View source for PIRAZ

{{Short description|Positive Identification Radar Advisory Zone}}
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{{Campaignbox United States Navy and Coast Guard patrols}}
{{Campaignbox Vietnam War}}
'''PIRAZ''' is a [[United States Navy]] [[acronym]] for '''Positive Identification Radar Advisory Zone'''.<ref name=USN>{{cite web|access-date=2008-08-16
|url=http://www.history.navy.mil/seairland/glossary.htm
|archive-url=https://web.archive.org/web/19980703151813/http://www.history.navy.mil/seairland/glossary.htm
|url-status=dead
|archive-date=3 July 1998
|title=Glossary of Abbreviations and Terms
|work=By Sea, Air and Land: An Illustrated History of the U.S. Navy and the War in Southeast Asia
|date=26 October 1997
|publisher=Naval Historical Center, United States Navy}}</ref><ref name="Lockee, April 1969, p.143">Lockee, April 1969, p.143</ref>  The zone is defined by the air search [[radar]] coverage of a ship patrolling a designated PIRAZ station.  The concept was similar to [[radar picket]] stations established in World War II.  The PIRAZ ship requires a [[Naval Tactical Data System]] radio-linked computer installation to effectively identify and track all aircraft anticipated to enter the airspace of the zone during combat.<ref name="Lockee, April 1969, p.143"/>

==History==
[[File:A-4C Skyhawks of VA-146 fly past USS Kearsarge (CVS-33) in the South China Sea on 12 August 1964 (USN 1107965).jpg|thumb|left|PIRAZ originated to protect Yankee station aircraft carriers during the Vietnam war.]]
The concept originated in the summer of 1966 as [[Yankee station]] was established for United States Task Force 77 [[aircraft carrier]]s launching strikes against [[North Vietnam]].<ref name="Cagle, May 1972, p.68">Cagle, May 1972, p.68</ref>  A fixed patrol station within range of land-based aircraft made the stationed aircraft carriers vulnerable to attack.<ref name="Lockee, April 1969, p.143"/>  A PIRAZ station was established in the westernmost portion of the [[Gulf of Tonkin]] where air search radar coverage might extend over North Vietnam and the air-strike routes from Yankee station.<ref>Smith 1998 p.180</ref>  This PIRAZ station radio call sign was "Red Crown."<ref>Futrell, et al. 1978 p.14</ref>  The first PIRAZ ships were {{USS|Chicago|CG-11|6}}, {{USS|King|DDG-41|2}}, {{USS|Mahan|DDG-42|2}}, and {{USS|Long Beach|CGN-9|2}}.<ref name="Lockee, April 1969, p.143"/>  [[Belknap class cruiser|''Belknap'' class frigates]] began rotating into PIRAZ station assignments in 1967;<ref name="Lockee, April 1969, p.144">Lockee, April 1969, p.144</ref> and {{USS|Wainwright|DLG-28|6}}, assisted in the [[Son Tay Raid]]<ref>Gargus, p.168</ref> on 21 November 1970.
[[File:USS Agerholm (DD-826) anchored off Coronado on 7 August 1976 (USN 1168655).jpg|300px|left|thumb|{{USS|Agerholm|DD-826|6}} was typical of the ships providing torpedo boat [[destroyer]] "shotgun" escort for the Gulf of Tonkin PIRAZ station.]]
PIRAZ ships carried long-range [[RIM-2 Terrier]] or [[RIM-8 Talos]] [[surface-to-air missile]]s to defend their stations.  ''Chicago'' fired RIM-8H Talos-ARM anti-radar homing missiles against North Vietnamese shore-based radar stations.<ref>Sherwood (2009) pp.31&36</ref> Each PIRAZ ship was accompanied on station by a "shotgun" [[torpedo boat]] [[destroyer]] with [[quick-firing gun]]s to defend the PIRAZ ships from torpedo boat attack.<ref>Cagle, May 1972, p.90</ref>  PIRAZ ships provided protective radar surveillance of the [[remotely piloted vehicle]]s performing aerial photo [[reconnaissance]] of North Vietnam.<ref>Parker, August 1984, pp.39&42</ref>

As the Gulf of Tonkin PIRAZ station routine developed, a PIRAZ ship would typically remain on station for approximately 30 days before being relieved by another ship.  During the 30-day relief period, the ship would usually travel to a liberty port in [[Hong Kong]] or [[Japan]] and then to the [[U.S. Naval Base Subic Bay]] in the [[Philippines]] for minor repairs and missile firing exercises before returning to the PIRAZ station.  The ship would typically return to a United States home port for approximately six months after three PIRAZ station assignments with two intervening relief periods.<ref>Odell & Purves, 1971</ref>

