Diagram of the cabin "An-24", its characteristics and photos

An-24 is a passenger turboprop aircraft. It is intended for short and medium range airlines. In its design there are 2 powerful turboprop engines (AI-24 series No. 2 or AI-24T) with an air-type propeller (AV-72, AV-72T). It has a flight range of 3,000 km, a cruising speed of 490 km / h, and a maximum take-off mass of 21 tons. This aircraft was produced from 1959 to 1979. More than 1,000 units of such aircraft were manufactured. To date, over 300 units are in use. Basically, the An-24 aircraft is used in the CIS and in African countries. This is a reliable fact. Next, we consider this model in more detail.

History

The development of the An-24 twin-engine turboprop aircraft, the operation of which was envisaged on local airlines, began in 1958 at GSOKB-473 named after O.K. Antonova. It was carried out on the basis of Decree of the Council of Ministers of the USSR No. 1417-656 of 12/18/1957. According to this document, the An-24 aircraft, the characteristics of which will be indicated later, should carry passengers with a load of 4000 kg over a distance of up to 400 km from a certain at a speed of 450 km / h. The use of AI-24 motors was also envisaged.

The An-24 aircraft made its initial flight on 10/20/1959. In this case, there was a crew at its helm, the command of which was carried out by test pilot G. Lysenko. Conducting subsequent factory and state tests fell on 1961.

Serial production of the An-24 began in the first half of 1962 at Kiev plant No. 473. In September of the same year, the first passenger flight was carried out. On October 31, 1962, the An-24 aircraft began to operate on the Kiev-Kherson route.

The production of this aircraft was carried out until 1979. From 1962 to 1979, more than 1,200 units were produced. Of these, 1028 were manufactured by the Kiev Aviation Plant Aviant. An analogue of this aircraft was also produced in China. Its name was "Y-7."

The design and layout of the aircraft "An-24"

This model is an all-metal freestanding monoplane with a highly located wing on it. There is also a three-post type chassis on which two front twin wheels are mounted. An-24 passenger aircraft consists of the following parts:

• The fuselage of the "semi-monocoque" type.
• Power set - stringers and beams. Connections are glue-welded.
• The layout is traditional: in front - a crew cabin, then between the luggage compartments - a passenger compartment with a buffet and a toilet.
• Wing: power set - two spars and 23 nerfures.
• Flaps: on the center wing - single-slotted. They are deviant. Next - double-slot retractable. The ailerons are split.
• Plumage is a traditional type with an extra ventral keel.
• Chassis: tricycle with swivel front strut.
• The wheels are double. Pressure regulation is carried out on the ground.
• Power plant: 2 TVD AI-24. In this case, the power is 2550 liters. from. There is a screw with a variable pitch. Its diameter is 3.9 m.

Design Advantages

The following benefits are available here:

1. The increase in the useful volume of the fuselage. This is due to the high center section.
2. A significant absence of wing tears in the upper part and manifestations that reduce the lifting force of the diffuser effect at the junction with the fuselage. This is an important property. As a result of this, the aerodynamic properties of the wing increase. By diffuser effect is meant the separation of the boundary layer of the flow due to the interference of the main one. It occurs at the junction of the wing and the fuselage.
3. Good lateral and longitudinal stability of the aircraft. It persists due to the absence of flow stall, as well as at supercritical angles of attack.
4. The presence of a high arrangement of engines. This allows you to operate the An-24 aircraft at unpaved airfields, since foreign objects are not sucked into the engine.
5. The high wing does not block the view of passengers and facilitates loading operations.

disadvantages

However, there are also disadvantages of this design. They are as follows:

1. Extra long landing gear requires large gondolas. This leads to an increase in resistance.
2. Compared to the low wing, this model creates a less efficient air cushion during take-off and landing .

The plane "An-24". Wing characteristics

In this case, it is:

• Area: 74.98 m².
• Profile:
  - 1-7 ribs (TsAGI-S5-18 is used);
  - 8-11 ribs - transition profiles;
  - 12-23 - TsAGI-SV-13.

In this model, the ribs are twisted with respect to the root at an angle from 2.5 ^about to 0 ^about . This, combined with a change in profile, provides aerodynamic and geometric twist of the wing, as a result of which flow lamination is ensured. This leads to a decrease in drag, an increase in the lifting force and effectiveness of the ailerons, as well as an increase in the speed causing the flutter effect.

• Elongation: 11.7. This is the ratio of the square of the magnitude to the area.
• Narrowing: 3.92. This is the ratio of the length of the chord of the root rib to the cantilever.

The narrowing and elongation in this case are selected so that, in combination with the twist, to ensure uniform load on the wing and reduce drag. A symmetrical flow failure at large angles of attack is also carried out.

• Sweep: no on the center section. Further to the console - 6.5 ^o .
• Cross V. Only at the console - -2 ^about .

This provides lateral stability. The result is increased controllability in the event of failure of one of the engines. This is also facilitated by an increase in vibrational stability and a decrease in roll towards the failed motor.

• Installation angle of a wing: 3 ^about . Selected to reduce fuselage drag due to its downstream position at cruising speed.
• Aileron asymmetric biconvex. Here the aerodynamic compensation is 29%.

Modifications of the specified model

In this case, it is:

• An-24V. Passenger aircraft with 50 seats. It is the basic primordial type. Perhaps its conversion into a passenger-and-freight and administrative.
• An-24RV. It is equipped with an accelerating turbojet engine with a capacity of 1950 liters. from. As a result of this, the main engines are quickly launched.
• An-24T is a purely transport version with a cargo hatch in the lower part of the fuselage. The plumage in this case has two under-tail keels on the sides of the hatch.
• An-24RT is also a transport view with an accelerating motor, like the An-24RV.
• "An-24LP" - modification for extinguishing forest fires.

Specifications

An-24 aircraft has the following technical specifications:

• Type: "An-24".
• Wingspan: 29.2 m.
• Fuselage length: 23.52 m.
• Airplane height parameter: 8.32 m.
• Wing Area: 72.46 m² Modifications with single-slot center wing flaps have 74.98 m².
• Weight: empty - 13.3 t; Curb - 13.75 tons
• Payload: 4.6 tons of cargo / 48 passengers / 38 soldiers / 24 stretchers.
• The maximum take-off weight is 21 tons. For the AN-24RV, it is 21.8 tons. On modernized aircraft, considering the strength of the landing gear, it is 23.5 tons.
• Fuel mass: 4.76 tons.
• Crew: 5 people.
• Power plant: 2 TVD AI-24A of 2550 liters. from. In the An-24RV modification, one engine for turbocharging is added.

Availability of flight performance

In this case, it is:

• Cruising speed: 490 km / h.
• Practical range: 990 km.
• Maximum speed: 540 km / h.
• Ferry range: 2820 km.
• Practical ceiling: 9100 m.
• Take-off run: 500 m.

Total

After reviewing the above, you can fully imagine what the An-24 looks like. In general, the model is not bad. In those days, the An-24, whose photo is in this text, was considered to be upscale in its own way.