View source for Engineering:McDonnell Douglas T-45 Goshawk

{{short description|US carrier-based military training aircraft developed from British BAE Hawk}}
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{|{{Infobox aircraft begin
 |name= T-45 Goshawk
 |image= File:T-45A Goshawk 03.jpg
 |caption= The T-45A in flight
}}{{Infobox aircraft type
 |type= Naval [[Engineering:Trainer aircraft|trainer aircraft]]
 |national origin= United Kingdom/United States
 |manufacturer= [[Company:McDonnell Douglas|McDonnell Douglas]]/British Aerospace <br/>[[Company:Boeing|Boeing]]/BAE Systems
 |designer=
 |first flight= 16 April 1988<ref name="Donald 175"/>
 |introduced= 1991
 |retired=
 |status= In service
 |primary user= United States Navy
 |more users= <!--up to three more. please separate with <br/>.-->
 |produced= 1988-2009
 |number built= 221<ref>{{cite web |url=http://boeing.mediaroom.com/index.php?s=20295&item=1389 |title=Boeing, US Navy Celebrate T-45 Jet Trainer's Million-Flight-Hour Milestone |publisher=Boeing Defense, Space & Security |date=26 August 2010 |access-date=19 November 2013 |archive-url=https://web.archive.org/web/20141228174052/http://boeing.mediaroom.com/index.php?s=20295&item=1389 |archive-date=28 December 2014 |url-status=live}}</ref>
 |unit cost= 
 |developed from= [[Engineering:BAE Systems Hawk|BAE Systems Hawk]]
 |variants with their own articles= 
}}
|}

The '''McDonnell Douglas''' (now '''Boeing''') '''T-45 Goshawk''' is a highly modified version of the British [[Engineering:BAE Systems Hawk|BAE Systems Hawk]] land-based training [[Engineering:Jet aircraft|jet aircraft]]. Manufactured by [[Company:McDonnell Douglas|McDonnell Douglas]] (now [[Company:Boeing|Boeing]]) and British Aerospace (now BAE Systems), the T-45 is used by the United States Navy as an [[Engineering:Aircraft carrier|aircraft carrier]]-capable trainer.

==Development==
===Background===
The T-45 Goshawk has its origins in the mid-1970s, during which time the U.S. Navy formally commenced its search for a new jet trainer aircraft to serve as a single replacement for both its T-2 Buckeye and TA-4 Skyhawk trainers.<ref name= "gaines 21"/> During 1978, the VTXTS advanced trainer program to meet this need was formally launched by the U.S. Navy. An {{wipe|United Kingdom}}-{{wipe|United States}} team, comprising British aviation manufacturer British Aerospace (BAe) and American aircraft company [[Company:McDonnell Douglas|McDonnell Douglas]] (MDC), decided to submit their proposal for a navalised version of BAe's land-based [[Engineering:BAE Systems Hawk|Hawk]] trainer. Other manufacturers also submitted bids, such as a rival team of French aircraft company Dassault Aviation, German manufacturer Dornier and American aerospace company [[Company:Lockheed Corporation|Lockheed]], who offered their Alpha Jet to fulfil the requirement.<ref name= "gaines 21"/>

The VTX-TS competition was not simply for the procurement of an aircraft in isolation; it comprised five core areas: the aircraft itself, capable flight simulators, matured academic training aids, integrated [[Finance:Logistics|logistic]] support, and program management.<ref name= "gaines 21"/> For their proposal, MDC was the prime contractor and systems integrator, BAe functioned as the principal subcontractor and partner for the aircraft element, Rolls-Royce provided the Adour engine to power the aircraft, and [[Company:Sperry Corporation|Sperry]] is the principal subcontractor for the simulator system.<ref name= "gaines 21"/> During November 1981, the U.S. Navy announced that it had selected the Hawk as the winner of the VTX-TS competition.<ref name= "gaines 21">Gaines 1988, p. 21.</ref> Reportedly, approximately 60 per cent of the work on the T-45 program was undertaken overseas in Britain. During September 1982, a Full Scale Engineering Development contract was awarded to the MDC team to fully develop and produce the proposed aircraft, which had been designated ''T-45 Goshawk''.<ref name= "gaines 21"/> On 16 April 1988, the first T-45A Goshawk conducted its [[Engineering:Maiden flight|maiden flight]].<ref name= "mil dir 98"/>

===Production===
[[File:T-45A Goshawk 04.jpg|thumb|left|A pair of T-45A Goshawks during a training flight over Texas]]

Work on the production of the Goshawk was divided between the two primary partner companies. BAE Systems (BAe's successor following its merger with Marconi Electronic Systems during 1999) was responsible for manufacturing the fuselage aft of the cockpit, along with the [[Engineering:Intake#Aircraft intakes|air inlet]]s, and the vertical stabilizer of the T-45 at their Samlesbury facility, while the wings were produced at the company's plant at Brough, England. [[Company:Boeing|Boeing]] (which had merged with McDonnell Douglas during 1997) performed the manufacture of the remaining elements of the Goshawk, as well as conducting assembly of the type at a production line at St. Louis, Missouri, after having transferred work on the program from the company's facility in Long Beach, California.

