Sukhoi S-37 (Su-37) Multirole Canard Delta

[overscan (PaulMM)]

A resolution was passed by the Communist Party in 1989 tasking Sukhoi with developing a conceptual design of a multirole fighter-bomber.The S-37 was a single engine canard delta (single and twin seat versions were studied) designed to replace the Su-7/-17, Su-25, MiG-21, MiG-23 and MiG-27 aircraft in VVS service and for export to friendly nations. The latest "AirLand Operation" doctrine called for CAS (Close Air Support) as deep as 150km beyond the front lines. The task for the S-37 was to destroy surface static and mobile targets, air defence systems, perform reconnaissance missions, plus destruction of enemy aircraft and helicopters.

Chief designer on the project was Vladimir Babak, and operational experiences with the Su-17 and Su-25 in Afghanistan were taken on board in the design. To reduce the time and costs of designing and producing the S-37, it was planned to use existing systems, or those already under development for other new aircraft. A fly-by-wire control system allowed relaxed static stability.

The avionics suite included a multimode radar (possibly based on N010 Zhuk) and an underfuselage optronic system (resembling the SU-24M's Kaira), with a built in "Pastel" RWR for warning and ARM targeting and ECM pods on the wingtips (Sorbstiya). The initial design used the R-79 engine, already used on the Yak-41M, with the thrust vectoring nozzle removed, possibly to be replaced by AL-41F later on.

Up to 800kg of armour was included to protect the pilot, engine and other critical airframe components. 17 hardpoints (9 underfuselage and 8 under the wings) allowed carriage of a the whole spectrum of available weapons. According to Yefim Gordon a single GSh-30 cannon was mounted in the starboard wing root, but this isn't clearly visible on the display models.

Wings had folds to reduce ground footprint.

Unfortunately, the collapse of the Soviet Union brought funding to a halt. Sukhoi had touted the project in 1991 to foreign countries, looking for a partner to invest the money needed, but were unsuccessful. The new Russian airforce were also unhappy with the single engine design. Babak's team worked for some time on a new project "237" modified to use twin engines, the status of which is currently unknown.

S-37 Project

Length: 17.65m (Bedretdinov), 17.5m (Butowski)
Wingspan: 12.08m (Bedretdinov), 11.8m (Butowski) (8.64m folded)
Wing Area: 50 sq m
Height: 5.74m

Maximum speed: 1500km/h at low level, Mach 2.0 at height
Maximum altitude: 17000m
Range, 3000kg payload: 800km (low level) 1,500km (high level)
G load: +9/-3g
Supersonic G load: 8g
Acceleration from 600km/h to 1100km/h at 1000m altitude: 14 secs
Acceleration from 1100km/h to 1300km/h at 1000m altitude: 7.2 secs

Engine: 1 x R-79M turbofan
Thrust: 18,143kg

Weight, Maximum: 24,970kg
Weight, Normal takeoff: 16-18,000kg
Weight, empty: 12000kg
Internal fuel capacity: 8,300kg
Normal combat payload: 5000kg
Maximum combat payload: 8000kg

Sources

• Piotr Butowski Lotnictwo Wojskowe Rosji Tom 1, Lampart, 1995
• Ildar Bedretdinov The Attack Aircraft Su-25 and its derivatives, B & Co, 2002
• Tony Buttler & Yefim Gordon Soviet Secret Projects: Fighters since 1945 Midland Counties, 2005

 

[TinWing]

Wings had folds to reduce ground footprint.

In the instances where carrier based aircraft were purchased for land based service, wing folds have indeed been retained "to reduce ground footprint."

However, I can't think of a single instance where wing folds have been incorporated into a land based combat aircraft.

