Walkthroughs - Four guided tours now show how the app is used: - Holdover Times — setting the conditions and reading the time - Application Guidelines — reading the guidelines for a procedure and a temperature - SNOWTAM Decoder — entering and reading the reports for several runways - Snow Visibility — snowfall intensity from visibility Each runs on its own example and changes nothing you have set. They are in Settings → Help and can be repeated at any time. Snowfall rate The Holdover page now explains the precipitation rate behind the selected intensity — tap Rate above the arrows. When the outside air temperature is below the selected fluid's lowest operational use temperature, the readout now names that limit rather than only stating that no holdover time exists. DSHOT values SAE Type II, ABC-K PLUS and FCY-2 now correctly show the light/moderate precipitation intensity. Settings - Several settings now say what they decide, and the pages they sit on are easier to work through. Design improvements and minor bug fixes throughout.

Winter OPS has been redesigned and improved for the next generation of winter operations: - Updated to the newest Holdver Time Guidlines for Winter 26/27 - Redesigned interface for a cleaner and more intuitive experience - Improved performance, stability and reliability Thank you for using Winter OPS.

- Updated to the newest Holdover Time Guidelines for Winter 2025-2026. - Several Fluids have been added and removed. See full list in the update news. - Fluids applicable for allowance time have been specified by the authorities and several fluids were removed, as they were not validated at the time of the publishing of the new guidelines. - Review of the Transport Canada Snowfall intensity decoder - Several Improvements of the handling in the application (Weather selection and Snowfall intensity decoder) - Fixed an Issue with iPads and unjustified fluid warning

- Updated to the newest Holdover Time Guidelines for Winter 2025-2026. - Several Fluids have been added and removed. See full list in the update news. - Fluids applicable for allowance time have been specified by the authorities and several fluids were removed, as they were not validated at the time of the publishing of the new guidelines. - Review of the Transport Canada Snowfall intensity decoder - Several Improvements of the handling in the application (Weather selection and Snowfall intensity decoder)

The Moderate Freezing Drizzle Holdovertimes needed an adjustment to match the definition of the General Information for the Holdover Times. The changes have been performed for all Fluids generic SAE and specific.

Holdovertimes Updated Holdover Times for Winter Season 2024-2025 WinterOPS has been brought to the newest regulations FAA/EASA and TC. HOT and DSHOT Updates have been done. Fluid Changes Addition of fluid ALAB International PROFLIGHT PG4 Addition of fluid Chongqing Joba Chemical Co., Ltd FW-IV Addition of fluid MKS DevO Chemicals COREICEPHOB TYPE-IV PG Addition of fluid Shaanxi Cleanway Cleansurface IV Addition of fluid Chongqing Joba Chemical Co.,Ltd FW-I Addition of fluid Newave Aerochemical Co. Ltd. FCY-1Bio+ (R) Removal of fluid Clariant Safewing MP II FLIGHT PLUS Removal of fluid JSC RCP Nordix Defrost PG 2 Removal of fluid All Clear ClearWing ECO Removal of fluid Clariant Max Flight AVIA Removal of fluid Clariant Max Flight SNEG Removal of fluid Clariang Safewing EG IV NORTH Removal of fluid Beijing Wangye Aviation Chemical Product Co Ltd. KLA-1 Removal of fluid Clariant Produkte (Deutschland) GmbH Octaflo LYOD Removal of fluid Clariant Produkte (Deutschland) GmbH Safewing EG I 1996 (88) Removal of fluid Clariant Produkte (Deutschland) GmbH Safewing MP I 1938 ECO Removal of fluid Clariant Produkte (Deutschland) GmbH Safewing MP I 1938 ECO (80) Premix 55% i.g. ready-to-use Removal of fluid Cryotech Deicing Technology Polar Plus® Removal of fluid Gansu xiexin huineng Science and technology development Co., Ltd. XHN-1 Restructuring of Allowance Times (see details below) Snow mixed with Freezing Fog has received its dedicated column for each fluid. For detailed updates, please refer to the official regulatory documents. DSHOT DSHOT updates to the newest regulations FAA/EASA and TC DSHOT have been extended to Snow mixed with Freezing Fog Allowance Time The Allowance Times have been updated with new values The authorities introduced a list of applicable fluids for allowance times. Meaning, there will be no allowance times anymore for the generic fluids. New weather categories have been introduced (the MEATR Codes are included in the selection list) As the intensity is irrelevant for allowance times, the selection buttons are hidden, when an Allowance Time weather has been selected. Future Plans Restructuring of the Database for better performance Improvements in the weather conditions selection Thank you for using Winter OPS

