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Sabtu, 18 Januari 2014

Al Gore says use of geo-engineering to head off climate disaster is insane

Belief in an instant planet-wide quick-fix, such as blocking sunlight with sulphur, is delusional, US activist declares
Nasa image of Arctic sea ice
A Nasa image of declining Arctic sea ice in 2005 (compared with 1979 shown by the yellow line). Photograph: Ho/AFP/Getty Images
Al Gore said on Wednesday it would be "insane, utterly mad and delusional in the extreme" to turn to geo-engineering projects to avoid a climate catastrophe.
The UN climate panel, in the next edition of its blockbuster reports, will warn that governments might have to extract vast amounts of greenhouses gases from the air by 2100 to limit climate change, according to a draft copy of the report seen by Reuters.
But the former vice president of the US said that searches for an instant solution, which he said were born of desperation, were misguided and could lead to an even bigger catastrophe.
"The idea that we can put a different form of pollution into the atmosphere to cancel out the effects of global warming pollution is utterly insane," he told a conference call for South African reporters.
He added: "The fact that some scientists who should know better are actually engaged in serious discussion of those alternatives is a mark of how desperate some of them are feeling due to the paralysis in the global political system."
In March Gore will expand his climate leadership training programmes to South Africa. He said he believed those leadership training sessions (this is his 24th) had developed a cadre of leaders who were helping to find political solutions for climate change.
The draft climate report of the Intergovernmental Panel on Climate Change, due for release in Germany in April, said governments might have to turn increasingly to technologies for "carbon dioxide removal" to keep warming below the dangerous threshold of 2 degrees.
The draft said those technologies might involve capturing and burying emissions from coal-fired power plants, or planting more forests. But there has been debate in the environmental community over other more radical solutions.
On geo-engineering Gore drew a distinction between small-scale interventions, such as white roofs, and large-scale projects meant to extract or neutralise emissions from the air or block the sunlight. Those ideas, he said, carried enormous risks.
"The most discussed so-called geo-engineering proposals – like putting sulphur dioxide in the atmosphere to reflect incoming sunlight – that's just insane. Let's just describe that clearly – it is utterly mad," Gore told the conference call.
He warned that such large and untested experiments carried enormous risks while "doing nothing to address other consequences of climate change such as ocean acidification".
He said: "We are already engaged in a planet-wide experiment with consequences we can already tell are unpleasant for the future of humanity. So the hubris involved in thinking we can come up with a second planet-wide experiment that would exactly counteract the first experiment is delusional in the extreme."
Gore was also cool on the other quick-fix of nuclear power, advocated by some. Late last year four leading US scientists, including the climatologist James Hansen, wrote an open letter urging environmentalists to rethink their opposition to nuclear power.
Gore's re-thinking has apparently gone in the other direction. He told the call he had been an enthusiastic supporter of nuclear energy when he was in Congress. He was not opposed to nuclear energy now, he said. But he said the current state of technology in the nuclear energy industry did not yet warrant a big expansion.
"I do believe that it may be possible for scientists and researchers to develop a better and more inherently safer and cheaper form of nuclear reactor, which may yet play a significant role in resolving this crisis," he told the call. But he added: "It is not available now."
He said he thought such nuclear developments were still 10 or 15 years away. "Unless there are breakthroughs I think the role of nuclear power is likely to be limited to near the level of contribution it is now," he said.

