Raytheon’s APG-79 AESA Radars
May 15, 2011 14:38 EDT
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42 radars to equip FY 2011 aircraft; article enhancements. (May 13/11)
The AN/APG-79 Active Electronically Scanned Array (AESA) radar began life as a retrofit. Initial F/A-18 E/F Super Hornet production batches installed Raytheon’s all-weather, multimode AN/APG-73, but the APG-79 has intrinsic technical features that offered revolutionary increases in capability, reliability, image resolution, and range.
Unlike the “mechanically scanned” APG-73, the APG-79’s AESA array is composed of numerous solid-state transmit and receive modules that are fixed in place, eliminating a common cause of breakdowns. Other system components include an advanced receiver/exciter, ruggedized commercial-off-the-shelf (COTS) processor, and power supplies. With its open systems architecture and compact COTS parts, it changes what the aircrew can do with the radar – and does so in a smaller, lighter package…
- The AN/APG-79 AESA Radar [updated]
- Contracts & Key Events [updated]
- Additional Readings
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The downside of AESA radars is that they cost more to buy. The cost of producing all those transmit/receive (T/R) modules has come down, but it’s still a more expensive choice initially. On the other hand, AESA radars offer a number of performance advantages, and appear to be cheaper over the fighter’s entire lifespan.
Featuring a fixed array with active electronic beam scanning that scans near the speed of light, AESA radars let pilot and crew conduct simultaneous air-to-air and air-to-surface operations, something previous radars could not do. Performance also improves within each mode. In air-to-air mode, the radar’s improved sensitivity can allow targets to be engaged at longer ranges. If political Rules of engagement permit, fighters can launch at maximum range, taking full advantage of new longer-range air-air missiles and air-ground weapons. In air-to-surface mode, the system also offers high-resolution ground mapping at long standoff ranges. Its high-resolution SAR (synthetic aperture radar) images can be used to designate multiple targets at once, identify unplanned ground targets and engage them, and sort fast-moving vaval targets more effectively amidst the clutter created by waves and weather. With the previous APG-73 radar, only pre-planned ground targets, entered into the system before the mission began, could be attacked at full capability.
AESA radars have a number of additional advantages, some of which are being publicized as time goes on.
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One set of advantages involves long-term costs. Unlike predecessor radars like the mechanically scanned APG-73, American AESA designs to date have no moving parts to serve as sources of failure. Better yet, AESA radars’ inherent redundancy allows them to fly and perform well even if some of the individual T/R modules need replacing. Raytheon touts a 10x – 15x improvement in overall reliability, and experience with longer-serving AESA designs suggests that most AESA radars may even last for the life of their fighters, without significant maintenance. Since fighters may take 30 years to exhaust 10,000 flight hours, the maintenance savings make AESA radars a cheaper long-term option, in exchange for higher up-front investment.
The final set of advantages involves entirely new roles. AESA arrays’ depth of individually programmable T/R modules gives them the potential to perform offensive electronic warfare functions, high-bandwidth communications, and probably a few more capabilities that the government prefers not to talk about yet.
Since the original contract award in 2001, the APG-79 program has met all its milestones on time, and the system has performed well in flight tests.
In April 2005, Boeing and Raytheon debuted an F/A-18F Block II Super Hornet equipped with the AN/APG-79 AESA radar system at a St. Louis ceremony. That was the first step toward fulfilling the Navy’s roadmap to expand the F/A-18E/F Super Hornet family’s future capabilities. In October 2006, the first Super Hornet Block II squadron attained the requisite “safe for flight” designation, certifying that they were ready for independent operations with the new equipment.
Production installations and retrofits have continued. The AN/APG-79 will replace Raytheon’s own AN/APG-73 on early produciton F/A-18 E/F Super Hornet Block II aircraft, and equip the derivative EA-18G “Growler” electronic warfare aircraft as they enter service.
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At present, the AN/APG-79 appears destined to equip only F/A-18 Super Hornet family aircraft. Technologies from this radar have found their way into the AN/APG-82v1 radars that will be retrofitted to USAF F-15E Strike Eagles. Raytheon’s resizable RACR AESA radar also owes the APG-79 a debt. It’s aimed at the retrofit market for F-16s and F/A-18 Hornets around the world, and has been considered for new planes like the JAS-39 Gripen New Generation.
