The George Yates of Beaverton, Oregon, Oregon O was developed into the 1935 twin-engined Greenwood-Yates Bi-Craft (NC15546) with 50 hp engines.
Yates and partner Allan D. Greenwood (a pilot and Oregon state aircraft inspector) formed the North Pacific Aircraft Corp. to market the Bi-Craft geodetic-construction light twin design.
Through a joint programme with Yakolev of Russia, Aermacchi is assisting in developing the Yak/AEM-130 to meet the Russian Air Force’s requirement to replace the L-29 and L-39. The aircraft is equipped with a quadruplex fly-by-wire flight control system and will be required to fulfil a broad range of tasks: from basic flying training to weapons training and aircraft carrier deck training. The aircraft are equipped with wingtip- and pylon mounted AAMs with a roulette and sensor pod also fitted.
The joint Italian/Russian Yak 130 technology development programme ran from April 1996 to December 1999, accumulating some 300hr flying. The two seat Yak-130 fighter/trainer was exported as the AEM-130.
The Yak-130 became all Italian in 1998 and served as a basis for the Aermacchi M-346.
Engine: 2 x Klimov RD-35, 22kN
Max take-off weight: 5400-6200 kg / 11905 – 13669 lb
Wingspan: 10.6 m / 35 ft 9 in
Length: 11.3 m / 37 ft 1 in
Height: 4.8 m / 16 ft 9 in
Wing area: 17.6 sq.m / 189.44 sq ft
Max. speed: 1000 km/h / 621 mph
Ceiling: 12500 m / 41000 ft
Range: 1850 km / 1150 miles
Crew: 2
In 1962 the Yakolev bureau was chosen to produce the first Soviet vertical take-off and landing aeroplane for the Soviet navy’s new ‘Kiev’ class of aircraft-carriers. Initial consideration was given to a composite arrangement of lift jets and a cruise engine, but it was finally decided to use two 36.78kN Koliesov engines with vectoring nozzles on the centre of gravity to provide direct lift or forward thrust as required. The airframe designed for the new Yak-36 was necessarily broad to accommodate the side-by-side engines, used the now-standard arrangement of tandem main units on the centreline together with stabilizing outriggers at the wingtips, and was completely conventional as only high subsonic speeds were envisaged. Hovering control was provided by reaction jets in the wingtip pods, the tail and the long nose boom. The type first flew in the mid-1960s, and trials with at least 12 such prototypes paved the way for the Yak-38 VTOL naval aeroplane, which has a composite powerplant with one vectored thrust turbojet in the rear fuselage, and two lift turbojets in the forward fuselage.
Displayed publicly at the Domodedovo, Moscow, flying display in July 1967, this single seater appeared to be powered by two turbojets installed side by side in the belly, each discharging through a louvred and gridded swivelling nozzle. The nose was occupied by large lateral air ducts from a bifurcated pitot inlet. Freehand had no lift jets, and pipes from the main engine served reaction control nozzles at the tips of the wing, at the tail and on the end of an outsize nose boom. The wing was mounted in the mid position directly above the engine nozzles. The vertical tail was sharply swept, and two ventral fins were fitted under the rear fuselage. A large surface under the nose, double hinged to function as an airbrake, was also hinged at the rear, and was judged to reduce reingestion of hot gas in the low level hovering mode.
Two Freehands took part at Domodedovo, one No 37 and the other No 38, the latter carrying two UV 16 57 rocket pods. Fitting the latter was considered chiefly a public relations exercise. There is no evidence to suggest that it was ever an operational type, though at least eight were built, and one went aboard the helicopter ASW cruiser Moskva where it conducted flying trials from an elevated platform not quite the same as those often used by Ka 25 helicopters.