Jumat, 17 Januari 2014

Douglas A-3 Skywarrior

From Wikipedia, the free encyclopedia
  
A-3 (A3D) Skywarrior
RoleStrategic bomber
ManufacturerDouglas Aircraft Company
DesignerEd Heinemann
First flight28 October 1952
Introduction1956
Retired27 September 1991
StatusPhased out of service
Primary userUnited States Navy
Produced1956–1961
Number built282
Developed intoDouglas B-66 Destroyer
The Douglas A-3 Skywarrior was designed as a strategic bomber for the United States Navy and was among the longest serving carrier-based aircraft in history. It entered service in the mid-1950s and was retired in 1991. Throughout its service, it was the heaviest operational aircraft to operate from aircraft carriers,[1] earning its nickname, "The Whale".[2] Its primary function for much of its later service life was as an electronic warfare platform, tactical air reconnaissance platform, and high capacity aerial refueling tanker.[3]
A modified derivative also served in the U.S. Air Force until the early 1970s as the B-66 Destroyer, serving as a tactical bomber, electronic warfare aircraft (EB-66C) and RB-66 reconnaissance bomber. The Skywarrior is one of only two U.S. Navy attack aircraft intended as a strategic bomber to enter full-scale service (the other being its predecessor, the North American AJ Savage). The Martin P6M SeaMaster tested well, even though the prototype crashed, but never entered service due to the Navy fearing loss of funding for surface ships and submarines. The pending elimination of the flying boat platform from the U.S Navy also entered into the decision regarding the P6M. The carrier-based supersonic North American A-5 Vigilante was also originally designed for strategic nuclear strike missions and initially, very briefly, supplanted the A-3 in that role beginning in the early 1960s. However, with the removal of aircraft carriers from the Single Integrated Operational Plan (SIOP), the realization that very high altitude penetration of the Soviet Union was no longer feasible (which also caused the cancellation of the North American B-70 Valkyrie program) and the transfer of the U.S. Navy's strategic nuclear deterrence mission to the Fleet Ballistic Missile submarine force, the Vigilante saw its mission changed to carrier-based tactical air reconnaissance.

Development

A3D-1 at NAS Jacksonville, Florida in the 1950s
Early in World War II, the U.S. Navy began to explore the concept of a jet-powered aircraft operating from aircraft carriers. Success encouraged further development of the concept, and early in the post war years, the U.S. Navy began to consider jet power as a possible means of operating carrier-based aircraft that were large enough to provide a strategic bombing capability.
In January 1948, the Chief of Naval Operations issued a requirement to develop a long-range, carrier-based attack plane that could deliver a 10,000 lb (4,536 kg) bomb load or a nuclear weapon.[4] The aircraft was planned to operate from the proposed United States-class "supercarriers", much larger than existing carriers, and the specification set a target loaded weight of 100,000 lb (45,500 kg). Ed Heinemann, chief designer of the Douglas Aircraft Company, later to win fame for the A-4 Skyhawk, fearing that the United States-class was vulnerable to cancellation, proposed a significantly smaller aircraft of 68,000 lb (31,000 kg) loaded weight, capable of operating from existing carriers.[5][6] The contract which the U.S. Navy awarded to the Douglas Aircraft Company on 29 September 1949 led to the development and production of the A3D Skywarrior. The prototype XA3D-1 first flew on 28 October 1952.
Considerable development problems, largely with the original engines, delayed the introduction of the Skywarrior until spring 1956. The A-3 was, by far, the largest and heaviest aircraft ever designed for routine use on an aircraft carrier, though ironically it was the smallest proposal among other proposals which could only be deployed on even larger carriers not yet in service.[4] Because of its cumbersome size, and less-than-slender profile, it was nicknamed "The Whale" (after it converted to the electronic warfare role, it became "The Electric Whale"). Production ceased in 1961.

