11 Dec 2012, 04:08
15 Feb 2013, 22:51
JPALSbrief Session_D2-4_Wallace.pdf28 Apr 2013, 05:02
"ABSTRACT
The Shipboard Relative GPS (SRGPS) component of the US Department of Defense Joint Precision Approach and Landing System (JPALS) aims to deliver automatic landing capabilities to inbound aircraft aboard aircraft carriers. To accomplish this, GPS data collected on the yardarm needs to be translated to the desired touchdown point (TDP) on the flight deck. This in turn requires that all relative motion between the yardarm and the TDP (ship flexure) be properly accounted for, either via direct compensation or in the accuracy and integrity allocations. Since the magnitude of ship flexure at sea has not yet been quantified a data collection campaign was organized to, in part, allow for a direct assessment thereof. The results of this data collection campaign are presented herein and indicates that ship flexure is on the order of a few centimeters in horizontal and vertical components.
INTRODUCTION
The Joint Precision Approach and Landing System (JPALS) being developed by the United States Department of Defense is intended to provide accurate and reliable guidance information to military aircraft landing on land and aircraft carriers using GPS augmented with other sensors. For land-based operations, Local Differential GPS (LDGPS) will be used, whereas Shipboard Relative GPS (SRGPS) techniques will be employed for aircraft carrier landings.
For the LDGPS case, the situation is similar to the Local Area Augmentation System (LAAS) implemented for civil aviation, with fixed reference stations generating differential GPS data to be sent to the incoming aircraft. The difference between LDGPS and LAAS is that the latter does not attempt to resolve the carrier phase ambiguities.
Although SRGPS is conceptually similar to LDGPS, the major practical difference is that the reference receivers are constantly in motion, as they are now mounted directly on the aircraft carrier. Since the reference GPS antennas cannot be mounted at the aircraft’s desired touchdown point (TDP) on the flight deck (due to operational limitations)), they are typically mounted on the ship’s yardarm. However, since the inbound aircraft requires knowledge of its position relative to the TDP, the GPS measurements need to be geometrically translated to this point. Moreover, this translation must account for all ship motion, most notably the ship’s attitude variations.
Practically, the translation of the GPS reference station data to the TDP is done using the assumed known baseline between the two points (obtained for example from a survey), knowledge of the ship’s attitude and the assumption that the ship is a rigid body. However, in the current context, the latter assumption may not be fully justified. In particular, during high dynamics such as during a turn or while in rough seas, the hull and/or mast of the ship will likely deform (ship flexure). Ultimately, this means that the baseline between the TDP and the GPS receiver is a dynamic quantity.
Since the magnitude of ship flexure has not yet been assessed, a data collection campaign onboard an aircraft carrier was conducted, in part, to address this problem. To this end, GPS and INS data was collected from multiple locations on the ship over several days. This paper presents ship flexure results obtained from data collected onboard an aircraft carrier under operational conditions. The objectives of the paper are as follows:
- Present methods of measuring the relative motion of two points (which, in the current context, is a direct indication of ship flexure);
- Identify the limitations of the above approaches in a practical sense and, where appropriate, propose solutions;
- Provide an initial quantification of aircraft carrier ship flexure at sea; and
- Determine if the estimated ship flexure correlates with ship motion.
The paper begins with an overview of the relevant methodology, including a brief review of methods used to estimate relative motion of two points. Next, the ship trip is described in detail, including the type and location of the various GPS and INS sensors. Finally, the results of the tests are presented and limitations are identified....
...Correlating Flexure and Ship Motion
Finally, an attempt was made to correlate the flexure effects with ship dynamics. The reason for this is that if a strong correlation exists, the flexure effects could, in principle, be compensated in real-time. To this end, an attempt was made to correlate flexure with roll, pitch, roll rate, pitch rate, azimuth rate, lateral acceleration and longitudinal acceleration. Interestingly, the only strong correlation was found to be between the y-axis flexure and roll or lateral acceleration of the ship (the roll and lateral acceleration are closely related). Figure 12 shows the correlation between the y-axis flexure and the lateral acceleration of the ship. As can be seen, the correlation is quite strong, with a correlation coefficient of -0.45 (45% correlation). For the May 6 data (with a higher sea state) the correlation increases to (negative) 78%, indicating that as the acceleration increases, the flexure increases accordingly. Interestingly however, the correlation with ship’s roll is rather small suggesting that perhaps the amount of ship’s roll may also be an important parameter. More investigation is required in this regard.
