ADG / TDG Quick Reference — Tool Guide

Coming Soon AC 150/5300-13B CHG 1 · ALL GUIDES

The ADG / TDG Quick Reference is a three-tab lookup for the FAA design-group classifications that drive airport geometry: Aircraft Approach Category (AAC), Airplane Design Group (ADG), and Taxiway Design Group (TDG). Instead of paging through AC 150/5300-13B to confirm which group a design aircraft falls in and what that group requires, the reference puts each group's classification criteria next to the design dimensions it drives — with the group-driven values served live from AvPlot's standards engine rather than hardcoded in the page, and every figure stamped to the governing AC edition (AC 150/5300-13B Chg 1, 8/16/2024).

This tool is built and in pre-release; it will open from the home page when released. This guide documents the full workflow.

Who It's For & When to Use It

Airport planners who need a fast, defensible answer to "what group is this, and what does that group require." Reach for it when confirming the classification basis for a design report or ALP narrative, when checking how a change in critical aircraft moves the airport between design groups, or when you need the taxiway design dimensions and hold-line distances a given group drives — including how airport elevation changes the hold-line values. Because the ADG tab walks you through an approach-category group and an airport elevation before showing dimensions, it is also the quickest way to get an elevation-adjusted hold line without opening the full Runway Linework workspace.

How to Use It

The tool opens as a single panel with three tabs. Pick the classification you need; the ADG tab is a short guided flow because its dimensions are approach-category- and elevation-specific.

Choose a tab — AAC, ADG, or TDG. The page opens on ADG by default and remembers your last active tab between visits. AAC and TDG are static reference tables; ADG runs the guided flow below.
(ADG tab) Step 1 — Select Aircraft Approach Category Group. Pick AAC A / B (V_at < 121 kt) or AAC C / D / E (V_at ≥ 121 kt). There is no preselected default — until you choose, the panel prompts you to, because the design dimensions differ significantly between the two groups for the same design group.
(ADG tab) Step 2 — Enter Airport Elevation. Type the field elevation in ft MSL. The page applies the holding-position elevation footnotes and shows an inline note for which footnote governs your selected group, plus an amber flag when an adjustment is actually in effect at that elevation.
(ADG tab) Step 3 — Read the reference dimensions. One card per ADG (I–VI) shows the governing criterion (wingspan band or tail-height band, whichever is more restrictive) and the dimensions that group drives: RSA width, ROFA width, runway/taxiway centerline separation, and hold-line distance — the visibility-split values shown per tier (≥3/4 SM vs. <3/4 SM). A Logic line under each hold line spells out which footnote applied and the exact per-100-ft math at your elevation. Tap a card for the "Why ADG __?" criterion detail; tap again to collapse.
(TDG tab) Read the taxiway dimensions. One card per TDG (1A–6) shows the main gear width (MGW) and cockpit-to-main-gear (CMG) classification criteria and the taxiway/taxilane width, taxiway edge safety margin (TESM), and shoulder width that group drives, in feet and meters, with the four-engine shoulder note where it applies.
Copy or hand off. Use copy on any value or row, or Copy table for the whole tab — each payload carries its citation and the AC edition. From the ADG and TDG tabs, deep-link buttons carry the selected AAC group into Taxiway Separation Standards and RPZ Dimensions (as ?aac=A or ?aac=C).

Key Features

Three tabbed references in one panel. Separate AAC, ADG, and TDG views; your active tab, chosen AAC group, and entered elevation all persist between visits.
Guided ADG flow. A two-step prompt (approach-category group → airport elevation) precedes the dimension cards, so the values you read are always the ones for your critical aircraft and field elevation.
Tail-height criterion shown. Each ADG card states that the group is governed by the more restrictive of the wingspan band or the tail-height band (AC Table 3-1), with both bands displayed — not wingspan alone.
Elevation-adjusted hold lines with explained logic. Hold-line distances apply the AC's elevation footnotes from the standards engine; a Logic line names the footnote and shows the actual +1 ft per 100 ft arithmetic at your elevation, and the values split by approach visibility tier.
Decision-Engine vintage stamp. Every tab carries an "AC 150/5300-13B Chg 1 · 8/16/2024" chip so the regulatory basis of each figure is on the face of the result.
Copy affordances. Per-value and per-row copy buttons plus a Copy-table button per tab; every payload is citation-stamped and TDG/ADG tables copy as tab-delimited text for spreadsheets.
Deep-links in and out. The page accepts ?aac= (and ?elev=) to preload a group and elevation, and emits the selected AAC group to the Separation and RPZ tools so the chain stays consistent.
Citation discipline. Group-driven dimensions come from the standards engine (RDSM / Appendix G), not values baked into the page, and the page links the governing AC directly.

