AN/APN-122(V) RadarThe AN/APN-67 is a completely integrated navigational system which is particularly suited to such aircraft as the Lockheed WZ-2 used for airborne early-warning. Equipment of even greater significance is AN/APN-122(V). AN/APN-122(V) comprises the Doppler portion of the AN/APN- 67, tied in with an advanced ground speed computer with extended attitude coverage, to provide a lightweight demo purpose ground velocities indicated. The V in the designator and 122 V is significant so these symbolize “versatility”.
The electrical outputs of the AN/APN-122(V) are heading velocity, drift velocity, ground speed, and drift angles. The operational and physical characteristics of the AN/APN-122(V) provide a good feel for the nature of high-performance Doppler navigational set. The weight of the AN/APN-122(V) is approximately 125 pounds as it is used in aircraft operating to an altitude of 70,000 feet, substantial weight is approximately two cubic feet excluding the antenna which requires separate consideration.
The volume of the antenna depends somewhat on the particular installation generally the antenna must be assigned a volume of two to three feet. The radome aperture generally requires approximately three square feet of the underside of the aircraft. The antenna two-way beam, which is generally free degree although some aircraft are so diminutive that smaller antennas with larger bandwidth must be used at some sacrifice in navigational accuracy.
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The transmitter output used in the 70,000 per system is approximately 15 Watts. Less power is used in sets designed for lower maximum altitude. The nominal transmitter frequency is 13,300 megacycles this is the approved frequency for Doppler navigation effect. The power consumption of the 70,000 feet system is approximately 600 watts, lower altitude systems require less power. The ground speed coverage of the AN/APN-122(V) is 80 - 800 knots. However, other tens of one-speed ranges can be provided to meet the needs of either lower speed aircraft or supersonic vehicles. The drift angle coverage is zero to plus or minus 45 degrees, the altitude coverage of the AN/APN-122(V) is 0 to 70,000 feet. The AN/APN-122(V) measures ground speed with an error of less than 1 %, drift angle is measured with an error of less than 1/2 degree.
Next, let us examine the units which comply the AN/APN-122(V). The antenna units of the AN/APN-122(V) has been described as the Doppler signal from the antenna are fed to an audio amplifier. This amplifier assembly is transistorized to provide high reliability. The signal data converter processes the audio frequency signals from the amplifier assembly converting them to 400 cycles per second fold edges which are accurately proportional to the components of the aircraft velocity along the axis of the two antenna beam. The signal data converter automatically searches for and acquires the Doppler signal, after which it automatically places the Doppler signals with a very high degree of precision. This is the power supply for the transmitters, it's irresponsible organizations, rugged construction and an extremely stable output voltage having an almost non-existent ripple content. The ground speed computer of the APN 122V uses advanced electrical analog computing techniques its computing elements provide accurate ground speed data over a wide range of aircraft attitude. The visual output for the AN/APN-122(V) is ground speed and drift angle displayed on a 3-inch cockpit instrument with integral illumination.
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Now a point of special significance is that the AN/APN-122(V) may be interconnected with other equipment to provide more comprehensive systems suited to an almost unlimited variety of specific mission. For example, the AN/APN-122(V) has been combined with the AN/ASA-13 Navigational Computer Group manufactured by Loral, this combination is being used in the Lockheed P2V land base anti-submarine warfare aircraft. It is also being used in seaplane such as the Martin C-5M anti-submarine warfare aircraft and in anti-submarine hunter-killer works performed by the carrier task force leader the Grumman S2F tracker regarding usage it is important to note that the combination of the AN/APN-122(V) and the AN/APN-13 provides the signals required for accurate stabilization of search radar against promotion of the search aircraft and for accurate control of the stylus of a plotting board.
Now let us see the role played by the AN/APN-122(V) insiders and small attacks aircraft. The AN/APN-122(V) has been integrated with recently developed very lightweight navigational computers to provide a featherweight navigational system which is especially applicable to the Douglas A4-B Skyhawk and other attack or fighter type aircraft. This particular system is designated the AN/APN-126 radar navigation set.
Adaptability to available space in very small high-speed aircraft is demonstrated by the A4-D installation, For example, the maximum antenna aperture widths available is 7 inches, this unique installation was accomplished by employing separate long now and gonna assembly. The port beam is transmitted through the forward port radome and port beam echo energy received through an act radome. A light assembly is employed for the starboard beam. AN/APN-126 units provide the same performance as antennas of single unit construction with equivalent aperture area. Simplified cockpit instrumentation continuously provides visible navigational information which guides the pilot accurately and reliably throughout the flight. Large navigation errors due to errors in estimated wind speed and direction are completely eliminated.