CONCLUSIONS
This paper set out to investigate the amount an aircraft carrier flexes under operational conditions. The paper began with a brief overview of the basic methodology for accomplishing this task, with focus given to the relevant error equations. A discussion of how to separate the various error sources from each other was also presented.
Using data collected aboard the USS Dwight D. Eisenhower (CVN 69), it was determined that the ship dynamics were too low to reliably estimate azimuth using an EGI. As such, a method of computing the residual EGI attitude errors was developed. Results indicated that this method was able to estimate the relative attitude errors between two EGI units to a few arc seconds. With the EGI attitude errors compensated, the ship flexure errors were then computed. The following conclusions can be drawn from this analysis:
1. Multiple antennas located on the yardarm of the ship exhibit similar short- and long-term flexure estimates.
2. The flexure in the starboard direction is larger than in the forward direction, and this is attributed to the larger variation in roll versus pitch.
3. The standard deviations of the flexure estimates are on the order of 1-2 cm and are approximately constant for all data sets, except when the sea state increases.
4. When the sea state increases, the “horizontal” (x- and y-axis) flexure estimates increase by approximately a factor of 1.6. The “down” (z-axis) flexure appears to be insensitive to sea state, suggesting that the GPS-only errors are dominant.
5. The only correlation between flexure and ship dynamics was found to be between the starboard flexure and the lateral acceleration of the ship. This correlation was found to be 45% for mild sea states and 78% for a sea state of three."
28 Apr 2013, 13:23
28 Apr 2013, 13:45
"...PMA-213 received the second JPALS EDM in October and plans to install it on all CVN, LHD and LHA class ships as part of “Increment 1A.” The system offers critical enabling technology for the CVN-78 ship class, F-35 Lightning II Joint Strike Fighter & Navy unmanned air systems, while allowing retirement of costly, radar-based systems, Lack said. JPALS-compliant aircraft will be compatible with the civil aviation, GPS-based infrastructure when fielded...."
...Extraordinary Environment
But the seagoing JPALS will be a horse (or a LAAS) of a different color. One of the biggest differences will be its data links. For, as development has evolved, carrier-based JPALS has become a generic term applied to a wider data link environment than just the automatic landing portion.... In fact, the Navy’s seagoing JPALS will be the centerpiece of a dedicated, data link-based, communications, navigation and surveillance/air traffic management (CNS/ATM) system, which will be aboard each of its 12 carriers. The Navy needs such a capability to provide safety, airspace management and, of course, surveillance protection against adversaries, as the vessel moves away from the mainland and across oceans, often towards unfriendly territory.
In a way, it will be like picking up a complete FAA air route traffic control center (ARTCC) from the main-land, along with all its radars and infrastructure, and shoehorning it into an aircraft carrier. And since the carrier’s raison d’etre is to extend military air power in all weather, you could even say that the seagoing JPALS’ ultimate purpose is to thread the tip of an autolanding aircraft’s arrester hook through an imaginary 9-square foot (0.83-square meter) box centered precisely 14 feet (4.3 meters) above the pitching and rolling stern of a carrier in very low visibility, by day or night...."
“ABSTRACT
Next generation GPS receivers will take advantage of Spatial processing from a Controlled Reception Pattern Antenna (CRPA) and Ultra-Tightly-Coupled (UTC) and Tightly–Coupled GPS/inertial signal processing to improve their robustness to interference and their performance in a multipath environment. This introduces the potential for failure modes to be introduced into the GPS solution from the Spatial processor, GPS signals or Inertial Measurement Units (IMUs). For high integrity applications such as nonprecision approach or precision approach, the integrated GPS/Inertial receiver must be designed to perform fault detection and exclusion of any hazardously misleading information....
