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Ronald J. Clarke

2009-06-25T17:12:16Z

Part Time Security: Corrected a mistake and enlarged picture

{{otherpeople2|Ronald Clarke}}

[[File:Ronald Clarke.jpg|thumb|right|300px|Ronald Clarke in 2009]]

'''Ronald J. Clarke''' is an [[Paleoanthropology|paleoanthropologist]] most notable for the discovery of "[[Little Foot]]", an extraordinary complete skeleton of [[Australopithecus]], in the [[Sterkfontein]] Caves. <ref>"Ancient ancestor reveals skeletal stamina" by B. Bower ''Science News'' December 26, 1998. [http://www.sciencenews.org/pages/pdfs/data/1998/154-25/15425-04.pdf full text]</ref>. A more technical description of various aspects of his description of the ''Australopithecus'' skeleon was published in the ''Journal of [[Quaternary]] Science,'' <ref>"The new hominid skeleton from Sterkfontein, South Africa: age and preliminary assessment" ''Journal of [[Quaternary]] Science,'' vol. 14, Issue 4, pp.293-298''
[http://doi.wiley.com/10.1002/(SICI)1099-1417(199907)14:4%3C293::AID-JQS471%3E3.0.CO;2-X abstract] and [http://adsabs.harvard.edu/abs/1999JQS....14..293P*] </ref>

He also discovered the [[Homo ergaster]] partial cranium SK 847.<ref name="sk847">[[Donald Johanson]] and Blake Edgar, ''From Lucy to Language'', 1996, New York:Simon & Schuster. pg. 184</ref>. He also played a role in the discovery of a new skeleton of [[Homo habilis]] related to [[Homo rudolphensus]] <ref>"Late Pliocene Homo and Hominid Land Use from Western Olduvai Gorge, Tanzania." ''Science'' Vol. 299. no. 5610, pp. 1217 - 1221 [http://www.sciencemag.org/cgi/content/abstract/299/5610/1217 abstract] </ref>

He was associated with the [[University of the Witwatersrand]] until he was fired by [[Lee R. Berger|Lee Berger]], the head of the university's Palaeoanthropology Research Unit. He was then hired by [[Johann Wolfgang Goethe University of Frankfurt am Main]] in [[Frankfurt, Germany]] and allowed to continue his work excavating "Little Foot."<ref name="job">"World-renowned Scientist sacked" http://www.geotoursafrica.com/english/news.htm (scroll down) Accessed 15 May 2006</ref>

==References==
{{reflist}}

==See also==
* [[List of fossil sites]] ''(with link directory)''
* [[List of hominina fossils|List of hominina (hominid) fossils]] ''(with images)''

==External links==
*[http://www.talkorigins.org/faqs/homs/littlefoot.html Little Foot [[TalkOrigins Archive]]]
*[http://www.washingtonpost.com/wp-srv/national/daily/dec98/safrica10.htm Full Australopithecus Fossil Found in South Africa] (''Washington Post'')

{{anthropologist-stub}}

{{DEFAULTSORT:Clarke, Ronald J.}}

Ronald J. Clarke

2009-06-25T17:11:48Z

Part Time Security: Added a picture to the article

{{otherpeople2|Ronald Clarke}}

[[File:Ronald Clarke.jpg|thumb|right|200px|]Ronald Clarke in 2009]]

'''Ronald J. Clarke''' is an [[Paleoanthropology|paleoanthropologist]] most notable for the discovery of "[[Little Foot]]", an extraordinary complete skeleton of [[Australopithecus]], in the [[Sterkfontein]] Caves. <ref>"Ancient ancestor reveals skeletal stamina" by B. Bower ''Science News'' December 26, 1998. [http://www.sciencenews.org/pages/pdfs/data/1998/154-25/15425-04.pdf full text]</ref>. A more technical description of various aspects of his description of the ''Australopithecus'' skeleon was published in the ''Journal of [[Quaternary]] Science,'' <ref>"The new hominid skeleton from Sterkfontein, South Africa: age and preliminary assessment" ''Journal of [[Quaternary]] Science,'' vol. 14, Issue 4, pp.293-298''
[http://doi.wiley.com/10.1002/(SICI)1099-1417(199907)14:4%3C293::AID-JQS471%3E3.0.CO;2-X abstract] and [http://adsabs.harvard.edu/abs/1999JQS....14..293P*] </ref>

