Aircraft stress app

Aircraft Pavement / Subgrade Stress Calculator

Estimate vertical stress below aircraft main gear assemblies. In “Under Selected Tire” mode, the surface stress starts at tire pressure and generally decreases with depth. “Origin Between Gears” and “Custom X-Y” modes help visualize stress overlap between tires and gear assemblies.

Input Parameters

Aircraft

Gross Weight, lb

Main Gear Load Fraction

Tire Pressure, psi

Load Factor

Evaluation Mode

Selected Tire ID

Custom Eval X, ft

Custom Eval Y, ft

Min Depth, ft

Max Depth, ft

Depth Step, ft

Plan Grid Depth, ft

Plan Grid Half-Width, ft

Plan Grid Step, ft

Section Max Depth, ft

Section Depth Step, ft

Section Half-Width, ft

Section X Step, ft

Disk Resolution

API base URL: https://api.geotechhub.tech. This HTML calls the production API using the aircraft routes without the /api prefix.

Aircraft—

Load / Tire—

Surface Stress—

Tires Modeled—

Eval Point—

Engineering Method and Equations

Tire load: P_t = (W · f_m · LF) / N_t
Contact area: A_t = P_t / p_t
Equivalent radius: r_e = √(A_t / π)
Point-load Boussinesq stress: σ_z = 3Qz³ / [2π(r² + z²)^5/2]
Uniform tire pressure is approximated by summing small point loads over the circular contact area.

Under “Under Selected Tire”, the surface stress starts at tire pressure.
Under “Origin Between Gears”, stress may start lower at the surface and increase at shallow depth because of overlapping stress bulbs.
This is a preliminary screening tool and does not replace FAARFIELD, layered elastic analysis, FEA, or project-specific pavement design.