The Goshawk retained the typical powerplant used by the Hawk, the Rolls-Royce Adour [[Engineering:Turbofan|turbofan]] jet engine.<ref>[https://www.flightglobal.com/news/articles/adour-variant-developed-for-bae-hawk-4886/ "Adour variant developed for BAe Hawk."] {{Webarchive|url=https://web.archive.org/web/20170916182835/https://www.flightglobal.com/news/articles/adour-variant-developed-for-bae-hawk-4886/ |date=16 September 2017}} ''Flight International'', 19 June 1997.</ref> During the mid-1990s, Rolls-Royce worked on establishing a US-based production line for the Adour engine, which was to be operated by the former Allison Engine Company (which had been recently acquired by Rolls-Royce in 1995); however, during September 1997, the U.S. Navy chose to terminate the partially-finished engine effort.<ref>[https://www.flightglobal.com/news/articles/usnavy-sinks-adour-plan-18848/ "USNavy sinks Adour plan."] {{Webarchive|url=https://web.archive.org/web/20170916225059/https://www.flightglobal.com/news/articles/usnavy-sinks-adour-plan-18848/ |date=16 September 2017}} ''Flight International'', 3 September 1998.</ref> Around this time, the U.S. Navy was greatly interested in potentially adopting another powerplant, the International Turbine Engine Company's F124 turbofan engine, for the Goshawk. On 7 October 1996, a T-45A test aircraft flew, powered by the rival F124 engine.<ref>Norris, Gug. [https://www.flightglobal.com/news/articles/f124-has-successful-t-45-debut-9582/ "F124 has successful T-45 debut."] {{Webarchive|url=https://web.archive.org/web/20170916182624/https://www.flightglobal.com/news/articles/f124-has-successful-t-45-debut-9582/ |date=16 September 2017}} ''Flight International'', 17 October 1996.</ref><ref>[https://www.flightglobal.com/news/articles/itec-ships-first-f124-turbofan-12423/ "ITEC ships first F124 turbofan."] {{Webarchive|url=https://web.archive.org/web/20170916182752/https://www.flightglobal.com/news/articles/itec-ships-first-f124-turbofan-12423/ |date=16 September 2017}} ''Flight International'', 10 July 1996.</ref>

Early production aircraft were designated ''T-45A''. From December 1997 onwards,<ref name= "mil dir 98">[https://www.flightglobal.com/news/articles/military-aircraft-directory-boeingbritish-aerospac-40218/ "Military Aircraft Directory: Boeing/British Aerospace."] {{Webarchive|url=https://web.archive.org/web/20170916182540/https://www.flightglobal.com/news/articles/military-aircraft-directory-boeingbritish-aerospac-40218/ |date=16 September 2017}} ''Flight International'', 29 July 1998.</ref> later-built production Goshawks were constructed with enhanced avionics systems, which included the adoption of a [[Engineering:Glass cockpit|glass cockpit]] and [[Head-up display|head-up display]] (HUD); as such, they were designated ''T-45C''.<ref name= "lobby 02"/><ref>[https://www.flightglobal.com/news/articles/us-navy-aims-for-cut-price-t-45s-35311/ "US Navy aims for cut-price T-45s."] {{Webarchive|url=https://web.archive.org/web/20170916225406/https://www.flightglobal.com/news/articles/us-navy-aims-for-cut-price-t-45s-35311/ |date=16 September 2017}} ''Flight International'', 8 April 1998.</ref> From 2003 onwards, all of the extant T-45A trainer aircraft were eventually converted to the more modern T-45C configuration under the T-45 Required Avionics Modernization Program. This program brought the U.S. Navy's trainers to an identical ''Cockpit 21'' standard, which incorporated both the HUD and the glass cockpit, which had the benefit of making the trainers more similar to the U.S. Navy's frontline fighter aircraft.<ref name= "lobby 02"/> On 16 March 2007, it was announced that the 200th Goshawk had been delivered to the U.S. Navy.<ref name=200th_delivery>[http://www.boeing.com/news/releases/2007/q1/070316a_nr.html "Boeing Delivers 200th T-45 Trainer to U.S. Navy"] {{webarchive|url=https://web.archive.org/web/20071011153715/http://boeing.com/news/releases/2007/q1/070316a_nr.html |date=11 October 2007}}. Boeing, 16 March 2007.</ref> During November 2009, the 221st aircraft, the final aircraft to be produced, was delivered.<ref>{{cite web |url=http://boeing.mediaroom.com/index.php?s=20295&item=1389 |title=Boeing, US Navy Celebrate T-45 Jet Trainer's Million-Flight-Hour Milestone |publisher=Boeing Defense, Space & Security |date=26 August 2010 |access-date=19 November 2013}}</ref>

===Further development===
During early 2008, it was announced by the US Navy that several of its T-45C Goshawks would be outfitted with a synthetic radar capability to allow them to support rear crew training requirements, and that it was considering a possible requirement for a follow-on order for such equipped models of the type.<ref name= "syn rad 08"/> An initial batch of 19 T-45Cs equipped with this virtual mission training system (VMTS), which simulates the capabilities of the US Navy's Boeing F/A-18E/F Super Hornet's Raytheon APG-73 radar (including ground mapping, air-to-ground and air-to-air targeting modes, along with an electronic warfare training capability) were delivered to the Navy's Undergraduate Military Flight Officer training school at Pensacola, Florida. The type was used to prepare weapon system and electronic warfare operators for the Super Hornet and the [[Engineering:Boeing EA-18G Growler|Boeing EA-18G Growler]].<ref name= "syn rad 08"/>

