DA Form 3501-1: Precision Approach Radar (GCA) Data – DA Form 3501-1, titled Precision Approach Radar (GCA) Data, is an official U.S. Army form used to record detailed technical data about Precision Approach Radar (PAR) systems, also known as Ground Controlled Approach (GCA) radar.
Released on October 1, 2019, by the Department of the Army, this one-page form supports Terminal Instrument Procedures (TERPS) development, radar site evaluations, and operational safety for military airfields. It captures critical radar installation parameters essential for safe precision approaches.
Download the official DA Form 3501-1 here: https://armypubs.army.mil/pub/eforms/DR_a/pdf/ARN19502_A3501_1_FINAL.pdf
Key Facts:
- Prescribing Publication: TC 3-04.15 (Air Traffic Control Facility Operations, Training, Maintenance, and Standardization), Appendix D.
- Purpose: Documents PAR/GCA data for TERPS packets, minimum vectoring altitudes, and airfield instrument procedures.
- Status: Active and current as of 2026; available as a fillable PDF from Army Publishing Directorate.
Importance of Precision Approach Radar (PAR/GCA) in US Army Operations
Precision Approach Radar provides pilots with real-time azimuth (course) and elevation (glidepath) guidance during instrument meteorological conditions (IMC). Unlike ILS, PAR relies on a controller verbally guiding the aircraft based on radar returns.
Benefits of PAR/GCA:
- Enables no-gyro approaches.
- Supports operations to low visibility minimums (often comparable to Category I ILS).
- Critical for tactical and fixed-base airfields where other precision systems may not be available.
DA Form 3501-1 ensures radar sites meet strict safety and performance standards by recording site-specific data used in procedure design and obstacle clearance evaluations.
Who Uses DA Form 3501-1?
- US Army Air Traffic Control (ATC) personnel.
- TERPS specialists and flight inspectors.
- Airfield operations and aviation safety officers.
- Units conducting radar site surveys or deploying tactical ATC systems (e.g., ATNAVICS, GCA-2020/PAR-2020).
The form is a key component of TERPS packets submitted for instrument procedure approval.
How to Fill Out DA Form 3501-1?
Detailed block-by-block instructions are in TC 3-04.15, Appendix D. The form collects data on radar location, coverage, safety limits, and site specifics.
Typical Sections Include:
- Radar site identification and location data.
- Azimuth and elevation antenna parameters.
- Coverage ranges (e.g., up to 20 NM for PAR).
- Glide path and course alignment details.
- Safety limit settings (e.g., cursors for obstruction clearance).
- Remarks for special conditions or certifications.
Best Practices:
- Use current survey data and theodolite measurements.
- Coordinate with maintenance technicians for equipment specifications.
- Ensure accuracy for TERPS compliance and obstacle documentation (often paired with DA Form 7870).
- Retain copies for facility records and distribute as required for aviation procedure publications.
Always reference the latest TC 3-04.15 for exact field explanations, as the form supports both fixed and tactical environments.
Relation to TERPS and Other DA Forms
DA Form 3501-1 is part of comprehensive TERPS documentation:
- DA Form 3501: GCA Operations Log.
- DA Form 3501-2: Flyability Check Evaluation.
- DA Form 7870: Minimum Vectoring Altitude Obstruction Documentation.
These forms together support safe radar vectoring, approach procedures, and Minimum Vectoring Altitude Charts (MVAC).
Download and Access Official Resources
- Official PDF: Army Publishing Directorate – DA Form 3501-1.
- Prescribing TC: TC 3-04.15 (available via armypubs.army.mil).
- Fillable versions are also hosted on authorized military form repositories for convenience.
Stay Compliant and Current
US Army ATC and aviation units must use the most recent version of DA Form 3501-1 and follow TC 3-04.15 guidance. Regular updates to radar data are required when equipment changes, sites are relocated, or new obstacles appear. Proper use of this form helps maintain the highest standards of flight safety for precision radar approaches across Army operations.
For questions on completion or integration into facility operations, consult your local ATC facility chief, TERPS specialist, or reference Army Publishing Directorate resources. Accurate documentation directly supports mission readiness and pilot safety.