Orion’s Final Hunts

Rick Burgess reviews the current P-3 Orion fleet of the US Navy


A P-3C Orion assigned to Patrol Squadron 46 (VP-46) at Naval Air Station Whidbey Island prior to a training mission.
Mass Communication Specialist 3rd Class Alex Cole/US Navy

Transition to the P-8A Poseidon maritime surveillance aircraft in the US Navy is more than halfway complete. First deliveries of production standard MQ-4C Triton unmanned aerial systems are scheduled for this year. These new systems get many of the headlines and it’s easy to forget about legacy platforms like the P-3C Orion maritime patroller and the EP-3E Aries II electronic reconnaissance version. Both types will soldier on for a few more years until their replacement is complete. The US Navy has a plan for each type. Its fleet of now ancient Lockheed P-3C Orion aircraft will be phased out by 2020, followed in 2021 by the retirement of the EP-3E Aries II. Both types are being replaced with a family of systems which includes P-8, MQ-4C Triton and TacMobile working together.

Powered by four Allison T56 turboprop engines, the P-3 Orion entered operational service in August 1962. Only two months later, the type was engaged in surveillance during the Cuban missile crisis. Today, all US Navy patrol squadrons equipped with the Orion fly the P-3C model which first entered operational service in 1969, remained in production (with Kawasaki Heavy Industries, Japan) until 1996 and has been modified with a succession of upgrades over the decades.

During the Cold War, the P-3 primarily conducted anti-submarine warfare (ASW) surveillance of Soviet submarines and ships. During the Vietnam War, the Orion provided surveillance to support interdiction of North Vietnamese shipping. Its overland surveillance capabilities were deployed during Operation Desert Storm in 1991.

The P-3 Orion has a significant strike capability with Stand-off Land-Attack Missiles (SLAMs) which was used against Serbia in 1999 and al-Qaeda forces in Afghanistan in 2001.

During the recent wars in Afghanistan and Iraq, P-3Cs supported coalition forces, including special operations forces, with overland surveillance. In 2011, P-3Cs countered Libyan shipping with AGM-65 Maverick missiles.

Active-duty P-3C patrol squadrons (VP) based at Naval Air Station Jacksonville, Florida, transitioned to the P-8A in the following order: VP-16, VP-5, VP-45, VP-8, VP-10 and VP-26.

Of the three VP squadrons based at Marine Corps Base Kaneohe Bay, Hawaii, VP-4 has moved to Naval Air Station Whidbey Island, Washington, and completed transition in May. A second unit, VP-47 is following VP-4; and VP-9, on deployment until October, will follow VP-47 to Whidbey Island upon return. Three other P-3C squadrons based at Whidbey, VP-40, VP-1, and VP-46, will follow in that order. The last, VP-46, was the first west coast patrol squadron to receive the P-3A, in 1963.

Patrol squadrons still flying the Orion operate the most recent version dubbed the P-3C Anti-surface Improvement Program (AIP) with C4ASW (Command, Control, Computers, Communication for Anti-Submarine Warfare) upgrades. Exceptions are some P-3C Update III/IIIR aircraft used for pilot training and Block Modification Upgrade (BMUP) versions equipped with the APS-149 Littoral Radar Surveillance System (LSRS).

Current configurations

Baseline configuration of the current Orion fleet is the P-3C Update III, but most have received further upgrades.

The P-3C AIP includes enhancements in sensors, communications, displays and controls, survivability, vulnerability and weapons capability. Major sensor systems included the APS-137B(V)5 synthetic aperture radar, USQ-78B acoustic processing system, ASQ-81 magnetic anomaly detection system, ALR-95 electronic support measures system and an ASX-4 electro-optical/infrared (EO/IR) turret housing the Advanced Imaging Multispectral System (AIMS). The Anti-Surface Improvement Program also incorporated over-the-horizon targeting upgrades fathered in the Outlaw Hunter modifications used in Operation Desert Storm, which evolved into a system known as OASIS or Over-the-horizon Airborne Sensor Information System. OASIS III increments formed the core of the AIP upgrades which were installed in 72 P-3Cs between 1996 and 2007. Patrol Squadron 9 (VP-9) was the first unit to deploy with the AIP-configured P-3Cs in 1998.

Raytheon’s APS-137(V)5, an inverse synthetic aperture radar (ISAR) upgraded with synthetic aperture radar (SAR) and ground and maritime moving target indicator modes (GMTI and MMTI), capture highresolution imagery of targets that even enable identification of specific vessel types. AIP-configured Orion aircraft are equipped with the ALR-95 electronic support measures system, the latest version of which is equipped with the Automatic Identification System (AIS), which can interrogate AIS systems — those required on ships with a 300-ton (272-tonne) or more displacement — for the ship’s identity, course, speed and other information. According to open source data, the ALR-95 can discriminate between emitters of the same type. AIP-configured aircraft were also armed with the AGM-84E Harpoon Standoff Land-Attack Missile, the aircraft’s first land-attack weapon. Patrol Squadron 10 (VP-10) fired SLAMs against Serbian targets in 1999, VP-9 fired the same type of missile against al-Qaeda targets in Afghanistan in October 2001 following 9/11.