Both McDonnell Douglas and Boeing have made multiple approaches to potential overseas customers, typically offering the Goshawk in the trainer role. During the mid-1990s, McDonnell Douglas teamed up with [[Company:Rockwell International|Rockwell International]] to jointly bid the T-45 as a replacement for the {{wipe|Royal Australian Air Force}}'s jet trainer fleet in competition against, amongst others, the Hawk that the type had been derived from.<ref>[https://www.flightglobal.com/news/articles/mdc-joins-with-rockwell-to-offer-goshawk-to-the-raaf-24330/ "MDC joins with Rockwell to offer Goshawk to the RAAF."] {{Webarchive|url=https://web.archive.org/web/20170916182455/https://www.flightglobal.com/news/articles/mdc-joins-with-rockwell-to-offer-goshawk-to-the-raaf-24330/ |date=16 September 2017}} ''Flight International'', 6 September 1995.</ref> Marketing efforts to acquire export customers were intensified following a cut in the procurement rate by the U.S. Navy during 2003; according to Lon Nordeen, T-45 business development manager, [[Place:Israel|Israel]] had been identified as having a potential requirement for the type.<ref name= "lobby 02">Warwick, Graham. [https://www.flightglobal.com/news/articles/boeing-lobbies-to-restore-t-45-to-economic-level-140902/ "Boeing lobbies to restore T-45 to economic level."] {{Webarchive|url=https://web.archive.org/web/20170916053415/https://www.flightglobal.com/news/articles/boeing-lobbies-to-restore-t-45-to-economic-level-140902/ |date=16 September 2017}} ''Flight International'', 8 January 2002.</ref> During late 2006, the company promoted the concept of an advanced variant of the T-45C Goshawk to Greece, emphasising its close compatibility with the [[Engineering:Beechcraft T-6 Texan II|Beechcraft T-6A Texan II]] trainer already operated by the country.<ref>Hoyle, Craig. [https://www.flightglobal.com/news/articles/defendory-2006-improved-goshawk-aimed-at-athens-209895/ "Defendory 2006: Improved Goshawk aimed at Athens."] {{Webarchive|url=https://web.archive.org/web/20170916053915/https://www.flightglobal.com/news/articles/defendory-2006-improved-goshawk-aimed-at-athens-209895/ |date=16 September 2017}} ''Flight International'', 10 October 2006.</ref> During early 2007, Boeing VP Mark Kronenberg stated that the company had held discussions with the Indian Navy, which had an anticipated requirement for naval training aircraft.<ref>[https://www.flightglobal.com/news/articles/bangalore-air-show-boeing-to-offer-t-45s-212063/ "Bangalore air show: Boeing to offer T-45s."] {{Webarchive|url=https://web.archive.org/web/20170916054416/https://www.flightglobal.com/news/articles/bangalore-air-show-boeing-to-offer-t-45s-212063/ |date=16 September 2017}} ''Flight International'', 13 February 2007.</ref>

Starting in 2003, the Air Education and Training Command (AETC) of the {{wipe|United States Air Force}} (USAF) worked on the requirements for replacing the 1960s-era [[Engineering:Northrop T-38 Talon|Northrop T-38 Talon]] jet trainer. By 2010, the US Navy was reportedly involved in the evaluations for the initiative, known as the T-X program and had been considering the merits of adopting the same airframe to meet its long-term requirements to eventually replace the Goshawk as well.<ref name="preview">{{Citation |last= Trimble |first= Stephan |url= http://www.flightglobal.com/articles/2010/06/22/343393/us-air-force-industry-prepare-for-t-38-replacement.html |title= US Air Force, industry prepare for T-38 replacement |newspaper= Flight International |date= 22 June 2010 |access-date= 20 September 2010 |archive-url= https://web.archive.org/web/20101011112209/http://www.flightglobal.com/articles/2010/06/22/343393/us-air-force-industry-prepare-for-t-38-replacement.html |archive-date= 11 October 2010 |url-status= live}}.</ref> Reportedly, BAE Systems, later in partnership with American defense company [[Company:Northrop Grumman|Northrop Grumman]], has repeatedly held discussions with the USAF on the development of a new potential derivative of the Hawk conforming to their specific trainer needs, similar in fashion to the Goshawk for the US Navy.<ref>Hoyle, Craig. [https://www.flightglobal.com/news/articles/three-designs-to-contest-usafs-t-x-deal-believes-b-335673/ "Three designs to contest USAF's T-X deal, believes BAE."] {{Webarchive|url=https://web.archive.org/web/20170916054408/https://www.flightglobal.com/news/articles/three-designs-to-contest-usafs-t-x-deal-believes-b-335673/ |date=16 September 2017}} ''Flight International'', 2 December 2009.</ref><ref>Hemmerdinger, Jon. [https://www.flightglobal.com/news/articles/rivals-line-up-for-usaf-trainer-battle-397498/ "Rivals line up for USAF trainer battle."] {{Webarchive|url=https://web.archive.org/web/20170916052917/https://www.flightglobal.com/news/articles/rivals-line-up-for-usaf-trainer-battle-397498/ |date=16 September 2017}} ''Flight International'', 27 March 2014.</ref>