INTRODUCTION
The Joint Precision Approach and Landing System (JPALS) Shipboard Relative GPS concept (SRGPS) is illustrated in Figure 1. The goal of the SRGPS program is to provide a GPS-based system capable of automatically landing an aircraft on a moving carrier under all sea and weather conditions considered feasible for shipboard landings....
29 Apr 2013, 04:10
spazsinbad wrote:After some time I guess the location of PDFs change or they are no longer available. The Wallace and Grommitt PDF mentioned on the first page and at other times in this thread and/or on other threads is no longer available at: http://acast.grc.nasa.gov/wp-content/up ... allace.pdf
So it is attached (maybe searching for it on the web will be successful but whatever)....
29 Apr 2013, 15:17
count_to_10 wrote:Are they really relying on GPS satellites instead of directly determining the relative positions of the carrier and aircraft? Isn't that vulnerable to jamming?
07 May 2013, 23:26
"...Baseline to Objective Transition Strategy (continued).
Radars are currently the primary enabler for precision approach and recovery in low ceiling, low visibility conditions. Automated hands-off fixed wing approach to the carrier deck using differential GPS has already been demonstrated using relative GPS. Insertion of this capability requires significant platform modifications. The Joint Precision Approach and Landing System (JPALS) Program is developing these technologies to replace the antiquated radar Automated Carrier Landing System (ACLS) equipment that is facing obsolescence and driving high sustainment costs. This capability is being developed for rotary wing platform recovery to single spot ships, and is considered a key element of unmanned air vehicle operations at sea. JPALS is planned to replace precision approach systems at military installations and to provide a capability for all-weather recover to temporary expeditionary airfields and landing zones. The strategy is to evolve platform cockpits to provide a Digital Flight Environment (DFE) with the level of integrity to support precision navigation in all phases of flight and weather conditions.
GPS User Equipment (UE) has evolved significantly over the last decade. The latest all-in-view receiver modules incorporate Selective Availability Anti-Spoofing Module (SAASM) GPS receiver cards to prevent spoofing and enhance security of crypto keys. Additional robustness and enhancements are being achieved through the Navigation Warfare (NAVWAR) program with the integration of Controlled Reception Pattern Antennas (CRPAs) that possess significantly improved anti-jam characteristics, such as the GAS-1 and Advanced Digital Antenna Production (ADAP). The next generation of GPS UE, known as Military GPS User Equipment (MGUE), will replace legacy components and be capable of processing both the new M-Code signal and legacy GPS. The M-Code signal possesses even further improved anti-jam characteristics and will be available exclusively for military use. Additionally, MGUE integration will incorporate an enhanced security architecture which provides for layered information assurance and anti-spoofing capability. MGUE and NAVWAR development are managed by the U.S. Air Force led GPS Directorate and PMW/A-170 respectively.
Mandates and Milestones:
JPALS Ship-based Initial Operational Capability (IOC). (2017) The US Navy is the lead for the Joint Service JPALS program, and is responsible for the development of the shipboard solution. JPALS will deployed on the newest aircraft carrier and its assigned carrier aircraft, including C-2A, E-2D, EA-18G, F/A-18E/F, F-35 and MH-60R/S.
Required Navigational Performance (RNP)–2 above FL290 in National Airspace System (NAS). (2018) RNP is a form of performance-based navigation that calls for accuracy of position location on a GPS route to be within a specified number of nautical miles (nm) of intended position. RNP compliance requires 95% fidelity of position accuracy to ensure proper containment for all modes of flight. The GPS receiver must provide Integrity using Receiver Autonomous Integrity Monitoring (RAIM), which ensures that all of the satellites being utilized to determine position are providing useful data. The Federal Aviation Administration (FAA) will require RNP-2 (accurate within a circle with a radius of two nm) for all operations at or above FL 290 in the NAS (similar to Continental United States – CONUS, but also includes Alaska and Hawaii) by 2018.