He also discovered the [[Homo ergaster]] partial cranium SK 847.<ref name="sk847">[[Donald Johanson]] and Blake Edgar, ''From Lucy to Language'', 1996, New York:Simon & Schuster. pg. 184</ref>. He also played a role in the discovery of a new skeleton of [[Homo habilis]] related to [[Homo rudolphensus]] <ref>"Late Pliocene Homo and Hominid Land Use from Western Olduvai Gorge, Tanzania." ''Science'' Vol. 299. no. 5610, pp. 1217 - 1221 [http://www.sciencemag.org/cgi/content/abstract/299/5610/1217 abstract] </ref>

He was associated with the [[University of the Witwatersrand]] until he was fired by [[Lee R. Berger|Lee Berger]], the head of the university's Palaeoanthropology Research Unit. He was then hired by [[Johann Wolfgang Goethe University of Frankfurt am Main]] in [[Frankfurt, Germany]] and allowed to continue his work excavating "Little Foot."<ref name="job">"World-renowned Scientist sacked" http://www.geotoursafrica.com/english/news.htm (scroll down) Accessed 15 May 2006</ref>

==References==
{{reflist}}

==See also==
* [[List of fossil sites]] ''(with link directory)''
* [[List of hominina fossils|List of hominina (hominid) fossils]] ''(with images)''

==External links==
*[http://www.talkorigins.org/faqs/homs/littlefoot.html Little Foot [[TalkOrigins Archive]]]
*[http://www.washingtonpost.com/wp-srv/national/daily/dec98/safrica10.htm Full Australopithecus Fossil Found in South Africa] (''Washington Post'')

{{anthropologist-stub}}

{{DEFAULTSORT:Clarke, Ronald J.}}

Ronald J. Clarke

2009-06-25T17:11:41Z

Part Time Security: Added a picture to the article

{{otherpeople2|Ronald Clarke}}

[[File:Ronald Clarke.jpg|thumb|right|200px|]Ronald Clarke in 2009]

'''Ronald J. Clarke''' is an [[Paleoanthropology|paleoanthropologist]] most notable for the discovery of "[[Little Foot]]", an extraordinary complete skeleton of [[Australopithecus]], in the [[Sterkfontein]] Caves. <ref>"Ancient ancestor reveals skeletal stamina" by B. Bower ''Science News'' December 26, 1998. [http://www.sciencenews.org/pages/pdfs/data/1998/154-25/15425-04.pdf full text]</ref>. A more technical description of various aspects of his description of the ''Australopithecus'' skeleon was published in the ''Journal of [[Quaternary]] Science,'' <ref>"The new hominid skeleton from Sterkfontein, South Africa: age and preliminary assessment" ''Journal of [[Quaternary]] Science,'' vol. 14, Issue 4, pp.293-298''
[http://doi.wiley.com/10.1002/(SICI)1099-1417(199907)14:4%3C293::AID-JQS471%3E3.0.CO;2-X abstract] and [http://adsabs.harvard.edu/abs/1999JQS....14..293P*] </ref>

He also discovered the [[Homo ergaster]] partial cranium SK 847.<ref name="sk847">[[Donald Johanson]] and Blake Edgar, ''From Lucy to Language'', 1996, New York:Simon & Schuster. pg. 184</ref>. He also played a role in the discovery of a new skeleton of [[Homo habilis]] related to [[Homo rudolphensus]] <ref>"Late Pliocene Homo and Hominid Land Use from Western Olduvai Gorge, Tanzania." ''Science'' Vol. 299. no. 5610, pp. 1217 - 1221 [http://www.sciencemag.org/cgi/content/abstract/299/5610/1217 abstract] </ref>

