Winter OPS vs Holdover Calculator

Winter OPS supports aviation professionals during winter operations with fast access to Holdover Time information, De-/Anti-Icing guidance and SNOWTAM decoding — all in one purpose-built application. Configure the relevant operational conditions, select the applied fluid and quickly determine the corresponding Holdover Time (HOT). Compare available fluids at a glance and monitor the remaining HOT with configurable warnings and notifications. HOLDOVER TIMES: - Access Holdover Time (HOT) information based on supported FAA and Transport Canada guidance - Configure weather condition and precipitation intensity - Select outside air temperature in °C or °F - Configure fluid type and fluid/water mixture - Compare HOT values for available fluids at a glance - Consider operational parameters including wing surface, flap setting, precipitation speed and rotation speed - Display HOT start and end times using UTC, device time or countdown - Degree-Specific Holdover Times (DSHOT) available where permitted by your operator procedures HOT MONITORING: Keep track of your remaining Holdover Time during winter operations. Configure individual warning levels for: - Initial Warning - Last Warning - HOT Expiry DE-/ANTI-ICING REFERENCE: Quickly access useful operational reference information including: - One-step and two-step application guidelines - Application guidance by fluid and temperature - Qualified fluid information - Weather definitions - De-Icing and Anti-Icing terminology and definitions SNOWTAM & WINTER WEATHER: - Decode SNOWTAM information using the Global Reporting Format (GRF) - Snow intensity and visibility decoder - Present complex winter operations information in a clear and structured format DESIGNED FOR AVIATION OPERATIONS: Winter OPS is designed for pilots, flight operations, dispatch, ground operations and De-/Anti-Icing personnel who need relevant winter operations information without navigating through multiple documents and tables. The interface is optimized for quick access to operational information and can be configured according to individual requirements. Additional features include: - Light and Dark Mode - Configurable notification settings - UTC and local device time support - De-/Anti-Icing information sharing with Operations - Portrait support on iPhone - Portrait and landscape support on iPad DATA & GUIDANCE: Winter OPS uses Holdover Time data and guidance published for aircraft ground De-/Anti-Icing operations, including FAA and Transport Canada information and relevant EASA guidance. Applicable data is provided through annual subscriptions. Operators must always verify that the applicable data, procedures and winter season are approved for their operation. IMPORTANT: A subscription is needed for either all Fluids or Generic Fluids, available through in App Purchase or the respective individual Applications available in the AppStore. Winter OPS is an operational reference and support tool. It does not replace operator procedures, aircraft manufacturer documentation, applicable regulations or the professional judgement and responsibility of flight and ground personnel. Local authority requirements, operator documentation and aircraft-specific procedures must always be followed.

Holdover Calculator is a pre-departure decision tool for pilots facing winter operations. It returns the applicable anti-icing holdover or allowance time from FAA or Transport Canada published guidance, based on the actual weather, the de/anti-icing fluid applied, and your aircraft configuration. DESIGNED FOR iOS 26 Built for iOS 26 and its Liquid Glass interface. The pilot answers a sequence of focused questions; the app shows the matching table cell, the published range, and a continuously interpolated estimate within that range. KEY FEATURES • Holdover and allowance times from the current FAA Holdover Time Guidelines and Transport Canada HOT Guidelines. • Live weather autofill via the NOAA Aviation Weather Center — closest METAR or any ICAO you search. • Manual entry always available when stations are out of range or you want to model conditions ahead. • All four fluid types (Type I through Type IV) with both generic-table and specific-brand selections. • Active Frost allowance and Ice Pellet allowance with a 90-minute takeoff-window tracker. • Chart Notes surfaced inline, with active conditions (cold-soaked wing, OAT thresholds, etc.) flagged so you see only the notes that matter right now. • App Estimated time — a continuous interpolation across OAT and precipitation intensity, shown alongside the FAA Recommended low end of every published range. • Countdown timer with Live Activity on the Lock Screen. Minutes and seconds below an hour; hours and minutes above. The wall-clock "Ends at" reference is always shown to the second. • Apple Watch companion for the crew member running the timer. • Cockpit Sync — share one running timer across the flight deck. Link two to four pilots' devices over a direct local Wi-Fi/Bluetooth connection; the captain approves every change, and the link re-establishes itself if a device drops out of range. No account, no internet, no server. • Readable on the ramp. Tap any advisory note — or any setting's description — to enlarge it in a comfortable card sized for reading-distance glasses. • Support & Feedback in one tap. Reach the developer from the menu — write a note and attach a screenshot; your report includes a summary of what you changed this session so issues get resolved faster. No account required. • FAA or Transport Canada as the global default, with per-calculation overrides. • Local or Zulu time display; 12- or 24-hour clock. PRE-DEPARTURE DECISION ONLY This app is an advisor. The pilot in command remains solely responsible for verifying that the selected time is appropriate for the actual conditions, fluid, and aircraft at the moment of departure. Always cross-reference the current published holdover tables. DATA SOURCES • FAA Holdover Time Guidelines (current revision) • Transport Canada Holdover Time Guidelines (current revision) • NOAA Aviation Weather Center (aviationweather.gov) for live METAR observations SUBSCRIPTION Holdover Calculator is an auto-renewable annual subscription, with a free trial for new subscribers. Pricing is shown in the app before you subscribe. • Payment is charged to your Apple ID at confirmation of purchase. • The subscription renews automatically unless cancelled at least 24 hours before the end of the current period. • Your account is charged for renewal within 24 hours before the period ends. • Manage or cancel anytime in your Apple ID account settings. • Any unused portion of a free trial is forfeited when you purchase a subscription. PRIVACY Location is requested only to identify the nearest weather station; your coordinates are sent solely to NOAA to run that query and are never stored or shared with us. No ads, no analytics, no tracking. Privacy Policy: https://kilolimallc.github.io/legal/holdover-calculator/privacy.html Terms of Use (EULA): https://kilolimallc.github.io/legal/holdover-calculator/terms.html Disclaimer: https://kilolimallc.github.io/legal/holdover-calculator/disclaimer.html