Which single tool is commonly used to ensure squareness during parachute panel assembly?

• A. Bench square or carpenter's square
• B. Ruler
• C. Edge markers
• D. Clamps to hold pieces

Answer: (A)

The main idea here is keeping corners perfectly square during panel assembly. In parachute panel work, every edge and seam must meet at true 90-degree angles so the canopy lays flat and the seams align when sewn and loaded. A bench square or carpenter's square provides a fixed, accurate 90-degree reference between its arms. You can lay the long arm along one edge and the short arm along the adjoining edge to verify that the corner is truly square, and you can use it to lay out true right angles on fabric or webbing as you position pieces. This is why it’s the best single tool for ensuring squareness.

Rulers measure length, not angle, so they don’t reliably verify a right angle. Edge markers simply indicate where an edge lies but don’t confirm the angle. Clamps hold pieces in place but don’t establish or check perpendicularity, so you’d still need a square to confirm squareness.