Sukhoi Su-24 “Fencer”
Origin: Soviet Union.
Type: All-weather attack and reconnaissance.
Engines: Two afterburning engines (see below).
Dimensions: (estimated) Span (16°) 56·25ft (17·15m), (68°) 31·25ft (9·53m); length overall 69·83ft (21·29m); height 18·0ft (5·5m); wing area (16°) 50sq ft (46·4m2).
Weights: (estimated) Empty 39,700lb (18,000kg); loaded (clean) 64,000lb (29,000kg); max 87,080lb (39,500kg).
Performance: Max speed (clean, 36,000ft/11,000m) 1,590mph (2,560km/h, Mach 2·4), (clean, SL) about 870mph (1,400km/h, Mach 1·14); (max external load, hi) about 1,000mph (1,600km/h, Mach 1·5), (max external load, SL) about 620mph (1,000km/h); service ceiling (with maximum weapon load) 57,400ft (17,500m); combat radius (lo-lo-lo, 8t bombload) 1,115 miles (1,800km); ferry range (six tanks) about 4,000 miles (6,440km).
Armament: Eight identical MERs (multiple ejector racks) each rated at 2,205lb (1,000kg), four under fuselage, two under fixed gloves and two pivoted to swing wings, for total load of 17,635lb (8,000kg); glove pylons plumbed for largest drop tanks seen on Soviet aircraft; two large blisters cover items installed in the underside of the fuselage, one of which (and possibly both) is a gun.
Development: Spurred by the USAF TFX (F-111) programme, this aircraft was planned at the same time and using the same excellent aerodynamics as the MiG-23, but using two engines instead of one. Despite the fact that it is a fundamentally very old and uncompetitive engine, the consensus of Western opinions is that the Su-24 is powered by the AL-21F-3, or a close relative. This is despite the fact that all the installational features familiar with this engine are absent. Thrust of each engine with max augmentation is in the 25,000lb (11,340kg) class.
From the start the Su-24 was a top-priority project, with nothing whatsoever compromised. Design engineers were made up into the biggest team ever seen, including many drawn from Poland’s PZL, and in every detail the result is the very best that can be achieved. In many respects the Su-24 resembles the Tornado, though on a physically larger scale; it follows the F-111 in only one major feature: side by side seating for the pilot and weapon systems officer. Unlike the American machine it has half its heavy weapon load under the fuselage, and the way the doors over the bays for the twin-wheel main gears fold down towards each other is particularly neat, the large panels immediately in front of them (covering the unidentified internal items) being the airbrakes.
There is no doubt the max wing loading of the Su-24 is greater than in any other combat aircraft at some 180lb/sq ft (878kg/m2), and combined with the max sweep of 68° and near-absence of a fixed portion must result in outstandingly good buffet-free ride qualities in low-level missions at full power. In view of the totally uncompromised nature of this aircraft it is probable that the wing has a Mach/sweep programmer which continuously adjusts wing sweep, unlike the direct manual control needed on the Su-17/20/22.
Other airframe features include fully variable engine inlets, with auxiliary doors and ejectors; slender wings with full-span slats and double-slotted (at low speeds) and powered tailerons; a single vertical tail plus ventral fins at the chines of the wide flat-bottomed rear fuselage; and easily the best overall avionic fit seen on any tactical aircraft in service anywhere. Details are still the subject of speculation, and variations are already responsible for the so-far unexplained identification by NATO of three in service variants called “Fencer-A, -B, and -C". (All are believed to be side by side two seaters).
The main radar is unquestionably a pulse-doopler set of remarkable power and versatility. Terrain following capability is provided by secondary TFR sets as in the F-111, and a separate doopler navigation radar is on the ventral centerline. The entire aircraft is covered with avionics, most of them flush or served by very small chin fairing, what are believed to be CW illuminators for radar missile guidance are ahead of the wing gloves on the top sides of the inlets, and the tail is a forest of flush aerials and small pods or blisters, varying from one aircraft to another.
It is probable that the internal EW/ECM suite is more comprehensive than in any other supersonic aircraft, though details are still being investigated by Western analysts. There is not the slightest doubt that the entire avionics installation was designed in parallel with the aircraft itself, and when any particular item was missing or unsuitable it was created from scratch.