==Design==
The T-45 Goshawk is a carrier-qualified version of the British Aerospace Hawk Mk.60.<ref name="Donald 175">Donald 2004, p. 175.</ref><ref name="Frawley 48">Frawley 2002, p. 48.</ref> It was redesigned as a trainer for the United States Navy (USN) and United States Marine Corps (USMC). Changes were made to the Hawk in two stages. The Hawk was redesigned for carrier operations and submitted to the Navy for flight evaluation. The development flight trials resulted in further modifications. 

The initial redesign included stronger landing gear and airframe to withstand the loads imposed by catapult launches and high sink-rate (14 ft/sec<ref>https://www.aerosociety.com/publications/jah-the-hawk-story/ p. 92.</ref>) landings. A catapult tow bar attachment was added to the oleo strut of the new two-wheel nose gear .<ref name="usn_file">[http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=2000&ct=1 "T-45A fact file."] {{Webarchive |url=https://web.archive.org/web/20070205025859/http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=2000&ct=1 |date=5 February 2007}} ''US Navy'', Retrieved: 15 September 2017.</ref><ref name= "gaines 24"/>  Other additions were an arresting hook, an increased span tailplane, side-mounted airbrakes, and the addition of stabilator vanes, known as 'Side Mounted Upper Rear Fuselage [[Engineering:Strake (aeronautics)|Strake]]s' (SMURFS - USN), to stabilize flow over the stabilator with speed brakes extended.<ref>Flight Training Instruction Aerodynamics Workbook T-45,CNATRAP-1231 (Rev.08-09) 2009,Naval Air Training Command,United States Navy, Figure3-10</ref>

Navy test pilots found deficiences which had to be corrected. Some required further external changes: a single ventral fin in front of the arrestor hook, a 6-inch (0.152 m) extension to the tail fin, squared-off wing tips and [[Engineering:Leading-edge slat|leading-edge slat]]s.<ref name=":0">{{Cite web |url=http://www.aeroflight.co.uk/aircraft/types/boeing-bae-systems-t-45-goshawk.htm |title=Boeing/BAE Systems T-45 Goshawk Aircraft Profile |date=23 December 2010 |website=Aeroflight |publisher=aeroflight.co.uk |access-date=2 May 2016 |archive-url=https://web.archive.org/web/20160406184814/http://www.aeroflight.co.uk/aircraft/types/boeing-bae-systems-t-45-goshawk.htm |archive-date=6 April 2016 |url-status=dead}}</ref>

At the time of the Goshawk's selection, the [[Social:World War II|World War II]]-era USS ''Lexington'' was the U.S. Navy's training carrier. ''Lexington'', which featured a 910&nbsp;ft-long and 192&nbsp;ft-wide angled flight deck, complete with a pair of relatively short-stroke steam catapults and similarly short, undamped arrester gear, was a major driving factor for the design of the T-45 in order to suit such operations.<ref name= "gaines 24">Gaines 1988, p. 24.</ref> The aerodynamic changes of the aircraft, which were developed by BAe at their existing facilities in the United Kingdom, included improvements to the low-speed handling characteristics and a reduction in the approach speed. During flight testing of the Goshawk, it was revealed that the aircraft had retained relatively favourable flight characteristics, even when flown within [[Physics:Stall (fluid mechanics)|stall]] conditions at the required low approach speed.<ref name="VectorSite">Goebel, Greg, [http://www.vectorsite.net/avhawk.html#m4 "T-45 Goshawk"] {{Webarchive|url=https://web.archive.org/web/20120107035103/http://vectorsite.net/avhawk.html#m4 |date=7 January 2012}}. VectorSite.net, 1 March 2006.</ref>

==Operational history==
[[File:US Navy 100205-N-9928E-178 apt. Joseph W. Kuzmick, from Bremerton, Wash., commanding officer of the Nimitz-class aircraft carrier USS John C. Stennis (CVN 74), launches from the ship in a T-45C Goshawk.jpg|thumb|A T-45 Goshawk being launched from {{USS|John C. Stennis|CVN-74|6}} in 2010]]
[[File:Flickr - Official U.S. Navy Imagery - A T-45C Goshawk training aircraft makes an arrested landing.jpg|thumb|A T-45 Goshawk making an arrested landing on {{USS|Dwight D. Eisenhower|CVN-69|6}} in 2011]]

The T-45 has been used for intermediate and advanced portions of the Navy/Marine Corps Student Naval Aviator strike pilot training program with Training Air Wing One at Naval Air Station Meridian, Mississippi, and Training Air Wing Two at Naval Air Station Kingsville, Texas.  The T-45 replaced the T-2C Buckeye intermediate jet trainer and the TA-4J Skyhawk II advanced jet trainer with an integrated training system that includes the T-45 Goshawk aircraft, operational and instrument flight simulators, academics, and training integration system support. In 2008, the T-45C also began operation in the advanced portion of Navy/Marine Corps Student Naval Flight Officer training track for strike aircraft with Training Air Wing Six at Naval Air Station Pensacola, Florida.  A small number of the aircraft is also operated by the Naval Air Systems Command at [[Engineering:Naval Air Station Patuxent River|Naval Air Station Patuxent River]], Maryland.

