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The Indian Head Division, Naval Surface Warfare Center (IHDIV, NSWC) CAD Engineering Division is conducting a program to evaluate the laser components which comprise the Canopy Fracturing Initiation System (CFIS) currently installed on the T-6A Texan or JPATS (Joint Primary Aircraft Training System) aircraft. The T-6A Texan is the first aircraft used by the military to train future pilots. The CFIS is an element of the pilot emergency escape system which weakens the canopy in the path of the ejection seat. The CFIS is comprised of three differing configurations (Internal, External, and Seat Motion) which generate a laser pulse that is distributed through a fiber optic energy transmission system. This pulse, in turn, initiates explosive components which weaken the respective canopies. All of the CFIS laser types are flashlamp-pumped, neodymium glass lasers which are located at various positions in the aircraft cockpit area. This paper builds on the previous 2008 SPIE paper (Conference 7070) and presents further CAD Engineering Division test results and analysis which were utilized to evaluate the functional performance of the three CFIS laser signal generators after their being installed fleet applications over a period of time.

The Indian Head Division, Naval Surface Warfare Center (IHDIV, NSWC) has been involved with the laser initiation of energetic materials over the past 18 years. Specifically, the IHDIV, NSWC has been leading efforts in the basic research into laser ignitability of various energetic materials, developing cartridges and Cartridge Actuated Devices (CADs) incorporating this research, and ultimately implementing these new devices into a variety of aircrew escape system and weapon system applications. This paper presents an overview of one of these on-going programs: the effort to determine the laser ignitability characteristics of the MTV (Magnesium Teflon Viton) initiation material used in Mk 117 Mod 0 Jet Assisted Take-Off device. This example highlights one of the current efforts being conducted at the IHDIV, NSWC and supplements the previously presented technical papers offered at various the AIAA Conferences and other related symposia. The laser ignition capability is currently supporting several Department of Defense CAD/PAD programs. This paper will highlight the efforts underway to support an effort to determine the laser ignitability characteristics of the MTV (Magnesium Teflon Viton) and NOSIH-AA6 double base propellant used in the Mk 117 Mod 0 Jet Assisted Task-Off (JATO) device. This investigation is one phase of a larger investigation into several anomalies associated with this JATO and the BQM-74E Aerial Target system. FIELDED SYSTEM AND INVESTIGATION: BACKGROUND: This paper presents the IHDIV, NSWC current capability to study the laser ignition characteristics of various energetic materials used in various CAD/PAD (Cartridge Actuated Device/Propellant Actuated Device) applications. Determining the laser ignition characteristics of an energetic material greatly enhances the overall understanding of how this material reacts to a stimulus and supplements the standard mechanical, chemical, and ignition test parameters generated when an energetic material is studied. The IHDIV, NSWC approach to evaluating the laser ignition characteristics of energetic materials utilizes a 400 Watt Coherent, Inc. carbon dioxide (CO2) laser (10.6 micrometer wavelength) with a developed test methodology to generate two critical energetic material characteristics: a 50% ignition threshold level and identifying the time to first light (or ignition delay). The details of the test approach will follow. Photo 1: BQM-74E Aerial Target Launch The U.S. Navy has utilized the BQM-74E Aerial Target (Photo (1)) extensively for various training and weapon system tests over the past several years. The BQM-74E Target utilizes an on-board jet engine to provide over 200 pounds of thrust to sustain flight. The dual Mk 117 Mod 0 JATOs provide a combined thrust of approximately 7,000 pounds to launch the target both from land-based and from shipboard platforms. 1 41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit 10 13 July 2005, Tucson, Arizona AIAA 2005-3517 This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. Recently, the Navy has experienced several anomalies in which the JATO devices have either failed to ignite or have not provided continuous sustained thrust shortly after ignition. In these cases, the asymmetric thrust resulting from only one successful JATO have resulted in the complete loss of the aerial target (Photos (2), (3), and (4)). These photos were taken during a 3 May 2004 incident at the Naval Air Warfare Center – Weapons Division, Point Mugu, CA. e r Photo 5: JATO Initiator Configuration LASER IGNITABILITY TEST METHODOLOGY: In general, the test methodology adopted for all of the IHDIV, NSWC laser ignitability programs is very similar. Utilizing the carbon dioxide laser previously described, a mask with a 0.10-inch diameter hole in the center is used to limit the generated laser beam (normally the beam is 1.0-centimeters in diameter at the 1/e points). This 0.10inch beam delivers a controlled thermal input to the energetic material samples. For the NOSIH-AA-6 propellant, a series of 0.25-inch cube propellant samples were used. For the MTV ignition material, a series of short, extruded cylinders were used. All of these samples are centered in the test chamber in brass holders. These samples were prepared specifically for this investigation.