Engines: 2 x RD-27-300, 53.0kN
Max take-off weight: 8900 kg / 19621 lb
Wingspan: 10.5 m / 34 ft 5 in
Length: 17.0 m / 56 ft 9 in
Height: 4.5 m / 15 ft 9 in
Max. speed: 1010 km/h / 628 mph
Ceiling: 12000 m / 39350 ft
Hardpoints: 2
Crew: 1
A light bomber and reconnaissance aircraft (NATO code name ‘Brewer’), and all weather fighter (NATO code name ‘Firebar’) and trainer (NATO code name ‘Maestro’). The Yakolev Yak-28P Firebar was a two-seater transonic all-weather twin-jet interceptor with a maximum speed of Mach 1.1 at 35,000 feet and a service ceiling of 55,000 feet. The Yak-28 first flew on 5 March 1958.
Possessing no more than a configurational similarity to preceding twin-engined Yakolev combat aircraft, the Yak-129 multi-role aircraft was first flown on 5 March 1958 in tactical attack bomber form. Powered by two Tumansky R-11AF-300 turbojets each rated at 5750kg with afterburning and 3880kg maximum military power, the Yak-129 had a shoulder-mounted wing swept back 63 degrees inboard of the engine nacelles and 44 degrees outboard. Although of zero-track arrangement as on the Yak-25 and -27, the undercarriage of the Yak-129 consisted of long-base twin-wheel units sharing aircraft weight almost equally.
Assigned the service designation Yak-28 and first shown publicly during the 1961 Aviation Day Display in Moscow, the first series version of the aircraft was the Yak-28B with an RBR-3 radar bombing system. This was followed by the Yak-28I and -28L tactical attack aircraft, differing in avionic equipment, which were joined under test during 1960 by the Yak-28P dedicated all-weather interceptor fighter. This featured tandem cockpits for the two crew members and was intended for low- and medium-altitude operation with an Orel-D radar and one beam-riding and one radar-homing R-30 (K-8M) AAM. The Yak-28P entered IA-PVO service during the winter of 1961-62.
The Yak 28 series, comprising the Brewer bomber in addition to the Firebar intercepter, was substantially larger and more powerful than its predecessor. Area ruling was adopted for the fuselage and the wing, of increased area, carried 50 degrees of sweepback on the inboard leading edge. Firebar is powered by a pair of Tumansky R 11 turbojets, the power of which has progressively been uprated since the aircraft entered service. Late production versions are powered by variants rated at an estimated 4600 kg (10140 lb) of dry thrust each, or 6200 kg (13670 lb) with afterburning.
The major differences from the Brewer, which was developed in parallel, lay in the forward fuselage. A radome replaced Brewer’s glazed nose, and the windscreen of the two crew cockpit was, along with the forward undercarriage leg, mounted some 76.2 cm (2.5 ft) further forward in the intercepter version. The internal weapons bay fitted to Brewer was deleted from the intercepter, and Firebar’s lengthened fuselage was later also adopted for the strike variant. A longer and more pointed radome was fitted to later production Firebars.
Firebar is fitted with an X band Skip Spin search and fire control radar operated by the rear crew member.
Standard armament comprises four AA 3 Anab air to air missiles, two of which use infrared guidance while the other pair employ semi active radar homing. A Yak 28P has been displayed with one Anab and one AA 2 Atoll under each wing, but this is thought to have been only an experimental installation. Firebar had by 1978 been mainly replaced by the Flagon E variant of the Sukhoi Su 15.
Progressive upgrading resulted in R-11AF-2-300 engines uprated to 3950kg and 6120kg with afterburning, and enclosed by forward-lengthened nacelles, a longer, sharply-pointed radome housing an upgraded radar and affording lower supersonic drag and reduced erosion, and an additional stores station beneath each wing permitting two short-range dogfight IR missiles to be carried. With all these changes incorporated the designation was changed to Yak-28PM. With further upgrading, the fighter was evaluated as the Yak-28PD, but this suffered high-speed aileron reversal during trials, and by the time that this problem had been overcome production of the Yak-28P was phasing out, terminating in 1967 with limited production of the Yak-28PP electronic warfare version. Production of the fighter totalled 437 aircraft.