Design

The Skywarrior had a 36° degree swept wing and two Pratt & Whitney J57 turbojet engines. Early prototypes had used the intended Westinghouse J40, a powerplant that proved to be disastrous and subsequently canceled. The turbojets could be supplemented by a provision for twelve 4,500 lbf (20 kN) thrust JATO bottles, allowing takeoff from carriers that did not have catapults. The aircraft had a largely conventional semi-monocoque fuselage, with the engines in underwing nacelles. Flight controls were hydraulic, and for storage below deck, the A-3's wings folded outboard of the engines, lying almost flat, and its vertical stabilizer was hinged to starboard.[4] Capacious internal fuel tanks provided long range.
Camera arrangement of a camouflaged RA-3B of Heavy Photographic Squadron 61.
The early A-3 variants had a crew of three: pilot, bombardier/navigator (BN) and crewman/navigator (aka: third crewman). An unusual cockpit configuration was incorporated with the three crew sitting under a framed canopy. In the raised compartment, the pilot and bombardier/navigator sat in a side-by-side arrangement with the pilot's station on port side having full flight controls. On initial variants, a third crew member, who also acted as a gunner for the twin tail-mounted 20mm cannons that briefly equipped the original bomber version of the A3D/A-3A ( removed and replaced by ECM equipment), sat behind the pilot in an aft-facing seat. The third crewman station had the sextant for celestial navigation and the defensive electronic counter measures equipment. Later electronic reconnaissance variants could accommodate a crew of seven with flight crew consisting of a pilot, co-pilot and navigator plus four electronic systems operators occupying stations in the former bomb bay in the spacious fuselage.[4]
Efforts to reduce weight had led to the deletion of ejection seats during the design process for the Skywarrior, based on the assumption that most flights would be at high altitude. A similar arrangement with an escape tunnel had been used on the F3D Skyknight.[7]Aircrews began joking morbidly that "A3D" stood for "All Three Dead."[8] (In 1973, the widow of a Skywarrior crewman killed over Vietnam sued the McDonnell Douglas Aircraft Company for not providing ejection seats in the A-3.[7]) In contrast, the US Air Force's B-66 Destroyer was equipped with ejection seats throughout its service life.
Documented history of mechanical failures in the A3D / A-3 showed a rate well above average. While there were magazine articles that conjectured that the safety problem was compounded by assigning weaker pilots to slower jets like the A-3, during their heyday, Skywarrior pilots were often "best-of-the-best" and were, with few exceptions, senior pilots with a minimum of 1500 hours jet time,due to its critical nuclear strike mission role and the difficulty of bringing such a large plane aboard, especially at night on the smaller carriers. Originally, the A3 bombers were assigned to all the attack carriers which included the WWII CVA-27 class and the just postwar CVA41 class. [9]
The Skywarrior could carry up to 12,000 lb (5,443 kg) of weaponry in the fuselage bomb bay, which in later versions was used for sensor and camera equipment or additional fuel tanks. An AN/ASB-1A bomb-director system was initially installed, later replaced by a revised AN/ASB-7 with a slightly reshaped nose. Defensive armament was two 20mmcannons in a radar-operated tail turret designed by Westinghouse, soon removed in favor of electronic counter measure equipment. Although some bombing missions would be carried out early in the Vietnam war, most bombing would be carried out by more nimble attack and fighter bombers, and the Skywarrior would serve mostly as a tanker and electronic warfare support aircraft.

Operational history

Nuclear bomber

An A3D-2 from VAH-9 suffers a nose wheel collapse while landing onUSS Saratoga (CVA-60), c. 1959.
Prior to the initial operational capability of the U.S. Navy's Polaris-armed Fleet Ballistic Missile submarines, the A-3 was the Navy's critical element in the U.S. nuclear deterrent. Squadrons were established in two Heavy Attack Wings (HATWINGs), with one wing established at NAS Whidbey Island, Washington while the other wing was initially established at NAS Jacksonville, Florida before relocating to NAS Sanford, Florida. The wing at NAS Whidbey Island would later transition to the EKA-3B variant, eventually forming the nucleus for the Navy's Grumman EA-6B Prowler community, while the wing at NAS Sanford would convert to the A3J Vigilante in the nuclear heavy attack mission, followed by conversion to the RA-5C and transition to the reconnaissance attack mission. The Vigilante wing would also continue to retain a small number of TA-3B aircraft for training Naval Flight Officers in the Vigilante's radar and navigation systems. The Skywarrior's strategic bombing role faded after 1964, briefly being complemented by the A3J Vigilante, (later redesignated as the A-5A Vigilante) . Soon afterward, the Navy abandoned the concept of carrier-based strategic nuclear weaponry for the successful Polaris missile-equipped Fleet Ballistic Missile submarine program and all A-5As were converted to the RA-5C Vigilante reconnaissance variant. Many A3B's were converted to a combination tanker-ECM aircraft.

