What are the RSA dimensions for ADG III?

For runways serving Airplane Design Group III aircraft in approach categories C, D, or E, the Runway Safety Area is 500 ft wide and extends 1,000 ft beyond each runway end per FAA AC 150/5300-13B Appendix G. For approach categories A and B at ADG III, the RSA is 300 ft wide and extends 600 ft beyond each end. Smaller-aircraft runways use reduced dimensions, such as 120 ft wide for ADG I small aircraft.

What is the difference between RSA and ROFA?

The Runway Safety Area (RSA) is a graded surface that must support an aircraft that overruns, undershoots, or veers off the runway. The Runway Object Free Area (ROFA) is a larger area centered on the runway that must be clear of above-ground objects except those fixed by function; for ADG III the ROFA is 800 ft wide.

Where are RSA and ROFA standards defined?

In FAA AC 150/5300-13B, Airport Design (Appendix G and Table 3-1, Runway Design Standards Matrix). Exact RSA and ROFA dimensions vary by Airplane Design Group and approach visibility minimums.

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RSA / ROFA / ROFZ Reference

Runway Safety Area and Runway Object Free Area dimensions per AC 150/5300-13B Appendix G. Select a design group and visibility minimum; every value carries its citation.

48 combinations · App G · How to use this tool

Set from design aircraft

Approach CategoryAAC

Airplane Design GroupADG

Fleet class—

Applies to A/B · ADG I–II only — small-aircraft-exclusive runways use reduced standards.

Visibility minimumAPPROACH

► RSA / ROFA / ROFZ Dimensions awaiting selection

Surfaces

Asymmetric runway ends are runway-governing on width. These dimensions reflect a single approach condition. When the two ends differ, look up each end independently and apply the larger width across the full runway — RSA and ROFA are each one continuous surface. Length values remain end-specific.

Dimensions: AC 150/5300-13B Chg 1, Appendix G (Runway Design Standards Matrix, Tables G-1–G-12). RSA and ROFA lengths each anchor to the ASDA / LDA ends and the LDA threshold (App H Table H-1; TORA anchors only the departure RPZ, ¶3.13.1.2). ROFZ per AC 150/5300-13B §3.11.2 (Figs 3-20–3-23) — width varies by aircraft size and approach minimums (400 ft large aircraft; 300/250/120 ft small-aircraft runways), extending 200 ft beyond each runway end.

► Plan view — both ends RSA SOLID · ROFA DASHED · ROFZ DOTTED · SCALED TO FIT

Diagram renders with a complete selection

Runway RSA boundary ROFA boundary ROFZ boundary Both ends drawn with identical conditions · width continuous full-length

► Apply to declared distances OPTIONAL

Enter each runway end's declared distances to see exactly where RSA and ROFA boundaries fall for that end. RSA and ROFA each extend beyond the ASDA and LDA ends and prior to the LDA threshold (AC 150/5300-13B Chg 1, Appendix H Table H-1). With the physical runway length entered, each end also shows the standard requirement next to the Appendix H adjusted requirement — the reduction obtained by declaring distances shorter than the runway. End names and the second end are optional — a single set of values works exactly as before.

Optional — pre-fills published declared distances from FAA NASR.

Runway designation

—

END 2 AUTO · OPTIONAL

Physical runway length

End 1TORA · TODA · ASDA · LDA

TORA

TODA

ASDA

LDA

Displaced threshold

Approach has vertical guidance

End 2OPTIONAL

TORA

TODA

ASDA

LDA

Displaced threshold

Approach has vertical guidance

► Complete RSA / ROFA / ROFZ reference 48 COMBINATIONS · FILTERABLE · CLICK TO SELECT

AAC

ADG

Visibility

Showing 48 of 48 combinations

Current selection RSA ROFA

Group	Visibility	RSA W (ft)	RSA beyond (ft)	RSA prior (ft)	ROFA W (ft)	ROFA beyond (ft)	ROFA prior (ft)
Loading reference data…

Dimensions: AC 150/5300-13B Chg 1, Appendix G Tables G-1 through G-12. · Beyond = from ASDA / LDA end (RSA and ROFA — App H Table H-1). Prior = from LDA threshold. · Verify all values against current FAA publications before use in official Airport Layout Plans or regulatory submittals.

Reference notes DEFINITIONS · MEASUREMENT · ASYMMETRY

What are RSA and ROFA?READ · ~30s

The Runway Safety Area (RSA) is a defined surface surrounding the runway, prepared and suitable for reducing the risk of damage to aircraft in the event of undershoot, overshoot, or excursion. It is centered on the runway centerline and must be cleared, graded, and drained.

The Runway Object Free Area (ROFA) is a defined area centered on the runway that must remain clear of objects except those required for air navigation purposes. It is larger than the RSA and provides additional clearance for aircraft operations.

Key distinction

The RSA is a physical surface requirement (grading, drainage, obstacle-free). The ROFA is an object-clearance requirement. Both are centered on the runway centerline.

Measurement referencesASDA · LDA

Widths are full widths centered on the runway centerline — half-width (offset from CL) = width ÷ 2.

RSA and ROFA lengths beyond the end are each measured from the end of ASDA and the end of LDA, whichever reaches farther (AC 150/5300-13B Chg 1, App H Table H-1, ¶H.4.3, ¶H.5.1.2 — TORA anchors only the departure RPZ, ¶3.13.1.2). Length prior to threshold is measured from the LDA threshold; with no displaced threshold this equals the length prior to the physical runway end. Where a stopway exists, the beyond-end length is measured from the stopway end (¶H.2.1, App G footnote 9).

For AAC C/D/E aircraft, RSA and ROFA dimensions do not vary by ADG or visibility minimums — all C/D/E groups share RSA width 500 ft and ROFA width 800 ft. For ADG III and above, the prior-to-threshold value applies to approaches with vertical guidance.

Asymmetric runway endsWIDTH IS RUNWAY-GOVERNING

Where RSA lengths differ between the departure end and the approach end, both dimensions must be satisfied independently.

When the two runway ends have different visibility minimums or AAC/ADG requirements, compute each end independently — then apply the larger width across the full runway. RSA and ROFA are each one continuous surface; width is runway-governing while length values remain end-specific.