Lockheed S-3 Viking

Le Lockheed S-3 Viking vu sur Wikipedia.fr .Merci

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Le [Vous devez être inscrit et connecté pour voir ce lien] S-3 Viking est le successeur du [Vous devez être inscrit et connecté pour voir ce lien].

C'est un avion compact, propulsé par deux réacteurs situés dans des nacelles sous les ailes, et qui depuis la fin de la Guerre froide joue un rôle important dans la lutte sous-marine et la détection des mines.

Il est de surcroît armé de toute une panoplie de missiles air-surface.

Depuis le retrait de l'[Vous devez être inscrit et connecté pour voir ce lien] des [Vous devez être inscrit et connecté pour voir ce lien], il devient également le principal ravitailleur en vol des avions de
l'Aéronavale, car la version S-3B est équipée pour ce rôle.

Il existe des variantes US-3, équipées de 6 sièges et utilisées pour le transport, ainsi que ES-3, dédiées à la guerre électronique.

Il est équipé du [Vous devez être inscrit et connecté pour voir ce lien].

Je saute directement à la version de langue anglaise Wikipedia.en traitant du S 3

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The Lockheed S-3 Viking is a four-seat [Vous devez être inscrit et connecté pour voir ce lien] that was used by the [Vous devez être inscrit et connecté pour voir ce lien] to identify and track enemy submarines.

In the late 1990s, the S-3B's mission focus shifted to surface warfare and aerial refueling.

The Viking also provided electronic warfare and surface surveillance capabilities to the carrier battle group.

A carrier-based, subsonic, all-weather, multi-mission aircraft with long range, it carried automated weapon systems, and was capable of extended missions with [Vous devez être inscrit et connecté pour voir ce lien].

Because of the engines’ low-pitched sound, it was nicknamed the "Hoover" after the [Vous devez être inscrit et connecté pour voir ce lien] brand.

The S-3 was retired from front-line fleet service aboard aircraft carriers by the US Navy in January 2009, with its missions being assumed by other platforms such as the [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien], and [Vous devez être inscrit et connecté pour voir ce lien]. Several examples continue to be flown by Air Test and Evaluation Squadron THREE ZERO (VX-30) at [Vous devez être inscrit et connecté pour voir ce lien], California for range clearance and surveillance operations and a single example is operated by the [Vous devez être inscrit et connecté pour voir ce lien] ([Vous devez être inscrit et connecté pour voir ce lien]) at the NASA [Vous devez être inscrit et connecté pour voir ce lien].

Development



In the mid-1960s, the U.S. Navy developed the VSX (Heavier-than-air, Anti-submarine, Experimental) requirement for a replacement for the piston-engined [Vous devez être inscrit et connecté pour voir ce lien] as an anti-submarine aircraft to fly off the Navy's aircraft carriers.

In August 1968, a team led by Lockheed and a [Vous devez être inscrit et connecté pour voir ce lien]/[Vous devez être inscrit et connecté pour voir ce lien] team were asked to further develop their proposals to meet this requirement.

Lockheed recognised that it had little recent experience in designing carrier based aircraft, so [Vous devez être inscrit et connecté pour voir ce lien]
(LTV) was brought into the team, being responsible for the folding wings and tail, the engine nacelles, and the landing gear, which was derived from [Vous devez être inscrit et connecté pour voir ce lien] (nose) and [Vous devez être inscrit et connecté pour voir ce lien] (main).

[Vous devez être inscrit et connecté pour voir ce lien] Federal Systems was assigned the task of developing the aircraft's onboard computers which integrated input from sensors and sonobuoys.

On 4 August 1969, Lockheed's design was selected as the winner of the contest, and eight prototypes, designated YS-3A were ordered.

The first prototype flew on 21 January 1972 and the S-3 entered service in 1974. During the production run from
1974 to 1978, a total of 186 S-3As were built.