Yak-28P
Span: 12.5 m (41 ft)
Length: 22 m (72 ft 2.25 in)
Gross weight: 18500 kg (40785 lb)
Maximum speed: Mach 1.15
(all figures estimated)
Yak-28PM
Max take-off weight: 15700 kg / 34613 lb
Wingspan: 11.64 m / 38 ft 2 in
Length: 20.65 m / 68 ft 9 in
Max. speed: 1890 km/h / 1174 mph
Ceiling: 16000 m / 52500 ft
Range: 2630 km / 1634 miles
In 1955, the Yakolev OKB flew the prototype of a light tactical bomber, the Yak-26, which, evolved from the Yak-25, embodied aerodynamic refinement and was powered by two Tumansky RD-9AK turbojets each rated at 3250kg with afterburning. During test, the Yak-26 achieved 1235km/h at 3000m, or Mach = 1.05, but suffered from serious instability at high attack angles, development consequently being discontinued in favour of a tandem two-seat all-weather fighter, the Yak-27, as a potential successor to the Yak-25. Similarly powered to the Yak-26 and flown in 1956, the Yak-27 featured extended wing root leading edges increasing sweepback inboard of the engine nacelles to 62 degrees, and a sharply pointed nose radome to reduce drag and lessen rain erosion. Armament remained paired 37mm N-37L cannon, but provision was made to supplement this with two RS-2U beam-riding AAMs. Parallel development was undertaken of a tactical reconnaissance aircraft, the Yak-27R, which accommodated the navigator in a pointed, glazed nose. Recurrence of the instability problems that had afflicted the Yak-26 led to major redesign of the wing, broader-chord outer panels being introduced and the tips were extended beyond the outriggers which were enclosed by streamlined under-wing blisters.
The Yak 27P was dubbed Flashlight C on its appearance at the Tushino Soviet Aviation Day in 1956.
Series production of the Yak-27 fighter was not undertaken – although 180 examples of the Yak-27R were built – but a single-seat mixed-power development, the Yak-27V, underwent extensive evaluation. Intended as a high-altitude interceptor and first flown in May 1957, the Yak-27V was powered by two RD-9Ye turbojets with an afterburning thrust of 3800kg each and a tail-mounted Dushkin S-155 bi-fuel rocket motor of 1300kg. Basic armament remained two 37mm cannon. The Yak-27V attained zoom altitudes of up to 25000m during a test programme that continued for two years, but the disbandment of the Dushkin OKB and a loss of interest in rocket propulsion resulted in termination of the programme.
Max take-off weight: 11340 kg / 25001 lb
Wingspan: 11.90 m / 39 ft 1 in
Length: 16.76 m / 55 ft 0 in
Height: 4.05 m / 13 ft 3 in
Max. speed: 1150 km/h / 715 mph
Ceiling: 15250 m / 50050 ft
Range: 3000 km / 1864 miles
In 1955, the Yakolev OKB flew the prototype of a light tactical bomber, the Yak-26, which, evolved from the Yak-25, embodied aerodynamic refinement and was powered by two Tumansky RD-9AK turbojets each rated at 3250kg with afterburning. During test, the Yak-26 achieved 1235km/h at 3000m, or Mach = 1.05, but suffered from serious instability at high attack angles, development consequently being discontinued in favour of a tandem two-seat all-weather fighter, the Yak-27
Engines: two Tumansky RD-9AK turbojets, 3250kg with afterburning
In the summer of 1951, the NKAP issued a requirement for an all-weather interceptor fighter possessing sufficient internal fuel capacity to mount standing patrols of up to 2.5 hours duration and capable of accommodating a large, new radar. This supplanted an earlier requirement to which the Mikoyan-Gurevich I-320 and Lavochkin La-200 had been evolved. The new radar, known as the Sokol (Falcon), had a 80cm diameter dish, three different scan modes and an installed mass weight of almost 500kg. To meet this new requirement, the Lavochkin and Yakolev OKBs respectively developed the La-200B and Yak-120. The latter, an all-metal stressed-skin tandem two-seater, was powered by a pair of small-diameter Mikulin AM-5A turbojets each rated at 2200kg / 4850-lb and hung beneath a wing swept back 45 degrees at quarter chord and carrying some 3 degrees of anhedral, and mounted in full-mid position. The undercarriage was of zero-track type, with wingtip-housed outrigger stabilisers, and armament comprised two 37mm N-37L cannon with their barrels accommodated in external fairings beneath the fuselage.
