UH-60A UH-60L UH-60Q HH-60L Black Hawk Helicopter Avionics Maintenance Manual – TM 11-1520-237-23 Volume 1

Description

File Details

• Manual Type: Aviation Unit and Intermediate Maintenance Manual
• Document Number: TM 11-1520-237-23
• Date: 1 May 1999
• Volume: Volume 1 of 8
• Models Covered: UH-60A, UH-60L, UH-60Q, HH-60L
• Language: English
• Page Count: 748
• File Format: PDF

Chapters Covered

• Chapter 1: Introduction
• Chapter 2: Civil Navigation (AN/ARN-123(V)) Set
• Chapter 2A: Civil Navigation (AN/ARN-147(V)) Set NAV
• Chapter 3: LF/ADF (AN/ARN-89) Set
• Chapter 3A: LF/ADF (AN/ARN-149(V)) Set NAV
• Chapter 4: Doppler Navigation (AN/ASN-128) Set
• Chapter 4A: Doppler/GPS Navigation (AN/ASN-128B) Set
• Chapter 5: Gyromagnetic Compass (AN/ASN-43) Set
• Chapter 6: Attitude Indicating Set
• Chapter 7: Rate-of-Turn Indicating Unit
• Chapter 8: Command Instrument Set
• Chapter 9: HSI/VSI Mode Select Unit
• Chapter 10: Radar Altimeter (AN/APN-209) Set
• Chapter 11: Heads Up Display (AN/AVS-7) Set

What This Manual Covers

This UH-60A UH-60L UH-60Q HH-60L Black Hawk Helicopter Avionics Maintenance Manual – TM 11-1520-237-23 Volume 1 is the first volume of an eight-volume set that provides aviation unit and intermediate maintenance data for the avionics systems installed on these four Black Hawk helicopter models. Volume 1 focuses on general helicopter information, civil and military navigation sets, compass systems, attitude and rate-of-turn instruments, the Command Instrument Set (CIS), radar altimeter, and Heads Up Display (HUD).

The manual opens with an introduction that establishes the scope of the entire eight-volume publication, including serial number applicability across the UH-60A, UH-60L, UH-60Q, and HH-60L fleets. It explains how the volumes are organized, how to use the narrative troubleshooting tables, and the meaning of warnings, cautions, and notes. Equipment description and data for the helicopter itself are also presented, covering stations, waterlines, buttlines, work areas, antenna arrangement, and console layouts.

Civil Navigation Systems

Chapters 2 and 2A cover the Civil Navigation (AN/ARN-123(V)) and Civil Navigation (AN/ARN-147(V)) sets. These systems receive VOR, Localizer, Glide Slope, and Marker Beacon signals to provide visual and aural navigation information to the pilot and copilot. The manual includes detailed equipment descriptions, principles of operation, power distribution, and functional interfaces with the HSI/VSI mode select panels, Command Instrument Set, and Intercommunication Set. Fault isolation procedures guide technicians through setup, self-test, VOR, LOC, GS, and MB checks with expected results and corrective action tables.

LF/ADF Systems

Chapters 3 and 3A cover the LF/ADF (AN/ARN-89) and LF/ADF (AN/ARN-149(V)) automatic direction finder sets. These systems provide manual and automatic direction finding capability across the low frequency band. The manual describes the compass, loop, and antenna modes of operation, along with the radio receiver, control panel, loop antenna, sense antenna, and impedance matching amplifier. Troubleshooting tables address tune meter response, audio output, bearing pointer indication, and 180-degree test functions.

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Doppler and Doppler/GPS Navigation

Chapters 4 and 4A cover the Doppler Navigation (AN/ASN-128) and Doppler/GPS Navigation (AN/ASN-128B) sets. These systems determine helicopter velocity from Doppler frequency shift measurements and compute present position, bearing, time, and distance to destination. The manual details the receiver/transmitter-antenna (RTA), signal data converter (SDC), computer display unit (CDU), and GPS antenna. Extensive fault isolation procedures cover operational checks, built-in test equipment (BITE) codes, waypoint downloading, and system self-test.