S-37 Project

Length: 17.65m (Bedretdinov), 17.5m (Butowski)
Wingspan: 12.08m (Bedretdinov), 11.8m (Butowski) (8.64m folded)
Wing Area: 50 sq m
Height: 5.74m

Maximum speed: 1500km/h at low level, Mach 2.0 at height
Maximum altitude: 17000m
Range, 3000kg payload: 800km (low level) 1,500km (high level)
G load: +9/-3g
Supersonic G load: 8g
Acceleration from 600km/h to 1100km/h at 1000m altitude: 14 secs
Acceleration from 1100km/h to 1300km/h at 1000m altitude: 7.2 secs

Engine: 1 x R-79M turbofan
Thrust: 18,143kg

Weight, Maximum: 24,970kg
Weight, Normal takeoff: 16-18,000kg
Weight, empty: 12000kg
Internal fuel capacity: 8,300kg
Normal combat payload: 5000kg
Maximum combat payload: 8000kg

Sources

• Piotr Butowski Lotnictwo Wojskowe Rosji Tom 1, Lampart, 1995
• Ildar Bedretdinov The Attack Aircraft Su-25 and its derivatives, B & Co, 2002
• Tony Buttler & Yefim Gordon Soviet Secret Projects: Fighters since 1945 Midland Counties, 2005

Some of these specifications are quite new and surprising.

An internal fuel capacity of 8,300kg is quite exceptional.

For the sake of comparison, the contemporary Dassault Rafale has an internal fuel capacity of only 4,500kg.

 

[overscan (PaulMM)]

I'm inclined to not believe the figure for internal fuel. Its not far off the 10,000kg maximum for the Su-27, a substantially larger aircraft. Additionally, the empty weight (12,000kg) + Max Payload (8000kg) + Max Fuel (8300kg) comes to way more than 24,970kg MTOW.

If the 16,000-18,000kg figure for normal takeoff from Piotr Butowski is anywhere near accurate, then even going for 18,000kg gives just 6000kg usable load. A more believable breakdown might be ~1000kg payload, ~5000kg fuel. Then 12000+5000+8300 = 25,300kg, which is pretty close to the MTOW quoted.

Therefore 8300kg is wrong. Maybe its maximum fuel load, internal+external?

The figures certainly dont add up.

 

[overscan (PaulMM)]

How about - 25000kg MTOW, which is made of 5000kg payload, 8300kg fuel. That makes empty weight a bit under 12000kg, and means that to carry 8000kg payload it would have reduce fuel load to 5300kg.

Hmmm....

 

[TinWing]

Source:

Jane's All The World's Aircraft, 1992-93

 

[TinWing]

Source:

The Osprey Encyclopedia of Russian Aircraft, by Bill Gunston.

 

[overscan (PaulMM)]

Some more sources

Speed: Mach 1.8
Normal takeoff weight: 18000kg
Range: 1000km+ with 4000kg payload
1300kg in dedicated protection measures
Expected export cost: around $30 million
A production run of 1,000, exporting to 24 countries, was thought possible.

Volodin says "The solution about the realisation of project was accepted in 1990 g. All necessary documentation for the building was sent to the series plant".

Source

• Vyacheslav Volodin (GosNIIAS) The development of first Russian JSF was interrupted in 1991 The Herald of Aviation and Cosmonautics № 1, 2001

 

[TinWing]

1300kg in dedicated protection measures

How is the term "dedicated protection measures" defined? The figure of 800kg of "armor" was originally quoted in Jane's.

Expected export cost: around $30 million

This Soviet-era figure is not inconsiderable by the standards of 1990.

By the middle of the decade, the going price of the Su-27 (for customer such as China and Vietnam) was in the neighborhood of $33 million USD.

Volodin says "The solution about the realisation of project was accepted in 1990 g. All necessary documentation for the building was sent to the series plant".

This quote is very surprising. Which production facility was assigned to this project?

 

[overscan (PaulMM)]

The mass of the means of the guaranty of combat life was about 1,3 t (more than 7% normal takeoff mass of aircraft)

He doesn't say, but other articles mention armour for the pilots, fire-retardant foam in the fuel tanks, etc.