From 1957 the Mikulin AM 5 turbojets were replaced in the definitive Yak 25F by Tumansky RD 9s of 2600 kg (5730 lb) thrust, increasing the maximum speed.
The first of three Yak-120 prototypes was flown on 19 June 1952, State acceptance testing paralleling construction of a pre-series of 20 aircraft for avionics development and, commencing late 1953, service evaluation. With ballast equivalent in weight to the Sokol radar – which did not attain service status until late 1955 – the Yak-120 had a loaded weight of 9220kg, series production commencing late 1953 as the Yak-25 with RD-9 turbojets each rated at 2630kg. Confusing repetition of the “Yak-25” designation resulted from its initial use as an OKB appellation and subsequent use by the NKAP as an official and sequential designation, the previous Yakolev service fighter having been the Yak-23. The Yak-25 was assigned primarily to defence sectors in the Far North of the USSR, production being completed in 1958 after the delivery of 480 aircraft and service phase-out taking place in the mid ‘sixties.
The production programme took the type right through toward the end of the 1960s in role-differentiated models designated Yak-25, Yak-26 and Yak-27 with swept wings and on the Yak-25RD high-altitude reconnaisance version with straight wings.
The intercepter was codenamed Flashlight-A by NATO’s Air Standards Coordinating Committee, Flashlight B being a reconnaissance variant developed concurrently for service with the Soviet air force’s frontal aviation or tactical air arm.
A tactical reconnaissance derivative with the navigator accommodated in a glazed nose was built in 1953 as the Yak-125, but was not produced in series owing to prior adoption of the IL-28R. Other derivatives of the basic design were the Yak-25L ejection-seat test bed with individual cockpits, and the Yak-25RV long-range high-altitude strategic reconnaissance aircraft.
The Yak 25R carried the second crew member in a pointed glazed nose instead of behind the pilot, and armament was reduced from the intercepter’s pair of 37 mm (1.46 in) NR 37 cannon to a single 23 mm (0.90 in) weapon in the right-hand side of the forward fuselage.
Engines: 2 x Klimov VK-5, 8820 lb thrust
Max take-off weight: 10900 kg / 24031 lb
Wingspan: 11.00 m / 36 ft 1 in
Length: 15.67 m / 51 ft 5 in
Height: 4.32 m / 14 ft 2 in
Wing area: 28.94 sq.m / 311.51 sq ft
Max speed: 1090 km/h / 677 mph
Cruise speed: 820 km/h / 510 mph
Ceiling: 13900 m / 45600 ft
Range: 2730 km / 1696 miles
Armament: 2 x 37m cannon
Soviet rotorcraft development was suspended during World War 2, and it was not until late summer 1952 that the USSR made its first major effort to close the design gap between itself and the USA in regard to large transport helicopters. In response to order of Stalin at a Kremlin meeting autumn 1951, two basic projects were selected, the first, for a 12-passenger machine of single main rotor configuration, being assigned to the Mil design bureau. The second, entrusted to the bureau headed by Aleksandir S. Yakolev, was for a twin-engined, tandem-rotor machine capable of seating 24 passengers. Prototype flights of both types were required to take place within one year.
Mil had already prepared suitable design, and Yak gained permission to use essentially same main rotor and drive from similar engine, merely doubling up to use two engine rotor systems at ends of boxcar fuselage. Yak assembled a large team including Erlikh, veteran helicopter man N.Skrzhinskii, P.D.Samsonov (famed flying-boat designer who had long managed Yak prototype dept), L.Shekhter, L.S.Vil’dgrub and many other well-known engineers. The plan was to build four four Yak-24, already called LV (Letayushchii Vagon, flying wagon), two for static and resonance test and two for flight. Yakolev was promised “unlimited support” for the rush programme.