FAA References

AC 150/5300-13B Change 1, Airport Design (8/16/2024) — governing standard for every figure on the page.
AAC by approach speed — Aircraft Approach Category is set by the threshold crossing speed V_at at maximum certified landing weight: A < 91 kt, B 91–120 kt, C 121–140 kt, D 141–165 kt, E ≥ 166 kt.
ADG by wingspan and tail height (Table 3-1) — Airplane Design Group is the more restrictive of the wingspan band or the tail-height band; the design dimensions per group come from the Appendix G RDSM.
TDG classification (Table 1-4) — Taxiway Design Group is set by pure rectangular main gear width (MGW) and cockpit-to-main-gear (CMG) ranges. Change 1 removed the 2022 diagonal boundary tests; this tool uses the rectangular ranges only.
TDG taxiway dimensions (Table 4-2) — taxiway/taxilane width, taxiway edge safety margin (TESM), and shoulder width per TDG.
Holding-position elevation footnotes 7 and 8 — Footnote 8 (AAC A/B): +1 ft per 100 ft above sea level. Footnote 7 (AAC C/D/E): +1 ft per 100 ft above 5,100 ft MSL.

Limitations & Disclaimers

AvPlot is technical planning production support — accurate enough for design reports, planning studies, and ALP narratives. It is not a replacement for stamped engineering or construction documents. Verify all values against current FAA publications before use in official Airport Layout Plans or regulatory submittals.

This is a classification and standards reference — it reports group criteria and group-driven dimensions; it does not classify a specific aircraft for you. Start from the Aircraft Classification Library for aircraft-specific AAC/ADG/TDG.
The ADG dimensions are approach-category-specific: the values change with the AAC A/B vs. C/D/E selection in Step 1, so confirm the selected group matches your critical aircraft before citing a figure.
Hold-line elevation adjustments follow the AC's Footnotes 7 and 8 as applied by the standards engine; site-specific hold-line placement remains a design determination.
TDG classification uses the Change 1 rectangular MGW/CMG ranges. Tools or spreadsheets predating Change 1 may still apply the removed diagonal boundary tests — do not reconcile against those.

Related Tools

Aircraft Classification Library — look up the AAC, ADG, and TDG of a specific design aircraft, then bring its groups here (guide).
Taxiway Separation Standards — the separation standards the same design groups drive; the ADG and TDG tabs deep-link here with the selected AAC group (guide).
RPZ Dimensions — Runway Protection Zone dimensions; the ADG tab deep-links here carrying the AAC group (guide).
Taxiway Fillet Tool — TDG-driven fillet geometry as CAD-ready output (guide).

Tips & Best Practices

Set the AAC group from your critical aircraft. The ADG dimensions hinge on it — start in the Aircraft Classification Library, then carry the group here so the cards reflect the right approach category.
Enter the real field elevation early. The hold-line distances only adjust once an elevation is in; the Logic line shows you the exact added feet so the number is defensible in a narrative.
Read the visibility split. RSA, centerline separation, and hold lines can differ between ≥3/4 SM and <3/4 SM — cite the tier that matches the runway's approach.
Copy citation-stamped, not just numbers. The copy buttons embed the AC edition and footnote basis, which is what makes a value paste-ready into a design report.
Chain the tools. Use the deep-link buttons to move the selected AAC group into Separation and RPZ rather than re-entering it, keeping the whole geometry set on one basis.

Understanding the Runway Design Code — how AAC, ADG, and visibility combine into the RDC that drives these design groups.
What Changed in AC 150/5300-13B Change 1 — the August 2024 updates affecting ADG/TDG dimensions and tables.