Estimated reading time 10 minutes, 11 seconds.
Coulson Aircrane (USA) Inc. and SkyTrac Systems Ltd. have joined forces to enhance the effectiveness of Coulson’s next generation air tanker, the C-130Q (Air Tanker 131). The C-130Q is categorized as a Large Air Tanker suitable for Aerial Fire Suppression Missions. It has already been selected by the US Forest Service Next Generation Air Tanker program and is currently undergoing flight tests. It will be fully operational in September 2013.
The C-130Q airframe is equipped with a 3,500 gallon constant flow tank system interfaced with SkyTrac’s ISAT-200A satellite transceiver. These integrated technologies offer a uniquely agile, accurate and efficient firefighting capability, ideally suited to the complex and challenging wildland fire environment of the 21st century.
The Lockheed Martin C-130 Hercules is a four-engine turboprop military transport aircraft. First introduced in 1957, it has a well-earned a reputation as a tough, dependable and safe aircraft. Capable of using unprepared runways for takeoffs and landings, the C-130 was originally designed as a troop, medical evacuation, and cargo transport aircraft. With over 40 models and variants of the Hercules serving in more than 60 nations, it remains one of the world’s most versatile and enduring aircraft.
The C-130 offers unique flight characteristics ideal for fire suppression missions. Coulson’s C-130Q can maneuver safely at low altitude and low speed even in mountainous terrain. The aircraft’s constant RPM variable pitch propellers ensures the C-130Q can fly into areas that would be impossible for other jet aircraft to operate. The aircraft’s inherent Short Takeoff and Landing (STOL) capability means that it can be deployed to even the most austere airfields. Its cruise speed and effective range make it the ideal airframe for covering large areas.
A 3,500 gallon constant flow tank system is installed in the cargo compartment of the Coulson C-130Q. The tank is connected to the cockpit via an Analog Water Tank Controller (AWTC). This controller also interfaces with the SkyTrac satellite transceiver.
The wheeled tank can be removed in 30 minutes for optional cargo operations, and the installation does not compromise aircraft pressurization or restrict aircraft weight and performance. The tank’s gravity system is simpler, lighter, cheaper and faster than pressurized tanks. The gravity tank does not have to have the heavy accessories like an air compressor, multiple smaller tanks, and complex piping. The constant-flow doors provide a dependable and consistent application of retardant. The system can also jettison all 3,500 gallons of retardant in two seconds – a distinct advantage if the aircraft needs to adjust gross weight quickly in an emergency situation.
SkyTrac’s latest transceiver, the ISAT-200A, was launched in 2012. The system has Supplemental Type Certificates (STCs) on a wide variety of airframes. The system interfaces with SkyTrac’s web-based mapping and system management program (SkyWeb). SkyTrac’s application programming interface (API) option allows for the sending of tracking data through to third parties’ Automated Flight Follow (AFF) systems – a requirement for many national level fire coordination agencies. The ISAT-200A is fully compatible with US Forestry Service (USFS), Canadian Interagency Forest Fire Centre (CIFFC), and Australia’s National Aerial Fire Centre (NAFC) AFFs.
Besides the core Iridium modem and GPS tracker, the system’s unique suite of Flight Data Monitoring (FDM) components sets this system apart from all other tracking devices. These components allow for monitoring and communicating an extensive set of operational and maintenance parameters that increase the safety, efficiency and compliance of aviation operations.
The ISAT-200A includes an ARINC 429 interface, analog (8 differential and 1 single ended) and digital (12) discrete inputs, 3 tachometer inputs, an embedded accelerometer, and plethora of communications ports (1/2 duplex RS485 port, full duplex RS422/RS485 port, RS232 port, Ethernet port). It also has a hardened memory module for cockpit audio and data recording. The system can be configured for user- defined exceedance detection and system response (i.e. if an exceedance is triggered, the system is configurable to gather more data, transmit data, and/ or transmit alerts to ground stations, AFF systems, or smart phones).