A S Yakolev has described how, in autumn 1951, he and other designers were called to the Kremlin and told by Stalin to create two helicopters, one to carry a useful load of 1,200kg or twelve armed infantry and the other just twice as much, prototypes to be ready in one year. It was to be a ‘crash programme’, with ‘unlimited support’ from the national research institutes. Nobody was eager, but eventually Mikhail L Mil agreed to tackle the smaller machine and Yakolev the larger, Yakolev having the idea of simply using tandem rotors based on those of the Mil’ design.
Designing the Yak-24 started in December 1951. Though the first prototype was built extremely quickly, this programme was to prove more protracted than any previous endeavour by the OKB. Including later versions the chief engineers comprised I A Erlikh (the original leader) and P P Brylin, Yu I Orlov, V P Lashkov, G I Rumyantsev and G I Ogarkov.
Mil, with CIAM, CAHI and other organizations, including Shvetsov’s engine KB, developed the rotor and its drive system. The engine was the ASh-82V, a special helicopter version of the fourteen-cylinder radial used in some Yak fighter prototypes. Rated at l,430hp, and with 1,700hp available for takeoff, it was developed with a cooling fan and centrifugal clutch and cleared to operate in any attitude. It was decided to install the front engine between the cockpit and cabin at an angle of 60deg to drive the gearbox under the front rotor. The rear engine was installed in the normal attitude in the base of an enormous rear fin which formed the pylon for the rear rotor, driving through a 90deg bevel gearbox.
The rotors had fully articulated hubs made of D16 and steel, with drag and flapping hinges and friction dampers. In fact, the rotor was not identical to that of the Mi-4, and indeed later Mil enlarged his rotor by using Yakolev’s longer blades. The four blades were tapered, with NACA-230 profile, based on a 30KhGSA spar with ply ribs and skin covered in varnished fabric, with tracking adjusted by a tab on the trailing edge near the tip. The fabric was replaced by a steel rotor with a metal skin on the production models. The rotors turned at 178 rpm in opposite directions, the rear rotor being a mirror image of the front rotor which it over-sailed. The gearboxes were linked by a torque shaft so that flight could just be maintained on one engine. Each engine was geared to drive one or both rotors. Unfortunately this arrangement, although intended as a precaution against failure of either engine, created the problem of ‘sympathetic’ vibration. From the outset, vibration hampered the Yak-24’s development.
The boxcar fuselage was based on a truss of welded KhGS A tube, originally fabric-covered, then skinned with unstressed Dl panels covering the engine bays, rotor pylons and fin, and by fabric elsewhere. Each engine was housed in a fire-resistant bay with large apartures for cooling air, those for the rear engine being forward-facing open inlets beside the fin leading edge. Each engine had its own fuel tank. At the front was the fully glazed cockpit for two pilots and a radio operator/engineer, with a sliding door on each side and a rear door to the engine compartment, through which a narrow passage led to the main cabin. Aluminium plank cargo floor with full-section access via rear ramp/door; passenger door forward on left side.
Rear rotor mounted on top of vertical fin (TE curved to right to give side-thrust to left in flight) with drive from engine installed in normal horizontal attitude at base of fin, with open cooling-air inlets each side of fin and clearance under engine for vehicles and other cargo on ramp. High-speed connecting shaft to front rotor, mirror-image with rotation anti-clockwise seen from above, driven by engine at 60° angle between cockpit and cabin. Nose cockpit for two pilots, radio-operator and engineer, entirely glazed with aft-sliding door each side and sliding door(s) at rear giving restricted access past engine to main compartment. This measured 10m long, the cross section being 2m square with intended accommodation for up to 40 troops on canvas wall seats or light vehicles or 4t cargo, with crane operation using central hook on underside of fuselage. There were six windows on each side, one being in a door, and at the back was a full-width ramp door through which shallow loads such as a GAZ-69 ‘Jeep’ could be moved under the rear engine on to the floor of aluminium planks. Four similar levered-suspension wheel landing gears, each normally castoring +/-30 deg, on rigid welded steel-tube outriggers. The track was 5m.
