solves the problem of keeping multiple missiles shooting at targets in different positions, but also enables a helicopter or a ground observer to specify the targets to attack and then instruct other helicopters to launch Hellfire missiles at these targets.

Therefore, the helicopter launching the missile can hide behind the hill to avoid being attacked by the enemy's gunfire (the autopilot of Hellfire missile can be set to let the missile fly over the hill to the target), while another helicopter equipped with laser target calibrator can "calibrate" the target to be attacked from a completely different direction. The OH-58D is equipped with a sight mounted on the mast, which can extend the head of the sight out of the treetop or ridge line, and then guide the Hellfire missile to the target without exposing the position of any other helicopter. Another interesting feature of Apache is that it can fire missiles continuously at short intervals (for example, 5 seconds). If Apache's shooter wants to attack three or four tanks in a row, he can launch the first laser-guided missile to attack the first tank, then quickly attack another tank and then attack the next tank until all the tanks are destroyed or all the missiles on the plane are shot out. In case Apache has no needle missiles available, Hellfire missiles can even be used as air-to-air missiles. If a plane as big as a helicopter is hit by a Hellfire missile, it will definitely die!

During the development of Hellfire missile, everything was carried out as planned and did not exceed the budget. There are no major technical problems, just some modifications. Adding a dual-mode warhead (used to deal with explosive reaction armor) and a new type of digital automatic guidance instrument to the basic A Apache helicopter (so that gunners can choose to let the missile fly to the target with high or low bombs), so that the existing AH-64A Apache has AGM- 1 14F anti-tank missiles, just like the OH-58D "Chiowa Warrior". On the other hand, it is planned to develop a new type of millimeter-wave guided missile, called "Longbow Hellfire" missile, which will be launched and used in a few years.