- Updated Holdover Times for Winter Season 2023-2024 - WinterOPS has been brought to the newest regulations FAA and EASA. HOT and DSHOT Updates have been done. New Fluids - Addition of fluid Aero Mag 2000 SYR LLC DeiceX PG ADF Concentrate - Addition of fluid ALAB International PROFLIGHT EG1 - Addition of fluid Topan LLC TOPAN TYPE I - Addition of fluid Xinjiang Zhongtian Liyang Aviation Newmaterial Technology Co., Ltd Clearice-IB Removed fluids - Removal of fluid Kilfrost Limited Kilfrost DFSustain - Removal of fluid LNT Solutions LNT P188 - Removal of fluid Newave Aerochemical FCY-2 Bio+ - Removal of fluid Clariant Max Flight 04 - Removal of fluid JSC RCP Nordix Defrost EG 4 - Removal of fluid Shaanxi Cleanway Cleansurface IV - New weather category Snow mixed with Freezing Fog & ice pellets mixed with drizzle added - For detailed updates, please refer to the official regulatory documents. Decoders - New Global Reporting Format implemented into SNOWTAM Decoder - Small change to Snow Visibility notes

- Added Aircraft Performance Values in the Operations Settings. These are relevant to calculate the LOUT according to the Performance and Aerodynamic Acceptance Values in Tables 54 and following. New Middle Speed Values have been introduced for Fluid III (AeroClear MAX), all the other Fluids only have high and/or low speed Values. *If uncertain whether the aircraft to be treated conforms to the low speed, the middle speed, or the high speed aerodynamic test, consult the aircraft manufacturer. The aerodynamic test is defined in SAE AS5900 (latest version). - Default value is HighSpeed Aircraft Performance - The V Rotate Speeds are only used for allowance time calculations and are not used for the LOUT calculations anymore according to the new regulations. - Updated Snowfall Intensities Decoder to new regulations (now FAA, EASA and TC have been harmonized and all use the same values) - Bugfix in the Snowfall intensities Temperature Selection for Fahrenheit - Added Type I Fluids Sky-Go PG 80 & Safewing MP I LFD 80 Pre-Mix 55% - Added Type II Fluids Ice Clear II & COREICEPHOB Type II - Added Aeroclear Max values for Medium Speed Aircraft - Added new Weather Type of Ice Crystals mixed with Freezing Fog, Ice Crystals mixed with Freezing Mist and Snow mixed with Ice Crystals - 4.3.1 was not showing any Holdovertimes for SAE Types I, II, IV - this has been fixed now

- Added Aircraft Performance Values in the Operations Settings. These are relevant to calculate the LOUT according to the Performance and Aerodynamic Acceptance Values in Tables 54 and following. New Middle Speed Values have been introduced for Fluid III (AeroClear MAX), all the other Fluids only have high and/or low speed Values. *If uncertain whether the aircraft to be treated conforms to the low speed, the middle speed, or the high speed aerodynamic test, consult the aircraft manufacturer. The aerodynamic test is defined in SAE AS5900 (latest version). - Default value is HighSpeed Aircraft Performance - The V Rotate Speeds are only used for allowance time calculations and are not used for the LOUT calculations anymore according to the new regulations. - Updated Snowfall Intensities Decoder to new regulations (now FAA, EASA and TC have been harmonized and all use the same values) - Bugfix in the Snowfall intensities Temperature Selection for Fahrenheit - Added Type I Fluids Sky-Go PG 80 & Safewing MP I LFD 80 Pre-Mix 55% - Added Type II Fluids Ice Clear II & COREICEPHOB Type II - Added Aeroclear Max values for Medium Speed Aircraft - Added new Weather Type of Ice Crystals mixed with Freezing Fog, Ice Crystals mixed with Freezing Mist and Snow mixed with Ice Crystals

Initial Update for the 2022-23 Winter Season. Focus has been set on the update of Hold Over Times and DSHOTs. The new Fluids and Weather categories, as well as the SNOWTAM Converter will follow in the next few days.

Added degree-specific holdover times (DSHOT) The DSHOT database is an extension of the FAA and TC HOT Guidelines. The data it contains is derived from the same natural snow test data that is used to calculate the snow HOT values within the standard HOT tables. Within a typical HOT table, HOTs are provided for defined temperature ranges (e.g., -3°C to -8°C). The HOTs provided within a given temperature range are based on the coldest temperature of that range. Within the DSHOT database, specific HOT values are provided for each Type II, III, and IV fluid at all temperatures decrementing down to a given fluid's LOUT. A 1°C safeguard is incorporated in all DSHOT calculations The DSHOT take into place if the flaps were deployed at the time of deicing/anti-icing, provided the correct selection has been made in the HOT Screen. Any operator making use of the DSHOT data in a modified format shall employ a detailed verification process to ensure that the data presented is accurate and complete. This verification process shall consist of a series of manual checks of the DSHOT data within a DSHOT data presentation (e.g., a modified paper table or an eHOT app) against the corresponding values published in the most recent FAA DSHOT database publication. A record of the verification process shall be kept and maintained and this record shall clearly demonstrate that all DSHOT values within a data presentation have been verified. The verification process shall be updated and/or repeated on an annual basis (or whenever the DSHOT database or its data presentation is updated, whichever comes first). Due to this requirements, the DSHOTs must be actively enabled in the settings (Operations Page), where the user gets presented with the requirements and will be asked for an acknowledgement. If you need assistance in the verification process, please contact inquiries@mr-apps.ch and we'll gladly help.