Two flying prototypes completed, and two others were built for static and dynamic testing. While numerous establishments tested complete engine/rotor rigs, blade fatigue and truss structure of fuselage, first flight article readied spring 1952 and began 300 hr endurance test with wheels tied down. Vibration in evidence from start, and usually severe. With greater experience OKB might have recognised a fundamental N1 main-rotor mode and altered critical dimension. As it was, at 178th hour, rear engine tore free from fatigued mounts, machine being destroyed by fire. Second flying article, ie, 4th airframe, finally began tethered flight piloted by Sergei Brovtsev and Yegor Milyutchyev 3 July 1952. Hops at partial power were followed by full-power flights, when vibration reared its head dangerously. Five months by every available expert found no cure; then Yakolev personally ordered 0.5m cut off each main-rotor blade, reducing diameter from 21m to 20m. This effected immediate great improvement. No.4 aircraft delivered for NII test Oct 1953, but destroyed when tethers snapped during ground running. OKB delivered improved aircraft with numerous mods including modified tail with no fins but braced tailplanes with dihedral 45°. This finally passed NII April 1955 and production began at GAZ in Leningrad.
With official tests completed on later prototypes, production began in April 1955, and only four months later evaluation aircraft were demonstrated at Tushino airport during the Soviet Aviation Day display. The first four pre-series Yak-24 (visibly not all identical) flew at Tushino, Aug 1955.
Final development work on the aircraft was extremely long and complex and full-scale production for the armed forces began in 1955, about 30 months behind schedule.
Series version had strengthened floor with tracks for vehicles, tie-down rings, attachments for pillars carrying 18
stretchers, full radio and night equipment and facilities for field servicing. Normal max load 20 armed troops or 3t.
The early Yak-24’s featured a Vee tailplane, but later production examples had rectangular endplate fins on a horizontal tailplane, and both have been seen with and without a narrow auxiliary rudder.
Production was ordered at a Leningrad factory, where thirty-five were built for the VVS in 1956-58. These were painted in dark green camouflage, and except for the first few had larger tailplanes with dihedral reduced to 20deg carrying large endplate fins set at an angle of 3deg 30′ to give the required thrust to the left in cruising flight, the tail end no longer being curved to the right. They had full equipment for loading and securing vehicles and other cargo up to a maximum of 3,000kg. Canvas wall seats were provided for twenty troops, with racks for weapons and equipment, with pillar sockets for eighteen stretchers accompanied by an attendant. A three-tonne load could also be slung from a central hook, but on 17 December 1955 Milyutichev carried an overload of four tonnes to 2,092m. On the same day G A Tinyakov set a second world record in the same prototype by taking 2,000kg to 5,032m.
At an air display in Moscow in July 1956 the Yak 24 made its first appearance.
Yak-24U (Uluchshennyi, improved) flew Dec 1957 with numerous mods resulting from prolonged research. Rotor blade length unchanged but diameter restored by adding long tubular tie at root. Side-thrust at tail reduced by canting axes of rotors 2°30′ (front to right,, rear to left), so curved rear of fin removed. Fuselage frame strengthened, metal skinned throughout and cabin increased in width 0.4m. Flight-control system fitted with two-axis autostab and autopilot of limited authority, developed within OKB. External slung load attached to winch in roof of cabin with large door in floor. Rear landing gear oleos changed in rate to eliminate last vestiges of ground resonance, and other minor changes including revised fuel system.
In production GAZ-33 early 1959, though halted at No 40. This variant could at last lift 40 troops or 3.5t and at least some production machines had tailplane dihedral 0°.
In January 1958 a complete three-axis autostabilization system was cleared for service and retrofitted to each helicopter. This dramatically improved stability and control, making hands off hovering possible. The USAF called this helicopter ‘Type 38’, later replaced by the ASCC name ‘Horse’.