The wide marketing analysis, carried out by developers, showed that potential buyers Su-37 on the outside market can be 24 countries of peace. Up to the moment of making a decision about building of experimental aircraft the capacity of preliminary orders from other countries composed 1000 units. (This value of the same order as and the export program of deliveries JSF in 2000 units, accepted as the condition for the transition to the full-scale development of aircraft). Some VVS alone of China gave preliminary claim for 180 aircraft.

The interest of foreign clients in the developed aircraft was the best index of the prospect of the developed project. To this interest contributed not only the unique characteristics of functional “face” of aircraft, but also the assumed comparatively low cost Su-37 on the market. According to the preliminary evaluations, the price of aircraft should not have exceeded 30 mln. dollars.

I assume production would have been at the Su-25 plant in Tbilisi, but noone has mentioned this.

Some more data, from the 1991 promotional materials;

MTOW: 25000kg
Payload: 8000kg
R-79 Engine: 18,500kg thrust
Canard deflection: +10/-70 deg
landing speed on approach 250-260 km/h, 220 km/h at contact.

Source
Aviation Week and Space Technology, 1991 Vol135, No19

 

[overscan (PaulMM)]

From Koku-Fan, Feb 1992

 

[paralay]

Su-37 it « Лёгкий фронтовой истребитель » (Easy front fighter
), it{he} was competitor MiG - LFI (412).

Weight of fuel of 30 % of the maximum weight, too at Su-27.
Su-27: 9400 kg / 30300 kg = 0.31
Su-37: 25000 kg * 0.31 = 7755 kg is really.

Weight Su-27:
Computational flight weight of 21400 kg (air-air)
Take-off mass, kg:
Maximal{Maximum} 30300 - 33000 kg (Su-27SK)
Normal 23650 kg (0,78)
Computational (2Р27+2Р73Э, fuel 5090 kg) 23250 kg (Su-27SK)
(2Р27+2Р73Э, fuel 9220 kg) 27380 kg (Su-27SK)
Landing weight:
Limiting{Marginal} 23000 kg
Maximal{Maximum} (2Р27+2Р73Э, fuel = 2840) 21000 kg
Maximal{Maximum} (without rockets, fuel =3560 kg) 21000 kg

Weight of the empty equipped airplane 16380 kg. (0,54)

Fuel 9400 kg (0,31)/ 5270 (0,174)
Computational "air-air" 5090 kg
The basic{main} "air-ground" 4970 kg

Battle{Dashing} load, kg 6000 kg (0,2) / 2000 (0,065)
Maximal{Maximum} "air-air" 1950 kg

 

[overscan (PaulMM)]

Couple more pics found trawling the net

 

[hs1216]

WOW. The S-37 looks like a Gripen on steroids. With that much capability in one plane, it could have been a export success. Are there any other pictures of it.

 

[hs1216]

So there are no other photos or pictures of this amazing aircraft? I got to beileve there are photos at different angles of the very same model or models. So does anyone out their got any more!!!

 

[overscan (PaulMM)]

Rest assured if I find any I will post them! One of my favourite designs, and Antonov (Su-27 preliminary designer) rated it highly too.

 

[hs1216]

Thank you so much.

 

[rousseau]

Maybe the J-10 were from this

 

[hs1216]

Maybe the J-10 were from this

While that is certainly a change from the usual J-10/Lavi argument, the J-10 is nether derived or based on the S-37 design. The S-37 is larger, has D shaped side intakes, heavily blended airframe, and is designed as a ground attack aircraft first Air superiority second. While the J-10 has a boxy chin inlet, not as blended, and is primarily a air-superiority fighter. However the delta wing of the S-37 is surprisingly similar to the J-10’s.