==Combat Information Center==
[[File:USS Chicago (CG-11) underway in the Western Pacific on 14 March 1978 (USN 1172569).jpg|300px|right|thumb|On PIRAZ duty for the May 1972, aerial mining of [[Hai Phong]] harbor, USS Chicago's air controllers guided Navy and Air Force fighter pilots to intercepts downing 12 MiG fighters while a [[RIM-8 Talos]] missile destroyed a 13th MiG fighter.<ref name="Bowman 1985 p.429">Bowman 1985 p.429</ref>]]
The PIRAZ ship [[Combat Information Center]] (or CIC) was continuously staffed by 35 to 40 officers and sailors watching radar displays, updating position and identification information for [[Naval Tactical Data System|NTDS]] computers, and maintaining radio communication with aircraft and other ships.<ref name="Lockee, April 1969, p.144"/>  Some CIC personnel acted as air traffic controllers providing either advisory control or close control.<ref name="Lockee, April 1969, p.145">Lockee, April 1969, p.145</ref>  Close (or positive) control occurred when the controller provided specific altitudes, courses, and speeds to the pilot.<ref name="Lockee, April 1969, p.145"/>  Personnel providing positive control are called Air Intercept Controllers (AIC).<ref name="Nowell, April 1986, pp.95-97">Nowell, April 1986, pp.95–97</ref>  Advisory control simply offered advice concerning proximity to operating area boundaries, nearby air traffic, or known [[Surface-to-air missile]] (SAM) or [[Anti-aircraft warfare|Anti-Aircraft Artillery]] (AAA) sites.<ref name="Lockee, April 1969, p.145"/>

''Chicago'''s CIC included a secret [[signals intelligence]] (Sigint) team using modern electronics to evaluate very weak electromagnetic radiations from North Vietnamese aircraft or SAM sites.  The team could transfer real time Sigint information to PIRAZ air controllers.<ref>Ethell & Price 1989 p.28</ref>  ''Chicago'' AICs monitored up to 50 North Vietnamese MiGs simultaneously.<ref name="Nowell, April 1986, pp.95-97"/>  On the Tonkin Gulf PIRAZ station, successful AICs concentrated on providing threat information, collecting and sorting tactical information as it developed, and informing the [[Combat Air Patrol]]s (or CAP) about the threat location and activities while letting aircrews deal with bearing drift and controlling their headings.<ref name="Nowell, April 1986, pp.95-97"/>

==Combat Air Patrol==
[[File:McDonnell F-4J Phantom II of VF-31 landing aboard USS Saratoga (CV-60) off the coast of Florida (USA), 8 January 1980 (6350715).jpg|thumb|left|A US Navy [[F-4 Phantom II|F-4J Phantom]] fighter typical of PIRAZ controlled CAP.]]
[[File:A4D-2 Skyhawk of VA-83 refuels F8U-1P Crusader of VFP-62, circa 1961 (6418322).jpg|thumb|right|[[VFA-83|VA-83]] A-4 Skyhawk refueling a [[VFP-62]] RF-8 Crusader.]]
Ships on PIRAZ station mounted the air search radar closest to enemy airfields and were best positioned to offer radar information to Navy, Air Force, and Marine Corps fighters.<ref name="Mersky & Polmar 1981 p.192">Mersky & Polmar 1981 p.192</ref>  Combat Air Patrols (CAP) were typically under advisory control, and would come under positive control when being vectored to hostile aircraft detected by the PIRAZ ship.  PIRAZ shipboard air controllers would also provide positive control for aircraft requiring in-flight refueling.<ref name="Lockee, April 1969, p.146">Lockee, April 1969, p.146</ref>  Gulf of Tonkin barrier CAP (BARCAP) routinely refueled; and CAP involved in an engagement usually returned with a low fuel state requiring emergency refueling.<ref name="Nowell, April 1986, pp.95-97"/>  Three ''Chicago'' AICs assisted 52 declared emergency refueling situations for Air Force aircraft in a single day.<ref name="Nowell, April 1986, pp.95-97"/>  Preferred procedure turns the tanker aircraft in front of the low fuel state aircraft to minimize search and maneuvering fuel consumption while allowing the fighter to continue away from hostile territory.<ref name="Nowell, April 1986, pp.95-97"/>  In some cases, damaged aircraft with leaking fuel tanks can be saved by continuous refueling from rendezvous to landing.<ref name="Nowell, April 1986, pp.95-97"/>

Chief Operations Specialist Larry Nowell, controlled more than 1500 intercepts aboard ''Mahan'' and ''Chicago'',<ref name="Nowell, April 1986, pp.95-97"/> and became one of the best known PIRAZ air controllers of the Vietnam War.<ref name="Mersky & Polmar 1981 p.192"/>  Chief Nowell provided air control information for more than 100 live engagements with enemy aircraft<ref name="Nowell, April 1986, pp.95-97"/> including 25 percent of intercepts leading to destruction of North Vietnamese fighters in 1972.  In August 1972, Chief Nowell became the second enlisted man in Navy history to be awarded the [[Navy Distinguished Service Medal|Distinguished Service Medal]].<ref>Smith 1998 p.62</ref>