This P-3C Orion BMUP is fitted with an APS-149 Littoral Surveillance Radar System.
Mark Ayton

P-8A Poseidon, the US Navy’s replacement aircraft for the P-3C, can be armed with torpedoes and anti-ship missiles, but does not have the P-3C’s land-attack capability provided by AGM-84 SLAM-Extended Range missiles. The Navy, however, does not seem concerned about the P-8’s lack of a landattack capability. When asked, Chief of Staff for Commander Patrol Reconnaissance Group, Captain Chris Ramsden did not directly address the lack of a land-attack capability in the P-8A but said: “The P-8A Poseidon is, by design, a maritime patrol aircraft and is appropriately equipped and armed to conduct its maritime missions.”

P-3Cs became heavily involved in overland surveillance in Afghanistan and Iraq, with the aircraft’s most useful system being the ASX-4 turret capturing high-resolution, long-range, EO/IR imagery for the crew and ground forces. The system proved equally useful in identifying vessels at sea during maritime security operations. Aircraft also carried observers from ground units or special operations forces who were able to use target information captured by the aircraft’s sensors to direct combat on the ground; the aircraft can also downlink video to commanders on the ground.

P-3Cs have been used for surveillance of areas along the Afghan-Pakistan border, and have provided surveillance of the perimeters of US bases in Afghanistan.

Final major upgrade

In December 2006, the US Navy started the C4ASW, the last major upgrade programme for the P-3C.

C4ASW incorporates Link 16, which provides enhanced situational awareness and full interoperability with US Navy battle groups, other military services and NATO forces, and International Maritime Satellite (INMARSAT) broadband connectivity into AIP P-3Cs. INMARSAT provides encrypted broadband services for the fleet and a full range of communications including messages, email, web access and full motion video. The C4ASW programme reached initial operational capability with Patrol Squadron 5 (VP-5) based at Naval Air Station Jacksonville, Florida on September 27, 2011, and has been installed in 52 P-3C AIP aircraft.

The P-3C entered service in 1969 with Link 11, a data exchange network that operates in the high frequency and ultra-high frequency (UHF) range. For decades, the P-3C could exchange surveillance and contact data with warships such as aircraft carriers, cruisers, destroyers, and with E-2 and later S-3 aircraft. But with Link 16, a UHF line-of-sight net, the Orion is able to communicate with a wider array of platforms, including warships, the F/A-18 strike fighter, the EA-18G electronic attack aircraft, and MH-60R and MH-60S helicopters, greatly increasing the tactical flexibility and value of the P-3C in the networked battle space.

The P-3C’s first satellite communications were just voice-capable but the AIP upgrade added imagery exchange and INMARSAT provides the crew the ability to chat silently via text.

The main hardware additions with the C4ASW modification were the Advanced Tactical Airborne System, Multifunctional Information Distribution System Low Volume Terminal, HSD-400 high-speed data and voice terminal, and the AMT-50 antenna. The AMT-50 is the most obvious feature, being mounted above and behind the cockpit cabin in a distinctive small canoe fairing.

Two P-3C Orion maritime patrol aircraft hold short of runway 31 at Naval Air Station Whidbey Island. The far aircraft has a full colour tail badge for Patrol Squadron 40 (VP-40) ‘Fighting Merlins’.
Mark Ayton
EP-3E Aries III, BuNo 156517 is one of 12 operated by Fleet Air Reconnaissance Squadron 1 (VQ-1) ‘World Watchers’ seen at Elmendorf Air Force Base, Alaska during Exercise Northern Edge 2017.
Mark Ayton

The US Navy has also kept the P-3C AIP’s acoustic sensor signal processing system up to date by integrating the Acoustic Processor Technology Refresh. This upgrade includes the Multistatic Active Coherent capability, using passive sonobuoys with expendable sound sources to actively track quiet submarines. All analogue acoustic data recorders in the fleet have been replaced with digital recorders, and the outdated analogue sonobuoy receivers have been replaced as well.

In order to comply with Federal Aviation Administration airspace regulations, the P-3C fleet has been modified under the Communications, Navigation and Surveillance/Air Traffic Management programme. Orions have been updated with a new communications suite, the Protected Instrument Landing System, Identification Friend-or-Foe Mode S, Traffic Collision Avoidance System and the required navigation performance enhancements including GPS and Automatic Dependent Surveillance Broadcast capability.

