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Frequently Asked Questions (2006)

General Questions
Phase 1 Questions
Phase 2 Questions
Phase 3 Questions

General Questions

Question:  What is Capstone?

Answer:  The Alaskan Region's "Capstone Program" is a technology focused Safety Program in Alaska which seeks near term safety and efficiency gains in aviation by accelerating implementation and use of modern technology. Capstone links multiple programs and initiatives under a common umbrella for planning, coordination, focus and direction and develops capabilities and requirements jointly with FAA, the Alaskan community and aviation industry in a manner consistent with future NAS plans and concepts, and implements in a manner leading to self-equipage.

Capstone is an accelerated effort to improve aviation safety and efficiency through installation of government-furnished Global Positioning System (GPS)-based avionics and data link communications suites in commercial aircraft. Compatible ground systems, equipment, and services will also be provided. The name "Capstone" is derived from the program's effect of drawing and holding together concepts and recommendations contained in reports from the RTCA , the National Transportation Safety Board (NTSB), the Mitre Corporation's Center for Advanced Aviation System Development (CAASD) , and Alaskan aviation industry representatives. In addition to the avionics suites, Capstone will deploy a ground infrastructure for weather observation, data link communications, surveillance, and Flight Information Services (FIS) to improve safety and enable eventual implementation of new procedures. A successful Capstone demonstration will help reduce FAA's risk of nation-wide transition to the future National Airspace System (NAS) Architecture 4.0. The Capstone program began in Southeast Alaska in FY2001.

Question:  What is ADS-B?

Answer:  ADS-B is the acronym for Automatic Dependant Surveillance - Broadcast, a new technology that allows pilots in the cockpit and air traffic controllers on the ground to "see" aircraft traffic with much more precision than has been possible ever before.

Radar works by bouncing radio waves off of airborne targets and then "interpreting" the reflected signal. ADS-B doesn't need to interrogate targets to display them. Rather, it relies on the satellite-based global positioning system. Each ADS-B equipped aircraft broadcasts its precise position in space via a digital data link along with other data, including airspeed, altitude and, whether the aircraft is turning, climbing or descending. This provides anyone with ADS-B equipment a much more accurate depiction of air traffic than radar can provide.

Unlike conventional radar, ADS-B works at low altitudes and on the ground, so that it can be used to monitor traffic on the taxiways and runways of an airport. And it is effective in remote areas or in mountainous terrain where there is no radar coverage, or where radar coverage is limited.

One of the greatest benefits of ADS-B is its ability to provide the same real-time information to pilots in aircraft cockpits and to ground controllers, so that for the first time, they can both "see" the same data.

Pilots see the ADS-B equipped aircraft on their cockpit displays via direct air-to-air transmissions between the aircraft. Controllers see the ADS-B equipped aircraft on the air traffic control displays via the same transmission from the aircraft, but these transmissions are received by a ground infrastructure of ground stations and then sent to the air traffic control center.

Figure 1: ADS-B Concept
Figure 1: ADS-B Concept

Question:  What is FIS-B and TIS-B?

Answer:  FIS-B is Flight Information Services - Broadcast. It is the uplink, from the ground, of weather and non-control ATC information to the cockpit. Examples of products currently being uplinked to the cockpit include NEXRAD weather radar, METARS, and TAFS. In the future, products including icing, PIREPs, and Temporary flight restrictions (TFRs) could be uplinked as well.

TIS-B is Traffic Information Services – Broadcast. It is the uplink of traffic information derived from ground-based surveillance radars into the cockpit. This information is displayed on the cockpit display in a similar fashion to the ADS-B traffic information. TIS-B allows Capstone equipped users to see other aircraft prior to those aircraft being equipped with Capstone avionics, while in an area with radar coverage. Currently, only transponder equipped aircraft positions as seen by the radar will be uplinked.

Figure 2: FIS-B Concept
Figure 2: FIS-B Concept

Figure 3: TIS-B Concept
Figure 3: TIS-B Concept

Question:  Are there additional NEXRAD radars planned for the FIS-B uplink?

Answer:  There are no plans to deploy any additional NEXRADs in Alaska. All current NEXRADs in Alaska are available now as part of the FIS-B uplink.

Question:  What is Flight Monitoring?

Answer:  Flight Monitoring is a service offered to the flight dispatch or aircraft owner on the ground to allow them to monitor the location of their Capstone equipped aircraft. Using the same avionics’ ADS-B transmissions, the FAA’s ground infrastructure, the World Wide Web and internet, these users can use their personal computers to graphically track the location of their aircraft.

Question:  How will ADS-B transmissions be used by AFSS, CAP, and other aspects of the SAR process?

Answer:  Currently, all ADS-B transmissions that are received on the ground and sent to the Anchorage air traffic control center are recorded in case they are needed for SAR. The SAR process on this recorded data is performed at the Anchorage air traffic control center when they are notified of a missing aircraft. Once information about the missing aircraft is found, personnel at the Anchorage air traffic control center contact the appropriate SAR personnel with the information. A research effort is now underway to provide AFSS personnel with Capstone ADS-B position reports to determine the usefulness of this kind of information for flight service.