Vietnam

VAH-4 A-3B from USS Oriskanydropping a Mk 83 bomb, 1965.
A black RA-3B from VAP-61 aboard USSConstellation, 1967.
Skywarriors saw some use in the conventional bombing and mine-laying role (A-3B) during the Vietnam War from 1964 through 1967, often to deliver the 2000 lbs bombs. The A-3 found subsequent service in the tanker (KA-3B, EKA-3B), photographic reconnaissance(RA-3B), electronic reconnaissance (EA-3B), and electronic warfare (EKA-3B) roles. Equipped with a drogue refueling hose and basket that was compatible with the "probe and drogue" refueling systems of all U.S. Navy, U.S. Marine Corps and some U.S. Air Force tactical jets, the Skywarrior would not only extend the range of a strike force, but save returning pilots short on fuel, much like the larger and more well known Air Force Boeing KC-135 Stratotanker.
For most of the Vietnam War, EA-3Bs of Fleet Air Reconnaissance Squadron 1 (VQ-1) flew from Da Nang Air Base in South Vietnam, providing continuous electronic reconnaissance capability over the area, including the so-called Ho Chi Minh trail and all the way north to Haiphong harbor. This was known as VQ-1 "Det.B". The aircrew and ground support personnel were TAD from their home base at NAS Atsugi, Japan and after 1970, NAS Agana, Guam. After Det B was disestablished, VQ-1 provided detachments of two EA-3B aircraft that deployed with Western Pacific and Indian Ocean (WESTPAC/IO) bound aircraft carrier battle groups up until the late 1980s when it was replaced by the Lockheed ES-3A Shadow.
In addition, a version of the A-3B was modified into the RA-3B and used in Vietnam as a photo reconnaissance aircraft. Heavy Photographic Squadron 61 (VAP-61) at NAS Agana, Guam and sister squadron VAP-62 at NAS Jacksonville, Florida furnished crews and flew out of Da Nang AB performing mapping and intelligence gathering flight over the Southeast Asia area. With 12 camera stations the RA-3B was well equipped to perform cartographic mapping of areas where no detail maps existed. With IR gear installed, the RA-3B was used at night to monitor the movement of troops down roads and trails in Laos. Other locations included Det Tango at Don Muang Royal Thai Air Force Base in Bangkok, Thailand, Det Southpaw at RAAF Base Townsville, Australia, as well as work out of Osan Air Base, South Korea.

Tanker role

An EKA-3B from VAQ-135 refueling anVF-211 F-8J off Vietnam, 1972.
During Vietnam, the Skywarrior was modified into a multimission tanker variant, the EKA-3B, that was a real workhorse for the carrier air wing. A-3 attack aircraft were modified to KA-3B tankers. Electronic jamming equipment was added without removing tanker capability so the EKA-3B could jam enemy radar while waiting to refuel tactical aircraft.[10] Buddy tanking using A-4 Skyhawks and A-7 Corsair IIs, and inflight refueling using A-3 Skywarriors was utilized by the U.S. Navy in the Vietnam theater of operations from at least 1966 through 1973.[citation needed] Eventually, the EKA-3B was replaced by the smaller dedicated Grumman KA-6D Intruder tanker, which although it had less capacity and endurance, was deployed in greater numbers within the carrier's air wing. Two additional Naval Reserve units were established in the early 1970s as air refueling squadrons, VAK-208 and VAK-308, at NAS Alameda, California. Both units operated aircraft with electronic warfare equipment removed and were redesignated as KA-3Bs. VAK-208 and VAK-308 were decommissioned in the early 1990s.

Cold War

An EA-3B of Fleet Air Reconnaissance Squadron Two (VQ-2) lands on theUSS Kitty Hawk in 1987
The EA-3 variant was an indispensable resource for the Fleet Commander and was used in critical electronic intelligence (ELINT) roles operating from aircraft carrier decks and ashore supplementing the larger Lockheed EP-3. Its last service was as an ELINT platform during Desert Storm.

Reconnaissance

The EA-3B variant was modified for electronic intelligence against the Warsaw Pact. Missions were flown around the globe beginning in 1956, with the U.S. Air Force EB-47 Stratojet flying a similar mission. The EA-3B carried a crew of seven, with flight crew of three in the cockpit and an Electronic Warfare Officer and three electronic systems operators/evaluators in the converted weapons bay. It offered unique electronic reconnaissance capabilities in numerous Cold War-era conflicts and the Vietnam War.[11]

Retirement

EA-3Bs survived long enough to participate in the first Gulf War in 1991, although the Skywarrior was out of Navy service by September 1991. For more than three decades, the 282 Skywarriors the U.S. Navy procured served effectively in many roles with the last USN Skywarriors retiring on 27 September 1991. U.S. Navy RDT&E units, notably Naval Air Systems Command (NAVAIR) activities at NAS Point Mugu and NAWS China Lake, attempted to retain their A-3 testbeds. This plan ultimately failed when Vice Admiral Richard Dunleavy, as Deputy Chief of Naval Operations for Air Warfare and an old A-3 bombardier/navigator himself, made the final decision to retire the type.