Not least of the curious things about this ultra-important aircraft is that the dimensions given above were published in the West as estimates in 1974, when virtually nothing was known about what at that time was thought to be the “Su-19”. They have never been altered, though their seeming exactness is questionable. NATO analysts have been franker when it comes to identifying the two ventral blisters, which cover permanently installed equipment. Both are probably guns, but of different types, in conformity with Soviet policy for use against different classes of target, but the official view is that only the left installation is a gun, the right-hand one being unidentified.
Below: Sukhoi Su-24 “Fencer” nuclear-capable, all-weather flighter bomber of the Soviet Air Force. The very large fuel pods are attached to the fuselage (rather than to underwing pylons) adding to the already considerable range.
In 1984 the number of Su-24s in service was believed to be 800. They are serving in all peripheral Military Districts of the Soviet Union, the main concentration being in Europe but over 200 being around China and on the Pacific coastal areas. The two giant Su-24 forces are the 4th Air Army (Hungary and the Ukraine) and the 24th Air Army (Poland), each of which has five Su-24 polks (regiments) with 60 inventory aircraft apiece.
The three versions “Fencer-A, -B and C” have not yet been described, but the most recent was only developed in 1981. According to the US DoD, some Su-24s are now being assigned to the ADD (long-range aviation) strategic force, “and the number assigned to this task is likely to increase by 50 per cent over the next few years.
A recent traveler to Riga Airport Soviet Union, reported seeing rows of completely unpainted Su-24s obviously in combat service.
Sukhoi Su-25 “Frogfoot”
Origin: Soviet Union.
Type: Close-support attack and Co-In aircraft.
Engines: Two turbojets or turbofans (see below).
Dimensions: (estimated Span 50·83ft (15·5m); length 47·5ft (14·5m); height 16·75ft (5·1m); wing area 400sq ft (37m2).
Weights: (estimated) Empty 17,000lb (7,700kg), loaded (forward airstrip) 28,000lb (12,700kg); (max) 36,050lb (16,350kg).
Performance: (estimated) Max speed (SL, clean) 546mph (880km/h); field length (forward airstrip weight) 3,300ft (1,000m); combat radius (conditions not specified) 345 miles (556km).
Armament: At least one gun is mounted, including a large multi-barrel cannon in a long chin fairing; other stores are carried on ten underwing pylons, total weight being put at 8,820lb (4,000kg).
Development: Many of the latest Soviet combat aircraft to enter service seem to have been inspired by US prototypes, and in this case the similarity to the Northrop A-9A (losing finalist in the AX competition) must be more than coincidental. Winner of the AX was the Fairchild A-10A, and by comparison with this the Su-25 is significantly smaller and lighter, but it has roughly similar power is the same: attacks on ground targets in close support of friendly ground forces, with particular capability to take out heavy armour, fortifications and similar well protected targets. The design is thus biased in favour of short field length, independence of ground services, good low-level manoeuvrability and a high degree of immunity to ground fire up to about 23mm caliber.
Since 1982 small numbers of Su-25s – which curiously have a fighter (odd-number) designations, despite having little pretension to air combat capability – have seen much action against the Mujaheddin in Afghanistan, who have commented on its long flight endurance at low level. It has operated with heavy bombs, very large numbers (a theoretical maximum of 320) of rockets and at least one high-velocity gun, and has often collaborated with Mi-24 “Hind-D” helicopters in making carefully combined attacks on the same target.
Though some dozens, if not hundreds of Su-25s are in FA service, USAF official commented in late 1983 that the type had still not been committed to full production. Yet the 1984 edition of the DoD review, Soviet Military Power, reported that Su-25s were coming off the production line at Tbilisi, Further, in June 1984 a Pentagon briefing, based on DIA assessments, reported that the Su-25 was one of the major current programmes, along with the MiG-29 and MiG-31.
In the 1983 edition of the same publication a detailed artist’s impression of the Su-25 appeared, showing stumpy wings without tip pods, a humpbacked body with low cockpit flush with the upper line, and a very short nose with a large radar. As all these features are totally at variance with the actual aircraft it is difficult to comment on such things as avionics fit.
Above: Su-25 “Frogfoot” in action in Afghanistan. Ten wing pylons are available for bombs or rocket pods, and a 30mm cannon is mounted internally. By early 1985 the Su-25 was also in Czechoslovakian service.