Question:  How would position transmissions using ADS-B be useful compared to other SAR enhancement mechanisms?

Answer:  The UAT derived information is a very accurate latitude-longitude and altitude position of the aircraft. For SAR, the last known position of the aircraft is usually the piece of information needed. However, the last known position derived from the ADS-B data does not necessarily determine the location of the missing aircraft as the aircraft may have been flying out of coverage of the ground station or be below coverage of the ground station. This ADS-B information will be used in conjunction with other SAR information (e.g., ELT, flight following) to locate a missing aircraft.

Question:  What progress has Capstone made thus far in installing infrastructure?

Answer:  In Western Alaska, Capstone has installed 10 ground stations in the Yukon Kuskokwim (YK) Delta region and has provided the Capstone suite of avionics to approximately 200 aircraft in the YK Delta. Five of these ground stations are enabling air traffic controllers to provide IFR services in those areas. All 10 ground stations are providing FIS-B uplink services as well as the ingest of data for flight monitoring by users. Capstone has also provided GPS approaches and AWOS weather sensors at 10 airports thus enabling IFR approaches to those airports. In South East Alaska, Capstone has installed ~13 ground stations and has equipped approximately 175 aircraft with avionics. The ground stations, when operational, will enable IFR services, and provide FIS-B uplink services as well as flight monitoring services. Capstone has also been demonstrating TIS-B, FIS-B, and flight monitoring services in the Anchorage area.

Question:  Is the FAA going to require Capstone instruments are installed on all aircraft, or will it be an optional accessory?

Answer:  Voluntary self equipage is the key to modernization. Generally, this takes place when new capabilities are available and affordable. The Capstone initiative will be a catalyst for voluntary equipage as it demonstrates capabilities not found with current or "legacy" technology and it helps make those capabilities more affordable. The Capstone Program will initially provide commercial air carriers with an opportunity to voluntarily equip their aircraft with the specified avionics at government expense. As part of the National ADS-B program, there is discussion to eventually mandate “ADS-B out” (i.e., ADS-B transmission from the aircraft) as ADS-B will become the primary means of surveillance in the future NAS instead of radar. It is not clear at this time whether this mandate will affect airspace in Alaska.

Question:  If not required, how can the FAA be assured Capstone will increase safety and not be a waste of resources if aircraft operators don't spend the time and money to upgrade?

Answer:  The Capstone Program is based on the presumption that operators will equip their aircraft and participate in the program because they will derive immediate safety benefits from the avionics and ground infrastructure, and eventually will be able to implement more efficient operational procedures. It has been demonstrated that most commercial operators in the initial demonstration areas have voluntarily equip their aircraft because of the derived benefits. There are a relatively small number of commercial and private aircraft operating in the demonstration area not equipped with ADS-B and the other systems, and they will not benefit from Capstone capabilities. Because of the large benefits seen to-date with the Capstone program, it is believed that many more commercial and private aircraft will self equip as the services are offered in other parts of the state.

Question:  Does the FAA believe there are flight safety problems in Alaska? If so, is Capstone the remedy for those problems?

Answer:  Alaska has approximately 10% of the nation’s air carriers or commercial operators. Historically, this 10% generates approximately 35% of the nation’s air carrier / commercial operator accidents. During the three year period from 1994 to 1996, there were 112 involving Alaska's air carrier /commercial operator's - a study of those accidents indicated that 38% might have been avoided by availability of information in the cockpit of the type provided by modern equipment (position relative to terrain and traffic, and "real time" weather information). The Capstone Initiative has validated these safety projections. The Bethel and Y-K delta area is the Capstone initial test bed; it is served by approximately 25 percent of the commercial aircraft in Alaska and it has a proportionate number of Alaskan accidents. The 2004 safety study by MITRE and the University of Alaska, Anchorage states that "from 2000 through the end of 2004 the rate of accidents for Capstone equipped aircraft was lower by 47%." Capstone is one of the several safety initiatives that can help remedy the aviation safety problems in Alaska.

Question:  Does Alaska get any special attention versus the rest of the country on aviation issues due to the large amount of aviation uses in the state?

Answer:  Yes.  Alaska is the focus of several special safety programs; the Capstone Initiative is one such example.

Question:  Does the FAA plan Capstone to be a test leading to statewide implementation?

Answer:  The future National Airspace System architecture is based on GPS-driven systems for navigation and surveillance. This is the heart of the Capstone Program. Ultimately, the entire Alaskan air transportation system will reflect the approach adopted for national implementation. The Capstone Program is intended to demonstrate new safety and efficiency can be delivered to the equipped aircraft in a cost-effective manner. Because of the success of the initial Capstone demonstrations, plans are now underway to expand the concept statewide as well as to the lower 48. The Capstone program initiatives and hardware will be consistent and interoperable with the lower 48 implementation.

Question:  Will the ground based systems be ample for a statewide system or will a switch to satellite technology be needed first?