The U.S. Navy plans to buy over 400 AN/APG-79 AESA systems, and potential foreign sales span 7 countries now using the F/A-18 aircraft. Australia’s purchase of 24 F/A-18F Block II aircraft made them the radar’s first foreign customer.
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Unless otherwise indicated, all contracts are issued by the Naval Air Systems Command (NAVAIR) in Patuxent River, MD to Boeing subsidiary McDonnell Douglas Corp. in St. Louis, MO, It’s Raytheon’s radar, but Boeing is the lead contractor for the aircraft, and assumes overall responsibility for buying the radars and integrating them into the aircraft. Workshare in “El Segundo, CA,” for instance, is actually Raytheon’s.
Nov 22/11: Raytheon announces the delivery of its 300th AN/APG-79 radar to Boeing, for integration on U.S. Navy and RAAF Super Hornet family fighters.
May 13/11: Raytheon announces a contract from Boeing for 42 APG-79 radars, to equip Super Hornet family aircraft bought in the 2nd year of the 2010-2013 Multi-Year III program.
Work will be performed at Raytheon facilities in El Segundo, CA; Andover, MA; Forest, MS; and Dallas, TX.
May 2/11: A $12.6 million cost-plus-fixed-fee order for one-time engineering work associated with Engineering Change Proposal 6381 re: the AN/APG-79’s General Purpose Processor 3, and for the purchase of 12 engineering development modules.
Work will be performed in El Segundo, CA (65%); Forest, MS (20%); and St. Louis, MO (15%). Work is expected to be complete in January 2012 (N00019-11-G-0001).
Nov 30/10: A $17 million ceiling priced order for AN/APG-79 radar repairs. Work will be performed in Forest, MS, and is expected to be complete by June 2012. This contract was not competitively procured by the US Naval Inventory Control Point in Philadelphia, PA (N00383-10-G-005H, #0001).
Nov 16/10: Raytheon Space and Airborne Systems in El Segundo, CA receives a $52.25 million firm-fixed-price contract modification for 19 AN/APG-79 AESA radars, to be retrofitted into F/A-18E/F aircraft Lots 26-29.
Work will be performed in Forest, MS (43%); Dallas, TX (29%); El Segundo, CA (27%); and Andover, MA (1%). Work is expected to be complete in December 2013. Raytheon’s release adds that: “This third retrofit contract brings orders for the update of block II F/A-18s up to 57.”
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July 21/10: Raytheon announces that it has delivered is 200th APG-79 AESA radar to Boeing.
April 8/10: Raytheon Co. Space and Airborne Systems in El Segundo, CA received an $5.8 million delivery order against a previously issued basic ordering agreement (N00019-05-G-0008) for procurement of 2 AN/APG-79 AESA test radar for the F/A-18E/F and EA-18G aircraft.
Work will be performed in Forest, MS (45%), El Segundo, CA (35%), and Andover, MA (15%), and Dallas, TX (5%) and is expected to be complete in November 2011.
April 5/10: A $13.6 million cost-plus-fixed-fee delivery order against a previously issued Basic Ordering Agreement (N00019-05-G-0026) to complete the AESA waveform generator DDS II die parts obsolescence redesign engineering change proposal for the F/A-18 E/F aircraft.
Work will be performed in El Segundo, CA (87.7%), and St. Louis, MO (12.3%), and is expected to be complete in March 2011.
March 24/10: From FedBizOpps, solicitation #20047-10 deals with a reality of modern equipment. The equipment lasts long after the underlying electronics are completely obsolete. Imagine if your computer went 15 years without an upgrade. The USAF experiences that as an ongoing reality, for even longer periods. For the APG-79:
“The Naval Air Systems Command has a requirement for an engineering change to the AN/APG-79 Active Electronically Scanned Array (AESA).... upgrades the general purpose processor in order to support additional capability requirements. The AESA prime integrator is The Boeing Company, St. Louis, MO. The Navy intends to negotiate the engineering change as a sole source firm fixed price delivery order to the F/A-18 & EA-18G Basic Ordering Agreement with Boeing. Boeing will be responsible for the non-recurring and recurring engineering changes. Award of the delivery order will be made with authority under FAR 6.302-1, only one responsible source and no other supplies or services will satisfy agency requirements. Boeing has the requisite RADAR knowledge, experience, and technical data required to respond to this requirement. This notice of intent is not a request for competitive proposals.”