JPALS Land-Based IOC. (2018) The Air Force is charged with development of land-based JPALS ground stations. Differential GPS will be used to provide an additional military PPS datum reference signal via an encrypted UHF datalink, and an additional civil interoperable SPS datum reference signal via a VHF datalink or SATCOM signal. A fixed station will be installed at every DoD airfield that currently has precision approach capability. A deployable variant will be developed for remote locations....
...3. Funded Enhancements and Potential Pursuits.
Digitally Augmented Ship Approach Sequencing (JPALS). (2018) JPALS will provide for increased ship-to-aircraft relative position accuracy to support ship recovery operations using Shipboard Relative GPS (SRGPS). After launch and during recovery operations, aircraft will utilize data-linked ship position and altitude information to establish more efficient aircraft marshalling procedures and approaches to the ship’s Expected Final Bearing (EFB). The SRGPS link between the ship and the aircraft on the EFB will enable the aircraft to perform very laterally and vertically precise approaches to the ship in all weather and all tactical conditions to minimize aircraft recovery time. Utilization of tighter patterns has already demonstrated time and fuel savings in commercial airport operations, and should provide similar benefits in CVN and multi-spot amphibious ship operations. JPALS precision navigation will require 24 channel GPS receiver upgrades and processing upgrades that enable procesing both L1/L2 PPS GPS signals. The first platform planned to utilize JPALS for marshalling will be the Unmanned Carrier-Launched Airborne Surveillance and Strike (UCLASS).
Digital Airfield Sequencing (JPALS). (2018) Aircraft that are configured with JPALS will be able to immediately take advantage of improved approach sequencing when JPALS units are established at shore bases. Shore based JPALS at military air stations had planned to implement supplemental ground-based signals (Local Area Augmentation Signal – LAAS) that would utilize one-way unique military datalink information for GPS augmentation to enable precision approach capabilities, but that initiative and solution strategy has been deferred. Instead, JPALS equipped naval aircraft will perform GPS augmented precision approach procedures at civilian airfields by leveraging Satellite Based Augmentation System (SBAS) Wide Area Augmentation System (WAAS) signals, which will not require a datalink to receive the correction signal. Air Force is the lead for this program. USAF Mobility and Combat Commands are negotiating the necessity and prioritization of resources to enable MGUE to support this functionality, but it is still currently tracking as a part of the program of record for availability to configured users in 2018....
...D. Recovery.
1. Current Capabilities.
Current shipboard ACLS radars have critical reliability and obsolescence issues. Naval aircraft use Link 4A to conduct assisted approaches and recoveries. The most advanced tactical jets have hands off recovery capability. Helicopters do not have automated recovery. Only the largest surface vessels offer precision approach. Some aircraft employ Instrument Landing Systems (ILS) transceivers for precision approaches to equipped airfields. Most civil airfields are equipped with ILS approaches, but most Navy and Marine Corps airfields typically are not. Aircraft not equipped with ILS are limited to locations with precision radar for alternative low weather ceiling emergency divert recoveries. Receivers that work ILS frequencies must be equipped with filters to prevent FM station interference. The P-3C is the first Navy aircraft certified to fly GPS-based SIDS, STARS and RNP-0.3 approaches.
2. Advanced Research and Technology Development.
Degraded Visual Environment (DVE) Recovery. (2010-2012) The Naval Aviation Center for Rotorcraft Advancement (NACRA) office and PMA261 (H-53 variants) are analyzing technologies and system options that can present an affordable near term solution for this capability gap. Technologies being tested in multiple Small Business Innovative Research (SBIR) efforts include Laser Radar (LADAR), Millimeter Wavelength (MMW) and Passive MMW (PMMW) or other fused spectrum sensors that can “see through” airborne particles to increase SA. The challenge will be to affordably leverage limited existing on-board sensors or to design something that is small and light enough to practically integrate which does not affect flight performance margins.