AIP-configured aircraft were supplemented by 25 P-3Cs converted from Update II, II.5 and III versions under the BMUP, bringing Update III functionalities provided by more modern avionics that replaced obsolete technology. Each of the 25 aircraft converted to BMUP standard is equipped with the APS-137 radar and the L-3 Wescam ASX-6 Multi-Mode Imaging System (MMIS), a smaller cousin of the ASX-4. The aircraft’s ALR-66 electronic support measures system has been replaced by the ALR-95. Both AIP and BMUP versions are equipped with the USQ-78B acoustic processor and display system for antisubmarine warfare.

Littoral radar surveillance system

Sixteen, upped later to 19, BMUP aircraft were equipped to carry the APS-149 LSRS housed in a large canoe-shaped pod suspended along the ventral centreline of the fuselage. Similar to the US Air Force’s E-8C Joint Surveillance and Targeting Attack Radar (JSTARS), the LSRS is a solid-state, wide-aperture, active electronically-scanned radar that provides stand-off synthetic aperture radar imagery and has a ground moving target indicator (GMTI) mode, with an MMTI (maritime moving target indicator) and ISAR (inverse SAR) capability being introduced. The LSRS can detect and track targets at long standoff ranges and provide targeting-quality track data via Link 16 for precision-guided weapons. Seven such systems, introduced in 2006, were built. In recent years, three were normally available in Southwest Asia for use by P-3 squadrons.

The APS-149 is a factor in slowing somewhat the retirement of the P-3C. The US Navy is developing a successor sensor, the APS-154 Advanced Aerial Sensor (AAS), for the P-8A. The AAS is also a solid-state, wide-aperture, active electronically scanned array radar housed in a long pod under the fuselage. The sensor is designed to provide intelligence, surveillance, reconnaissance and targeting at standoff ranges. Flight tests on P-8A test aircraft began in April 2014.

In a letter published in the first quarter 2017 issue of Planeside, the Maritime Patrol Association’s newsletter, Commander, Patrol Reconnaissance Group, Rear Admiral Kyle Kozad said the US Navy plans to assign its two reserve P-3C squadrons, VP-62 and VP-69, to operate the LSRS as the Orion fleet shrinks, and until the AAS reaches operational status on the P-8A.

Currently, the two reserve squadrons are not scheduled to transition to the P-8A. Instead, their reserve personnel will support Unmanned Patrol Squadrons 19 (VPU-19) and 11 (VPU-11) as they eventually transition aircrew to operate the MQ-4C Triton, Ramsden said.

Special projects

The Navy’s sole remaining special projects patrol squadron, VPU-2, which also operates several P-3Cs as special projects aircraft (SPA) from Marine Corps Base Kaneohe Bay is slated for shutdown without direct replacement.

Naval Air Systems Command’s PMA- 290 Maritime Patrol Reconnaissance Aircraft programme manager Captain Tony Rossi said: “SPA is currently scheduled to disestablish in 2020.”

A secretive unit, known as the Bureau of Personnel Sea Duty Component, operates a small number of extensively modified P-3Cs from Love Field in Dallas, Texas, and is slowly switching its P-3Cs for P-8As. The P-3Cs assigned to the unit, feature a large canoe pod underneath the aircraft, similar in appearance to the LSRS pod, but the Navy has never confirmed a relationship between the two programmes.

Some Orions may hang around longer in fleet support roles. “Currently, there are plans to retain some NP-3Cs and P-3Cs for test and range support and scientific development”, Rossi said. NP- 3Cs and P-3Cs are flown by Air Test and Evaluation Squadrons 20 and 30 (VX-20 and VX-30), and by Scientific Development Squadron 1 (VXS-1, formerly the Naval Research Laboratory Flight Support Detachment). Some of these NP-3Cs were re-designated from NP-3Ds, themselves re-designated in 1994 variously from EP-3A, EP-3B and RP-3D versions. One is equipped with the Extended Area Telemetry System (EATS), modified with a large billboard antenna forward of, and attached to, the vertical stabiliser. Another has an APS-125 radome designed for the E-2C Hawkeye mounted above the fuselage. These aircraft provide a variety of range control and telemetry services for the Pacific Missile Test Range off Point Mugu, California.

VX-1, the Navy’s air anti-submarine warfare operational test squadron, transferred its last Orion last year after continuous operation of the Orion since 1962.

Mark Ayton

Capt Rossi said: “The P-3C faces typical challenges of obsolescence and material condition associated with its age. However, the supply system and intermediate and depot level maintenance is poised to keep the fleet at required readiness levels until retirement. The last P-3 depot level overhaul is scheduled for [fiscal] 2019. P-3Cs continue to be upgraded as necessary to maintain safety of flight and meet emergent operational demands.”