The result will almost certainly be a sub-contract to the radar’s manufacturer, Raytheon, but as noted above, Boeing owns final engineering responsibility.
Oct 7/09: Raytheon Space and Airborne Systems in El Segundo, CA received a $5.7 million modification to a previously awarded firm-fixed-price contract (N00019-04-C-0014) to perform engineering change proposal 6279. This will enhance the AN/APG-79 active electronically scanned array radar on a number of Lot 33 production aircraft: 14 F/A-18Es, 9 of th 2-seat F/A-18Fs, and 22 EA-18G Growler electronic attack aircraft.
Work will be performed in Forest, MS (42%); El Segundo, CA (36.8%); and St. Louis, MO (21.2%), and is expected to be complete in September 2011.
April 2/09: Raytheon Co., Space and Airborne Systems in El Segundo, CA received a $54.5 million firm-fixed-price contract for 19 AN/APG-79 active array radars. The radars will be retrofitted into F/A-18E/F Super Hornet aircraft built during Lots 26-29. The radars will replace the mechanically-scanned APG-73 phased array radars currently installed in the aircraft.
Work will be performed in Forest, MS (43%); Dallas, TX (29%); El Segundo, CA (27%); and Andover, MA (1%) and is expected to be complete in December 2010. This contract was not competitively procured (N00019-09-C-0003).
As of Raytheon’s May 26/09 release, the firm had delivered 134 APG-79 radars to the Navy for use in F/A-18 Super Hornet and EA-18G Growler aircraft. With this latest contract, orders for the APG-79 retrofits of the 133 block II F/A-18s now total 38. See also the related Dec 21/07 entry.
Oct 17/08: An $11.2 million firm-fixed-price, definite-delivery/ definite-quantity modification under a previously awarded delivery order contract (N00383-06-D-001J-0005). The US Naval Inventory Control Point is buying APG-79 radar system spares.
Work will be performed in St. Louis, MO (40%); and El Segundo, CA (60%), and is expected to be complete by May 2011. This contract was not competitively procured.
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Sept 25/08: An $8 million cost plus fixed fee delivery order #0004 under previously awarded contract (N00383-06-D-001J) to repair AN/APG-79 radars. Work will be performed at El Segundo, CA (90%) and St. Louis, MO (10%), and is expected to be complete by September 2009. This contract was not competitively procured by The Naval Inventory Control Point.
July 1/08: The US Navy and its industry partners, Raytheon and Boeing, mark the 100th delivery of the APG-79 Active Electronically Scanned Array (AESA) Radar at a celebration in Forest, MS. NAVAIR release.
March 31/08: A $38.5 million firm-fixed-price, definite-delivery/ definite-quantity contract modification under a previously awarded basic ordering agreement (N00383-06-D-001J, #0004). The firm will deliver new spares to support the AN/APG-79 AESA radar. Work will be performed in El Segundo, CA (90%) and St. Louis, MO (10%), and is expected to be complete by August 2010. This contract was not awarded competitively by the Naval Inventory Control Point.
Dec 21/07: Raytheon Space and Airborne Systems in El Segundo, CA received a $54.8 million firm-fixed-price contract for the procurement of 19 AN/APG-79 active electronically scanned array radars to be retrofitted into F/A-18E/F aircraft Lots 26-29. The radars will replace the APG-73 radars currently installed in the aircraft.
Deliveries were: LOT-26: 48 aircraft, LOT-27: 45 aircraft, LOT-28: 42 aircraft, and LOT-29: 42 aircraft, for a total of 177 aircraft. A total of 42 Low Rate Initial Production (LRIP) APG-79 radars were delivered for installation in the aircraft production line, and the remaining 135 aircraft will be retrofitted. This contract mentioned above is the 1st of 5 projected annual contracts to retrofit those 135 Lot-26 and above F/A-18 E/Fs with the APG-79.
Work will be performed in Forest, MS (43%); Dallas, TX (29%); El Segundo, CA (27%); and Andover, MA (1%) and is expected to be complete in Dec. 2009. This contract was not competitively procured (N00019-08-C-0001).