He was associated with the [[University of the Witwatersrand]] until he was fired by [[Lee R. Berger|Lee Berger]], the head of the university's Palaeoanthropology Research Unit. He was then hired by [[Johann Wolfgang Goethe University of Frankfurt am Main]] in [[Frankfurt, Germany]] and allowed to continue his work excavating "Little Foot."<ref name="job">"World-renowned Scientist sacked" http://www.geotoursafrica.com/english/news.htm (scroll down) Accessed 15 May 2006</ref>

==References==
{{reflist}}

==See also==
* [[List of fossil sites]] ''(with link directory)''
* [[List of hominina fossils|List of hominina (hominid) fossils]] ''(with images)''

==External links==
*[http://www.talkorigins.org/faqs/homs/littlefoot.html Little Foot [[TalkOrigins Archive]]]
*[http://www.washingtonpost.com/wp-srv/national/daily/dec98/safrica10.htm Full Australopithecus Fossil Found in South Africa] (''Washington Post'')

{{anthropologist-stub}}

{{DEFAULTSORT:Clarke, Ronald J.}}

Kampfhubschrauber

2009-05-16T16:43:23Z

Part Time Security:

{{Refimprove|article|date=October 2006}}
[[Image:AH-64 Apache 060224.jpg|thumb|right|An [[AH-64 Apache]] helicopter of the [[U.S Army]]]]

An '''attack helicopter''' is a [[military helicopter]] specifically designed and built to carry weapons for attacking targets on the ground, such as enemy infantry, armored vehicles and structures. Weapons used on attack helicopters can include [[autocannon]]s, [[machine-gun]]s, [[rocket]]s, and guided [[missile]]s such as the [[AGM-114 Hellfire|Hellfire]]. Many attack helicopters are also capable of carrying [[air to air missile]]s, though mostly for purposes of self-defense. Today's attack helicopter has two main roles: first, to provide direct and accurate [[close air support]] for ground troops, and the second, in the [[Anti tank#Helicopters|anti tank]] role to destroy enemy armor concentrations. Attack helicopters are also used to supplement lighter helicopters in the armed scout role.

==History==
[[Image:Bell 209.jpg|thumb|right|Prototype of the AH-1, the first dedicated attack helicopter, and canonical example to this day.]]
[[Image:Ah56a-lc1 b.jpg|thumb|right|Cheyenne prototype]]
[[Image:Denel Rooivalk flying 2006.jpg|right|thumb|A [[South African National Defence Force|South African]] [[Denel AH-2 Rooivalk]] at [[AFB Ysterplaat|Ysterplaat]] air show in 2006]]
[[Image:Bell AH-1 Cobra.jpg|thumb|right|Current Huey-Cobra]]
[[Image:Mi-24 Desert Rescue.jpg|right|thumb|A Russian Mil Mi-24 attack helicopter.]]

In the mid-1960s the U.S. Army concluded that a purpose-built attack helicopter with more speed and firepower than current [[armed helicopter]]s was required in the face of increasingly intense ground fire (often using heavy machine guns and anti-tank rockets) from Viet Cong and NVA troops. Based on this realization, and with the growing involvement in Vietnam, the U.S. Army developed the requirements for a dedicated attack helicopter, the Advanced Aerial Fire Support System (AAFSS). The aircraft design selected for this program in 1965, was [[Lockheed Corporation|Lockheed's]] [[AH-56 Cheyenne]].<ref name="Attack-1">{{cite paper|author=Office of the Assistant Vice Chief of Staff of the Army|title=An Abridged History of the Army Attack Helicopter Program|publisher=Department of the Army|year=1973|url=http://www.webcitation.org/5JNGWqTeh}}</ref>

As the Army began its acquisition of a dedicated attack helicopter, it sought options to improve performance over the continued use of improvised interim aircraft (such as the UH-1B/C). In late 1965, a panel of high-level officers was selected to evaluate several prototype versions of armed and attack helicotpers to determine which provided the most significant increase in capability to the UH-1B. The three aircraft ranked highest during the evaluation; the Sikorsky S-61, [[H-2 Tomahawk|Kaman H-2 Tomahawk]], and Bell Huey Cobra, were selected to compete in flight trials conducted by the Army's Aviation Test Activity. Upon completion of the flight evaluations, the Test Activity recommended Bell's Huey Cobra to be an interim armed helicopter until the Cheyenne was fielded. On 13 April 1966, the U.S. Army awarded Bell Helicopter Company a production contract for 110 [[AH-1 Cobra|AH-1G Cobras]].<ref name="Attack-1" /> The Cobra had a slender fuselage to make the aircraft a smaller target, increased armor protection, and greater speed.

