In the United States Navy, they are responsible for manning the weapon systems of a fighter. (In the U.S. Air Force and Marine Corps, "WSO" also refers to the aft crew member in the F-15E Strike Eagle, B-1 Lancer and F/A-18D Hornet.) The WSO integrates with the pilot to collectively achieve and maintain crew efficiency, situational awareness and mission effectiveness. In the U.S. Air Force fighter aircraft such as the F-15E Strike Eagle, the WSO can pilot the aircraft when required although this is typically during non-tactical portions of the mission (e.g., returning to base). When designated mission commander (MC), the WSO is also responsible for all phases of the assigned mission.
In the British Royal Air Force, a WSO (formerly navigator) is a commissioned officer that operates aircraft mission systems on the Tornado GR4 amongst other platforms. Non-Commissioned aircrew can serve as a WSOp (Weapon Systems Operator), an umbrella term for the various specialist aircrew responsible for assisting the pilot in operating the mission systems of the aircraft (e.g. linguists, loadmasters, crewman).
WSO mission duties in fighter aircraft were historically rigid because of the displays and controls in the front and aft seats of fighter cockpits. However modern fighter cockpits using programmable multi-function displays allow assigned roles to be more flexible than previous generation aircraft such as the F-4 Phantom II, A-6 Intruder, or F-14 Tomcat. In the latest fighters either aircrew can be responsible for detecting, targeting and engaging air-to-air targets or ground targets, performing communications, operating data-link or defensive systems based on the tactical situation. This provides the flexibility for pilot and WSO roles to be customized based on experience, expertise, workload, tactics, and weapons being employed. The pilot remains responsible for flying the aircraft in tactical situations. WSOs assigned to bomber aircraft typically have more rigidly defined roles.
Currently all USN WSOs are trained at various locations in the country but all SNFOs (Student Naval Flight Officers) start training at NAS Pensacola, Florida. Training begins with Introductory Flight Screening where the WSO flies a Cessna 172 to show he/she is competent enough in aviation to continue the rigorous training ahead. Then the SNFO starts the U.S. Navy indoctrination course called Aviation Preflight Indoctrination (API). After six weeks of ground school and basic water survival training during API, SWSOs (Student WSOs) check in to the Training Squadron, VT-10 Wildcats for Primary and Intermediate training.
Training begins with several weeks of ground school followed by remnants of the "super-fo" program from the U.S. Navy where the SWSO takes front seat of the new T-6 Texan II for six "contact" flights where the student will become familiar with the T-6 and general aviation. The SWSO is treated like a pilot training student for these six flights. After Contacts, the SWSO goes back to academics to learn instrument flying rules. Primary ends with a final instrument checkride. After primary the SWSO is compared to his shipmates and selected for tail hook (Aircraft carrier based platforms that have WSOs which are; the E-2, E/A-6B, E/A-18G or F/A-18F).
Intermediate picks up where Primary ends for USAF SWSOs. After the instrument phase of training, students move to visual navigation (VNAV) "low levels" at 2000'AGL, and finish in the T-6 with a final training block called "forms" (formation flying). Forms consist of four flights of learning the basics of close in formation flying. After forms, SWSOs head back to ground school to learn an entirely new aircraft, the USN T-39 Sabreliner. The T-39 is used as an intermediate instrument and low-level trainer for SWSOs, where they receive a total of eight flights. Students are required to learn the aircraft in a two-week ground school period before they go flight side. In contrast, T-6 ground school is four weeks. Training ends at either VT-10 or VT-4 with the "i-grad" ceremony and top graduate award.
VT-86 is where all the training comes together to culminate in the SWSO receiving his or her wings of gold. In the T-39, a USN twin-engine jet trainer, SWSOs learn advanced instrument flying, radar navigation (consisting of navigating using an A/G radar from early F-16s), and composite visual/radar navigation. Training takes place on both VR and IR routes that criss-cross the south east United States. After A/G training, track selection takes place. SWSOs select either the F/A-18 Superhornet, or the E/A-18 Growler. The final three months of some of the hardest training at Pensacola will leave the SWSO F/A-18 selectee with their wings of gold. Air force WSO's no longer train at VT-86.
Following the winging ceremony, WSOs complete several training courses to prepare them for the combat Air Force.
Parachuting water survival
All USAF aviators with parachutes on the aircraft attend this three-day course at NAS Pensacola, Florida. During the course, WSOs learn the basics of surviving an aircraft ejection over water, obtaining food and drinkable water when stranded at sea, combat evasion at sea, and how to be successfully rescued by boat or helicopter.
This one-day course located at Brooks City-Base, San Antonio, Texas, tests WSOs selected for the F-15E in their ability to withstand the g-forces routinely experienced by fighter aircrew.
The Survival, Evasion, Resistance and Escape (SERE) training course trains all USAF aircrew basic survival skills, combat evasion, and techniques to resist exploitation if captured. WSOs also learn how to survive an aircraft ejection over land. The three-week course is taught at Fairchild Air Force Base, Washington and the surrounding areas.
WSOs selected for the F-15E learn basic fighter maneuvers (BFM) and surface attack in the T-38C at Introduction to Fighter Fundamentals (IFF). WSOs complete this training at either the 435th Fighter Training Squadron at Randolph Air Force Base, Texas or the 49th Fighter Training Squadron at Columbus Air Force Base, Mississippi. WSOs also learn about the culture of being a young aircrew member in a USAF fighter squadron. The course lasts approximately eight weeks.
SWSOs selected for the B-1B, EA-6B Prowler, B-52H, and some F-15E selectees will become electronic warfare officers (EWOs) by attending this 12-week training program at the 563rd Flying Training Squadron at Randolph Air Force Base, Texas. Students learn the basics of radar theory, electronic attack, and electronic defense.