Oct 17/07: An $11.2 million order against a previously issued basic ordering agreement (N00019-05-G-0026) for the nonrecurring engineering to upgrade 210 AN/APG-79 Active Electronically Scanned Array radar to the B configuration (includes 114 retrofit and 96 production upgrades). All Raytheon would say is that the APG-79 B configuration is “an approved engineering change for a hardware modification.”
Work will be performed in El Segundo, CA (95%) and St. Louis, MO (5%), and is expected to be complete in September 2011.
July 11/07: A $7.6 million firm-fixed-price, definite-delivery/ definite-quantity delivery order (#0002) under previously awarded contract (N00383-06-D-001J) on July 10, 2007, for new spare parts to support the F/A-18 AN/APG-79 (AESA) radar. Work will be performed in El Segundo, CA (9%) and St. Louis, MO (10%), and is expected to be complete by October 2008. This contract was not awarded competitively by the Naval Inventory Control Point.
July 5/07: Boeing received a $90.2 million modification to a previously awarded firm-fixed-price contract (N00019-04-C-0014) for a newly developed, additional capability for the AN/APG-79 Active Electronically Scanned Array radar. Work will be performed in El Segundo, CA (95%) and St. Louis, MO (5%), and is expected to be complete in September 2011
While these exact capabilities were not disclosed, DID’s top bets would be “big SAR” wide angle surface scans that will now be part of the production F-35 Lightning, or limited electronic warfare capabilities.
May 16/07: A $7.4 million modification to a previously awarded firm-fixed-price contract (N00019-04-C-0014) for the redesign of 5 monolithic microwave integrated circuits utilized in the AN/APG-79 AESA radar. Work will be performed in El Segundo, CA (95%) and St. Louis, MO (5%), and is expected to be complete in December 2008. Contract funds in the amount of $6 million will expire at the end of the current fiscal year.
Jan 8/07: Boeing announces delivery of the 11th F/A-18E/F Super Hornet Block II to Naval Air Station (NAS) Oceana, VA. Boeing is delivering AESA-equipped Super Hornet Block II aircraft to 2 squadrons at NAS Oceana: the Black Lions of VFA-213 and the Gladiators of VFA-106. In addition, there are two AESA-equipped Block 2 Super Hornets attached to VFA-122, the Flying Eagles Fleet Replacement Squadron (i.e. training squadron), at NAS Lemoore, CA.
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Oct 27/06: The “Black Lions” of VFA-213 squadron have transitioned from their F-14D Tomcats, and become the first AESA-equipped F/A-18E/F Super Hornet operational squadron to attain “safe for flight” status, which clears it to independently fly and maintain its state-of-the-art Block II aircraft. Source.
Sept 21/06: Raytheon Co. Space and Airborne Systems in El Segundo, CA received an $11 million delivery order against a previously issued basic ordering agreement (N00019-05-G-0008) for system test equipment (STE) for the AN/APG-79 AESA radar for the F/A-18E/F and EA-18G aircraft. The STE will be used to test radar modules returned for repair to determine root cause of failures and to return the radars to the Fleet in a ready for issue status.
Work will be performed in El Segundo, CA and is expected to be complete in September 2009. Contract funds in the amount of $6.4 million will expire at the end of the current fiscal year.
April 18/06: Boeing announces a successful demonstration of the F/A-18E/F Super Hornet Block II’s to provide targeting coordinates to other aircraft using the Raytheon APG-79 Active Electronically Scanned Array (AESA) radar system:
“During the test at the Naval Air Weapons Center at China Lake, Calif., an AESA-equipped F/A-18F created a long-range, high resolution synthetic aperture radar map and designated four closely-spaced stationary targets. The aircraft then data-linked two target designations to non-AESA equipped Super Hornets, which successfully delivered four 2,000-lb. Joint Direct Attack Munitions (JDAM). All four weapons impacted the targets within lethal distance. The targeting Super Hornet then used the AESA to provide highly detailed bomb damage assessments to confirm the hits.”
