The MAS SB-4 Corona is a supersonic stealth variable geometry nuclear powered global range strategic bomber designed primarily for the ZMAF strategic bomber command. It was procured specificity to fill the mission role of targeting and destroying air defense facilities and SDI ground sites with smart black body bombs. The concept of the Corona like most stealth bombers is to carry out a massive strike within the enemy aerospace defense network with limited or no warning as would be seen with conventional missile or bomber strikes and with a far lower cost per target via the use of black body smart bombs and far higher loiter time than the stealth ICCMs presently being fielded by the ZMSF or other similar organisations. Corona has capacities which therefore effectively surpass those of the somewhat dated but still highly robust Type 1000 but at a far greater per unit cost.
The Corona in essence is designed in regular service to fill a complimentary role to ZMAFs extensive Type 1000 bomber force. The SB-4 was initially proposed in 1994 with the prerequisites of a smaller airframe, payload, greater or equivalent speed and performance and above all else a stealth compared to its much older cousin.
The stealth capacity the Corona was designed primarily for its sub sonic role and is only projected to be effectively employed for deep penetration against a first world standard air defence network in said subsonic mode given the now permanent fielding of high gain infra red systems in multiple network centric platforms. Her outer very high capacity carbon based counter radar coating is designed to ablate away when she exceeds Mach 2. To aid her in avoiding infra red detection her primary out-takes are fitted with extensive cooling ducts especially given the high initial output temperature resulting from her nuclear drive compared with conventional combustion engines. This duct arrangement precludes the use of 4d thrust vectoring and thus the Corona has only 2d horizontal thrust vectoring capacity (though some models are not fitted with this and in its place is a more extensive rearward mounted ECM suite). Given this fact and given the prior less than satisfactory performance of the type 1000 in sub sonic manoeuvring the SB-4s airframe was specificity designed to allow it a maximum of sub sonic maneuverability via its inherently unstable “relaxed stability” design.
In conjunction with variable forward swept wing and canards the Corona is effectively unflyable without its extensive General Data Technologies Air Advantage 40 networked fly by light fibreless system. This system is a “carefree “ which does not permit the pilot to exceed the airframes tolerance levels. The Air Advantage 40 relies on optical ducts throughout the aircraft which are integrated into the airframe instead of fibre channels or conventional fly by wire. The system has a total of fifteen dedicated independent capable flight computer nodes which communicate to the hydraulic or electrical servo flight controls via direct laser data input. Each dedicated node is fully capable of handling the air crafts complete combat flight workload and each with a four hour emergency lithium ion independent power source which can be manually recharged in six of the repeater units cases via a set of terminals and a hand driven generator.
The Corona features a relatively lightweight construction of a 48% titanium boron alloy, 62% composites (34% heat treated carbon fibre composites + 28% reinforced glass) airframe.
Roll control is primarily achieved by use of the wing flapperons. Pitch control is by operation of the canards and flapperons, the yaw control is by rudder and thrust vectoring surfaces are moved through four independent hydraulics systems that are incorporated in the aircraft, which also supply various other items, such as the canopy, brakes and undercarriage (the undercarriage is equipped with a single use emergency explosive deployment mechanism that essentially consists of a blasting cap and small shaped charge at the end of the primary hydraulic tubes and locking mechanisms). One 7000 psi engine-driven gearbox powers each system.
The SB-4 is propelled by two SCAPA Mk.XIV Damocles nuclear thermal jets which each produce 2100 kilo Newton’s of thrust. Within the Damocles XIV there is a variable shock cone to slow inbound gas to acceptable speeds or open to allow her sub sonic flight electricaly driven intake turbines maximum input, the air then is forced over a canister containing gaseous nuclear fuel. The canister is made out of a super-high-temperature quartz container, over which the air flows. It is a closed cycle engine limited by the critical temperature of quartz instead of the fuel stack and capable unlike the The Type 1000s Mk.IIIs of zero speed start. Although less efficient than an open-cycle design, the closed-cycle design delivers a rather respectable specific impulse and does not emit a radioactive "hot" exhaust which would be highly detrimental to the environment. The jet is optimised to operate at Mach 2.1 to Mach 3.2.
