AF Form 4015: High Altitude Release Point (HARP) Guide

AF Form 4015: High Altitude Release Point (HARP) Guide – Air Force personnel involved in high-altitude airdrop operations rely on precise calculations to ensure mission success and safety. AF Form 4015, titled High Altitude Release Point Computation, is a critical tool for determining the High Altitude Release Point (HARP) for personnel and cargo drops conducted above 3,000 feet AGL.

What Is AF Form 4015?

AF Form 4015 is an official U.S. Air Force form used by navigators, Combat Systems Officers (CSOs), and aircrew to manually compute the release point for high-altitude airdrops. It builds on basic Computed Air Release Point (CARP) solutions by adding a third vector for high-velocity or free-fall phases typical in HALO (High Altitude Low Opening), HAHO (High Altitude High Opening), or high-velocity cargo drops.

Primary users include:

  • C-130, MC-130, and other special operations or airlift aircraft crews
  • Personnel conducting military free-fall operations
  • High-altitude cargo delivery teams using high-velocity parachutes

While modern MAJCOM-approved mission planning software (MPS) serves as the primary method, AF Form 4015 remains the approved manual backup using the MB-4 computer (whiz wheel). Aircrew must verify all computer-generated solutions.

Why High Altitude Release Point (HARP) Matters?

High-altitude airdrops minimize aircraft exposure to threats and allow parachutists or cargo to cover significant horizontal distances under canopy or during free fall. Accurate HARP computation accounts for:

  • Wind drift during free-fall and under canopy
  • Aircraft true airspeed and ground speed
  • Temperature, pressure altitude, and density effects
  • Actuation altitudes and stabilization
  • Terrain elevation at the drop zone (DZ)

Proper use of AF Form 4015 helps achieve pinpoint accuracy on the Point of Impact (PI), which is vital for combat effectiveness and safety.

Key Sections and Computations on AF Form 4015

The form guides users through structured steps, typically including:

  1. Drop Data Inputs — Drop altitude, terrain elevation, pressure altitude, temperature, indicated/true airspeed.
  2. Rate of Fall Calculations — Adjusted for temperature and altitude.
  3. Altitude Computations — Corrected drop altitude, actuation altitude, stabilization altitude.
  4. Wind Effect Vectors — Free-fall drift and deployed (under canopy) drift.
  5. Forward Travel and Timing — From release to impact.
  6. Final Release Point Offsets — Distances in meters or nautical miles from the desired PI.

Formulas on the sheet (and detailed in AFMAN 11-231) use standard conversions, with many relying on a factor of 1.94 for meter-based solutions. K-factors (specific to parachute type and jumper/load weight) are central to drift calculations.

Download the Official AF Form 4015 PDF Here:
https://static.e-publishing.af.mil/production/1/af_a3/form/af4015/af4015.pdf

  • AFMAN 11-231 — Aircrew Procedures (provides detailed HARP guidance and form completion instructions).
  • AF Form 4018 — Computed Air Release Point (CARP) Computation (for standard/low-altitude drops).
  • AF Form 4017 — Modified High Altitude Release Point Computations.
  • Aircraft-specific manuals (e.g., MC-130J, HC-130J, EC-130J) that reference these forms.

Best Practices for USAF Aircrew

  • Always cross-check software outputs with manual computations when possible.
  • Obtain accurate wind data at multiple altitudes.
  • Account for jumper/load weight when determining K-factors and rates of fall.
  • Verify Point of Impact elevation and actuation altitudes carefully.
  • Document all computations clearly for mission debrief and safety reviews.

Training and proficiency with AF Form 4015 ensure aircrew readiness when digital tools are unavailable or need validation.

Stay Current with Official Sources

Forms and procedures can be updated. Always reference the latest versions on the official Air Force e-Publishing website (e-Publishing.af.mil). Consult your MAJCOM, unit standards, and current AFMANs for specific guidance.

Keywords: AF Form 4015, High Altitude Release Point, HARP computation, HALO HAHO, CARP, Air Force airdrop procedures, military free fall, C-130 airdrop calculations.

This article is for informational purposes and does not replace official Air Force instructions or training.

For the most accurate and up-to-date information, download the form directly from the link above and review AFMAN 11-231 or your applicable aircraft operating manuals.