Holdover Calculator
An aviation anti-icing holdover and allowance time advisor based on FAA and Transport Canada published guidance. Built for the pre-departure decision.
Questions, bug reports, feature requests, or feedback — any of it is welcome. The fastest way to reach support is by email.
You can also reach the same address from inside the app: tap the … menu in the top-right and choose Send Feedback / Get Help. The in-app version pre-fills your app version, iOS version, and device model so triage is faster.
If you're reporting an unexpected result, it helps a lot if you can include:
• The METAR you were working with (or the manual conditions you entered).
• The fluid type, concentration, and brand.
• The result you saw — and what you expected to see.
• Which regulator (FAA or Transport Canada) you have selected in Settings.
The in-app Help sheet (toolbar menu → Help) walks through the interview, the result view, and the timer. The Disclaimer sheet covers the legal scope of the app as an advisory aid only.