3. Funded Enhancements and Potential Pursuits.
Digitally Augmented GPS-based Shipboard Recovery (JPALS). (2017) JPALS is a joint effort with the Air Force and Army. The Navy is designated as the Lead Service and is responsible for implementation of shipboard recovery solutions (Increment 1). The F-35 Joint Strike Fighter (JSF) Block 5 will be the first JPALS configured platform. It will start with a temporary solution that will provide needles to the operator to enable a “JPALS assisted” approach. The interim solution will not equip the aircraft to broadcast its position in a manner that can be monitored by JPALS equipment on the ship. Legacy radar will have to be used for the shipboard monitoring of the approach. The Unmanned Carrier-Launched Aircraft Surveillance and Strike (UCLASS) will be the second platform. It will be forward fit with full functionality. JPALS will also be installed on air-wing aircraft (C-2A, E-2C/D, EA18G, F/A-18E/F and MH-60 R/S) to support CVN-79 around 2021-2022. JPALS will eventually replace the ACLS on carriers, SPN-35 radars on LH Class Amphibious ships, and may replace ILS, TACAN, and Precision Approach Radar (PAR) systems at shore stations. JPALS will be interoperable with civil augmentation and FAA certifiable. Shipboard JPALS will use Differential GPS (D-GPS) to provide centimeter-level accuracy for all-weather, automated landings. D-GPS provides a SRGPS reference solution for the moving landing zone. A JPALS technology equipped F/A-18 has demonstrated fully automated recoveries to the carrier. JPALS will also enable silent operations in Emission Control (EMCON) environments.
Digitally Augmented Civil Airfield Recovery (JPALS). (2018) Every aircraft that is equipped with JPALS capability for ship operations will automatically be able to conduct civil airfield GPS precision approaches. UCLASS will be the first equipped aircraft. They will be able to use Satellite Based Augmentation Systems (SBAS) such as the FAA’s WAAS, the Indian GPS and GEO Augmented Navigation (GAGAN), the Japanese Multifunctional Satellite Based Augmentation System, or the European Geostationary Navigation Overlay Service (EGNOS) which was recently activated. JPALS will also be interoperable with FAA civil Ground Based Augmentation Systems (GBAS), which also uses differential GPS to enhance GPS signal correlation for improved position accuracy. JPALS adds the protected military PPS GPS signal, anti-jam and UHF datalink to military approaches but the Civil approaches will utilize the unprotected SPS signal. Civil system interoperability will enable aviators to use hundreds of additional divert airfield options. The Air Force is designated to develop and implement shore station JPALS capability. One JPALS land-based unit (Increment 2) can replace all the existing non-precision approach beacons and precision radars required for each major runway, providing increased capability for less capital investment and sustainment costs. The Army is developing portable tactical JPALS systems that will enable precision recovery in remote expeditionary locations....
...2. Advanced Research and Technology Development.
Military Space Signal and User Equipment Enhancements. (2010-2013) Smaller GPS antennas and AE are being developed for space-constrained aircraft and small Unmanned Aerial Systems. JPALS compatible beam-steering AE is also being developed for JPALS platforms....
Appendix A-4 Cooperative Surveillance
...Mandates and Milestones:
Joint Mode 5 Initial Operational Capability (IOC). (2015) The March 2007 Joint Requirements Oversight Council Memorandum (JROCM) 047-07 calls for Mode 5 Joint IOC in 2015 and Full Operational Capability (FOC) in 2020.
JPALS Ship-based Initial Operational Capability (IOC). (2017) The US Navy is the lead for the JPALS program, and is responsible for the development of the shipboard solution (Increment IA). JPALS will initially be deployed on the newest aircraft carrier and its assigned aircraft, including C-2, EA-18G, E-2D, F/A-18E/F, F-35 and MH-60R/S.
JPALS Land-Based IOC. (2018) The Air Force is charged with development of land-based JPALS ground stations (Increment II). Differential GPS will be used to provide an additional military PPS datum reference signal via Satellite Based Augmentation System (SBAS) Wide Area Augmentation System (WAAS) signals. A fixed station will be installed at every DoD airfield that currently has precision approach capability. A man-pack variant may be developed for remote locations....