Dec 5/05: Raytheon states that its a Super Hornet equipped with its APG-79 radar successfully delivered multiple JDAM GPS-guided smart bombs on target, using real-time targeting coordinates derived from a high resolution SAR (synthetic aperture radar) image taken by the radar. The tests were conducted at the U.S. Navy’s China Lake facility. They add that the release of multiple precision-guided weapons from a single radar SAR map is a first, and note integration with other equipment as well:
“To further demonstrate the synergy of the onboard Raytheon sensors, the JDAM test also employed the ATFLIR (Advanced Targeting Forward-Looking Infrared) system to provide imagery of the targeting area. Interfacing seamlessly with the APG-79, ATFLIR recorded the impact of the weapons against two diverse targets, confirming simultaneous weapon delivery while providing post-impact bomb damage information…
The program has also been highly successful during the recent air-to-air live fire demonstrations last month in which an AMRAAM was successfully deployed. This proved that weapons delivery from an AESA equipped F/A-18 can now be executed at ranges not possible before. “In the past, the weapon’s capability exceeded that of the aircraft. The missile could reach the target, but the radar couldn’t see it. Now, with the APG-79 radar, the aircraft’s capability exceeds that of the weapon, and this gives us an enormous advantage when prosecuting a mission,” said Capt. Aaron “Slime” Bowman, U.S. Navy AESA program manager for the F/A-18.”
Oct 31/05: Raytheon discusses the results of multiple live firing tests this month using inert AMRAAM and JDAM weapons. Both AMRAAM (Advanced Medium-Range Air-to-Air Missile) and JDAM (Joint Direct Attack Munition) live fire tests were successful at proving out the radar’s air-to-air and air-to-ground targeting capabilities. How does this work? Raytheon explains:
“The AMRAAM engages long-range targets after launch by incorporating targeting data from the APG-79 AESA. During flight the AMRAAM receives updated tracking/targeting information from the APG-79 AESA radar via data link from the launch aircraft…. The JDAM “Smart Weapon” uses the APG-79 AESA radar to provide precise targeting coordinates. The pilot uses a high resolution SAR (synthetic aperture radar) image to identify the intended target. The target is designated from the image; the target coordinates are passed to the JDAM weapon; the weapon is released and flies under GPS navigation to impact, thus completing the kill chain. Prior to the introduction of the APG-79 radar, it has only been possible for pre-mission planned ground targets to be attacked. Now, with the Active Electronically Scanned Array (AESA) APG-79, real time, time sensitive ground targets can be identified and engaged.”
The APG-79 radar is currently in developmental flight testing and initial operational assessment. The program is expected to transition into OPEVAL (operational evaluation) on schedule in early 2006.
June 28/05: Raytheon Co. announces a $580 million, multi-year subcontract to deliver 190 AN/APG-79 AESA net-centric enabled radar systems for the Boeing Co. over the next 5 years, for installation in production F/A-18 E/F Super Hornet fighter planes. This successfully concluded negotiations for 190 radars from low rate initial production (LRIP) lots 3 & 4, through full rate production lots 1-3.
The first low rate initial production APG-79 AESA radar designed for the F/A-18E/F was delivered to Boeing IDS (Integrated Defense Systems) in January 2005. Following successful installation and testing, Boeing plans to deliver the first AESA-equipped F/A-18F to the U.S. Navy in April 2006. Raytheon release.
June 23/05: a $102.4 million modification to a previously awarded firm-fixed-price contract (N00010-03-C-0054), exercising exercise an option for 22 AN/APG-79 low-rate-initial-production III (LRIP III) Active Electronically Scanned Array (AESA) radar systems for the F/A-18E/F Super Hornet aircraft. Work will be performed in El Segundo, CA (88%); St. Louis, MO (6%) and Marion, VA (6%), and is expected to be complete in December 2007.
April 21/05: Boeing debuts the F/A-18E/F Block II Super Hornet equipped with the APG-79 AESA radar system at a ceremony at Boeing’s St. Louis, MO facilities. The aircraft will be used as part of the AESA radar flight test program prior to entering Operational Evaluation (OPEVAL) in 2006.
The AESA radar, built by the Raytheon Corporation of El Segundo, CA is part of the F/A-18E/F Block II upgrade, which includes integration of advanced mission computers, high speed data network, cockpit controls and displays, environmental control system upgrade and forward fuselage affordability improvements. It works with several existing elements of the weapon system, such as the stores management system, the gun director, and AIM-120 and AIM-9 missiles, to enhance the lethality, survivability and affordability of the F/A-18E/F. The AESA radar and the Block II upgrades are being delivered under 2 multi-year contracts. Boeing press release
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Feb 5/04: A $61.8 million modification to a previously awarded fixed-price-incentive contract (N00019-03-C-0054), exercising an option for 12 AN/APG-79 low-rate initial production II (LRIP II) AESA radar systems for the F/A-18E/F Super Hornet aircraft. Work will be performed in El Segundo, CA (70%); St. Louis, MO (25%); and Marion, VA (5%), and is expected to be complete in September 2006.