The original T-45A, which became operational in 1991, contained an analog cockpit design, while the newer T-45C, which was first delivered in December 1997, features a new digital "glass cockpit" design. All T-45A aircraft currently in operational use are upgraded to T-45C standard.  The T-45 is to remain in service until 2035 or later.<ref name=200th_delivery/>

In 2017, the USN grounded the T-45 fleet for a three-day "safety pause" after more than 100 instructor pilots refused to fly the aircraft. The pilots cited concerns about incidents of [[Medicine:Hypoxia (medical)|hypoxia]] that they believed to have resulted from faulty Cobham GGU-7 onboard oxygen-generation systems.<ref>{{Cite news |last=Tomlinson |first=Lucas |date=4 April 2017 |title=Navy Instructor Pilots Refusing to Fly Over Safety Concerns |work=Military.com |agency=Fox News |url=http://www.military.com/daily-news/2017/04/05/navy-instructor-pilots-refusing-fly-safety-concerns.html |url-status=live |access-date=2017-04-06 |archive-url=https://web.archive.org/web/20170406001237/http://www.military.com/daily-news/2017/04/05/navy-instructor-pilots-refusing-fly-safety-concerns.html |archive-date=6 April 2017}}</ref><ref>{{Cite news |last=Seck |first=Hope Hodge |date=5 April 2017 |title=Navy Announces Three-Day Grounding for T-45s After Pilot Strike |work=Military.com |url=http://www.military.com/daily-news/2017/04/05/navy-announces-two-day-grounding-t45s-pilot-strike.html |url-status=live |access-date=2017-04-06 |archive-url=https://web.archive.org/web/20170406113805/http://www.military.com/daily-news/2017/04/05/navy-announces-two-day-grounding-t45s-pilot-strike.html |archive-date=6 April 2017}}</ref>  Over the past five years physiological episodes linked to problems with the T-45's oxygen system have nearly quadrupled, according to testimony from senior naval aviators in April 2017.<ref>{{Cite news |url=http://www.foxnews.com/politics/2017/04/08/navy-says-t-45-jets-grounded-indefinitely-following-fox-news-exclusive.html |title=NAVY says T-45 jets grounded indefinitely, following Fox News exclusive |date=2017-04-08 |work=Fox News |access-date=2017-04-09 |archive-url=https://web.archive.org/web/20170410052110/http://www.foxnews.com/politics/2017/04/08/navy-says-t-45-jets-grounded-indefinitely-following-fox-news-exclusive.html |archive-date=10 April 2017 |url-status=live}}</ref> The grounding order was first extended, but then lifted<ref>{{Cite news |url=http://www.navytimes.com/news/your-navy/2017/06/12/grounded-training-jets-could-lead-to-collaboration-between-navy-and-air-force/ |title=Grounded training jets could lead to collaboration between Navy and Air Force |date=2017-06-12 |work=Navy Times |access-date=2017-08-18}}</ref> to allow flights up to a ceiling of 10,000 feet where the Onboard Oxygen Generation System (OBOGS) would not be needed, and to allow instructors to conduct flights above 10,000 feet.<ref>{{Cite news |url=http://hrana.org/news/2017/04/us-navy-lifts-goshawk-grounding-though-restrictions-remain/ |title=US Navy lifts Goshawk grounding, though restrictions remain |date=2017-04-19 |work=Association of Naval Aviation : Hampton Roads Squadron |access-date=2019-03-30 |archive-url=https://web.archive.org/web/20190330182322/http://hrana.org/news/2017/04/us-navy-lifts-goshawk-grounding-though-restrictions-remain/ |archive-date=30 March 2019 |url-status=live}}</ref> The grounding order was fully lifted, along with all restrictions on flight ceiling and student pilots, in August 2017.<ref>{{Cite news |url=https://www.thedrive.com/the-war-zone/14814/t-45-trainer-crashes-in-tennessee-just-weeks-after-grounding-was-lifted |title=T-45 Trainer Crashes In Tennessee Just Weeks After Grounding Was Lifted |date=2017-10-02 |work=The Drive : The Warzone |access-date=2019-03-30 |archive-url=https://web.archive.org/web/20190330182320/https://www.thedrive.com/the-war-zone/14814/t-45-trainer-crashes-in-tennessee-just-weeks-after-grounding-was-lifted |archive-date=30 March 2019 |url-status=live}}</ref> The T-45 fleet was thereafter upgraded with new sensors to monitor the onboard oxygen systems, as well as a new water separation system, in hopes of reducing hypoxia events and determining the root cause of the problems.<ref>{{Cite news |url=https://www.defensenews.com/air/2017/12/13/t-45s-to-get-new-oxygen-monitoring-system-by-february/ |title=T-45s to get new oxygen monitoring system by February |date=2017-12-13 |work=Defense News |access-date=2019-03-30}}</ref><ref>{{Cite news |url=https://www.flightglobal.com/news/articles/navy-trainers-resume-flying-with-oxygen-monitoring-u-441678/ |title=Navy trainers resume flying with oxygen monitoring upgrades |date=2017-09-30 |work=Flight Global |access-date=2019-03-30 |archive-url=https://web.archive.org/web/20190330182321/https://www.flightglobal.com/news/articles/navy-trainers-resume-flying-with-oxygen-monitoring-u-441678/ |archive-date=30 March 2019 |url-status=live}}</ref> By the first quarter of 2018, hypoxia events had returned to nominal levels after peaking in 2016 and 2017.<ref>{{Cite news |url=https://www.navytimes.com/naval/2018/03/08/the-rate-of-oxygen-loss-events-in-the-navys-training-jets-has-plummeted-in-the-last-6-months/ |title=The rate of oxygen loss events in the Navy's training jets has plummeted in the last 6 months |date=2018-03-08 |work=Navy Times |access-date=2019-03-30}}</ref><ref>{{Cite news |url=https://www.upi.com/Boeing-contracted-for-T-45-backup-oxygen-systems/6311532437676/ |title=Boeing contracted for T-45 backup oxygen systems |date=2018-07-24 |work=UPI |access-date=2019-03-30 |archive-url=https://web.archive.org/web/20190330182321/https://www.upi.com/Boeing-contracted-for-T-45-backup-oxygen-systems/6311532437676/ |archive-date=30 March 2019 |url-status=live}}</ref> The fleet was later fitted with Cobham's revised GGU-25 onboard oxygen generating systems.<ref>{{Cite web |last=Pawlyk |first=Oriana |date=2021-03-09 |title=Navy's Whole T-45 Trainer Fleet to Get New Oxygen Systems After Hypoxia-Like Events |url=https://www.military.com/daily-news/2021/03/09/navys-whole-t-45-trainer-fleet-get-new-oxygen-systems-after-hypoxia-events.html |access-date=2023-12-23 |website=Military.com |language=en}}</ref>