...2. Advanced Research and Technology Development.
Military Collision Avoidance (Mode 5). (2011-2012) A Small Business Innovative Research (SBIR) projects is exploring utilization of TACAN Air-to-Air mode to perform aircraft collision avoidance functions within the battlespace. This utility was reportedly demonstrated by Spanish F-18 aircraft. Algorithms were developed to place a ‘range bubble’ around aircraft based upon proximity to another cooperating aircraft who was also operating on TACAN using a specific channel separation.
3. Funded Enhancements and Potential Pursuits.
Improved Ship and Shore Approach Sequencing (JPALS). (2018) F-35B and C early block deliveries will employ a one-way JPALS data-link integration to facilitate Shipboard Relative GPS (SRGPS) aided recoveries. Block four or five will incorporate the full two-way datalink, which will enable ship controllers to manage improved marshalling for more efficient recoveries. Utilization of tighter patterns has already demonstrated time and fuel savings in commercial airport operations, and should provide similar benefits in carrier and multi-spot amphibious ship operations. For more JPALS details, see the Navigation appendix..... [excerpts relevant to JPALS above already]
Fused Sensor and Tactical Data Collaborative Combat ID (CID). (2015) The fusion server integrated into the Joint Strike Fighter (JSF) hosts software that combines and compares target track information obtained from all on-board sensors, as well as from tactical information data-linked from outside sources. If multiple sensor track parameters are similar, a contact attribute can be considered more reliable than if it were derived from a single source data point. Similarly, intelligence and sensor data combinations can be used to discount parameters that may not be as reliable from a single range or condition limited sensor, or one that may be getting spoofed. Automated fusion will produce a higher confidence factor CID solution....
Appendix A-5 Flight Safety
...Shipboard Recovery Animation. (2020) The current MFOQA [Military Flight Operations Quality Assurance] program of record does not include complex analysis and software development required to enable the ability to visualize takeoffs or landings in the highly dynamic shipboard environment. MFOQA Increment 3 is planned to include enhancements that would incorporate ship position and motion into the visualization module to enable accurate portrayal of a flight during embarked operations....
...Structural Prognostics and Health Management. (2015) Joint Strike Fighter (JSF) will field Structural Prognostics and Health Management (PHM) capability in support of mission sortie generation/readiness objectives. Wirelessly downloaded parameters will include fuel state, ammunition state, expendables state, and component health conditions requiring maintenance in order to minimize turnaround time. Real time, accurate down-link of specific component conditions supports CBM [Condition Based Maintenance], which will significantly enhance readiness by enabling maintainers to move from time-scheduled removals and inspections to removing items only when required. Removing components only when they have achieved their tolerance limit of safe operations can also return significant cost avoidances by extending the lives of the parts beyond their engineering estimates, thereby reducing the costs of repairs or replacements. CBM may also result in reduced requirements for spares inventories or deployed spare support footprints...."
03 Jul 2013, 09:34
"Landing on an aircraft carrier is now safer thanks to the Joint Precision Approach and Landing System (JPALS) team from the Naval Air Traffic Management Systems Program Office (PMA-213).
JPALS is an all-weather landing system that uses a Global Positioning System and navigation systems to safely land both land- and sea-based aircraft. JPALS completed its latest round of testing aboard the USS George H.W. Bush (CVN 77) in late May.
The 52-person team spent 11 days aboard the carrier testing the latest JPALS software with two F/A-18C Hornet aircraft from Air Test and Evaluation Squadron (VX) 23, and an MH-60S helicopter from Air Test and Evaluation Squadron (HX) 21, based at Naval Air Station Patuxent River. A modified Beechcraft King Air flying from St. Mary’s County Airport was also used as a test bed aircraft.