Post-retirement career

In an agreement Hughes Aircraft had with the U.S. Navy, at least one A-3 aircraft was retained in inviolate storage at Davis-Monthan AFB for long term support for major structural parts. Westinghouse also operated an A-3 in a similar arrangement.
The NAVAIR Weapons System Manager, who participated in the drafting of the contract, saw that support as no longer possible and Hughes was contacted to meet withWestinghouse and Raytheon to finalize plans for the support shutdown of the aircraft. At the last Integrated Logistics meeting at NAS Alameda, California, both Raytheon and Hughes indicated their willingness to obtain fleet A-3 Skywarrior assets instead of sending them to Davis-Monthan AFB, Arizona, thereby saving the airframes from destruction and saving the US Navy the cost of storage at AMARC.
As the plan matured, two other contractors, Thunderbird Aviation and CTAS also elected to participate in similar agreements. The fleet spares from ASO were distributed between the contractors evenly, and warehouses were emptied all over the US. Unfortunately, due to misunderstandings and reorganizations within the US Navy, the world-wide ASO assets were scrapped, not getting to the contractors. In early 1993, CTAS decided that they no longer had use for their aircraft, and Hughes had several programs needing additional assets.
NRA-3B of the Pacific Missile Test Center in 1982
In early 1994, a US Air Force program decided to modify an A-3 for F-15 radar tests, and the only available airframe was stored at NAS Alameda since the fleet shutdown. Hughes added that aircraft to the bailment, and ferried the aircraft to Van Nuys for modifications. An entire nose section was removed from a stricken F-15B at AMARC at Davis-Monthan AFB, Arizona and grafted onto the front of the aircraft. Racks and equipment were installed in the cabin, and the aircraft was utilized by Hughes and the USAF for F-15 software development.
In 1994, Westinghouse decided to terminate their agreement with the Navy, and Thunderbird added their aircraft to the Thunderbird bailment. In 1996, Thunderbird Aviation went into receivership, and Hughes, through mutual cost savings to the government, added the Thunderbird assets to the contract, prepping them for ferry at Deer Valley airport, and relocating them to Mojave, California and Tucson, Arizona for long-term storage.
In December 1996, Raytheon bought the aerospace units of Hughes Aircraft Company. Hughes Aeronautical Operations, now a part of Raytheon Systems, continued to operate the A-3s from their base at Van Nuys Airport, California.[12] These aircraft have participated at several military air shows, telling visitors that the plane continued to be valuable for its load capacity compared to corporate jets, and its performance compared to small airliners.
On 30 June 2011, the last flyable EA-3D (N875RS) a Raytheon aircraft, arrived at NAS Pensacola, Florida for retirement and display at the National Naval Aviation Museum.