As of February, there were 70 P-3Cs remaining in the Navy’s inventory.


Fleet Air Reconnaissance Squadron 1 (VQ-1), based at Naval Air Station Whidbey Island in Washington, is the last remnant of a community that has collected signals intelligence (SIGINT) and provided early warning since the 1950s. VQ-1, having grown from the absorption of VQ-2, operates 12 EP-3E versions of the Orion, with large crews comprising evaluators, intercept operators and linguists who deploy worldwide, often in response to tasking from national-level authorities. Colloquially, EP-3E Aries III aircraft are referred to as Q-birds, a term derived from the VQ squadron designation.

EP-3E crews fuse SIGINT and off-board information and disseminates the data for direct threat warning, information dominance, battlespace situational awareness, suppression of enemy air defences, destruction of enemy air-defence, anti-air warfare and ASW applications, according to the programme office.

During the early 1990s, the Conversionin- Lieu-of-Procurement programme converted 12 P-3Cs to an EP-3E Airborne Reconnaissance Integrated Electronic System II (Aries II) configuration, using in part mission systems transferred from two EP-3B and 10 older EP-3E Aries I aircraft. Aries II entered service in 1997. The Navy modified four more P-3Cs to EP-3Es in the 2000s to sustain 12 operational aircraft in the fleet at all times. One of the EP-3Es was rebuilt after it survived a mid-air collision on April 1, 2001 with a Peoples Liberation Army Air Force J-8 fighter.

The EP-3E also has gone through upgrades to increase its capabilities. In 2003, the PMA-290 program office began the Joint Airborne SIGINT Architecture Modernization Common Configuration (JCC) upgrade to incrementally improve SIGINT sensor system capabilities of the EP-3E.

P-3C AIP BuNo 158215 is assigned to Fleet Air Reconnaissance Squadron 1 (VQ-1) ‘World Watchers’. The aircraft is shown at the start of its take-off run at its home station, Naval Air Station Whidbey Island.
Mark Ayton

A PMA-290 official said: “JCC upgrades provided the Navy with an automated electronic surveillance measures capability, airborne ForceNET classified network connectivity, precision direction finding, low-band multiplatform geo-location communications collection, recording and information operations capabilities.”

The EP-3E JCC and Task Force Intelligence, Surveillance and Reconnaissance (TF-ISR) modifications included hardware and software upgrades that aligned the EP-3 with the Navy’s cryptologic architecture and bridged the gap between the present capabilities and future manned/unmanned reconnaissance aircraft and integrated Link 16 mission management capabilities.

The Sensor System Improvement Program (SSIP) upgraded the type’s communication, collection and dataautomation capabilities in January 2004.

According to PMA-290, in 2007, the EP-3E programme implemented an electro-optical/infrared (EO/IR) system and ForceNET upgrades to meet emerging TF-ISR requirements. This effort included installation of an EO/IR turret, improved international maritime satellite connectivity, additional special signals boxes and lineof- sight wide-band data links for full-motion video. Because of obsolescence, the EP-3E program also began to upgrade electronic surveillance measures in 2016.

The Navy is keeping the EP-3E modernised until the end of its service life. Replacing capabilities resident in the EP-3E and its crews will be no small chore, but the Navy seems confident it will succeed, although it declines to elaborate on the details of the transition. Capt Rossi said the Navy will transition many of the EP-3 capabilities to the MQ-4C Triton UAS.

Final plans

“The Maritime Patrol and Reconnaissance Force is currently transitioning from legacy platforms to a new family of systems comprising P-8A Poseidon and MQ- 4C Triton supported on the ground by TacMobile. Maritime capabilities resident in legacy platforms will, for the most part, be repopulated in the Family of Systems”, said Ramsden.

TacMobile is the name of the program that provides three command and control systems — the tactical operations centre, the mobile tactical operations centre and the joint mobile ashore support terminal — that support maritime patrol operations.

With aircraft retirements planned, the US Navy has determined when it will stop training new crews for the P-3 and EP-3 aircraft. According to Ramsden, the Fleet Replacement Squadron, VP-30, will cease P-3C aircrew replacement training in 2018 and EP-3 aircrew training in 2019. Discussing the P-3 to P-8 transition, Ramsden said: “P-3C combat aircrews are adapting very well to the new jet. With over half of the VP squadrons complete with P-8A transition, the performance of aircrews on station has been outstanding. The operational and tactical experience of legacy aircrew is very effective in fighting the state-of-the-art Poseidon.”

A P-3C Orion undergoing preflight checks at Naval Air Station North Island prior to a mission in support of a Composite Training Unit Exercise for USS.
Carl Vinson Petty Officer 3rd Class Alexander Cole/US Navy