The Indian Head Division, Naval Surface Warfare Center (IHDIV, NSWC) has completed an advanced development program to design and test an optical detonator for use in various aircrew escape system applications. This detonator accepts a 1.06 micrometer wavelength laser input stimulus and generates a fully developed shock wave output. This shock wave output replicates the output of Shielded Mild Detonating Cords (SMDC) and other linear explosive components currently used in the fleet. BNCP is the primary energetic material of this detonator, which also utilizes HNS to generate the final output. Functional tests of this detonator have included a 20 unit Neyer Sensitivity test at ambient condition to determine the initiation thresholds of this design, plus performance tests conducted at -65 °F, 70 °F, and 225 °F. Additionally, several detonators were environmentally stressed through temperature shock, humidity, and altitude cycling for periods of 14 and 28 days prior to functional testing. All of these test results were conducted at the "all-fire" energy level of the detonator and met the current SMDC output requirement of producing a minimum of a 0.040 inch indent in an aluminum block. At the conclusion of the functional test program, a delta qualification program was conducted. The detonator successfully completed these tests and is now fully qualified for DoD use. The detonator design, all of these test results and analysis, and future plans for this detonator are presented in this paper. BACKGROUND Implementing lasers and laser initiation technology into various aircraft escape system and related applications has been a primary objective of the U.S. Navy for several years. Replacing the current explosive transfer lines with inert fiber optic lines is This paper is declared a work of the U.S. Government and is not subject to copyright protection in the United States. one of the major benefits of laser initiation technology for aircraft signal transmission system applications. To achieve this program objective, the development and qualification of a laser-ignited detonator is critical. The IHDIV, NSWC development program for a laser ignited detonator was initiated in the early 1990's. Design requirements for this detonator were established at this time (Table (1)). To meet these requirements, a HMX based detonator was originally developed''. After several hundred design verification and qualification functional tests, output performance shortcomings were identified with this HMX detonator design. After temperature conditioning and temperature cycling, the generated output did not consistently achieve the required 0.040-inch indent. An extensive failure investigation of the HMX design was conducted by IHDIV in conjunction with the Department of Energy, Sandia National Laboratories, and the University of Maryland at College Park. The root cause of this seemingly temperature related effect was never fully identified. To continue laser technology implementation into escape systems as planned, an alternate detonator design utilizing a new energetic material was developed. Detonator Requirements All Secondary explosive device Flat optical window configuration Shielded Mild Detonating Cord (SMDC) tip output 0.040 inch indent in a 2024-T6 aluminum dent block Hermetically sealed Structurally sound, all reactants confined No proprietary components Transition government developed technology to industry for competitive procurement___ Table 1: Laser-Ignited Detonator Design Requirements 1 American Institute of Aeronautics and Astronautics (c)2000 American Institute of Aeronautics & Astronautics or Published with Permission of Author(s) and/or Author(s)' Sponsoring Organization. The new detonator design utilizes BNCP as the ignition charge and as the Deflagration to Detonation Transition (DDT) material. An HNS pellet has been added to the design to replicate the current explosive transfer line ballistic output. BNCP [Tetraammine-cis-bis(5-nitro-2//-Tetrazolato-N) Cobalt (III) Perchlorate] is an energetic material developed by the Department of Energy for use in several specific applications. BNCP replaces the HMX material in the original detonator design and provides the ballistic capability to meet all the established detonator performance requirements. Several vendors have developed the capability to fabricate various particle sizes of BNCP for a wide range of applications. Pacific Scientific of Chandler, AZ and The Ensign-Bickford Company of Simsbury, CT have supplied BNCP to support this