Safe developed an advanced, multifunctional liner for the interior walls of armored combat vehicles. The Head Impact Protection Spall Liner (HIPSL) combines a layer of crushable honeycomb for head impact protection with layers of fibrous composite for spall containment. Head protection is needed when the vehicle moves violently from an attack, crash, or rollover accident. Spall protection is needed when weapons that overmatch the armor penetrate the interior, releasing hazardous debris including spall particles. Combining these functions into a single liner allows design integration with tailoring for cost, performance, or minimum thickness in the already confined interior space.
Safe is developing a new crashworthy armored helicopter pilot seating system that employs technologies beyond current state-of-the-art that surpass currently passive technology systems with new active sense and control, improved armor, lighter material systems, and increased knowledge about crash safety.
Whole-body vibration is one of the factors causing military aircrew discomfort and pain during and after flight operations. Health risks are a concern after only a few hours of continuous flight at the seating positions on some aircraft. Safe developed a Passive Anti-Resonance (PAR) vibration isolator that isolates an entire helicopter crew seat at its floor attachments. The isolator adjusts automatically to limit displacement during inputs near the resonance frequency. It uses simple passive devices that do not require aircraft power. This approach minimizes the complexity of seat and aircraft integration to keep qualification testing and production costs low enough for successful commercialization.
Safe has developed the Multi-Axis Vibration Reducing and Increased Comfort Seating System. The MAVRIC seats include vibration isolators, a thick pan cushion that comfortably supports the occupant with correct pelvis position, a back recline that keeps the feet on the floor for any recline angle, a recline motion that varies the torso-thigh angle, an adjustment for the PSE position in the back cavity to relieve shoulder weight, and no structure or control protrusions that could press into the legs when seated. These seat features will dramatically improve the workstation ergonomics for E-2D aircrew, reducing acute pain and fatigue, and thereby improving mission endurance. They will also reduce chronic health problems associated with sitting for long periods while being vibrated as occupational exposure.
The built-in vibration isolators are highly effective at reducing whole body vibration (WBV). The MAVRIC cockpit seat reduced the vibration of seated occupants by 70 percent compared to the LE cockpit seat in side-by-side comparisons on a laboratory vibration table. The Air Force Research Laboratory (AFRL) conducted these tests with human occupants exposed to vibration signals replicating E-2D measured floor vibrations. Large vibration reduction was evident through the 1-80 Hz range most associated with human health, as well as overall Root Mean Square (RMS) vibration, which is strongly affected by the blade pass frequency.
Safe developed a multi-functional UUV/Watercraft Cradle System based on a standard 8 foot by 20 foot ISO container to securely stow and transport mission modules. A common cradle enables mission profile reconfiguration, swapping mission modules amongst ships, and otherwise simplifies logistics.
Safe's aircrew-mounted tether system consists of a retracting spool attached to the crew vest via the Emergency Release Assemblies (ERAs) and Modular Lightweight Load-Carrying Equipment (MOLLE) loops on the back of the Aircrew Endurance Vest (AEV). The tether system utilizes an operator control attached to the front of the AEV. The tether uses a cord (rope) rather than a strap or webbing, allowing unrestricted user motion without concerns of strap twist or binding. The tether can be toggled between a fixed cord length and a dynamic cord length, which allows the user to easily move through the aircraft without risk of tangling. A speed sensor automatically locks payout when certain speeds are reached, such as during a crash event or a fall. During this lockout, retraction continues to function normally, increasing safety by allowing the user to return to a safe position before unlocking the unit again. The unit can be unlocked using a shoulder mounted control knob, which has the added benefit of reducing the impact of nuisance locking.
Safe's engineering process emphasizes reduction of concepts to practical designs through early evaluation, testing, and user demonstrations. Because safety products for people require good ergonomics, user feedback is critical to reaching a design that is effective and easy to use. For example, in flight tests of a prototype vibration isolated airplane seat, pilots reported less vibration felt and less acute pain and fatigue after long missions as a result. Pilots also provided feedback for changes that further improved the seat's ergonomics for a final design.
Once Safe's designs reach the right balance of simplicity and effectiveness, they can proceed through formal qualification testing and into rate production and sustainment. Safe's crash energy absorber, for example, is qualified and fielded in the Navy's fleet of MH-60S helicopters. A similar energy absorber, a safety system for off-nominal landing, is qualified for the NASA and Lockheed Martin Orion spacecraft, and flew on the Artemis 1 mission that completed lunar orbits in November 2022. These products are manufactured under Safe's Quality Management System which assures that they are both safe and defect free for a lifetime of use, while providing the objective evidence that all customer requirements and applicable standards are met.
SAFE engineers utilize the latest CAD modeling and simulation software tools for real-time modeling and design confirmation. This enables rapid development of accurate designs. For higher level modeling and simulation, Safe uses outside services that provide the level of sophistication needed while reducing overhead and providing lower-cost solutions in support of Safe's customers.
SAFE employs a multi-axis, multi-loading point static test facility in-house. In addition, an in-house drop tower provides for component level dynamic testing. In concert, these test devices lead to efficient, reduced cost testing activities, and earlier design verification. The opportunity to test components of a design on this scale means problems can be found much earlier, reducing the need for repeat of full-scale system tests that reveal problems. Failure in full scale tests must be followed by re-design, re-work, and repeat of full-scale systems. The use of these test methods during development results in a shorter development cycle and lower costs.
Safe's experience includes development and evaluation (in conjunction with its parent company Point Blank Enterprises), of improved transparent armor for helicopters, wheeled vehicles, and face shield transparencies. Safe personnel also have experience in integrating lightweight armor into structures, such as armored crew seats and mobile missile launchers.