Initial Yak-24 production was undertaken on behalf of the Aviatsya Vozdushno-Desantnich Voisk (Aviation of the Airborne Troops), in which configuration the aircraft could accommodate up to 40 fully-equipped troops according to range. Other typical loads of the “Letayuchiy Vagon” (Flying Wagon), as it was quickly dubbed, include 18 casualty litters, 2 anti-tank guns, 2 GAZ-69 command vehicles or 3 M-20 staff cars. In 1958 the Yak-24U became the standard military model, with all-metal rotor blades and fuselage skin, the revised tail configuration already mentioned, and the rotors restored to the original 21.00m diameter.
Yak-24U This Uluchskennyi (improved) helicopter was completed in December 1957, and tested from January 1958. The rotor blade spars were connected to the hub by oval-section steel tie rods at the root, restoring rotor diameter to the original design value. The axes of the rotors were canted 2deg 30′, the front hub tilted to the right and the rear to the left, so that the entire tail could be redesigned for minimum drag without the need to generate side thrust. Avionics included a two-axis autostabilization system and limited-authority autopilot developed mainly within the OKB. The fuselage truss was strengthened and increased in width by 0.4m and made slightly higher, and metal-skinned throughout. The external slung load rating was increased to 3,500kg, and the cable passed through a large floor hatch to a winch in the roof of the cabin. The rear landing oleos were modified to eliminate any tendency to resonance (now a better understood phenomenon), and later the fuel system was improved and the capacity significantly increased. This prototype could carry thirty-seven armed troops, but its main use was as a crane, putting roof trusses on the Pushkin (Ekaterinskii) palace and carrying gas pipes from Serpukhov to Leningrad over impassable marsh.
One example built by 1960 of Yak-24A (designation from Aeroliniya, airline) similar to late Yak-24U with horizontal tailplane and latest avionics but with comfortable civil interior for 30 passenger seated 2+1. Continious glazing down sides of fuselage, compartment for 300kg baggage and the rear freight door eliminated. Appeared in Aeroflot markings though never in service. The passenger door on the left was fitted with fold-down steps, and the cabin was fitted with larger windows.
Aeroflot (the Russian state airline) evaluated the Yak-24A commercial version, but turned it down. The Yak-24A can also be operated as a freighter or flying crane, being able to lift an external sling load of 5000kg. It also rejected the 1960 Yak-24K deluxe short fuselage version for 8-9 passengers. The fuselage was shortened, fitted with even bigger windows, improved soundproofing and heating and an electrically-operated airstairs, and luxuriously furnished for nine passengers. The Yak-24P for 39 passengers, with two 1500shp Isotov turbines mounted above the cabin was never built.
The Yak-24UB, flown in December 1957, included many design improvements and was placed in production from 1959, about 50 being delivered; this version could carry 40 fully equipped troops or up to 3500kg of cargo.
Yak-24
Engine: 2 x ASh-82V radial, 1268kW
Rotor diameter: 20.0m
Fuselage length: 21.34m
Max take-off weight: 16800kg
Empty weight: 11000kg
Max speed: 175km/h
Service ceiling: 4200m
Range: 266km
Crew: 3
Passengers: 30-40
A 1949 ten-passenger transport aircraft powered by two 559kW ASh-21 radial engines.
Engines: 2 x Ash-21, 515kW
Max take-off weight: 6400 kg / 14110 lb
Empty weight: 5200 kg / 11464 lb
Wingspan: 20.0 m / 66 ft 7 in
Length: 14.5 m / 48 ft 7 in
Max. speed: 370 km/h / 230 mph
Cruise speed: 300 km/h / 186 mph
Ceiling: 5000 m / 16400 ft
Range: 1000 km / 621 miles
Crew: 2
Passengers: 10
The Yak-6M was an improved version which finally led to the somewhat larger Yak-8, the prototype of which was first flown at the beginning of 1944. This was to have been a dedicated transport, essentially for military use, with accommodation for up to six passengers, but in the absence of anticipated higher-power engines its performance was disappointing and no series production ever took place.
All Aero 