Mil Mi-24 HIND

Development

During the early 1960s, it became apparent to Soviet designer Mikhail Leont’yevich Mil that the trend towards ever-increasing battlefield mobility would result in the creation of flying infantry fighting vehicles, which could be used to perform both fire support and infantry transport missions. The first expression of this concept was a mock-up unveiled in 1966 in the experimental shop of the Ministry of Aircraft’s factory number 329 where Mil was head designer. The mock-up designated V-24 was based on another project, the V-22 utility helicopter, which itself never flew. The V-24 was similar in layout and configuration to the UH-1A Huey, with a central infantry compartment that could hold eight troops sitting back to back, and a set of small wings positioned to the top rear of the passenger cabin, capable of holding up to six missiles or rockets, with a twin-barreled GSh-23L cannon fixed to the landing skid.

Mil proposed the design to the heads of the Soviet armed forces, and while he had the support of a number of strategists in the armed forces, he was opposed by several more senior members of the armed forces who believed that conventional weapons were a better use of resources. Despite the opposition, Mil managed to persuade the defence minister’s first deputy, Marshal Andrey A. Grechko, to convene an expert panel to look into the matter. While the panel’s opinions were mixed, supporters of the project eventually held sway, and a request for design proposals for a battlefield support helicopter was issued. The development of gunships and attack helicopters by the US Army during the Vietnam War convinced the Soviets of the advantages of armed helicopter ground support doctrine. This had a positive influence on moving forward with the development of the Mi-24.

Mil Mi-24 HIND A

Mil Mi-24 HIND A

Mil engineers prepared two basic designs: a 7-ton single-engine design and a 10.5-ton twin-engine design, both based on the 1,700 hp Izotov TV3-177A turboshaft. Later, three complete mock-ups were produced, along with five cockpit mock-ups to allow the pilot and weapon station operator positions to be fine-tuned.

The Kamov bureau suggested an army version of their Ka-25 Hormone ASW helicopter as a low-cost option. This was considered but later dropped in favor of the new Mil twin-engine design. A number of changes were made at the insistence of the military, including the replacement of the 23 mm cannon with a rapid-fire heavy machine gun mounted in a chin turret, and the use of the then-under development 9K114 Shturm (AT-6 Spiral) anti-tank missile.

A directive was issued on 6 May 1968 to proceed with development of the twin-engine design. Work proceeded under Mil until his death in 1970. Detailed design work began in August 1968 under the codename Yellow 24. A full scale mock-up of the design was reviewed and approved in February 1969. Flight tests with a prototype began on 15 September 1969 with a tethered hover, and four days later the first free flight was conducted. A second prototype was built, followed by a test batch of ten helicopters.

Acceptance testing for the design began in June 1970, continuing for 18 months. Changes made in the design addressed structural strength and fatigue problems, and reduced vibration levels. Also, a 12-degree anhedral was introduced to the wings to address the aircraft’s tendency to Dutch roll at speeds in excess of 200 km/h, and the Falanga missile pylons were moved from the fuselage to the wingtips. This gave the helicopter its characteristic wings. The tail rotor was moved from the right to the left side of the tail, and the rotation direction reversed. The tail rotor now rotated up on the side towards the front of the aircraft, into the downwash of the rotor, which increased the efficiency of the tail rotor. A number of other design changes were made until the production version Mi-24A (izdeliye 245) entered production in 1970, obtaining its IOC in 1971. It was officially accepted into the state arsenal in 1972.

Russia has developed the Mi-28 Havoc and Ka-50 attack helicopters, which are smaller and more maneuverable and do not have the large cabin for carrying troops. The Russian Navy however has no plans to retire their small number of Mi-24s. As for the Russian air force the service is severely short of funds, the “krokodil” will serve for many years to come.

Design

The core of the aircraft was derived from the Mil Mi-8 (NATO reporting name “Hip”): two top-mounted turboshaft engines driving a mid-mounted 17.3 m five-blade main rotor and a three-blade tail rotor. The engine configuration gave the aircraft its distinctive double air intake. Original versions have an angular greenhouse-style cockpit; Model D and later have a characteristic tandem cockpit with a “double bubble” canopy. Other airframe components came from the Mi-14 “Haze”. Two mid-mounted stub wings provide weapon hardpoints, each offering three stations, in addition to providing lift. The load-out mix is mission dependent; Mi-24s can be tasked with close air support, anti-tank operations, or aerial combat.

Mil Mi-8 Hip

Mil Mi-8 Hip

The body is heavily armored and can resist impacts from .50 caliber (12.7 mm) rounds from all angles, including the titanium rotor blades. The cockpit is an even more heavily armored titanium tub and can resist impact from 37mm cannon rounds. The cockpit and crew compartment are overpressurized to protect the crew in NBC conditions.

