24-Sep-2020 Source: US Marine Corps
The Navy’s MH-60S Seahawk multi-mission helicopter is ready for a communications upgrade, and engineers with the H-60 Fleet Support Team at Naval Air Systems Command’s In-Service Support Center at Fleet Readiness Center East have developed an innovative solution to support that effort.
The fleet’s inventory of more than 200 MH-60S Block 3 aircraft is slated to receive new Full Motion Video (FMV) systems, which will expand the aircraft’s operational capabilities. A team of structural and avionics engineers with the H-60 FST at FRCE developed prototypes of the equipment that will secure the modification to the aircraft, including two 3D-printed antenna mounts developed in conjunction with the Additive Manufacturing team at NAVAIR headquarters in Patuxent River, Maryland.
“The modification consists of three antennas, and equipment rack and a series of electronics mounted to the rack,” said Tommy Stokes, a structures engineer on the H-60 FST. “The 3D-printed omnidirectional antenna mounts are getting a lot of attention, because it’s a relatively new technology.”
While the third antenna mount and equipment rack will be manufactured through more traditional methods, the two remaining antennas provided the development team with an opportunity to think outside of the box and explore additive manufacturing options.
“The relatively light weight of the antennas being mounted to the 3D-printed mounts allowed for that manufacturing process, as the mounts will not experience significant structural loads or stress,” Stokes said.
The unconventional production method also provided the quickest and most cost-effective path to mass production, Stokes explained, allowing the team to meet the tight deadlines delivered by the program office. The team did explore other options, including a traditional composite layup. Composite material is frequently used for fairings across naval aviation, including on the MH-60S, Stokes said; however, the lead time and cost to develop a mold and mass produce the antenna mounts using that method was deemed too time consuming and costly when compared the 3D printing.
Chad King, an avionics engineer with the H-60 FST, said the team started considering additive manufacturing as an option after a site visit from the FMV developer. The company conducted a survey of a nonoperational MH-60 the team has parked in their facility, and provided the team with potential locations for the mounts and other components. The results of the survey led the team to seriously consider the use of additive manufacturing technology.
With the structures engineering team designing the integration plan, creating the drawing and contracting the manufacturing of the antenna mounts and equipment rack, the avionics engineering team has worked to maintain the project’s technical directive and installation data packages.
Because the team was utilizing a novel approach, they solicited input from experts across the board to gain a holistic view of the challenges and opportunities involved in using 3D-printed materials for the mounts. In addition to consulting technical area experts in structures, 3D printing and additive manufacturing, the team also worked with materials engineers, composites, components and electromagnetic environmental effects engineers.
After developing the basic design for the mounts and completing the modeling and design, the team then passed that information along to the Additive Manufacturing team at NAVAIR, which developed the technical data package. This package delineates the requirements and direction needed to 3D print the mounts.
The 3D-printed mounts, along with the rest of the FMV mounting package, are now in the early evaluation stages of production. Stokes said the team is currently conducting a preliminary fit check of all aspects of the FMV modification, structures and avionics, to ensure proper fit and procedures are in place.
“We’re ensuring everything fits, that cables are the appropriate lengths, and that our process is relatively good in terms of instructions,” he said.
The team will complete the fit check and will incorporate any necessary changes into the technical directive, installation data package and design drawings. The NAVAIR Additive Manufacturing team at Patuxent River will then create three more copies of each 3D-printed mount – using the technical data provided by the H-60 FST team – and send those parts to FRCE for finishing. Once those steps are complete, the mounts will move into the next phase of testing: validation on a fleet aircraft at the test squadron at Naval Air Station Patuxent River.
“We’ll be using FRCE facilities to have those painted and finished,” Stokes said. “Then they will be returning to Patuxent River, which is where we’ll be doing flight testing for this modification. Once we get to Patuxent River, we’ll be installing all the components on an aircraft for testing.”
Following validation, the team will conduct a verification of the technical directive on another fleet aircraft; any necessary changes and comments from the validation and verification processes will be incorporated into the technical directive, which will then be released to the fleet to be completed for all applicable aircraft. Validation and verification are standard aspects of any modification, Stokes explained, and must be completed before an airframe change – the type of technical directive the FMV system represents – can be released.
King said the team has been busy during the fit check phase, and that will intensify once the FMV system is installed on a functional fleet aircraft.
“As avionics, we’ll be responsible for testing the functionality of the system once it’s been installed on a fleet aircraft. We’ll also be responsible for generating all of the organizational-level maintenance procedures and periodic maintenance requirements for the system,” he added.
Stokes said the team is looking forward to the next round of development.
“There’s been a lot of work involved in these two specific mounts,” he added.
FRCE is North Carolina’s largest maintenance, repair, overhaul and technical services provider, with more than 4,000 civilian, military and contract workers. Its annual revenue exceeds $835 million. The depot generates combat air power for America’s Marines and naval forces while serving as an integral part of the greater U.S. Navy; Naval Air Systems Command; and Commander, Fleet Readiness Centers.