Boeing’s release adds that: “Production of the LRIP2 radar is scheduled to begin March 2004, with delivery of the first LRIP2 radar-equipped aircraft scheduled for December 2005. The radars will be installed in selected two-seat “F” model Super Hornets. The radar system currently is undergoing evaluation testing at Naval Air Systems Command, China Lake, Calif.”
Sept 3/03: A $49.5 million fixed-price-incentive contract for 8 AN/APG-79 low-rate-initial-production AESA radar systems for the F/A-18E/F Super Hornet aircraft. Work will be performed in El Segundo, CA (70%); St. Louis, MO (25%); and Marion, VA (5%), and is expected to be complete in September 2006 (N00019-03-C-0054).
Boeing’s release adds that: “Production of the LRIP1 radar could begin as soon as next month, with delivery of the first LRIP1 radar scheduled for early 2005.”
June 30/03: An F/A-18 Super Hornet test aircraft carrying the APG-79 Active Electronically Scanned Array radar system completes several test flights with the radar operating at Naval Air Systems Command China Lake, CA. They are the first test flights with this AESA radar. Boeing release.
Jan 15/03: A $14 million ceiling-priced order against a previously awarded basic ordering agreement (N00019-97-G-0037) to buy Time Critical Parts for 8 low-rate initial production AN/APG-79 AESA radars for the F/A-18E/F Super Hornet. Work will be performed in El Segundo, CA (90%) and St. Louis, MO (10%), and is to be complete in June 2003.
Nov 20/02: Boeing and subcontractor Raytheon roll out integrated APG-79 Active Electronically Scanned Array (AESA) radar in a ceremony at Raytheon facilities in El Segundo, CA. Boeing release | Raytheon release.
Feb 8/01: A $324.5 million cost-plus-fixed-fee, award-fee contract for the design, development, fabrication, integration, installation and test of 5 full and 2 partial AN/APG-79 Active Electronically Scanned Array (AESA) radar engineering development models for the F/A-18E/F Super Hornet aircraft. Work will be performed in St. Louis, MO (59%) and El Segundo, CA (41%), and is expected to be complete by January 2006. This contract was not competitively procured (N00019-01-C-0074).
- Raytheon – AN/APG-79 AESA Radar. See also Raytheon AN/APG-79 Product brochure [PDF]
- Raytheon – Raytheon’s Revolutionary AESA Technology. Includes links to their various AESA radar designs and capabilities, and adds as a list of related press releases at the bottom. Raytheon’s AESA fighter radars fly on the USA’s F/A-18 Super Hornet (APG-79) and F-15 Eagle/ Strike Eagle (APG-63v2-3) fleet.
- Northrop Grumman – AESA Radar: Revolutionary Capabilities For Multiple Missions [PDF format]. Details a number of the radar type’s characteristics that make it special, and offers insights into some of the developments within the AESA field. NGC makes AESA fighter radars for the F-16 Block 60 (APG-80), F-22 (APG-77), and F-35 (APG-81) platforms.
- DID (Dec 18/05) – AESA Comlinks. Dr. Carlo Kopp has already done a fair bit of work in the field, beginning with his PhD thesis in Melbourne in 1999.
- Aviation Week & Space Technology (Dec 11/05) – Talking Radars
- DID (Oct 24/05) – Supersonic SIGINT: Will F-35, F-22 Also Play EW Role?
- Australian Aviation (June 2002) – Active Electronically Steered Arrays: A Maturing Technology
Related Super Hornet Contracts
- DID FOCUS Article – Super Hornet Fighter Family MYP-III: 2010-2013 Contracts
- DID Spotlight Article – The USA’s 2005-2009 Multi-Year Hornet Procurement Contract
- DID FOCUS Article – EA-18G Program: The USA’s Electronic Growler
- DID Spotlight Article – Australia Buying 24 Super Hornets As Interim Gap-Filler to JSF. They will be 2-seat F/A-18F Block II aircraft, with the APG-79.
