Flat-Plate vs NACA 63A‑010 Airfoil Performance for Subsonic, Low‑Re Rocketry

Abstract

Flat-plate airfoils are widely used in rocketry for their strength and high manufacturability. However, at subsonic speeds, they incur higher drag from early flow separation and turbulence, leading to unfavorable costs and flight efficiency. Laminar airfoils would solve these issues by maintaining a favorable pressure gradient, thereby reducing drag. This project’s purpose is to determine the efficiency of the NACA 63A-010 laminar airfoil over flat-plate airfoils at subsonic speeds. A two-phase procedure was used to compare the two airfoil types at subsonic regimes. Twenty airfoils, including the flat-plate and NACA 63A-010, were tested using XFOIL’s 2D airfoil solver. Each airfoil was evaluated for drag, transition behavior, and stability metrics. The second phase of the procedure involved launching identical rockets, each flown twice, with the hexagonal flat-plate and NACA 63A-010 fins. Each carries a BlueRaven altimeter measuring velocity, altitude, and attitude, while an onboard camera assesses stability. Simulations strongly favored the 63A-010 airfoil over the hexagonal flat-plate airfoil, showing a 60-81% reduction in profile drag at Reynolds numbers below 1,100,000, attributable to a longer transition point and lower drag coefficient, while also demonstrating improved stability. Flight tests further backed the simulation with an improvement of 10% in peak altitude reached by the rocket using NACA 63A-010 airfoils. Despite the NACA 63A-010 airfoil’s complex geometry, additive manufacturing enables similar cost and structural performance for both airfoil types. Given its superior performance over hexagonal airfoils, the NACA 63A-010 is a strong candidate for subsonic amateur rocketry and rocket-assisted takeoffs.