 

[overscan (PaulMM)]

Better version of pic

Source:
Aerosvet June 1991

 

[overscan (PaulMM)]

Pics from Aviation Week, November 11 1991

 

[T-50]

Best people
has someone new artist inpressions of the Su S-37 single engine aircraft(not de Su-37 Flanker!)
or new released photos of the model or mock up? it was an project for a multirole combat aircraft in the class of the Rafale or Gripen.
This project was led by mr Babak and was canceled by+1990s,i believe there was a mock up
of this aircraft
greetings T-50

 

[Deino]

Just as easy as Google: the third button on top is the "SEARCH" function ...

and here You go:

http://www.secretprojects.co.uk/forum/index.php/topic,94.0.html

Cheers, Deino

 

[overscan (PaulMM)]

According to Babak, some windtunnel tests and avionic and engine component tests have been made

Flug Revue, 1992, possibly Issue 8 (?)

 

[boxkite]

According to Babak, some windtunnel tests and avionic and engine component tests have been made

Flug Revue, 1992, possibly Issue 8 (?)

Quote was in FlugRevue 1/1992 (page 62)

 

[T-50]

the naval model is realy cool its a shame that the Russian airforce wont have it!
It was a promesing project,are there more pics of the naval model?

 

[T-50]

Hello guys i saw on the Russian site http// www.paralay.com a picture of probably a further developed version of the S-37.
It has a flattened nose,has someone info about this version? the model was designated Su-137
thanks in advance
T-50

 

[overscan (PaulMM)]

This picture?

No idea of the source. Looks pretty similar. Supposedly there was a 237 with twin engines.

 

[T-50]

Yep that's the picture! it looks like somebody was sitting on the nose!
and a two engined version dubbed the Su-237? it can be a logical step ! but I've never reed about such a project.
Only Mr Babak knows it because he was chief designer on this project
cheers T-50

 

[overscan (PaulMM)]

Yes, I think it was Piotr Butowski who mentioned that work did continue on a twin RD-33 engined version dubbed 237.

 

[T-50]

In which book have you read it,that Piotr Bitowsky mentioned the 2 engined variant?
Are there drawings of the Su-237? its a pitty that they never developed this aircraft!
cheers T-50

 

[overscan (PaulMM)]

No drawings. One line mention in an article on Russia's advanced combat aircraft.

 

[Triton]

Sukhoi Su-37 (1992)

Type: Single-seat and/or two-seat multi-role combat aircraft.

Program: First shown in model form at late 1991 trade shows, including Dubai '91; some wind tunnel tests completed; at basic design stage in 1992; foreign partner then being sought for development.

Design features: Single-seat or tandem two-seat compound delta configuration, with close-coupled foreplanes; wings fold for stowage in minimal space; engine air intakes beneath root of each foreplane leading-edge, with curved leading edge extension forward of the top lip of intake; survivability features include 800 kg (1,765 lb) of armor to protect pilot, power plant, and critical airframe components, and reticulated foam to protect fuel system and tanks; specification based on Su-25 experience in Afghanistan, called for transonic low-level attack performance, high agility and degree of low observability impracticable with large podded engines.

Flying controls: Fly-by-wire; sweptback foreplanes controllable +10/70 degrees, wing trailing-edge evelons, leading edge slats, and rudder.

Landing gear: Retractable tricycle type; twin nose wheels, single main wheels; minimum runway hardness 7-8 kg/sq cm (110-114 lb/sq in).

Power plant: One Soyuz/Tumansky turbofan, 180 kN (40,500 lb st) with afterburning; provision for flight refueling probe.

Accommodation: Pilot only or crew of two in tandem, on ejection seats in armored cockpit.

Avionics: Radar in nose, offering low-altitude terrain following and terrain avoidance at transonic speed, attack guidance against land and sea targets, simultaneous tracking of ten targets, and location, tracking, and fire control functions against low-flying targets at all speeds, including hovering helicopters in surface clutter; laser range finder and target designator, including rear-ward designation; laser and radar warning systems; chaff/flare and other decoys; podded multi-channel thermal imaging system for 58 nm (100-150 km; 62-93 mile) standoff attack range; cylindrical ECM jamming pod (approx. 4 m; 13 ft 1.5 in long) on each wing tip.

Armament: One 33 mm GSh-30 gun in starboard wingroot extension; ten underfuselage and eight underwing attachments for laser and TV guided air-to-surface missiles, anti-radiation missiles, 16 anti-tank missiles, pods of 85 to 370 mm rockets, retarded and conventional bombs up to 1,500 kg and podded 30 mm guns.