In recent years, similar issues have also affected the Navy's F/A-18s and the Air Force's T-6s, F-22s, and F-35s,<ref>{{Cite news |url=https://www.pnj.com/story/news/military/2018/03/10/military-still-cant-figure-out-hypoxia-mystery/341859002/ |title=Military pilots' hypoxia episodes still a mystery |date=2018-03-10 |work=UPI |access-date=2019-03-30 |archive-url=https://web.archive.org/web/20190330182322/https://www.pnj.com/story/news/military/2018/03/10/military-still-cant-figure-out-hypoxia-mystery/341859002/ |archive-date=30 March 2019 |url-status=live}}</ref> some within the same or similar time frames, and the Department of Defense has established a joint command to investigate the issue.

On 14 October 2022, the Navy's T-45 fleet was grounded following a low-pressure compressor blade fault being identified during a pre-flight check. The grounding was lifted after two weeks.<ref>{{cite news |last1=Ziezulewicz |first1=Geoff |title=Here's why Navy and Marine Corps training jets are grounded |url=https://www.defensenews.com/news/your-navy/2022/10/24/heres-why-navy-and-marine-corps-training-jets-are-grounded/ |work=Defense News |date=24 October 2022 |language=en}}</ref><ref>{{Cite web |last=Ziezulewicz |first=Geoff |date=2022-11-01 |title=Navy ends safety standdown for part of the T-45C Goshawk jet fleet |url=https://www.navytimes.com/news/your-navy/2022/11/01/navy-ends-safety-standdown-for-part-of-the-t-45c-goshawk-jet-fleet/ |access-date=2023-12-23 |website=Navy Times |language=en}}</ref>

==Variants==
;T-45A
:Two-seat basic and advanced jet trainer for the US Navy and US Marine Corps

;T-45B
:Proposed land-based version which would have been essentially a conventional Hawk furnished with a US Navy-spec cockpit and no carrier capability. The US Navy had wanted to procure the T-45B so that trainee pilots could benefit from an earlier training capability, but abandoned the idea during 1984 in favor of less-costly updates to the TA-4J and T-2C.

;T-45C
:Improved T-45A, outfitted with a [[Engineering:Glass cockpit|glass cockpit]], inertial navigation, and other improvements. All existing T-45As have been upgraded to the T-45C standard.<ref>[http://www.defenseindustrydaily.com/us-carrier-pilots-t45-training-system-updated-03022/ "US Carrier Pilots’ T-45 Training System."] {{Webarchive|url=https://web.archive.org/web/20110526130923/http://www.defenseindustrydaily.com/us-carrier-pilots-t45-training-system-updated-03022/ |date=26 May 2011}} ''Defense Industry Daily'', 19 April 2017.</ref>