• Updates for the 2021-2022 Guidelines for FAA/EASA and Transport Canada • 9 new fluids added according to the regulations • Major Changes in Allowance Times for Type IV fluids • New weather freezing mist added • The new degree-specific holdover times (DSHOT) will be added in the upcoming days • The new global reporting format for SNOWTAM will be introduced later this year • Minor Bugfix of unjustified warning message

• Updates for the 2021-2022 Guidelines for FAA/EASA and Transport Canada • 9 new fluids added according to the regulations • Major Changes in Allowance Times for Type IV fluids • New weather freezing mist added • Minor bug-fixes • The new degree-specific holdover times (DSHOT) will be added in the upcoming days • The new global reporting format for SNOWTAM will be introduced later this year

• Updates for the 2020-2021 Guidelines for FAA/EASA and Transport Canada • Major Changes in Transport Canada very light snow times and application guidelines • Introduced Snowfall intensities as a function of visibility converter • Minor bug-fixes

Added Application Guidelines for all Fluid Types and different scenarios (anti-icing or de-&anti-icing) and different temperature ranges.

Added search capability for fluids: - for "all fluids" Subscription in the Hold Over Time Tab - for all subscriptions in the Qualified Fluids Tab - search for Fluid Name or Fluid Manufacturer - refine search for specific fluid type only Minor Bug fixes

Added Transport Canada Holdover Times Some design & dark mode improvements

Holdovertimes for 2019-2020 Season are now available in the application. Transport Canada Regulations will be added in the next few days. Allowance Times for weather like ice pellets or small hail added. Completely rewritten the application to ensure stability and quality of the application.

• FAA Holdovertimes Winter 2018-2019 • EASA Holdovertimes Winter 2018-2019 (see desclaimer below) • Updated Fluid application guidelines • Updated qualified fluids, now with LOUT and viscosity details • Wingsurface selector added • Flapsetting selector added • Precipitation Speed selector added As there are no more AEA Anti-/De-icing guidelines, EASA has defined in the Safety Information Bulletin SIB 2017-11, that the FAA Holdover Time Guidelines are to be used. Due to the different structure of the FAA Holdovertime tables, the Holdovertime determination needed to be completely redesigned and the application guidelines needed a revision, which unfortunately took a lot of time developing and thorough testing. The FAA Holdovertimes sometimes differentiate between aluminium wingsurfaces and composite wingsurfaces. This selection has been added to the new version. Additionally the app can now differentiate if the flaps/slats are "in" during anti-icing or deployed only shortly before take/off or if the flaps/slats have already been deployed during anti-icing. For certain precipitations the FAA Holdovertime tables provide values for different precipitation speeds. For example "very light", "light" or "medium" Snowfall have two values for holdovertimes. A higher protection time for low precipitation speed and a lower protection time when high precipitation speed is present. The Holdovertimes for the Generic Fluids Types I, II, III and IV are available. Additionally the Qualified Fluids have been updated in the application and now show the tested Lowest Operational Use Temperatures and the lowest on-wing viscocity. The additional information on weather and de-icing are based on the former AEA guidelines. To further ensure yearly updates of the holdover times, the guidelines starting for winter 2019-2020 will be available through in-App purchase. There will be two packages, one for just the generic fluids and one for the specific fluids. Additionally the application will be redeveloped and designed to the newest iOS.

Updated to Winter 2016/2017 AEA Edition 31. Notifications fixed Minor Bugfixes last time iOS 8 is supported

Updated to Winter 2015/2016 AEA Edition 30. WinterOPS now supports iPhone 6 and iPhone 6+ Minor Bugfixes iOS 8 is now minimum requirement

- Updated to newest AEA Guidelines (29th Edition July 2014 for Winter 2014-2015) - Updated to iOS7 Design * New update is in progress for iOS8 and iPhone 6/6+ Features

• New Hold over Times according to the newest AEA Edition 28 from July 2013 • The current Documentation used & Version Identifier can be found in the Settings Tab • Bug Fixes (especially Badge Number on the home screen) (MOTNE de-coding will be included before the Northern Winter Season)

Version 2.0.1: • Bugfixes ------------------------------- Version 2.0: • SNOWTAM Decoding - Text or Picker Input Mode - Text Decoding - Selection of Approach Runway incl. adaption of Decoding Text - Archive (Sorted according Date or Airport) - Normal and Russian Break Coefficient (automatically selected) • iPhone 5 Support • Bugfixes The Application update has been built upon iOS 5.0, the use of updated Devices is suggested.

• SNOWTAM Decoding - Text or Picker Input Mode - Text Decoding - Selection of Approach Runway incl. adaption of Decoding Text - Archive (Sorted according Date or Airport) - Normal and Russian Break Coefficient (automatically selected) • iPhone 5 Support • Bugfixes The Application update has been built upon iOS 5.0, the use of updated Devices is suggested.