A design bench for people who actually build π¨ kites. Pick a planform β diamond, delta, sled, box or rokkaku β then drag β its proportions directly on a to-scale drafting canvas and watch π the sail area, aspect ratio, all-up mass and wing loading solve themselves as you work. Every number π’ comes from real engineering: dynamic pressure rising with the square of wind speed, a flat-plate model for the sail, uniformly loaded beam maths for the spars.
The heart of it is the bridle solver. Drag β the tow point along the kite's spine and a two-sided balance βοΈ beam tips between LUFF and OVERFLY, through a gold band that marks the angles this planform is actually stable at. The settled angle of attack it lands on drives the design's whole usable wind range, so trim and flyability are one connected thing rather than two separate numbers π’. It hands you the bridle leg lengths and the tow-ring position in millimetres, ready to tie.
Around that sit the sheets you need before cutting anything: a spar sheet that checks deflection and bending stress against nine real materials and nests a cut list π into the stock you own; a sail sheet that lays panels onto a fabric roll and works out yardage, seams, hems and the sail mass that sets your minimum wind; a line sheet with break strength, safety factor and the wind at which your line reaches its working load. A polar wind window shows where the kite will actually sit in the sky and what it would take to move it. Enter today π's wind once and the whole fleet re-sorts into what flies and what doesn't.
There is also a stock room where you can optionally photograph a spar bundle or fabric roll so you can tell your 6 mm carbon from your 4 mm, an eighteen-symptom trim troubleshooter that stages the specific fix onto your design, twelve knots drawn as step-by-step diagrams, field checklists, a flight log π, and fourteen short lessons that each carry a live solver instead of just text. Everything runs on the device π±, and the app is honest about what it is: simplified engineering models to get a frame close before you cut, not certified aerodynamic data.
A design bench for people who actually build π¨ kites.