“The Hornets flew 65 low approaches to touch-and-go or full-stop landings during our two weeks on CVN 77,” said Lee Mason, PMA-213’s JPALS Ship System integrated program team lead. “The King Air completed 29 low approaches. So far, we are very pleased with the results. The system is expected to achieve tremendously improved landing accuracy.”
With the completion of this two-week test period, the JPALS program transitioned into the second phase of integrated test, establishing the system requirements verification for JPALS, Mason added.
“The data generated from this two-week, at-sea period is undergoing detailed analysis by our experts. This analysis will, in turn, be used to validate and verify the system is accurate and working,” said Capt. Darrell Lack, PMA-213 program manager.
Later this summer, JPALS is scheduled to complete additional at-sea testing to further refine the verification and validation effort and enable the completion of the operational assessment of the JPALS ship system, which is needed to progress to the program’s next milestone, Lack added.
“JPALS will provide adverse weather, adverse terrain, day and night, and survivable precision approach and landing capability that supports service and multi-national interoperability,” Lack said. “It is particularly suitable for the F-35, future aircraft and unmanned air vehicle operations at sea.”"
03 Jul 2013, 09:37
"The U.S. Navy successfully launched an EA-18G Growler on June 25, kicking off the second phase of manned aircraft launch tests using the Electromagnetic Aircraft Launch System (EMALS).
The new aircraft carrier catapult system, which is replacing steam catapults beginning with the new Gerald R. Ford-class carriers, commenced aircraft compatibility testing (ACT) phase two from the land-based test site at Joint Base McGuire-Dix-Lakehurst, N.J.
“As we move into the second phase of aircraft testing, I’m confident we’ll continue to see the breadth of EMALS’ robust design and operational capability,” said Capt. James Donnelly, program manager for Aircraft Launch and Recovery Equipment Program Office (PMA-251) who oversees the EMALS.
George Sulich, EMALS integrated test team lead, said this phase of testing will simulate various carrier situations, including off-center launches and planned system faults to demonstrate that the aircraft can meet end-speed and validate launch-critical reliability.
The team expects to conduct more than 300 launches this year, Sulich said.
“During ACT 2, we will launch every aircraft currently utilizing today’s carrier catapults, with the exception of the E-2C Hawkeye,” Sulich said.
The EMALS team completed the first phase of aircraft compatibility testing fall 2011 with 133 manned aircraft launches, comprising the F/A-18E Super Hornet, T-45C Goshawk, C-2A Greyhound, E-2D Advanced Hawkeye. The team also had an early opportunity to launch the F-35C Lightning II to evaluate any technical risks.
This was the first EMALS launch for the Growler, an electronic attack variant of the Block II F/A-18F Super Hornet and Navy replacement for the EA-6B Prowler. This year, the F/A-18 family of aircraft is celebrating its marks the 35th anniversary.
“We’ve now launched each of the Navy’s newest aircraft using EMALS,” Donnelly said. “The system is definitely demonstrating its ability to meet fleet requirements by expanding the launch envelope.”
EMALS is a complete carrier-based launch system. It delivers necessary higher launch energy capacity; substantial improvements in system maintenance; increased reliability and efficiency; and more accurate end-speed control. Its technologies allow for a smooth acceleration at both high and low speeds, increasing the ability to launch aircraft with less stress on the ship and its systems.
EMALS is designed to expand the operational capability of the Navy’s future carriers to include all current and future carrier air wing platforms – lightweight unmanned to heavy strike fighters."
03 Jul 2013, 09:39
"An EA-18G Growler, the electronic attack variant of the F/A-18 Super Hornet, was launched for the first time June 25 using the Navy’s new Electromagnetic Aircraft Launch System (EMALS), which is replacing steam catapults, beginning with the future Gerald R. Ford-class carriers."
03 Jul 2013, 10:28
03 Jul 2013, 13:41
spazsinbad wrote:I found that the NavAir Video above did not work for me no matter what I tried. Here is the same Utube version I'm guessing?
