Reference for worksheet entry, performance planning, checklist screens, PDF export, and troubleshooting.
Mountain Worksheet is an iOS flight-planning helper for mountain operations. The app combines worksheet entry, airport data lookup, POH-based performance calculations, a checklist, reference notes, and PDF export for supported aircraft.
The app is available on the App Store for supported iPhone and iPad devices.
On first launch the app presents a full-screen disclaimer. You must accept it before using the app.
The disclaimer can appear again if its stored acceptance is reset or if the disclaimer version changes in the app.
The Worksheet screen is where you enter or fetch the flight inputs used by the rest of the app.
There are separate sections for departure airport, arrival airport, and cruise altitude. For each airport, the app supports airport code, elevation, altimeter setting, OAT in Celsius, and runway length.
Entering a 3- or 4-character airport code triggers an automatic fetch after a short delay. You can also tap Fetch manually.
The fetch uses AVWX data to fill station elevation, longest runway length, METAR altimeter, and METAR temperature. If the fetch fails, the app shows an inline error message under the airport section. Manual entry remains available even if the fetch is unavailable.
The app can fetch winds aloft data from NOAA for your cruise altitude. This information helps determine whether wind conditions are safe for mountain operations and supports planning for ground speed, time, climb performance, and aircraft capability.
The lower section shows pressure altitude and density altitude for departure, arrival, and enroute conditions. Enroute values use cruise altitude plus averaged departure and arrival altimeter and temperature data. The higher-elevation airport is tracked as the worst-case planning source.
The Performance screen uses worksheet inputs plus aircraft selection and weight to calculate POH-based performance values.
The top card shows the current conditions from the highest-elevation airport currently entered: OAT, field elevation, and pressure altitude. That same airport is used for warnings and service ceiling estimates.
If the entered weight is outside the supported range for the selected aircraft, the app shows a warning state and some weight-adjusted outputs are replaced with Weight! or No C172.
The app shows max-gross and actual-weight estimated rate-of-climb values for departure, enroute, and arrival. Enroute calculations use cruise altitude and an estimated temperature based on the higher airport plus a standard lapse rate.
The TOLD section is split by leg. Departure (Takeoff) uses departure airport conditions, while Arrival (Landing) uses arrival airport conditions. Displayed values include ground roll and distance over a 50-foot obstacle. Arrival values include the app's built-in 1.05 safety factor.
For supported flap settings, the app shows Vso, 1.2 x Vso, 1.4 x Vso, and a recommended entry airspeed.
The app warns when the selected aircraft is outside the available POH table limits for altitude or temperature.
From the Performance screen, tap the PDF button in the top-right corner.
The generated report includes current conditions, aircraft and weight summary, rate-of-climb data, takeoff and landing distances, canyon turn data, and maneuvering speed data.
The fixed mountain-flying checklist is split into three scrollable screens:
These are reference-only in the current app. Items are not interactive and are not stored as completed or incomplete.
The Notes screen contains a fixed reference list of operational notes and reminders. In debug builds it also shows disclaimer reset and debug controls.
The current app does not provide editable or persistent free-form notes.
The app validates worksheet inputs for common ranges and shows inline validation messaging where applicable.
No dataThis usually means one or more required worksheet inputs are missing for that leg, such as elevation, altimeter setting, or temperature.
Weight! or No C172This means the selected aircraft weight is outside the supported range used by the calculator.