Variants

An A3D-1 of Heavy Attack Squadron 3 (VAH-3) on the USS Franklin D. Rooseveltin 1957. VAH-3 became the A3D/A-3 Replacement Air Group (RAG) squadron for the Atlantic Fleet in 1958.
Note: under the original Navy designation scheme, the Skywarrior was designated A3D (third Attack aircraft from Douglas Aircraft). In September 1962, the new Tri-Services designation system was implemented and the aircraft was redesignated A-3. Where applicable, pre-1962 designations are listed first, post-1962 designations in parentheses.
  • XA3D-1: Two prototypes with Westinghouse J40 turbojets, no cannon in tail turret.
  • YA3D-1 (YA-3A): One pre-production prototype with Pratt & Whitney J57 engines. Later used for tests at the Pacific Missile Test Center.
  • A3D-1 (A-3A): 49 initial production versions, serving largely in developmental role in carrier service.
  • A3D-1P (RA-3A): One A3D-1 converted as a prototype for the A3D-2P with camera pack in the weapon bay.
  • A3D-1Q (EA-3A): Five A3D-1s converted for the electronic reconnaissance (ELINT) role, with ECM equipment and four operators in weapons bay.
  • A3D-2 (A-3B): Definitive production bomber version, with stronger airframe, more powerful engines, slightly larger wing area (812 ft²/75 m² versus 779 ft²/72 m²), provision for in-flight refueling reel for tanker role. Final 21 built had new AN/ASB-7 bombing system, reshaped nose; deleted tail turret in favor of electronic warfare installation.
  • A3D-2P (RA-3B): 30 photo-reconnaissance aircraft with weapons bay package for up to 12 cameras plus photoflash bombs. Increased pressurization allowed camera operator to enter the bay to check the cameras. Some retained tail guns, but most were later converted to ECM tail of late A-3Bs.
  • A3D-2Q (EA-3B): 24 electronic warfare versions with pressurized compartment in former weapon bay for one Electronic Warfare Officer and three ESM operators, various sensors. This was the longest serving version of the "Whale" and the most widely known throughout the fleet. Some early models had tail guns, but these were replaced with the ECM tail. The EA-3B was assigned to fleet reconnaissance squadrons VQ-1 (Japan and later Guam) and VQ-2 (Rota. Spain) where they flew alongside the Lockheed EC-121 Warning Star and the EP-3B and EP-3E. It served in the fleet for almost 40 years, and was replaced by the ES-3A Shadow flown by two Fleet Air Reconnaissance (VQ) squadrons: VQ-5 at NAS North Island, California and VQ-6 at NAS Cecil Field, Florida. They were decommissioned less than 10 years after their commissioning due to budget constraints.
  • A3D-2T (TA-3B): 12 bomber-trainer versions. Five later converted as VIP transports (two redesignated UTA-3B).
  • KA-3B: 85 A-3B bombers refitted in 1967 for the tanker role with probe-and-drogue system in place of bombing equipment.
  • EKA-3B: 34 KA-3B tankers refitted for dual Electronic countermeasures (ECM)/tanker role, with electronic warfare equipment and tail fairing in place of rear turret. Most were converted back to KA-3B configuration (with no ECM gear) after 1975.
A VA-3B used by the Chief of Naval Operations at Nellis AFB.
  • ERA-3B: Eight RA-3Bs converted as electronic aggressor aircraft (primarily for war-at sea exercises) with ECM in new extended tail cone, ventral "canoe" fairing, cylindrical fairing atop vertical fin, and two detachable ram-air turbine powered ALQ-76 countermeasures pods (one under each wing). Added chaff (radar countermeasure) dispensers (streaming chaff from the tail cone and two self-protection chaff dispensers on the aft fuselage) and four ram-air turbines (two per side) to power the equipment located in the former bomb bay. Crew increased to four: pilot, navigator, crew chief, and Electronic Countermeasures Officer (ECMO) with one generally unused "jumpseat" in the aft crew compartment (formerly the weapon bay). There was no equipment position for a second Electronic Countermeasures Officer or enlisted crewman in the converted weapon bay. The "jump seat" was used for qualified instructor ECMOs training new ECMOs, for guest observers on operational flights, or for passengers during operational deployment transits. While the ERA-3B could withstand the stresses of a cable arrested landing, the ALT-40 and ALR-75 equipment in the former bomb bay was not stressed to withstand a catapult launch and the ERA-3B was never deployed aboard carriers. The ERA-3B served with VAQ-33 and later with VAQ-34.
  • NRA-3B: Six RA-3Bs converted for various non-combat test purposes.
  • VA-3B: Two EA-3B converted as VIP transports. Both aircraft were assigned to the Chief of Naval Operations flying from Andrews AFB in Washington, DC.[citation needed]
  • NTA-3B: One aircraft converted by Hughes/Raytheon used to test radar for the F-14D Tomcat.

B-66 Destroyer

The U.S. Air Force ordered 294 examples of the derivative B-66 Destroyer, most of which were used in the reconnaissance and electronic warfare roles. The Destroyer was fitted with ejection seats.

Operators

An A3D-2 of Heavy Attack Squadron 6 (VAH-6) lands on the USS Ranger in 1958
 United States

Specifications (A3D-2/A-3B Skywarrior)

Douglas A-3B Skywarrior 3-view drawing.png
Data from McDonnell Douglas Aircraft since 1920[30]
General characteristics
Performance
Armament
  • Guns: 2 20 mm M3L cannon in the tail turret[32]
  • Bombs: 12,800 pounds (5,800 kg) of free-fall bombs or mines,[32] including any combination of[8]