In 1967, the first AH-1Gs were deployed to Vietnam, around the same time that the Cheyenne successfully completed its first flight and initial flight evaluations. And while the Cheyenne program suffered setbacks over the next few years due to technical problems, the Cobra was establishing itself as an effective aerial weapons platform, despite its performance shortcomings compared to the AH-56,<ref name="Attack-1" /> and design issues of its own. By 1972, when the Cheyenne program was eventually cancelled to make way for the Advanced Attack Helicopter (AAH)<ref name="Attack-1" />, the ''interim'' "Snake" had built a solid reputation as an attack helicopter.

After Vietnam, and especially into the 1990s, the missile-armed attack helicopter evolved into a primary anti-tank weapon. Able to quickly move about the battlefield and launch fleeting "pop-up attacks", helicopters presented a major threat even with the presence of organic air defenses. The gunship became a major tool for both the US Army and their Warsaw Pact counterparts in tank warfare, and most attack helicopters became more and more optimized for the antitank mission..<ref name="Mazarella 1994">Mazarella, Mark N. [http://cgsc.cdmhost.com/cgi-bin/showfile.exe?CISOROOT=/p4013coll2&CISOPTR=1135&filename=1136.pdf#search=%222007%22 "Adequacy of U.S. Army Attack Helicopter Doctrine to Support the Scope of Attack Helicopter Operations in a Multi-Polar World"]. Fort Leavenworth, Kansas: U.S. Army Command and General Staff College, 1994. Accessed on 12 December 2007.</ref> The US Marine Corps continued to see the helicopter, as well as its fixed-wing aviation assets, in the close support role, although the Marines did dedicate a close-support helicopter in the form of the [[AH-1 Cobra]] and [[AH-1 Super Cobra]]. Soviet helicopters retained troop transport capability rather than being attack-only.

While helicopters were effective tank-killers in the Middle East, attack helicopters are being seen more in a multipurpose role. Tactics, such as [[tank plinking]], showed that fixed-wing aircraft could be effective against tanks, but helicopters retained a unique low-altitude, low-speed capability for close air support. Other purpose-built helicopters were developed for [[special operations]] missions, including the [[MH-6]] for extremely close support.

The "deep attack" role of independently operating attack helicopters came into question after a failed mission, during the [[2003 Iraq war timeline#March 24, 2003|2003 Gulf War attack on the Karbala Gap]].<ref name=WT2003-04>{{Citation
| last = Scarborough
| first = Ryan
| author-link =
| title = Apache operation a lesson in defeat; Army choppers hit without air cover.
| newspaper = Washington Times
| pages = 1
| date = April 2003
| url = http://findarticles.com/p/articles/mi_hb5244/is_200304/ai_n20780844}}</ref> A second mission in the same area, four days later, but coordinated with artillery and fixed-wing aircraft,<ref name=CRS2003-06-04>{{citation
|page = CRS-36
|url = https://www.maxwell.af.mil/au/awc/awcgate/crs/rl31946.pdf
|format=PDF|title = Iraq War: Defense Program Implications for Congress
|author = Ryan O'Rourke
|date = June 4, 2003
|publisher = Congressional Research Service
|accessdate = 2007-12-12
}}</ref> was far more successful with minimal losses.