detonator design effort. Sandia National Laboratories has released a Material Specification (SS707897) for BNCP. To validate the fabrication process for this new energetic material, IHDIV conducted a series of independent tests with the University of Maryland at College Park and with Quantic Industries, Inc. of San Carlos, CA. The results of these characterization tests on a range of particle sizes of BNCP reveal both vendors offer comparable grades of BNCP. A Differential Scanning Calorimetry (DSC) plot (Figure (1)) is shown as an example of the data generated as part of this effort. A complete U.S. Navy characterization program, in accordance with Department of Defense instructions, is underway for this energetic material. SM.pl*: BNCf P/N0*Etia9-01 H/0 BU StZK O.OOO3 MB HathOtt BNCP 100/2/400 COMMnt: Z C/M1N. Hg-M\ OJ/WIH. Fill: PRIME. 761 Operator: EDWARD RAKOS Hun D»t»: 29-JU1-9* 1* 1 Figure 1: BNCP DSC Sample Plot (Quantic Industries, Inc.) Based on this testing, a new detonator design was developed (Figure (2) and Photo (1)). This detonator includes a BNCP/carbon black blend ignition mix, a BNCP DDT column, and a HNS (Hexanitrostilbene, Type I) output tip. The output tip replicates the signal provided by current fleet linear explosive products like Shielded Mild Detonating Cord (SMDC), Flexible Confined Detonating Cord (FCDC), and Thin Layer Explosive (TLX). These linear explosive products would be replaced by laser/fiber optic line components in escape system applications. BNCP DDT Column Sapphire Window (6 increments BNCP)

The Indian Head Division, Naval Surface Warfare Center (IHDIV, NSWC) is the lead service for cartridges, Cartridge Actuated Devices (CADS), and Propellent Actuated Devices (PADS) for the Department of Defense. The Signal Transmission System (STS) is comprised of these devices and performs the critical function of providing the input stimulus required to function the cartridges, CADS, and PADS at their designated times, Since 1988, the CAD Research and Development/Product Improvement Program Branch has been active in the study and implementation of new methods of generating and transmitting these input signals. Implementing laser energy and fiber optic lines to perform the STS requirements has been the primary objective of this effort. This paper presents the test results of a temperature sensitivity study of various fiber optic line configurations. The configurations studied include the STS for U. S. Navy aircraft escape systems (environmental conditioning data was initially presented at the Safety and Flight Equipment (SAFE) National Symposiums in 1995 and 19961.2) and the NASA X-38 Crew Return Vehicle STS. The objective of the tests was to evaluate the effects of both high and low temperatures on the optical transmission of the fiber optic lines. This was done by thermally cycling each line from room temperature, to -65 “F, to +225 “F, and back to room temperature. Transmission measurements were made at 5 minute intervals throughout the entire two hour cycle. Initial test results for the X-38 lines confirm a significant reduction in transmission at both high and low temperatures which was also experienced during the X-38 Captive Carry tests. Comparison with the Navy STS lines are presented to determine if any temperature sensitivity exists for this

The Indian Head Division, Naval Surface Warfare Center (IHDIV, NSWC) is the lead service activity for cartridges, Cartridge Actuated Devices (CADs), and Aircrew Escape Propulsion Systems (AEPS) for the Department of Defense. In this role, the CAD Research and Development/Product Improvement Program'Branch has been actively investigating newly developed energetic materials for use in aircrew escape applications. Pacific Scientific, Energy Dynamics Division, has been active in the design, development, and production of detonators, cartridges, and CADs for these systems since 1968. Currently, Pacific Scientific is optimizing the production process for a new energetic material, BNCP, for use in these components. BNCP (Tetraamminebis (5-nitro-2H-tetrazolateo-N) cobalt (III) perchlorate) accepts an input stimulus and produces a detonation output. This paper presents a series of preliminary screening test results for a Government-owned electrical detonator design where BNCP has replaced the current ignition material. These test results supplement the prior findings which evaluated BNCP in an optical detonator configuration and were presented at the Joint Propulsion Conference in 1996 (AIAA Paper #96-2619)'.