Considerable attention was given to making the Mi-24 fast. The airframe was streamlined, and fitted with retractable tricycle undercarriage landing gear to reduce drag. The wings provide considerable lift at high speed, up to a quarter of total lift. The main rotor was tilted 2.5° to the right from the fuselage to counteract dissymmetry of lift at high speed and provide a more stable firing platform. The landing gear was also tilted to the left so the rotor would still be level when the aircraft was on the ground, making the rest of the airframe tilt to the left. The tail was also asymmetrical to give a side force at speed, thus unloading the tail rotor.

A modified Mi-24B, named A-10, was used in several speed and time to climb world record attempts. The helicopter had been modified to reduce weight as much as possible, and among the measures used was to remove the stub wings.[5] The speed record over a closed 1000 km course set on August 13, 1975 of 332.65 km/h still stands, as does many of the female specific records set by the all female crew of Galina Rastorgoueva and Ludmila Polyanskaia. On 21 September 1978 the A-10 set the absolute speed record for helicopters with 368.4 km/h over a 15/25 km course. The record stood until 1986 when it was broken by the current record holder, a modified Westland Lynx.

As a combination gunship and troop transport, the Mi-24 has no direct NATO counterpart. Though some[who?] have compared the UH-1 (“Huey”) as NATO’s direct counterpart to the Mi-24, this is inaccurate. While UH-1s were used in Vietnam either to ferry troops, or were used as gunships, they were not able to do both at the same time. Converting a UH-1 into a gunship meant stripping the entire passenger area to accommodate extra fuel and ammunition, making it useless for troop transport. The Mi-24 was designed to do both, and this was greatly exploited by airborne units of the Soviet Army during the 1980–1989 Soviet war in Afghanistan. The closest Western equivalent was the Sikorsky S-67 Blackhawk, which used many of the same design principles and was also built as a high-speed, high-agility attack helicopter with limited troop transport capability; it, like the Mi-24, was also designed using many components from an already existing product, the Sikorsky S-61, itself a close approximation to the Mi-8/Mi-14. The S-67, however, was never adopted for service. Another relatively close western equivalent is the US MH-60L Direct Action Penetrator, a special purpose variant of the UH-60 Black Hawk which is capable of mounting a variety of weapons on its stub wings, including AGM-114 Hellfire missiles and Hydra 70 rockets, in addition to being able to carry up to 14 troops. The MH-60L is also similar in size compared to the Mi-24, but is more utility biased, lacks armor and can carry more troops and payload.

General characteristics

Crew: 2-3: pilot, weapons system officer and technician (optional)
Capacity: 8 troops or 4 stretchers
Length: 17.5 m (57 ft 4 in)
Rotor diameter: 17.3 m (56 ft 7 in)
Wingspan: 6.5 m (21 ft 3 in)
Height: 6.5 m (21 ft 3 in)
Disc area: 235 m² (2,530 ft²)
Empty weight: 8,500 kg (18,740 lb)
Max takeoff weight: 12,000 kg (26,500 lb)
Powerplant: 2× Isotov TV3-117 turbines, 1,600 kW (2,200 hp) each

Performance

Maximum speed: 335 km/h (208 mph)
Range: 450 km (280 miles)
Service ceiling: 4,500 m (14,750 ft)

Armament

Flexible 12.7 mm Yakushev-Borzov Yak-B Gatling gun

Flexible 12.7 mm Yakushev-Borzov Yak-B Gatling gun

Internal guns

  • flexible 12.7 mm Yakushev-Borzov Yak-B Gatling gun on most variants. Maximum of 1,470 rounds of ammunition.
  • fixed twin-barrel GSh-30K on the Mi-24P. 750 rounds of ammunition.
  • flexible twin-barrel GSh-23L on the Mi-24VP and Mi-24VM. 450 rounds of ammunition.
  • PKT passenger compartment window mounted machine guns

External stores

  • Total payload is 1,500 kg of external stores.
  • Inner hardpoints can carry at least 500 kg
  • Outer hardpoints can carry up to 250 kg
  • Wing-tip pylons can only carry the 9M17 Phalanga (in the Mi-24A-D) or the 9K114 Shturm complex (in the Mi-24V-F).

Bomb-load

  • Bombs within weight range (presumably ZAB, FAB, RBK, ODAB etc.), Up to 500 kg.
  • MBD multiple ejector racks (presumably MBD-4 with 4xFAB-100)
  • KGMU2V submunition/mine dispenser pods

First-generation armament (standard production Mi-24D)

  • GUV-8700 gunpod (with a 12.7 mm Yak-B + 2×7.62 mm GShG-7.62 mm combination or one 30 mm AGS-17)
  • UB-32 S-5 rocket launchers
  • S-24 240 mm rocket
  • 9M17 Phalanga (a pair on each wingtip pylon)

Second-generation armament (Mi-24V, Mi-24P and most upgraded Mi-24D)

  • UPK-23-250 gunpod carrying the GSh-23L
  • B-8V20 a lightweight long tubed helicopter version of the S-8 rocket launcher
  • 9K114 Shturm in pairs on the outer and wingtip pylons

And here is something for all of you Hind lovers… complete high resolution picture walkaround 😉

No matter if you are a 3D modeler or scale modeler, this is the reference you simply gotta have.
Of course, I included the blueprint 😉

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