Vertical Lift

Fleet Readiness Center Southwest Vertical Lift Aircraft

H-1 Helicopter
AH-1Z Viper, UH-1Y Venom

Since the mid-1950s, various models of the H-1 helicopter airframe have served the Navy and Marine Corps.

The Marines developed an upgrade to the airframe in 1996 to replace its AH-1W Super Cobra attack helicopter with the AH-1Z Viper, and the UH-1N Twin Huey utility helicopter with the UH-1Y Venom.

Technologically superior to their predecessors, the Viper and Venom are composite four-bladed, twin-engine helicopters. Production of the UH-1Y began in 2009, and the AH-1Z one year later.

Both aircraft are maintained under the Integrated Maintenance Program (IMP), and because they share many common components, their maintenance procedures are very similar.

The IMP is designed to keep the aircraft mission-ready by targeting the integrity of the airframe via two assessment events --- Planned Maintenance Interval-one (PMI-1) and PMI-2.

Prior to PMI-1, the aircraft’s squadrons remove the blades, and the command’s artisans remove the aircraft’s intermediate and tail gear boxes, panels, engine and transmission for evaluation.

The disassembled aircraft are assessed and repaired within the scope of the PMI specification, which includes a thorough examination of the tail boom. The aircraft’s oil, fuel and hydraulic systems hoses are also changed during this interval.

In addition, for the AH-1Z, its stub wings are removed and the connecting points, bushings and stub wing lugs examined.

Damages or areas of concern outside of the IMP scope of specifications are reported to the squadron, and are typically repaired as an in-service repair (ISR).

The PMI-2 cycle entails similar evaluations to the PMI-1, but the aircraft are also stripped via particle media blast (PMB) and painted.

Fleet Readiness Center Southwest UH-1Y Venom helicopter

U.S. Marines fast rope out of a UH-1Y Venom helicopter.


Fleet Readiness Center Southwest AH-1Z Viper helicopter

An AH-1Z Viper taxis down the flight line aboard MCAS Camp Pendleton, California.

H-53 Helicopter
CH-53E Super Stallion

For more than 30 years, the CH-53E Super Stallion helicopter has remained a staple in the logistics toolbox of Navy and Marine Corps operations.

The largest helicopter ever built by the Defense Department, the CH-53 can transport up to 16 tons of cargo and is often assigned to amphibious class ships.

FRCSW provides MRO events to those CH-53Es assigned to Marine Corps Air Station (MCAS) Miramar.

The maintenance schedule of the Super Stallion is based upon a 54-month cycle of the Integrated Maintenance Program (IMP).

The IMP targets structural repairs to the fuselage and includes replacing the skin, transition bulkhead, cockpit floorboard, any KAPTON electrical wiring upgrades and corrosion repair throughout the aircraft.

After induction, FRCSW artisans disassemble the aircraft and begin the IMP inspection specifications.

The program operates in two buildings: one where fiberglass and component work is done and the other where the remaining airframe work is completed.

The IMP workload standard requires about 16,000 manhours per aircraft.

Unlike the IMPs of other airframes serviced by FRCSW, the Super Stallion program is a combination of organizational level (O-level), or work handled by the Marine Corps squadrons, and depot-level work.

In the event a repair exceeds O-level capability, the Marines have the option to transfer the repair to the depot as an In-service Repair (ISR).

Fleet Readiness Center Southwest CH-53E Super Stallion

A CH-53E Super Stallion helicopter landing on the flight deck of the amphibious assault ship USS Bonhomme Richard (LHD 6).


H-60 Helicopter
MH-60R, MH-60S Sea Hawk

To improve its H-60 MRO capacity, FRCSW opened Building 325 in 2016, an 110,627 square-foot facility solely devoted to the maintenance and repair of the Sea Hawk.

The command’s H-60 MRO program applies the Integrated Maintenance Program (IMP) to assess and ensure the structural integrity of the MH-R and MH-S models of the airframe. Both models support aircraft carrier battle groups. Under the IMP, aircraft undergo a Planned Maintenance Interval-One or Two (PMI-1 or PMI-2) cycle.

PMI is a cell-based structure, with each cell dedicated to a specific function that includes induction, disassembly, evaluation, repair, modification, assembly, test and finally a “sell” or return to the fleet.

The inspection targets six sections or zones of the aircraft. Not all zones are covered during both PMI cycles. During PMI-1 the cockpit, cargo area, fuel system, tail pylon and tail rotor are examined. In PMI-2, artisans revisit the cockpit and cargo area, and assess the tail cone and the upper deck of the aircraft and main rotor.

The aircraft is also stripped and painted.

Although out of the scope of the IMP, FRCSW handles in-service repair (ISR) work on major components under a separate work order. Modifications and upgrades, like avionics, are also sizable portions of workload

Six years ago, the command purchased a Laser Alignment Fixture to assist in the repair of crash damaged H-60 aircraft.

The only one of its kind in the Navy today, the system is applicable to all H-60 variants and enables the alignment of the aircrafts beams, drive shaft and engine mount.

Use of the fixture expanded in FY 2018 when Fleet Support Team engineers applied it during a study to establish baseline data to extend the life of the airframe.

Fleet Readiness Center Southwest MH-60S Sea Hawk helicopter

An MH-60S Sea Hawk helicopter fires an AGM-114B Hellfire missile during a live-fire exercise.


Fleet Readiness Center Southwest HH-60G Pave Hawk helicopter

An FRCSW sheet metal mechanic installs a bracket on an Air Force HH-60G Pave Hawk helicopter.

AV-8 Aircraft
AV-8B Harrier II

For more than 15 years FRCSW has provided MRO services to the vertical/short takeoff and landing (VSTOL) AV-8B Harrier jet.

Designed in the late 1970s, the single-engine aircraft entered service with the Marines Corps in the mid-1980s and is used in light attack and reconnaissance missions.

Operating from its sites at Marine Corps Air Station Yuma, AZ, and Naval Air Weapons Station China Lake, CA, FRCSW performs a Planned Maintenance Interval-D (PMI-D) on the airframe.

PMI-D is scheduled approximately two years in advance in conjunction with the AV-8B Weapon Systems Program Office (PMA-257) and the AV-8B Fleet Support Team (FST).

Prior to induction, the engine is removed and the wing assembly is disassembled. The aircraft’s squadron removes the ejection seat and explosive cartridge actuated devices.

During PMI-D, artisans inspect and repair damaged or worn sections of the airframe and its components. Most of the aircraft have various airframe and mission system modifications completed simultaneously with the PMI event.

Repairs outside of the PMI are completed separately as in-service repairs (ISR), or are separate work orders. ISRs average about 7,000 hours annually on the airframe.

Fleet Readiness Center Southwest AV-8B Harrier II

An AV-8B Harrier II prepares to land aboard the amphibious assault ship USS Boxer (LHD 4).