How do I install the Takeoff Distance Determination skill?

Run npx skillmds@latest add ashfordeou/takeoff-distance-determination in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

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Which AI agents work with Takeoff Distance Determination?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Takeoff Distance Determination free to use?

Yes. Installing skills from SkillMD is free. This skill is licensed under Apache-2.

Who published Takeoff Distance Determination?

ashfordeOU (@ashfordeou) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Takeoff Distance Determination by ashfordeou

Name: Takeoff Distance Determination
Author: ashfordeOU

Takeoff Distance Determination

Use when you must determine the takeoff distance for a flight test: integrate the measured ground speed samples over the ground roll, add the rotation distance at the rotation speed, and close the airborne climb segment to the 35 ft obstacle height with the climb rate. Produces the ground roll distance, rotation distance, climb distance, and total takeoff distance that gate the takeoff field length assessment. Trigger: takeoff distance, ground roll, rotation speed, 35 ft obstacle, climb segment, flight test.

ashfordeOU Updated Sep 17, 2026

File contents

Takeoff Distance Determination (flight-test-operations/performance/takeoff-distance-determination)

Use when the task is takeoff distance determination for a flight test: ground roll integration from measured speed samples, rotation to liftoff, and the airborne climb to the obstacle height.

Domain quick reference

Measurement method per the FAR 25.113 / CS-25.113 takeoff distance definition: distance from brake release to the point 35 ft above the takeoff surface, split into the ground roll, the rotation leg, and the airborne climb segment. 35 ft = 10.668 m (TARGET_HEIGHT_M).
Speeds in m/s, times in s, distances in m. Ground roll distance integrates measured ground speed over time with the trapezoid rule: s = sum((v_i + v_{i+1}) / 2 * dt_i) over consecutive samples.
rotation_distance: s_rot = v_rot * t_rot, the constant-speed leg from rotation start to liftoff at the rotation speed.
climb_distance: s_air = v_liftoff * h_target / climb_rate, the time to the obstacle height at the climb rate flown at the liftoff speed.
takeoff_distance: total = ground roll + rotation + climb; takeoff_distance_from_profile chains all three legs from one measured (v, t) sample set.
Analytic check: samples (0,0), (25,10), (50,20) m/s,s integrate to a 500 m ground roll; v_rot = 50 m/s, t_rot = 2 s gives 100 m; climb at 5 m/s to 10.668 m gives 106.68 m; total 706.68 m.

Workflow

Collect the measured ground speed samples (v, t) from the ground roll of the takeoff run.
Integrate the samples with ground_roll_distance.
Add the rotation leg with rotation_distance at the rotation speed.
Close the airborne leg with climb_distance to the 35 ft obstacle height.
Combine the legs with takeoff_distance and gate the takeoff field length assessment on the total.

Pitfalls

Integrating speed over distance instead of time: the ground roll distance is the time integral of the measured ground speed.
Using a single speed sample: trapezoid integration needs at least two samples with strictly increasing time.
Adding the rotation leg at the liftoff speed: the rotation leg runs at the rotation speed, which is lower.
Forgetting the 35 ft obstacle: the takeoff distance is measured to the obstacle height, not to liftoff.
Mixing units: m/s and s give m; knots or ft/s need conversion before integration.
Reporting raw test-day distance as the result: measured takeoff distance is corrected to standard conditions before it is compared against the field length requirement.

Behavior contract (gate 3)

The takeoff distance logic is exercised by the gate 3 contract test: scripts/test_takeoff_distance_determination.py against scripts/takeoff_distance_determination_logic.py (stdlib unittest, offline). Run: python3 scripts/test_takeoff_distance_determination.py

Compliance

Standards referenced, not reproduced: FAR-25 (14 CFR Part 25) is US government work (public domain) and CS-25 is a free EASA download; takeoff distance determination follows the FAR 25.113 / CS-25.113 measurement method in summary form per standards-map.yaml.
compliance: STANDARDS-REF, gated: false.

---name: takeoff-distance-determinationdescription: Use when you must determine the takeoff distance for a flight test: integrate the measured ground speed samples over the ground roll, add the rotation distance at the rotation speed, and close the airborne climb segment to the 35 ft obstacle height with the climb rate. Produces the ground roll distance, rotation distance, climb distance, and total takeoff distance that gate the takeoff field length assessment. Trigger: takeoff distance, ground roll, rotation speed, 35 ft obstacle, climb segment, flight test.license: Apache-2.0---# Takeoff Distance Determination (flight-test-operations/performance/takeoff-distance-determination)Use when the task is takeoff distance determination for a flighttest: ground roll integration from measured speed samples, rotationto liftoff, and the airborne climb to the obstacle height.## Domain quick reference- Measurement method per the FAR 25.113 / CS-25.113 takeoff distance definition: distance from brake release to the point 35 ft above the takeoff surface, split into the ground roll, the rotation leg, and the airborne climb segment. 35 ft = 10.668 m (TARGET_HEIGHT_M).- Speeds in m/s, times in s, distances in m. Ground roll distance integrates measured ground speed over time with the trapezoid rule: s = sum((v_i + v_{i+1}) / 2 * dt_i) over consecutive samples.- rotation_distance: s_rot = v_rot * t_rot, the constant-speed leg from rotation start to liftoff at the rotation speed.- climb_distance: s_air = v_liftoff * h_target / climb_rate, the time to the obstacle height at the climb rate flown at the liftoff speed.- takeoff_distance: total = ground roll + rotation + climb; takeoff_distance_from_profile chains all three legs from one measured (v, t) sample set.- Analytic check: samples (0,0), (25,10), (50,20) m/s,s integrate to a 500 m ground roll; v_rot = 50 m/s, t_rot = 2 s gives 100 m; climb at 5 m/s to 10.668 m gives 106.68 m; total 706.68 m.## Workflow1. Collect the measured ground speed samples (v, t) from the ground roll of the takeoff run.2. Integrate the samples with ground_roll_distance.3. Add the rotation leg with rotation_distance at the rotation speed.4. Close the airborne leg with climb_distance to the 35 ft obstacle height.5. Combine the legs with takeoff_distance and gate the takeoff field length assessment on the total.## Pitfalls- Integrating speed over distance instead of time: the ground roll distance is the time integral of the measured ground speed.- Using a single speed sample: trapezoid integration needs at least two samples with strictly increasing time.- Adding the rotation leg at the liftoff speed: the rotation leg runs at the rotation speed, which is lower.- Forgetting the 35 ft obstacle: the takeoff distance is measured to the obstacle height, not to liftoff.- Mixing units: m/s and s give m; knots or ft/s need conversion before integration.- Reporting raw test-day distance as the result: measured takeoff distance is corrected to standard conditions before it is compared against the field length requirement.## Behavior contract (gate 3)The takeoff distance logic is exercised by the gate 3 contract test:scripts/test_takeoff_distance_determination.py againstscripts/takeoff_distance_determination_logic.py (stdlib unittest,offline). Run: `python3 scripts/test_takeoff_distance_determination.py`## Compliance- Standards referenced, not reproduced: FAR-25 (14 CFR Part 25) is US government work (public domain) and CS-25 is a free EASA download; takeoff distance determination follows the FAR 25.113 / CS-25.113 measurement method in summary form per standards-map.yaml.- compliance: STANDARDS-REF, gated: false.

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