What is a good aspect ratio for an aircraft?

It depends on the mission. Sailplanes aim for AR 20–40 to minimize induced drag. Commercial airliners typically use AR 7–12 balancing lift efficiency and structural weight. Short-range fighters may use AR 2–4 for high-speed maneuverability.

Why does a higher aspect ratio reduce induced drag?

Induced drag arises from the wingtip vortices that form due to pressure differences between the upper and lower wing surfaces. A longer, narrower wing (high AR) has weaker tip effects relative to its span, so less energy is lost to vortices.

What is the Oswald span efficiency factor?

The Oswald efficiency factor (e) captures how closely a real wing matches the ideal elliptical lift distribution. A perfect elliptical wing has e = 1. Real wings typically range from 0.7 to 0.95. This tool estimates e using a common empirical formula based on aspect ratio.

What is the formula for aspect ratio?

AR = b² / S, where b is the full wingspan (tip to tip) and S is the reference wing area (planform). Equivalently, AR = b / c̄g where c̄g = S / b is the standard mean chord.

Does wing sweep affect aspect ratio?

Geometric aspect ratio is calculated from projected span and area regardless of sweep. However, sweep does affect the effective aerodynamic efficiency and stall characteristics, so engineers sometimes use an effective AR corrected for sweep angle.

Wing Aspect Ratio Calculator

Enter wingspan and wing area to instantly calculate aspect ratio, span efficiency, and induced drag metrics for any aircraft wing.

Wing Parameters

Unit System

Wingspan (b) — meters (m)

Total tip-to-tip span

Wing Area (S) — square meters (m²)

Planform (projected) area

Lift Coefficient (C_L) — optional, for C_Di

Leave blank to skip induced drag estimate

Enter wingspan and wing area, then click Calculate.

Aspect Ratio

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— : 1

AR = b² / S = (wingspan)² ÷ wing area

Fighter (AR ≈ 3) Airliner (AR ≈ 10) Sailplane (AR ≈ 30)

Standard Mean Chord (c̄g)

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S / b

Span Efficiency (e)

—

Oswald factor (0–1)

Induced Drag C_Di

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Provide C_L to compute

Reference: Typical AR by Aircraft Type

Aircraft Type	Typical AR	Characteristic
Fighter jet	2 – 4	High speed, high maneuverability
General aviation	6 – 9	Balanced efficiency and structure
Commercial airliner	7 – 12	Fuel efficiency at cruise altitude
High-altitude UAV	12 – 20	Endurance and thin-air lift
Sailplane / glider	20 – 40	Minimum induced drag, max glide

Summary

Wing aspect ratio (AR) is one of the most important aerodynamic parameters in aircraft design. Defined as the square of the wingspan divided by the wing area (AR = b² / S), a higher AR reduces induced drag and improves glide performance — which is why sailplanes have long, slender wings. This calculator also estimates the Oswald span efficiency factor and induced drag coefficient to give designers a fuller picture of wing performance.

How it works

Enter the wing's total wingspan (tip to tip) in meters or feet.
Enter the total wing area (planform area) in square meters or square feet.
Select your preferred unit system (metric or imperial).
The tool computes aspect ratio AR = b² / S instantly.
Derived metrics — span efficiency and induced drag coefficient — are calculated using standard aerodynamic approximations.
Adjust inputs to compare different wing configurations side by side.

Use cases

Evaluating wing efficiency during early aircraft conceptual design.
Comparing commercial jet, sailplane, and drone wing configurations.
Teaching aerodynamics — illustrating the trade-off between span and drag.
Checking computed AR against historical data for similar aircraft types.
Preliminary sizing of UAV wings for endurance or range optimization.
Estimating induced drag at a given lift coefficient for flight performance analysis.

Frequently Asked Questions

Last updated: 2026-06-04 · Reviewed by Nham Vu