The majority of the surviving S-3As were later upgraded to the S-3B variant, with sixteen aircraft converted into ES-3A Shadow electronic intelligence (ELINT) collection aircraft.

ES-3A Shadow



The ES-3A Shadow was designed as a carrier-based, subsonic, all-weather, long-range, electronic reconnaissance ([Vous devez être inscrit et connecté pour voir ce lien]) aircraft. All 16 aircraft were modified S-3 Viking [Vous devez être inscrit et connecté pour voir ce lien], which were modified with numerous additional antennas and antenna housings. The Shadow replaced the [Vous devez être inscrit et connecté pour voir ce lien], and entered fleet service in 1993.

The ES-3A carried an extensive suite of electronic sensors and communications gear, replacing the S-3’s [Vous devez être inscrit et connecté pour voir ce lien],
armament, and maritime surveillance equipment with avionics racks
accommodating the ES-3A’s sensors. These modifications had minor impact
on [Vous devez être inscrit et connecté pour voir ce lien], reducing its top rated speed from 450 KTAS to 405 KTAS but had no noticeable impact on the aircraft's [Vous devez être inscrit et connecté pour voir ce lien]
and actually increased its rated loiter time. Because these aircraft
were standoff indications and warnings platforms and were never intended
to be part of an ingress strike package, this new speed limitation was
considered insignificant.

Design

The S-3 is a conventional [Vous devez être inscrit et connecté pour voir ce lien] with a high-mounted [Vous devez être inscrit et connecté pour voir ce lien], swept at an angle of 15°.

The two [Vous devez être inscrit et connecté pour voir ce lien] high-bypass [Vous devez être inscrit et connecté pour voir ce lien] engines mounted in [Vous devez être inscrit et connecté pour voir ce lien] under the wings provide excellent fuel efficiency, giving the Viking the required long range and endurance, while maintaining docile engine-out characteristics.


The aircraft can seat four crew members, three officers and one enlisted aircrewman, with the pilot and the copilot/tactical coordinator (COTAC) in the front of the cockpit and the tactical coordinator (TACCO) and sensor operator (SENSO) in the back.

Entry is by an entry door / ladder which folds out of the side of the fuselage.

When the aircraft's anti-submarine warfare (ASW) role ended in the late 1990s, the enlisted SENSOs were removed from the crew. In the tanking crew configuration, the S-3B typically flew with only a crew of two
(pilot and COTAC).

The wing is fitted with leading edge and [Vous devez être inscrit et connecté pour voir ce lien]. [Vous devez être inscrit et connecté pour voir ce lien] are fitted to both the upper and the lower surfaces of the wings.

All control surfaces are actuated by dual hydraulically boosted irreversible systems.

In the event of dual hydraulic failures, an Emergency Flight Control System (EFCS) permits manual control with greatly increased stick forces and reduced control authority.

Unlike many tactical jets which required ground service equipment, the S-3 was equipped with an [Vous devez être inscrit et connecté pour voir ce lien]
(APU) and capable of unassisted starts.

The aircraft's original APU could provide only minimal electric power and pressurized air for both aircraft cooling and for the engines' pneumatic starters.

A newer, more powerful APU could provide full electrical service to the aircraft.

The APU itself was started from a hydraulic accumulator by pulling a mechanical handle in the cockpit.

The APU accumulator was fed from the primary hydraulic system, but could also be pumped up manually (with much effort) from the cockpit.

All crew members sit on forward-facing, upward-firing Douglas Escapac [Vous devez être inscrit et connecté pour voir ce lien].

In "group eject" mode, initiating ejection from either front seat ejects the entire crew in sequence, with the back seats ejecting 0.5 seconds before the front in order to provide safe separation.

The rear seats are capable of self ejection, and the ejection sequence includes a pyrotechnic charge that stows the rear keyboard trays out of the occupants' way immediately before ejection.