Navair - EA-18G Growler Airborne Electronic Attack Aircraft First Land-Based EMALS Launch [720p]
Published on Jul 2, 2013
http://www.youtube.com/watch?v=s2dOhjut5vE
10 Jul 2013, 03:15
"On this edition of Airwaves, weather watchers keep their eyes to the sky to ensure aircrew safety during tests; plus, a "magic carpet" makes carrier landings safer for pilots; and the Navy's newest unmanned air vehicle flies high above Palmdale, Calif., during its first flight.
&
(Transcript) "A new landing system aims at making carrier landings safer.
Engineers at manned flight simulator are testing magic carpet – a landing system designed to reduce the workload of pilots and improve carrier touch-down performance. By using manned flight simulator, engineers can test the system under normal and adverse conditions, giving them a better idea of how the system will respond at sea. The goal is to reduce landing variability allowing pilots to focus more on the mission.
James Denham / Senior Engineer, Aeromechanics Division 4.3.2
“Airplanes today have very good computer systems, redundant and reliable flight control computers. We are capitalizing on those systems and then providing augmentation in the flight path access for the airplanes. So we are taking a lot of the tasks that the pilot has to do manually and letting the computer take care of those tasks and give him direct control of what he is trying to do which is fly the flight path and line up the touchdown.”
In addition to increasing safety, the system is expected to save on training costs for carrier landing signal officers. Engineers are currently testing the system for use on the Hornet and F-35C."
03 Aug 2013, 21:57
"JOINT PRECISION APPROACH AND LANDING SYSTEM (JPALS) pp 28-29
Joint Precision Approach and Landing System (JPALS) is a GPS based system that will be the replacement for the current ACLS/SPN-46 system. Unlike the SPN-46 that uses radar on the boat to track an aircraft, JPALS works by comparing the GPS position of the carrier and the GPS position of the aircraft. A relative navigation (Rel Nav) solution is calculated and displayed as guidance in the cockpit. Initial tests were conducted in 2000 with an F-18 to prove that the concept worked. JPALS should IOC in 2014 and will start to be retrofitted on Hornets. H-60’s and E-2D’s should start to see it in 2017. It will be the only approach guidance on NUCAS (Navy Unmanned Combat Air System) and the F-35. Every carrier will be equipped by 2024.
How is it better? It will be GPS based and is jam resistant. Instead of an operator in CATCC having to lock up an aircraft with the SPN-46 radar, only a data link between the ship and aircraft needs to be established making the system more reliable. This link will be established when the aircraft gets within 200 miles of the carrier, not at 5 miles behind the ship prior to tip over. The linked Rel Nav solution will also act like a TACAN and give ships position out to 200 miles. The link transmission, like MIDS, uses spread spectrum transmissions so it does not give away position and can be used during EMCON conditions. Mode I approaches will also be more accurate. The SPN-46 radar loses the aircraft at the round down. Past the round down glide slope guidance is basically an average of the last few seconds of the flight path. That is why during a Mode I the hornet freezes control input commands in the last 2 seconds before touchdown. The JPALS GPS guidance will be accurate all the way to touchdown. The Air Force and Army are funding a ground based JPALS system that can be easily setup at any airfield giving the Hornet an actual precision approach besides a PAR.
How will it affect me? With no need for interaction with an operator in CATCC, JPALS may be available during Case I approaches providing better gouge through the approach turn then the ICLS. Drop locks at 3 miles should not be a problem anymore; if you have JPALS in Marshall you’ll have it on final. The pickle switch on the platform will be connected to the data link and transmitted to the aircraft providing a true “W/O” discrete in the HUD and the ability to wave off a UAV. The ships final bearing will also be automatically linked to the aircraft and instantaneously updated in the cockpit, greatly enhancing SA to which direction the ship is turning while we are trying to land.
The mechanization and cockpit displays are still in the design phase. Do we want it to look just like ACLS or ICLS? Is it going to be called needles, bullseye, or _______? Should final bearing automatically be set as a course line? Is there a better way than the old way to do business? As fleet operators and LSO’s if you have any suggestions or ideas please let us know. In a few years JPALS will be a great tool to help us get the Air Wing aboard safely."
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