==Modern attack helicopter==
[[Image:FZ-207 rocket launcher P1220931.jpg|left|thumb|A 19-rocket launcher.]]
[[Image:Eurocopter Tiger 2.jpg|thumb|Modern [[Eurocopter Tiger|Tiger UHT]] of the [[German Army]]]]
[[File:Westland apache wah-64d longbow zj206 arp.jpg|thumb|right|[[British Army]] [[Westland WAH-64 Apache|Westland WAH-64 Apache Longbow]]]]

During the late 1970s the [[United States Army|U.S. Army]] saw the need of more sophistication within the attack helicopter corps, allowing them to operate in all weather conditions.<ref>[http://www.realmilitaryflix.com/public/493.cfm?sd=71 ADVANCED ATTACK HELICOPTER OPERATIONS IN ADVERSE ENVIRONMENTS] - Official US Army video at Real Military Flix</ref> With that the Advanced Attack Helicopter program was started.<ref>[http://www.globalsecurity.org/military/systems/aircraft/aah.htm Advanced Attack Helicopter (AAH) (1970-1981)] - Global Security</ref> From this program the Hughes YAH-64 came out as the winner. The Soviet armed forces also saw the need of a more advanced helicopter. Military officials asked [[Kamov]] and [[Mil Moscow Helicopter Plant|Mil]] to submit designs. The [[Kamov Ka-50|Ka-50]] officially won the competition, but Mil decided to continue development of the [[Mil Mi-28|Mi-28]] that they had originally submitted.

The 1990s could be seen as the coming-of-age for the U.S. attack helicopter. The [[AH-64]] Apache was used extensively during [[Operation Desert Storm]] with great success. Apaches fired the first shots of the war, destroying enemy [[early warning radar]] and [[Surface-to-air missile|SAM]] sites with their [[Hellfire missile]]s. They were later used successfully in both of their operational roles, to direct attack against enemy armor and as aerial artillery in support of ground troops. Hellfire missile and cannon attacks by Apache helicopters destroyed many enemy tanks and armored cars.

Today, the attack helicopter has been further refined, and the AH-64D Apache Longbow demonstrates many of the advanced technologies being considered for deployment on future gunships. The Russians are currently deploying the Ka-50, and Mi-28, which are roughly equivalent though these attack aircraft are not linked into a command and control system at a level which is quite comparable to current U.S. equipment. Many students of ground attack helicopter warfare feel that linking into a network is a requirement of today's modern armies, since attack helicopters are being increasingly incorporated as part of a linked support element system by most of the armies of the world.

===Lessons learned about limitations of independent attack helicopters===
On March 24, 2003, US [[V Corps]] launched a raid, by 32 Apache helicopters, against Medina Division armor in Karbala, with an attack plan that would fly through the [[Karbala]] area. "Army officials now believe that the aviation assembly areas the Army established in the Iraqi desert had been under surveillance by enemy observers, who noticed battle preparations on the night of the 24th." The corps commander told reporters that post-strike analysis revealed that the Iraqi observers had alerted the defense using cellular telephones.<ref name=Newman2003>{{citation
|url = http://www.afa.org/magazine/oct2003/1003najaf.html
|journal = Air Force Magazine
|date = October 2003
|volume = 86
|issue = 10
|title = Ambush at Najaf: Was it just poor tactics or some deeper problem that caused the failed Apache mission?
|first = Richard J. | last = Newman
|format = {{dead link|date=May 2009}} – <sup>[http://scholar.google.co.uk/scholar?hl=en&lr=&q=author%3ANewman+intitle%3AAmbush+at+Najaf%3A+Was+it+just+poor+tactics+or+some+deeper+problem+that+caused+the+failed+Apache+mission%3F&as_publication=Air+Force+Magazine&as_ylo=&as_yhi=&btnG=Search Scholar search]</sup>
}}</ref><ref name=WT2003-04/>

As they approached, the power grid in Karbala was shut off, and the night went dark. The Apaches were taken under heavy antiaircraft fire. One was shot down (with the crew captured by Iraqi forces. They were later recovered by US forces), and enough of the others were damaged such that the raid was aborted.