;T-45D
:Tentative designation for an envisioned upgrade of the T-45, potentially incorporating various manufacturing improvements and additional equipment, such as [[Engineering:Helmet-mounted display|helmet-mounted display]]s.<ref name= "syn rad 08">Hoyle, Craig. [https://www.flightglobal.com/news/articles/us-navy-to-add-synthetic-radar-to-goshawk-eyes-t-45d-222378/ "US Navy to add synthetic radar to Goshawk, eyes T-45D."] {{Webarchive|url=https://web.archive.org/web/20170916011211/https://www.flightglobal.com/news/articles/us-navy-to-add-synthetic-radar-to-goshawk-eyes-t-45d-222378/ |date=16 September 2017}} ''Flight International'', 24 March 2008.</ref><ref>Hoyle, Craig. [https://www.flightglobal.com/news/articles/bae-systems-promotes-major-upgrade-programme-for-haw-225235/ "BAE Systems promotes major upgrade programme for Hawk."] {{Webarchive|url=https://web.archive.org/web/20170916054456/https://www.flightglobal.com/news/articles/bae-systems-promotes-major-upgrade-programme-for-haw-225235/ |date=16 September 2017}} ''Flight International'', 15 July 2008.</ref>

==Operators==
[[File:US Navy 050624-N-0535P-006 A T-45A Goshawk trainer aircraft assigned to Training Air Wings One and Two cover the flight deck aboard the Nimitz-class aircraft carrier USS Harry S. Truman (CVN 75).jpg|thumb|T-45 Goshawks on board {{USS|Harry S. Truman|CVN-75|6}} in 2005]]

;{{flagu|United States}}
* United States Navy: T-45C

==Accidents==
As of August 2022, about 33 T-45 Goshawks have been destroyed in accidents, or about 15% of the inventory, at a rate of about 1 per year.

==Specifications (T-45A)==
{{Aircraft specs
|ref= ''The International Directory of Military Aircraft, 2002–2003,''<ref name="Frawley 48"/> ''Navy fact file'',<ref name="usn_file"/> ''T-45A/C Goshawk,''<ref name="navtrech">{{cite web |title=T-45A/C Goshawk |url=http://www.naval-technology.com/projects/t45/ |website=Naval Technology |access-date=31 March 2020}}</ref> ''Jane's All the World's Aircraft 2005-06'' <ref name=JAWA2005-2006>{{cite book |title=Jane's All the World's Aircraft 2005-06 |editor1-last=Jackson |editor1-first=Paul |year=2005 |publisher=Jane's Publishing Group |location=London |isbn=9780710626844 |edition=96th|pages=263–264}}</ref>
|prime units?=kts
<!--  General characteristics
-->
|crew=2
|length ft=39
|length in=4
|length note=
|span ft=30
|span in=9.75
|span note=
|height ft=13
|height in=6
|height note=
|wing area sqft=190.1
|wing area note=
|aspect ratio=<!-- sailplanes -->
|airfoil='''root:''' Hawker 10.9%; '''tip:''' Hawker 9%<ref name="Selig">{{cite web |last1=Lednicer |first1=David |title=The Incomplete Guide to Airfoil Usage |url=https://m-selig.ae.illinois.edu/ads/aircraft.html |website=m-selig.ae.illinois.edu |access-date=16 April 2019}}</ref>
|empty weight lb=9394
|empty weight note=
|gross weight lb=12750
|gross weight note=
|max takeoff weight lb=13500
|max takeoff weight note=
|fuel capacity={{cvt|432|USgal|impgal l}} / {{cvt|3159|lb|0}} internal fuel ({{cvt|2893|lb|0}} - early production aircraft), with provision for 2x {{cvt|156|USgal|impgal l}} drop tanks underwing
|more general=
<!--  Powerplant
-->
|eng1 number=1
|eng1 name=Rolls-Royce Turbomeca F405-RR-401
|eng1 type=[[Engineering:Turbofan|turbofan]] engine
|eng1 lbf=5527
|eng1 note=de-rated (nominal thrust {{cvt|5845|lbf|2}})
<!--  Performance
-->
|max speed kts=543
|max speed note=at {{cvt|8000|ft}}
::::M0.84 at {{cvt|30000|ft}}
*'''Carrier launch speed:''' {{cvt|121|kn|mph km/h}}
*'''Approach speed:''' {{cvt|125|kn|mph km/h}}
|max speed mach=
|cruise speed kts=
|cruise speed note=
|stall speed kts=
|stall speed note=
|never exceed speed kts=575
|never exceed speed note= / M1.04 design dive limit at {{cvt|10000|ft}}
|range nmi=700
|range note=
|combat range nmi=
|combat range note=
|ferry range nmi=700
|ferry range note=
|endurance=<!-- if range unknown -->
|ceiling ft=42500
|ceiling note=
|g limits=<big>+</big>7.33 <big>-</big>3
|roll rate=<!-- aerobatic -->
|climb rate ftmin=8000
|climb rate note=at sea level
|time to altitude={{cvt|30000|ft}} in 7 minutes 40 seconds
|lift to drag=
|wing loading lb/sqft=67.1
|wing loading note=
|fuel consumption lb/mi=
|thrust/weight=0.41