Safe ejection requires the seats to be weighted in pairs, and when flying with a single crewman in the back the unoccupied seat is fitted with ballast blocks.

At the time it entered the fleet, the S-3 introduced an unprecedented level of systems integration.

Previous ASW aircraft like the [Vous devez être inscrit et connecté pour voir ce lien] and S-3's predecessor, the [Vous devez être inscrit et connecté pour voir ce lien], featured separate instrumentation and controls for each sensor system.

Sensor operators often monitored paper traces, using mechanical calipers to make precise measurements and annotating data by writing on the scrolling paper.

Beginning with the S-3, all sensor systems were integrated through a single General Purpose Digital Computer (GPDC).

Each crew station had its own display, and the COTAC, TACCO and SENSO displays were Multi-Purpose Displays (MPD), capable of displaying data from any of a number of systems.

This new level of integration allowed the crew to consult with each other by examining the same data at multiple stations simultaneously, to manage workload by assigning responsibility for a given sensor from one station to another, and to easily combine clues from each sensor to classify faint targets.

Because of this, the four-man S-3 was considered roughly equivalent in capability to the much larger P-3 with a crew of 12.

The aircraft has two underwing hardpoints that can be used to carry fuel tanks, general purpose and cluster bombs, missiles, rockets, and storage pods. It also has four internal bomb bay stations that can be used to carry general purpose bombs, [Vous devez être inscrit et connecté pour voir ce lien], and special stores (B57 and B61 nuclear weapons).

Fifty-nine [Vous devez être inscrit et connecté pour voir ce lien] chutes are fitted, as well as a dedicated Search and Rescue (SAR) chute.

The S-3 is fitted with the ALE-39 countermeasure system and can carry up to 90 rounds of [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien], and expendable jammers (or a combination of all) in three dispensers.

A retractable [Vous devez être inscrit et connecté pour voir ce lien] (MAD) Boom is fitted in the tail.

In the late 1990s, the S-3B's role was changed from anti-submarine warfare (ASW) to anti-surface warfare (ASuW).

At that time, the MAD Boom was removed, along with several hundred pounds of submarine detection electronics.

With no remaining sonobuoy processing capability, most of the sonobuoy chutes were faired over with a blanking plate.

Operational history


On 20 February 1974, the S-3A officially became operational with the Air Antisubmarine Squadron FORTY-ONE (VS-41), the "Shamrocks," at [Vous devez être inscrit et connecté pour voir ce lien], California, which served as the initial S-3 Fleet Replacement Squadron (FRS) for both the Atlantic and Pacific Fleets until a separate Atlantic Fleet FRS, VS-27, was established in the 1980s.

The first operational cruise of the S-3A took place in 1975 with the VS-21 "Fighting Redtails" aboard [Vous devez être inscrit et connecté pour voir ce lien].

Starting in 1987, some S-3As were upgraded to S-3B standard with the addition of a number of new sensors, avionics, and weapons systems, including the capability to launch the [Vous devez être inscrit et connecté pour voir ce lien].

The S-3B could also be fitted with "[Vous devez être inscrit et connecté pour voir ce lien]" external fuel tanks that allowed the Viking to refuel other aircraft.

In July 1988, VS-30 became the first fleet squadron to receive the enhanced capability Harpoon/ISAR equipped S-3B, based at NAS Cecil Field in Jacksonville, FL. 16 S-3As were converted to ES-3A Shadows for carrier-based [Vous devez être inscrit et connecté pour voir ce lien] (ELINT) duties.

Six aircraft, designated US-3A, were converted for a specialized utility and limited cargo [Vous devez être inscrit et connecté pour voir ce lien] requirement.

Plans were also made to develop the KS-3A carrier-based [Vous devez être inscrit et connecté pour voir ce lien] aircraft to replace the retired [Vous devez être inscrit et connecté pour voir ce lien], but this program was ultimately cancelled after the conversion of just one early development S-3A.