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From takeoff, the AN/APN-146 radar navigation set this capable of accurately directing light attack aircraft to the target area. After the mission is accomplished, it accurately directs the pilots back to base. To continue with this story of adaptability here is another navigational computer group, the Air Force ASN-7 which can be combined the AN/APN-122(V) to provide a system for certain tactical missions. This is one example of how the Air Force could benefit from the use of the AN/APN-122(V) and associated equipment.
A final word about the AN/APN-122(V), the AN/APN-122(V) is being combined with certain inertial units provide a Doppler inertial system which is advantageous in aircraft such as the Grumman S2F carrier-based all-weather attack aircraft.
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Next, let us turn our attention to the Army's requirements for self-contained navigation. Ryan electronics division has developed an integrated self-contained navigational and flight instrumentation system or army aircraft like the AN/APN-67 and the AN/APN-122(V), this all-weather set utilizes continuous wave Doppler sensing techniques designated the model Ryan 120. It will play a major role in the Army's NAP of the earth concept and the other advanced tactics characterizing power modern army.
Ryan 120 ARTF (A-BH072)The model 120 is a complete integrated navigational system comprising a Doppler set navigational computers navigational and flight control displays a vertical reference and the heading reference. The Doppler portion of the model Ryan 120 provides ground speed and drift angle and is functionally similar to the AN/APN-122(V). The principal differences are that it operates over a lower portion of the speed spectrum and that it utilizes less transmitter power. The model Ryan 120 includes a pictorial display which continuously and automatically shows the ground position and ground tracks. In certain missions no other display is necessary.
A major unit of the model Ryan 120 indicates wind speed, wind direction and provide counter type displays of present position and destination. This unit shows ground track relative daring of the destination, course errors and distance to destination. It shows the pilot, the best course and shortest distance to his destination. The basic system is designed for fixed-wing aircraft applications. However, low-speed accessories may be added as required to provide for the very low speed and the hovering requirements of helicopters. In rotary wing aircraft, this hovering indicator is provided to displays heading speed, drift speed, and vertical speed. The model Ryan 120 provides the arming increased flexibility in combat areas and it eliminates the need for ground radio stations with their attendant cost and vulnerability to attack. While tests have demonstrated an accuracy capability of one to two percent of the distance travel.
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Finally, let us examine what has been done for the Navy, airships, and helicopters. The AN/APN Doppler 97 navigational set design for use in a helicopter. It utilizes four radar beams, weighs approximately thirty pounds and operates from zero to plus or minus 150 knots. On 1897, automatically and continuously displays the heading speed, the drift speed and the vertical speed of the helicopters. It embodies the most advanced transistorization and wiring techniques. Outputs are provided for a tie-in with automatic stabilization equipment to permit smooth and safe automatic transitions to a huddling condition. The AN/APN-97 permits sustained automatic hovering under conditions of poor visibility with better precision than can be accomplished by experienced pilots operating under the best of weather conditions. The AN/APN-97 is a vital link in the Navy's all-weather ASW helicopters instrumentation program. It is predicted.
Equipment for the airship is the AN/APN-125 is similar to the AN/APN-97 except that it uses larger antennas and higher transmitted power. In the interest of standardization, its components are derived from the AN/APN-97 and the AN/APN-122(V). The higher power and larger antennas are required to meet the operational altitude specified for airborne early warning area.
In addition to its applicability to the ASW Airship, the AN/APN-125 is also suitable for the anti-submarine warfare missions performed by airship. The initial research was served as the foundation for the present family of versatile CW’s Doppler automatic navigators were performed by the naval research laboratory Washington, this works involving major contributions to the field of radar and aerial navigation.
Again as early as 1933, Brian's Job was developed and crew equipment needing the fringe and operational and environmental requirements of military aircraft and to produce equipment representing the latest state of the art in manufacturing techniques.
With modern aircraft demanding accurate self-contained automatic navigation it's fortunate indeed that Ryan CW Doppler navigational sets are available based on years of experience and thousands of flight hours. These navigational sets provide the most advanced concept for present-day aerial navigation.
Light in weight, accurate, operationally reliable, versatile and easy to maintain. They also promised to help overcome the new and challenging problems of the space age. You will see these versatile equipment doing their job in the setting of speed record, in the recording of the Earth's magnetic field, in new missions over the ends of the earth, during army vertical envelopment operation, in hovering operation detects the lurking enemy below, during extensive anti-submarine operation, in aircraft screen fire perimeters against progressing things, in directing aircraft back to base, in low-level tactics and in vehicles blasting off into the unknown.