==Search and Rescue==
One PIRAZ shipboard air controller was designated as "flight follower" for each Navy or Air Force formation of strike aircraft to track the strike's progress and offer information required to complete the mission.<ref name="Lockee, April 1969, p.146"/>  Flight followers worked with as many as 24 aircraft on a single frequency.<ref name="Nowell, April 1986, pp.95-97"/>  PIRAZ ships had the most recent position information for downed aircraft, and were often the closest surface force to a crash site.  All PIRAZ ships were equipped with landing platforms for [[SH-3 Sea King]] "Big Mother" or [[SH-2 Seasprite]] "Clementine" armored helicopters for Search and Rescue (SAR) work.<ref name="Cagle, May 1972, p.68"/><ref>Glickman, September 1972, pp.90–92</ref>  The weapons arrangement of Belknap class frigates was more favorable for helicopter operation, because helicopters on the [[poop deck|fantail]] landing platform would be damaged during missile firing from the stern launcher of [[Leahy class cruiser|''Leahy'']] and [[Farragut class destroyer (1958)|''Coontz'' class frigates]].  PIRAZ shipboard air controllers could provide positive control for SAR aircraft;<ref name="Bowman 1985 p.429"/> and PIRAZ ships could provide on-deck refueling service for Navy and Air Force helicopters.<ref name="Lockee, April 1969, p.146"/>

==Notes==
{{Reflist|2}}

==References==
* {{cite book |title=The Vietnam War Almanac |author=Bowman, John S. |publisher=World Almanac Publications |year=1985 |isbn=0-911818-85-5 |url=https://archive.org/details/vietnamwaralmana00bowm }}
* {{cite journal|author=Cagle, Malcolm W., VADM USN |title=Task Force 77 in Action Off Vietnam |publisher=United States Naval Institute Proceedings |date=May 1972}}
* {{cite book| title=One day in a long war: May 10, 1972, air war, North Vietnam |author1=Ethell, Jeffrey  |author2=Price, Alfred  |name-list-style=amp |publisher=Random House |year=1989 |isbn=0-394-57622-5}}
* {{cite book| title=Aces and aerial victories, the United States Air Force in Southeast Asia 1965–1973 |author=Futrell, Robert Frank, Eastman, James N., Hanak, Walter K., and Paszek, Laurence J.V. |publisher=U.S. Government Printing Office |year=1978}}
* Gargus, John, ''The Son Tay Raid: American POWs in Vietnam Were Not Forgotten'', Texas A&M University Press, 2007
* {{cite journal|author=Glickman, Thomas W., CDR USN |title=Comment and Discussion |publisher=United States Naval Institute Proceedings |date=September 1972}}
* {{cite journal|author=Lockee, Garette E., CAPT USN |title=PIRAZ |publisher=United States Naval Institute Proceedings |date=April 1969}}
* {{cite book |title=The Naval Air War in Vietnam |author1=Mersky, Peter B. |author2=Polmar, Norman |name-list-style=amp |publisher=The Nautical and Aviation Publishing Company of America |year=1981 |isbn=0-933852-13-4 |url=https://archive.org/details/navalairwarinvie00mers }}
* {{cite journal|author=Nowell, Larry H., OSC USN |title=Training Air Intercept Controllers for Battle |publisher=United States Naval Institute Proceedings |date=April 1986}}
* {{cite book| title = USS Chicago (CG-11) The Fourth Cruise |author=Odell, Charles, LTJG USN and Purves, William ENS, USNR |publisher=Walsworth Publishing Company |year=1971}}
* {{cite journal|author=Parker, Daniel M., CDR USN |title=The Empty Cockpit |publisher=United States Naval Institute Proceedings |date=August 1984}}
* {{cite book |title=Nixon's Trident: Naval Power in Southeast Asia, 1968–1972 |author=Sherwood, John Darrell |publisher=U.S. Government Printing Office |year=2009 |isbn=978-0-945274-58-2 |url-access=registration |url=https://archive.org/details/NixonsTrident }}
* {{cite book| title=The Linebacker Raids |author=Smith, John T. |publisher=Arms & Armour Press |year=1998 |isbn=1-85409-450-5}}

==External links==
*{{cite web
|access-date=2008-08-16
|url=http://www.uss-king.com/piraz.shtml
|title=PIRAZ – An Unclassified Summary Of PIRAZ (1968)
|author=Lockee, Captain G. E.
|year=1968
|archive-date=2011-07-22
|archive-url=https://web.archive.org/web/20110722213707/http://www.uss-king.com/piraz.shtml
|url-status=dead
}}

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