Available photographs confirm the long-span wing, tapered on the leading edge, for good STOL performance and long loiter endurance, high-mounted cockpit giving a good all-round view, dorsal spine leading to a delta-shaped fin, long down sloping nose (almost certainly without radar but with other surface-attack sensors) and wingtip pods which certainly are not mere antiflutter bodies. The engine bulges slope down from front to rear.
Sukhoi Su-27 “Flanker”
Origin: Soviet Union.
Type: Long-range multirole fighter.
Engines: Two augmented turbofans each in 28,000lb (12,700kg) thrust class.
Dimensions: (estimated) Empty 33,000lb (15,000kg); internal fuel 14,330lb (6,500kg); loaded (air to air mission) 49,600lb (22,500kg), (max, surface attack) 72,200lb (35,000kg).
Performance: (estimated) Max speed (hi, air to air mission) 1,350kt (DoD figure, converting to 1,555mph/2,500km/h, Mach 2·35); combat radius (air to air mission) 715 miles (1,150km).
Armament: Eight AAMs of various types including AA-X-10; probably at least one internal gun.
Development: Biggest and most powerful Soviet fighter apart from the MiG-25/31, the Su-27 is based on the same aerodynamics as the MiG-29, which in any case certainly owes much to the current crop of US fighters. Compared with the MiG-29 the Su-27 is almost exactly twice as big (in area terms, ie a 1·4 linear scale); twice as heavy and twice as powerful. Various analyses have been published since mid-1983, the figures above being based on those issued by the US DoD in March 1984. They show an aircraft significantly larger than November 1983 DoD estimates, but with slightly less engine thrust and lower weights. Whether the 1983 estimates for turn rate - 17°/s at Mach 0·9 at 15,000ft/4,572m sustained, and 23°/s peak instaneous value – have since been subjected to revision has not been made public.
Despite its size, accepted in order to achieve long mission radius with many weapons, giving great persistence in air combat, the Su-27 is generally considered to be able to outfly the MiG-29, which itself was specifically designed to beat the F-14, F-15, F-16 and F-18 in close combat (and is generally accepted as doing so, the F-16 being the most difficult opponent in these circumstances). It is difficult to win by copying, and there is no question that the Soviet designers have carefully studied the US fighters before drawing the first line on paper, but with today’s engines the US fighters are almost certainly unable to stay with the Su-27, which had the massive advantage of being stated when the F-14 and F-15 were already flying. Obviously the Su-27 has a completely new pulse-doppler multimode radar with the greatest possible performance against low flying targets.
What is much more serious than all the foregoing is the Su-27’s armament. Not only is it now estimated – or known, because the information is published as fact – that this fighter carries eight AAMs, but they are partly or wholly of the AA-X-10 type. This is the first Soviet AAM which, in its radar-guided version, has its own active seeker. Thus it can be fired against a distant hostile aircraft in the desired “fire and forget” manner, the Su-27 then either engaging other targets or turning away. There is no need to keep flying towards the enemy in order to illuminate the target with the fighter’s own radar. The X-10 flies on strapdown inertial guidance until its own active radar switches on and locks-on to the target. This capability will not arrive in Western squadrons until the AIM-120A (AMRAAM) becomes operational in, it is hoped, 1986. The Soviet X-10 is part of the Su-27 weapon system which is already in preliminary service and was expected to be declared operational in spring 1984. It includes an IR search/track system and magnifying optics.
Above: The Su-27 “Flanker” has the power to outfly the latest American fighters, and the formidable AA-X-20 missile.
The aircraft may have a blended wing/body form, and as the inlets cannot be seen from above because of the long leading-edge root extensions available information on them is largely speculative. The wing is well aft, the fins are vertical and overlap the wing and tail-planes, and the latter do not extend aft of the nozzles as in the MiG-29. How the eight AAMs, or DoD announced alternative of 12 bombs, are carried is not yet clear; there is no room to get more than two bombs in tandem in tangential carriage on the fuselage, and the inevitable answer must include high-drag wing pylons.
There is probably a tandem two-seat Su-27, and probably a reconnaissance pod or pallet can be carried. This aircraft is reported by the DoD to be in production at Komsomolsk, in the Far East.