As well as a cockpit interface (above), the ISAT-200A has a comprehensive web-based ground station interface (SkyWeb) and optional smartphone interface to track aircraft and monitor flight data (see below). SkyWeb has a unique weather overlay capability to aid in mission execution, Wi-Fi for easy transmittal of flight data once the aircraft has landed, and a Crash Hardened Memory Module, a critical element of SkyTrac’s Lightweight Aircraft Recording System (LARS).
The ISAT-200A was designed with Flight Data Monitoring (FDM) and Operational Loads1 Monitoring (OLM) in mind, supporting the US Forest Service Airworthiness Practices Board (FSAPB). It has the interfaces and internal components to provide comprehensive Flight Operational Quality Assurance (FOQA) data to identify potentially problematic operational trends or exceedances long before safety of flight becomes a factor.
For efficient and effective air suppression operations the airframe, water tank, and satellite transceiver must all integrate to provide a seamless firefighting system that optimizes drop placement and coverage.
Aerial suppression is an important element of fighting wildland fires. By its very nature it is flexible and adaptive and offers a unique range and operational reach – it’s sometimes the only way to contain a fire, protect firefighters and property on the ground. However, high levels of coordination are required and missions can be technically complex so it is vitally important to monitor and assess the effectiveness of operations in real time so that the resource can be used to maximum effect.
Australian experiments in drop effectiveness explored some important aerial suppression tactical issues, such as drop coverage, drop accuracy and drop placement. Results from test flights indicate the critical importance of tactical placement and coverage of drops for effective aerial suppression. Drops that are not placed appropriately were ineffective regardless of the suppression chemical used.
Coulson’s more than 25 years of aviation experience supports this hypothesis, and their selection of the C-130Q and constant flow tank was based on the system’s unique ability to place the suppressant precisely where it could be most effective, and in the appropriate coverage. SkyTrac’s ISAT-200A transceiver was incorporated due to the system’s unrestricted communications capability, system reliability, FDM capability, and the system’s ability to easily integrate into the cockpit, the water tank, and third party Automated Flight Follow (AFF) systems.
In the C-130Q the ISAT-200A provides aircraft tracking information, FDM capability, and SatCom voice capability for a broad range of mission uses. In addition, tailored specifically to the aerial fire suppression mission, the ISAT-200A utilizes a standard RS232 single-ended serial connector to interface with the Analog Water Tank Controller (AWTC) on the constant flow tank. Using the ISAT-200A drop event data is transmitted off-board every second and twice a second during drop activation.
This GPS-tagged data includes:
– Tank volume
– Door open
– Door close
All drop event data includes GPS-tags such as date, time, latitude, longitude, altitude, speed and heading. Once transmitted, this data is stored on SkyTrac’s servers at secure data centers. The data is plotted near-real-time on SkyTrac’s web-based mapping and system management program (SkyWeb) or can be ported to any third-party web-based tracking system.
Aircraft position data will typically be transmitted and displayed at a minimum of two minute reporting intervals (RIs) per normal AFF requirements. The RI can be increased automatically if predefined flight exceedances are triggered during the mission or may be changed dynamically using SkyWeb if deemed necessary by ground or air crew. All data is stored for post-mission analysis and lessons-learned training, invaluable for continuous improvement efforts, maintenance programs, and Safety Management System (SMS) programs.
The unique combination of the Coulson C-130Q, constant flow tank system and SkyTrac’s ISAT-200A represent an important advancement in drop placement and coverage that will serve wildland firefighters for decades to come. The system has been tailored to meet the challenging Aerial Fire Suppression Mission, with special attention being paid to distinctive flight envelopes that may be required. The ISAT- 200A system also offers access to flight and mission data for FDM, FOQA, and OLM programs – enhancing safety of flight and efficiency in maintenance. In more ways than one, the Coulson C-130Q represents the best of the next generation of Air Tankers.