|more performance=<br/>
*'''Take-off distance to {{cvt|50|ft|0}}:''' {{cvt|3610|ft}}
*'''Landing distance from {{cvt|50|ft|0}}:''' {{cvt|3310|ft}}
<!--  Armament
-->
|armament=
*Usually none: One hardpoint under each wing can be used to carry practice bomb racks (can carry up to 12 Mk-76 practice bombs), rocket pods, or fuel tanks. A centerline hardpoint can carry a cargo pod for crew baggage.
|avionics = 
*Smiths Industries, Ltd. AN/USN-2(V) Standard Attitude Heading and Reference System, later replaced by the BAE/Marconi AN/ASN-180 Navigation Guidance System
*[[Company:Rockwell Collins|Rockwell Collins]] AN/ARN-144 VHF [[Radio navigation|Omnidirectional Radio Range]] / Instrument Landing System
*[[Company:Honeywell|Honeywell]] AN/APN-194 [[Earth:Radar altimeter|Radar altimeter]]
*[[Company:Northrop Grumman|Northrop Grumman]] AN/ASN-166 [[Earth:Inertial navigation system|Inertial Guidance Set]] [http://www.designation-systems.net/usmilav/jetds/an-asn.html] Incorporates a Northrop Grumman (formerly [[Company:Litton Industries|Litton]]) LN-100G [[Physics:Ring laser gyroscope|ring laser gyroscope]], a Rockwell Collins [[Engineering:Global Positioning System|Global Positioning System]], and a [[Kalman filter]]
;Communications suite
*[[Company:Rockwell Collins|Rockwell Collins]] AN/ARC-182 UHF/VHF radio
*[[Company:Honeywell|Honeywell]] AN/APX-100 [[Identification friend or foe|identification friend or foe]] system
}}

==See also==
{{externalimage|topic=Hi-res cutaway of T-45 Goshawk|width= |float=right
|image1=[https://web.archive.org/web/20121023001939/http://www.flightglobal.com/airspace/media/militaryaviation1946-2006cutaways/images/10815/bae-mcdd-t-45a-cutaway.jpg Hi-res cutaway of T-45 Goshawk] by Flight Global.
}}

{{aircontent
|related=
* [[Engineering:BAE Systems Hawk|BAE Systems Hawk]]
* [[Engineering:British Aerospace Hawk 200|British Aerospace Hawk 200]]
|similar aircraft=
* [[Engineering:Lockheed T2V SeaStar|Lockheed T2V/T-1 SeaStar]]
* [[Engineering:Douglas A-4 Skyhawk|McDonnell Douglas TA-4F/J Skyhawk]]
* [[Engineering:North American T-2 Buckeye|North American T-2 Buckeye]]
* Sukhoi Su-25UTG
|lists=
* List of active United States military aircraft
}}

==References==
===Citations===
{{reflist|35em}}

===Bibliography===
{{refbegin|45em}}
* Donald, David. ''Warplanes of the Fleet''. AIRtime Publishing Inc, 2004. {{ISBN|1-880588-81-1}}.
* Frawley, Gerard. ''The International Directory of Military Aircraft''. Aerospace Publications Pty Ltd, 2002. {{ISBN|1-875671-55-2}}.
* Gaines, Mike. [http://www.flightglobal.com/pdfarchive/view/1988/1988%20-%200588.html "T-45 – Tailhook Trainer."] ''Flight International'', 12 March 1988. pp.&nbsp;20–25.
{{refend}}

==External links==
*[http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=2000&ct=1 T-45 Goshawk US Navy fact file] {{Webarchive|url=https://web.archive.org/web/20070205025859/http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=2000&ct=1 |date=5 February 2007}} and [http://www.history.navy.mil/planes/t45.htm T-45 US Navy history page] {{Webarchive|url=https://web.archive.org/web/20071223022803/http://www.history.navy.mil/planes/t45.htm |date=23 December 2007}}
*[https://web.archive.org/web/20120105020100/http://www.boeing.com/defense-space/military/t45/index.htm T-45 Goshawk page] and [https://web.archive.org/web/20061206124931/http://www.boeing.com/history/mdc/goshawk.htm T-45 Goshawk history page on Boeing.com]
*[https://web.archive.org/web/20100116074823/http://www.vectorsite.net/avhawk.html BAE Hawk at Greg Goebel's AIR VECTORS]
*[http://www.globalsecurity.org/military/systems/aircraft/t-45.htm T-45 Goshawk page on GlobalSecurity.org]
*[http://www.aeroflight.co.uk/types/usa/boeing/t-45/T-45.htm Boeing/BAE SYSTEMS T-45 Goshawk page on Aeroflight.co.uk]
*[http://www.naval-technology.com/projects/t45/ T-45A/C Goshawk page on Naval-Technology.com]
*[http://www.fas.org/programs/ssp/man/uswpns/air/trainer/t45.html FAS Page on the T-45]
*[https://web.archive.org/web/20120105020100/http://www.boeing.com/defense-space/military/t45/index.htm Boeing Page on the T-45TS&nbsp;– the T-45 Training System]
*[http://www.aeroflight.co.uk/aircraft/types/boeing-bae-systems-t-45-goshawk.htm Aeroflight Boeing/BAE Systems T-45 Goshawk Aircraft Profile]

{{McDD aircraft}}

[[Category:Carrier-based aircraft]]
[[Category:Low-wing aircraft]]
[[Category:Single-engined jet aircraft]]

{{Sourceattribution|McDonnell Douglas T-45 Goshawk}}