Answer:  FAA initially considered the feasibility of using a satellite-based support system for the Capstone Program. Under this concept, each aircraft would report its GPS-based position, and receive data link messages, directly to/from a satellite system which would then relay this information to the Anchorage air traffic control center. Under this concept, there would be no need for a large number of ground stations. Unfortunately, the current operating costs for a satellite-based communications system to support the Capstone Program are too great. In the future, however, the satellite-based approach might become both feasible and cost advantageous, if so, it could then be used for expansion of the Capstone service area to areas where it is cost prohibitive to install ground stations.

Phase 1 Questions

Question:  What avionics suite are the commercial aircraft using in the Phase I Yukon-Kuskokwim delta area?

Answer:  The Capstone Phase I aircraft avionics suite consists of the following Garmin equipment: GX-60 GPS receiver/comm or GX-50 GPS receiver—these are approach certified GPS receivers which include a high definition moving map display. The aircraft's position relative to airports, runways, VOR's, NDB's, intersections, and SUA's can be viewed on the moving map display. The receivers are TSO-C129a Class A1 approved for IFR non- precision approach operation. MX-20 Multifunction Display - Displays terrain, flight plan and weather information on a 6 inch diagonal color screen. The GDL90 UAT (Universal Access Transceiver) data link - Transmits and receives ADS-B (Automatic Dependant Surveillance - Broadcast) information, which includes position, course and speed, and altitude. The UAT also receives ground-based transmissions of FIS-B and TIS-B information for display on the MX20. The position source for the ADS-B data transmitted from the aircraft is derived from the TSO145/146 WAAS enabled GPS source in the GDL90.

Question:  How much did the Capstone Phase I avionics cost?

Answer:Under the Capstone Program initial demonstration, the government-furnished avionics were provided at no cost for participating air carrier aircraft. In western Alaska, this primarily includes small single- and twin-engine propeller-driven airplanes which are operated under VFR. The installed cost for the Capstone avionics package for these type airplanes is in the range from $15,000 to $20,000. As with most modern electronics devices, it is expected the price for a privately purchased avionics suite will fall dramatically, perhaps to one-half that initially paid by the government once demand and quantity production increases. Furthermore, the FAA procurement contract having covered many of the nonrecurring, up-front engineering and production costs will result in lower costs as there is no need for the manufacturer to pass these costs on to the consumer.

Phase 2 Questions

Question:  What avionics suite is the Capstone program providing commercial aircraft serving the Phase II Southeast area?

Answer:  Two kinds of avionics suites are being offered to the Phase II aircraft:
1) A Garmin suite similar to those offered in Phase I, and 2) a more advanced Chelton suite better suited to IFR equipped aircraft. The Chelton suite consist of the following: A Chelton EFIS which includes two Individual Display Units (IDU)'s consisting of a Primary Flight Display (PFD), and a Multifunction Display (MFD). There is also a Alttitude & Heading Reference System (AHARS), a Air Data Computer (ADC), a WAAS enabled GPS and a Garmin GDL-90 Universal Access Transciever (UAT). The Garmin suite consists of the MX-20 MFD, a CNX-80 WAAS navigator and a GDL-90 UAT.

Phase 3 Questions

Question:  What does Phase III Capstone Statewide expansion mean?

Answer:  Capstone is planning on expanding the services to cover the areas of the state where there is significant air traffic with the goal of expanding the demonstrated safety benefits to a larger area. The plan is to add many more ground stations, GPS approaches, and RNAV/RNP routes beyond the current service areas. Details on the number and exact locations for the new services are still under development. The same services now offered in the initial demonstrations areas will be offered statewide, where applicable.

Question:  Will the FAA continue to cover the cost of avionics to aircraft owners in Alaska as part of the statewide expansion?

Answer:  Capstone is actively exploring several options, in partnership with the Alaskan community that might help subsidize aircraft owners for the cost of Capstone avionics. However, it is not currently envisioned that the FAA will directly pay for the avionics as was done with the initial demonstrations.

Question:  Will non-installed, portable or hand held MFDs work with the Capstone system?

Answer:  Capstone is trying to ensure that low cost avionic displays are an option for users and has funded research at UAA to help the development of low-cost avionics that are compatible with the Capstone system. It is now expected that the avionics community will drive the development and sales of such devices to the users.

Question:  What manufacturers will offer UAT systems when Capstone III gets underway?

Answer:  Currently there is only one manufacturer of the UAT, Garmin. However, there are several other manufactures showing interest in developing and selling UATS. Capstone will be initiating discussions with avionics manufacturers to better understand their plans and schedules.

Question:  Will 1090ES ADS-B technology be available as part of the statewide expansion?

Answer:  Yes, the plan includes the eventual deployment of 1090ES in Alaska in parallel to the UAT infrastructure. The 1090ES ground stations will be developed as part of the National ADS-B program. Current estimates are that 1090ES ground stations would be available in the 2010-2012 time frame. Please note that FIS-B services will not be available on the 1090ES system.

Updated: 1:07 pm ET March 26, 2008