The Lockheed P-3 Orion currently serves in the Anti-Submarine Warfare (ASW) and maritime patrol roles for various countries around the world including the United States where its chief customer is the United States Navy (USN). Some 757 examples of the type have been produced since series introduction began in 1962 with Lockheed accounting for 650 of this total and Kawasaki of Japan adding another 107 units (local, licensed). The P-3 was developed from Lockheed's L-188 "Electra" passenger hauler and, itself, has been the origin for other designs including the AP-3C "Orion", the CP-140 "Aurora", the EP-3 and the WP-3D "Orion". As of this writing (2017), the P-3 maintains an active presence in the USN inventory though it has been officially superseded on paper by the P-8A "Poseidon" detailed elsewhere on this site.
Rather amazingly, the P-3 series has proven itself a fleet workhorse, amassing over fifty years of consistent, reliable over-water service. Its operators span the globe and run from Argentina and Australia to Taiwan and Thailand. It is certainly one of the more important aircraft in the skies today.
The Orion series was born from a 1957 USN requirement calling for an all-modern, land-based maritime patroller to succeed its aging line of Lockheed P2V/SP-2 "Neptune" aircraft in same role. As this was during the Cold War period, the new aircraft would be charged with searching and tracking Soviet ballistic missile and general attack submarines threatening U.S. interests worldwide. To expedite the development process, Lockheed elected to modify its existing Electra airliner and this work commenced in April of 1958. A prototype went airborne for the first time on November 25th, 1959 and the design was selected ahead of others by the USN with service entry had in August of 1962.
The basic aircraft shared some external similarities to the Electra passenger hauler. A tubular shape made up its fuselage which carried low-set, straight monoplane wings, a single-finned tail unit and stepped cockpit flight deck. At the rear was added a boom assembly containing a Magnetic Anomaly Detector (MAD) and the belly incorporated a weapons bay. Powerful radar was also carried aboard and various onboard stations allowed multiple mission specialists to make up the crew.
Supported weapons (held in an internal bay and across ten external hardpoints) include Air-to-Surface (ASM) missiles like Maverick, the AGM-84 Harpoon / SLAM-ER Anti-Ship Missile (ASM), Mk 46, Mk 50 and Mk 54 series torpedoes and unguided rockets. Additionally, the aircraft can dispense naval mines over target areas and drop depth charges on reported submarine positions as needed.
Variants of the P-3 Orion have been many and these followed the various major production models, either adopted or proposed, by Lockheed. The initial form was the P-3A which grew to include several subvariants. Similarly the P-3B held its own stock of subvariants which numbered four and these mainly introduced more powerful engines. The definitive mark is the P-3C which counts six total major subvariants as well as a slew of modified and updated sub-models. These appeared with more powerful radar fits, updated MAD equipment and modernized systems.
The P-3C carries a crew of eleven and has a fuselage length of 116.9 feet, a wingspan of 99.7 feet and a height of 38.7 feet. Empty weight is 77,200lb against an MTOW of 142,000lb. Power is from 4 x Allison T56-A-14 turboprop engines developing 4,600 horsepower each and these drive four-bladed (Hamilton Standard) propeller units. Maximum speed is 465 miles per hour with a range out to 4,830 nautical miles (ferry) and a service ceiling reaching 28,300 feet. Rate-of-climb is 3,140 feet-per-minute.
The UP-3D became an ELectronics INTelligence (ELINT) airborne trainer for the Japanese Maritime Self-Defense FOrce (JMSDF). The RP-3D was a one-off and used in testing of MAD equipment. The WP-3D is a P-3 associated with NOAA and used in weather tracking / data collection. The EP-3E "Aries" and "Aries II" marks serve as ELINT aircraft. The EP-3E is a SIGnals INTelligence (SIGINT) platform with L-3 Communications equipment. The NP-3E has been used as a testbed for various programs.
The P-3F were six Orions delivered to the then-pro-Western government of Iran prior to the Fall of the Shah in the 1970s. The P-3G was used to mark the proposed P-3 successor by Lockheed which became the P-7A (not adopted). Similarly, the "Orion 21" was another intended successor but was bested by the Boeing proposal which has since produced the P-8 Poseidon. The P-3H designator was a proposed P-3C model upgrade which never happened. The EP-3J model numbers two P-3A platforms modified as enemy Electronic Warfare (EW) platforms for training.
New Zealand manages the P-3K and P-3K2 models and Norway the P-3M and P-3N. Portugal uses the P-3P which are ex-Australian examples. The Thai Navy has the P-3T and VP-3T marks. The Australians knew the aircraft as the P-3W and other Aussie forms became the AP-3C and TAP-3C. South Korea has used the P-3CK.
P-3AEWC signifies some eight P-3B models converted for the Airborne Early Warning & Control role.
Canada operates P-3 Orions as the CP-140 Aurora and CP-140A Arcturus. The latter lacks the ASW equipment and is used primarily for training.
Lockheed bills the P-3 as the "World Standard in Maritime Patrol Aircraft" and for good reason - nearly twenty military operators keep it in active inventory. The P-3 has seen action since the Cuban Missile Crisis of 1962 and throughout the latter half of the Vietnam War (1955-1975). Additional combat service has been had in the 1991 Iraq War, Operation Enduring Freedom (2001), Operation Iraqi Freedom (2003), the Libyan Civil War (2011) and in ongoing anti-piracy actions over Somali waters.
Beyond the arrival of the P-8 model, there is little sign of the P-3 series will be retired any time soon. A Mid-Life Upgrade (MLU) by Lockheed have ensured that the P-3 remains a viable maritime participant for the near future.