Compass, Attitude, and Rate-of-Turn Instruments

Chapter 5 covers the Gyromagnetic Compass (AN/ASN-43) Set, including the directional gyro, compass set control, induction compass transmitter, and magnetic flux compensator. The manual provides slaved and free operating modes, compass compensation procedures on a compass rose, and detailed fault isolation for heading flags, annunciator response, and compass card movement. Chapter 6 covers the Attitude Indicating Set with pilot’s and copilot’s displacement gyros, vertical gyro selection, and leveling procedures. Chapter 7 covers the Rate-of-Turn Indicating Unit with pilot’s and copilot’s rate gyros, turn rate pointer response, and alternate gyro selection.

Command Instrument Set and Mode Select Unit

Chapter 8 covers the Command Instrument Set (CIS), an integrated navigation set that processes signals from navigation sets, the No. 1 VHF/FM radio, and flight instruments to produce steering commands. The manual describes heading, altitude hold, navigation, VOR, ILS, ILS approach, back course, low altitude hold, go-around, Doppler navigation, FM homing, turn rate, CRS HDG, VERT GYRO, No. 2 bearing, flag and validity signals, and self-test. Chapter 9 covers the HSI/VSI Mode Select Unit, including Doppler and Doppler/GPS modes, VOR/ILS, back course, FM homing, turn rate gyro select, course-heading select, vertical gyro select, No. 2 bearing pointer select, and CIS mode compare.

Radar Altimeter and Heads Up Display

Chapter 10 covers the Radar Altimeter (AN/APN-209) Set, a high-resolution pulse radar terrain-tracking system that provides visual height display and low/high altitude warning lamps. The manual includes operational checks, zero adjust procedures, antenna replacement, and fault isolation for OFF flags, altitude indication errors, and push-to-test response. Chapter 11 covers the Heads Up Display (AN/AVS-7) Set, which allows the pilot and copilot to monitor essential helicopter operations without looking down at the cockpit. The manual describes the signal data converter, converter control unit, display units, thermocouple amplifiers, and interfaces with the attitude indicating unit, AFCS, cargo hook, caution/advisory system, civil navigation, collective sticks, CIS, Doppler/GPS or Doppler navigation, fire detection, instrument display system, and radar altimeter. Extensive built-in-test, symbology programming, barometric altitude adjustment, and thermocouple procedures are provided.

Who This Manual Is For

This UH-60A UH-60L UH-60Q HH-60L Black Hawk Helicopter Avionics Maintenance Manual – TM 11-1520-237-23 Volume 1 is written for aviation unit and intermediate maintenance personnel, avionics technicians, field service representatives, and anyone responsible for troubleshooting, testing, repairing, or maintaining the navigation and command instrument systems on these Black Hawk helicopters. It is also a valuable reference for collectors, historians, and students of military aviation maintenance who want to understand how these avionics systems are designed and serviced.

Why This Manual Matters

Avionics systems on the UH-60 series are complex and tightly integrated. Correct fault isolation and maintenance procedures are essential for keeping these helicopters mission-capable. This manual provides the exact test equipment setup, signal flow, connector references, and corrective actions needed to diagnose and repair navigation, compass, attitude, radar altimeter, and HUD problems. Without the correct reference, technicians risk misdiagnosis, unnecessary component replacement, or unsafe conditions.

The UH-60A UH-60L UH-60Q HH-60L Black Hawk Helicopter Avionics Maintenance Manual – TM 11-1520-237-23 Volume 1 is the authoritative source for the avionics sets it covers. It includes detailed wiring schematics, block diagrams, location diagrams, pin filtered adapter checks, and step-by-step fault isolation tables that reference specific connector pins and wire numbers. This level of detail is not available in generic aircraft maintenance guides.

Instant PDF Delivery

This manual is delivered as an instant PDF download after payment. There is no shipping, no waiting for a physical book, and no risk of a damaged or lost package. You can view the manual on any device that reads PDF files, including computers, tablets, and smartphones. You can print individual pages or the entire manual for use in the hangar or on the flight line. The PDF format allows you to zoom in on wiring diagrams and schematics for clear viewing of connector numbers and pin assignments.

Whether you are performing scheduled maintenance, troubleshooting a navigation fault, replacing a gyro, compensating a compass, or programming a Heads Up Display, this UH-60A UH-60L UH-60Q HH-60L Black Hawk Helicopter Avionics Maintenance Manual – TM 11-1520-237-23 Volume 1 gives you the procedures and specifications you need. It is a practical, working reference that belongs in every Black Hawk avionics shop.