The primary radiation shielding is set forward of the reactor pod to give maximum protection to the flight crew who's flight suits do not require any special augmentation. While it is safe upon the ground and safe for the flight crew in flight the aircraft's radiation cone is unsafe to approach when in maximum reactor output / supersonic flight from outside the aircraft without extensive shielding. The reactor pods are jetisonable as one module along with the primary shielding array. This reactor pallet is designed for impacts from 18,000 metres without retardation and has integrated ribbon chutes for use above that height. On release from the aircraft the reactor module auto scrams unless it is linked to the specialist service vehicle or hanger service cradle.
All Coronas are equipped with both a full digital flight environment and a conventional digital glass cockpit. In addition to its extensive computer aided display systems a more conventional electro-optical viewing system that uses platinum silicide forward-looking infrared is provided. Primarily however Corona pilots are trained to fly using the high resolution low-light-level multi channel multi input digital CCD based system is provided integrated into the digital flight environment augmented by real time LIDAR/LADAR (and if operating radar or external data flow) forward looking terrain scanning and global terrain and local, squadron or global battle space database's to assist in targeting, battle assessment, and flight safety, thus further improving its combat ability and low-level flight capability.
Corona is equipped with the MAS Vampire system. A large array of passive radio frequency mapping phased array receivers are mounted within the wings and with wing trailing extendible cable pods for increased baseline. These designed to use the local pre mapped and constantly locally updated high and low output radio and microwave sources as an effective passive scanning radar.
This system has an effective range and capacity in first world radio frequency pollution conditions in excess of 230 kilometres at maximum base line extension with AESA like performance at 80 kilometres and below. With the passive tracking of up to 220 targets using sources down to and including personal mobile phones as its output the Vampire gives corona a bleeding edge electronic warfare advantage. Coronas active radar system has an effective maximum range of 390 kilometres and is integrated into the Mas Vampire system receivers. The Corona has extensive multi pulsed targeting lasing capacity, along with both bounced and integrated relay man guided weapons control. The provision of two sysops allows a vastly increased number of targets to be engaged simultaneously.
The purely nuclear nature of the SB-4s drive system gives her a range limited only by crew endurance, or in the extreme, required maintenance. It has an un refueled recommended combat range in excess of 28,200 kilometres though this can be exceeded in theory with the warning that it will negate warranty. The nature of her drive system precludes mid air refueling and thus no system for this is in place and also precludes the use of a conventional afterburner. There have been trials with integrated liquid oxygen, hydrogen slush afterburner systems on modified airframes without thermal ducting and the airframe has been slated as a test bed for large scale SCRAM trials.
Crew: 4 (Captain, Co pilot/sysop, Co pilot/sysop, Nuclear specialist.
Length: 44 metres
Wingspan: 39 metres (max)
Height: 21 metres
Empty: (262,386 kilograms)
Loaded: (644,000 kilograms)
Maximum take-off: (713 kilograms)
2 X SCAPA Mk.XIV Damocles closed cycle Nuclear thermal jets; 2100 kilo Newton’s of thrust each.
Approximately (210,000 kilograms) mixed ordnance—bombs, cruise missiles (optionally on two external hardpoint mounts for ICCM or stealth shroud missile pod), mines, and various missiles in two internal bays.
Maximum speed: Mach 3.1
Range: 28,200 kilometres
Service ceiling: 22,300 meter
Rate of climb: 5200 m/min ()
RCS: 0.084 square metres (Sub sonicwith coating), 1.3 with external stealth pod mounts and 8 Square metres without coating at Mach 2+ speeds.
Independent cost reviews place the SB4 at approximately 7.9 billion NS dollars per aircraft.
MAS flight worthy test bed air frames (civilian) 5
ZMAF: 428 in service, seventy more budgeted for.
ZMSF: 53 in service, twelve more budgeted for. (3 system testbeds 50 ASAT, high altitude warfare modified)
ZMN: 2 in service (system test beds)
INT-SEC: 10 in service (modifications for ram air personnel carrying glide pod deployment on at least three, extensive ECM loads)
Production is located in the Barsin County secure military production zone in the MAS Nine River Valley facility in the ZMI home territory, theoretical maximum output is 1300 units per year.
The SB4 corona has of yet not been exported.