Equipment: Optional photographic, infra-red, and TV reconnaissance pods.

Dimensions external
Wing span: 11.80 m (38 ft 8.5 in)
Wing span, folded: 8.10 m (26 ft 7 in)
Length overall: 17.50 m (57 ft 5 in)

Weights and loadings
Max fuel load: 8,300 kg (18,300 lb)
Max external stores: 8,000 kg (17,630 lb)
Normal T-O weight: 16,000-18,000 kg (35,275-39,680 lb)
Max T-O weight: 25,000 kg (55,115 lb)

Performance (estimated)
Max level speed at height: Mach 2 class
Max level speed at sea level: Mach 1.22 (810 kts; 1,500 km/h; 932 mph)
Approach speed: 135-140 knots (250-260 km/h; 155-162 mph)
Touchdown speed: 119 knots (220 km/h: 137 mph)

Time to accelerate at 1,000 m (3,300 feet) from 325 to 595 knots (600 to 1,100 km/h; 370 to 685 mph): 14 s

Time to accelerate at 1,000 m (3,300 feet) from 595 to 700 knots (1,100 to 1,300 km/h; 685 to 807 mph): 7 s

Service ceiling: 17,000 m (55,775 ft)
Nominal combat radius with 3,000 kg (6,615 lb) stores: 810 nm (1,500 km; 932 miles)
g limits: +9/-3
Maneuvering limit at supersonic speed: +8 g

Source: Lambert, Mark ed. Jane's All the World's Aircraft 1992-1993 Jane's Information Group Ltd. 1992 p. 244.

 

[Triton]

Sukhoi S-37 (Su-37) multirole canard delta from USSR-Russian Aviation & Space Collectibles (Alex Panchenko).

Description:

12" length resin model from Sukhoi Design Bureau. Can be displayed on own wheels or on base with engraved `CY` (Sukhoi) logo. Blended wing/body with quarter-round inlets under LERX carrying foreplanes driven +10/-70 degree, other FBW controls slats/elevons/rudder. Incorporated Su-25 Afghan lessons to maximize survivability. Terrain-following radar (10-target capability), thermal imager, laser ranger/designator (front/rear). EW/IRCM (jammers on wingtips), retract FR p[robe, gun in right wingroot. Aircraft able to carry up to 8 tones (17,637 jb) weapons on 18 attachments. Two-seat and naval versions intended., but reported canceled in 1994.

Source:
http://www.ussr-airspace.com/index.php?main_page=product_info&cPath=28_39_38_97&products_id=1269

 

[Pioneer]

Thanks very interesting!!

Incorporated Su-25 Afghan lessons to maximize survivability.

In a way the S-37 design conception/philosophy somewhat reminds me of the Fairchild-Republic FX (F-15) design proposal - in that Fairchild Republic incorporated its combat lessons and short falls of its Republic F-105 - especially survivability redundancy into its FX design!
Although I must say I am very surprised Sukhoi went for a single engine arrangement!! ???

Thanks again

Regards
Pioneer

 

[redstar72]

Although I must say I am very surprised Sukhoi went for a single engine arrangement!! ???

It would be a successor of the Su-17/22, which also was single-engine. So, nothing unexpected for me..

 

[gral_rj]

Although I must say I am very surprised Sukhoi went for a single engine arrangement!! ???

IIRC, there were studies of a twin-engined derivative of the Su-37, using RD-33s; I don't think any picture of it exists though.

 

[Stargazer]

Yet another three-view of the single-seat version of the first S-37 project, from the Polish PKL #40:

 

[T-50]

I know ther was a fullscale mockup of the S-37 been build, are there any photos of the mockup?

 

[Stargazer]

From the Fall 1998 issue of World Air Power Journal (I enhanced the scan and changed the lettering):

 

[flateric]

I just wonder what Babak's S-37 do in that row)))