Two days later, the Army again used Apaches to carry out another nighttime deep attack. Tactics used, however, were quite different than those on March 24.<ref name=CRS2003-06-04/> The damage done, "The results of the attack were respectable, if not spectacular: seven Iraqi air defense guns destroyed, along with three artillery systems, five radars, and 25 vehicles or other weapons systems. Not one Apache was shot down. Shortly afterward, the 3rd Infantry Division slashed through the Medina on its way toward Baghdad."<ref name=Newman2003/>

On March 26, other systems supported the attack, beginning with a four-minute artillery bombardment to distract the gunners. As the helicopters moved through the Najaf area, the lights again went off, and the intensity of antiaircraft fire increased as they approached the target.

Two different things were done. "The Apaches fired back on the move—rather than using the Army’s typical tactic of hovering over the battlefield. That made them harder to hit from the ground but reduced their accuracy." Also, fixed-wing fighters protected the Apaches' flanks and suppressed more air defense. As the helicopters moved in, they radioed the locations of air defense targets to the fighters.<ref name=Newman2003/>

The March 24 raid is still being analyzed, with Air Force officers suggesting that the AH-64 alone is simply not effective for deep attack without support from conventional aircraft. Other analysts think this mission was poorly planned and the Iraqis had good intelligence on their route of attack. Nevertheless, the Apache mission generally changed from deep attack to direct support of troops.

One of the most important lessons learned about the abortive raid on Iraqi tanks in [[Karbala]], Iraq, was that the AH-64 is resilient enough to function effectively even when damaged. It was also made clear, however, that attack helicopters, without coordinated [[SEAD]] (Suppression of Enemy Air Defense), cannot penetrate an alerted defense.

==Models==
Modern examples include:
* [[CAIC WZ-10]]
* [[Harbin Z-9]]
* [[AH-1 Cobra]]
** [[AH-1 SuperCobra]]
** [[AH-1Z Viper]]
* [[Mil Mi-24]]
* [[AH-64 Apache]]
** [[Westland WAH-64 Apache]]
* [[Agusta A129 Mangusta]]
* [[Eurocopter Tiger]]
* [[Mil Mi-28|Mil Mi-28 Havoc]]
* [[Kamov Ka-50]]
** [[Kamov Ka-50#Ka-52|Kamov Ka-52 Alligator]]
* [[Denel AH-2 Rooivalk]]
* [[HAL Light Combat Helicopter]]
* [[Kawasaki OH-1]]
* [[MH-6 Little Bird|AH-6 Little Bird]]
* [[RAH-66]] (canceled)

==See also==
* [[Armed helicopter]]
* [[Army aviation]]

==References==
{{Reflist}}

===Further reading===
*Duke, R.A., ''Helicopter Operations in Algeria'' [Trans. French], Dept. of the Army (1959)
*France, Operations Research Group, ''Report of the Operations Research Mission on H-21 Helicopter'' (1957)
*Leuliette, Pierre, ''St. Michael and the Dragon: Memoirs of a Paratrooper'', New York:Houghton Mifflin (1964)
*Riley, David, ''French Helicopter Operations in Algeria'' Marine Corps Gazette, February 1958, pp. 21-26.
*Shrader, Charles R. ''The First Helicopter War: Logistics and Mobility in Algeria, 1954-1962'' Westport, CT: Praeger Publishers (1999)
*Spenser, Jay P., ''Whirlybirds: A History of the U.S. Helicopter Pioneers'', Seattle, WA: University of Washington Press (1998)

{{Aviation lists}}

[[Category:Attack aircraft|Helicopter, attack]]
[[Category:Military helicopters]]

[[ar:مروحية هجومية]]
[[es:Helicóptero de ataque]]
[[fa:بالگرد جنگنده]]
[[fr:Hélicoptère d'attaque]]
[[hr:Jurišni helikopter]]
[[it:Elicottero d'attacco]]
[[he:מסוק קרב]]
[[ms:Helikopter penyerang]]
[[nl:Gevechtshelikopters]]
[[ja:攻撃ヘリコプター]]
[[no:Kamphelikopter]]
[[pt:Helicóptero de ataque]]
[[fi:Taisteluhelikopteri]]
[[sv:Attackhelikopter]]
[[vi:Trực thăng chiến đấu]]
[[zh:攻击直升机]]