Switch Climb view to Mach above FL180

Author: RISCfuture

SF50 Shared/Helpers/formatters.swift

@@ -11,6 +11,7 @@ extension FormatStyle where Self == FloatingPointFormatStyle<Double> {
   public static var rateOfClimb: Self { .number.rounded(increment: 1) }
   public static var gradient: Self { .number.rounded(increment: 1) }
   public static var speed: Self { .number.rounded(increment: 1) }
+  public static var mach: Self { .number.precision(.fractionLength(3)) }
   public static var temperature: Self { .number.rounded(increment: 1) }
   public static var airPressure: Self { .number.rounded(increment: 0.01) }
   public static var heading: Self { .number.rounded(increment: 1) }

SF50 Shared/Performance/ViewModel/ClimbPerformanceViewModel.swift

@@ -69,6 +69,29 @@ public final class ClimbPerformanceViewModel {
   public private(set) var climbRate: Value<Measurement<UnitSpeed>>
   public private(set) var climbGradient: Value<Measurement<UnitSlope>>
 
+  /// Approximates TAS from IAS using altitude (pressure ratio)
+  public var climbSpeedTAS: Value<Measurement<UnitSpeed>> {
+    climbSpeed.map { IAS, uncertainty in
+      let altFeet = altitude.converted(to: .feet).value
+      // TAS ≈ IAS / sqrt(σ), where σ ≈ (1 - altFeet/145442)^4.255876
+      let sigma = pow(1.0 - altFeet / 145442.0, 4.255876)
+      let TASMultiplier = 1.0 / sqrt(sigma)
+      let TAS = Measurement(value: IAS.value * TASMultiplier, unit: IAS.unit)
+      let uncert = uncertainty.map { Measurement(value: $0.value * TASMultiplier, unit: $0.unit) }
+      return (TAS, uncert)
+    }
+  }
+
+  /// Mach number for current climb speed
+  public var climbMach: Value<Double> {
+    climbSpeedTAS.flatMap { TAS in
+      let tempKelvin = OAT.converted(to: .kelvin).value
+      let speedOfSound = 38.967854 * sqrt(tempKelvin)
+      let TASKnots = TAS.converted(to: .knots).value
+      return .value(TASKnots / speedOfSound)
+    }
+  }
+
   // MARK: Private
 
   private var model: PerformanceModel?

SF50 TOLD/Localizable.xcstrings

@@ -12,6 +12,10 @@
       "comment" : "Label to display when a value is not available.",
       "isCommentAutoGenerated" : true
     },
+    "(%@)" : {
+      "comment" : "A small, secondary text label below the main climb speed display, showing the value of the secondary airspeed measurement.",
+      "isCommentAutoGenerated" : true
+    },
     "(turf)" : {
 
     },
@@ -650,6 +654,10 @@
       "comment" : "Label for \"Landing Weight\" column in the landing performance table.",
       "isCommentAutoGenerated" : true
     },
+    "M" : {
+      "comment" : "The letter \"M\" used in the Mach display.",
+      "isCommentAutoGenerated" : true
+    },
     "Meets G/A Req?" : {
       "comment" : "Header for the column in the landing performance table that indicates whether the landing meets the required go-around distance.",
       "isCommentAutoGenerated" : true

SF50 TOLD/Views/Performance/Climb/ClimbResultsView.swift

@@ -9,6 +9,10 @@ struct ClimbResultsView: View {
   @Default(.speedUnit)
   private var speedUnit
 
+  private var showMach: Bool {
+    performance.altitude.converted(to: .feet).value >= 18400
+  }
+
   var body: some View {
     Section {
       // Prominent climb speed display
@@ -17,14 +21,44 @@ struct ClimbResultsView: View {
           .font(.headline)
           .foregroundStyle(.secondary)
 
-        InterpolationView(
-          value: performance.climbSpeed,
-          displayValue: { speed in
-            Text(speed.converted(to: speedUnit), format: .speed)
-              .font(.system(size: 48, weight: .bold, design: .rounded))
+        if showMach {
+          // Mach display with secondary airspeed
+          InterpolationView(
+            value: performance.climbMach,
+            displayValue: { mach in
+              HStack(alignment: .firstTextBaseline, spacing: 4) {
+                Text("M")
+                  .font(.system(size: 48, weight: .light, design: .rounded))
+                Text(mach, format: .mach)
+                  .font(.system(size: 48, weight: .bold, design: .rounded))
+                  .padding(.trailing, 4)
+
+                // Secondary IAS display
+                if case .value(let speed) = performance.climbSpeed {
+                  Text(speed.converted(to: speedUnit), format: .speed)
+                    .font(.title3)
+                    .foregroundStyle(.secondary)
+                } else if case .valueWithUncertainty(let speed, _) = performance.climbSpeed {
+                  Text("(\(speed.converted(to: speedUnit), format: .speed))")
+                    .font(.title3)
+                    .foregroundStyle(.secondary)
+                }
+              }
+              .accessibilityElement(children: .combine)
               .accessibilityIdentifier("climbSpeedValue")
-          }
-        )
+            }
+          )
+        } else {
+          // Standard IAS display
+          InterpolationView(
+            value: performance.climbSpeed,
+            displayValue: { speed in
+              Text(speed.converted(to: speedUnit), format: .speed)
+                .font(.system(size: 48, weight: .bold, design: .rounded))
+                .accessibilityIdentifier("climbSpeedValue")
+            }
+          )
+        }
       }
       .frame(maxWidth: .infinity)
 
@@ -67,17 +101,43 @@ struct ClimbResultsView: View {
   }
 }
 
-#Preview {
+#Preview("Offscale Low") {
   PreviewView { preview in
+    // Set defaults BEFORE creating view model (it observes these)
+    Defaults[.takeoffFuel] = .init(value: 50, unit: .gallons)
+
     let performance = ClimbPerformanceViewModel(container: preview.container)
+    // Low fuel causes offscale low
+    performance.altitude = .init(value: 3000, unit: .feet)
+
+    return List { ClimbResultsView() }
+      .environment(performance)
+  }
+}
+
+#Preview("IAS Display") {
+  PreviewView { preview in
+    // Set defaults BEFORE creating view model (it observes these)
+    Defaults[.takeoffFuel] = .init(value: 180, unit: .gallons)
 
-    // Set realistic mid-climb conditions
-    // Need at least 150 gal fuel to reach min weight of 4500 lbs
-    // (3550 empty + 0 payload + 150 * 6.71 = 4556 lbs)
-    performance.fuel = .init(value: 180, unit: .gallons)
+    let performance = ClimbPerformanceViewModel(container: preview.container)
+    // Mid-altitude climb (below 18,400 ft) - shows IAS
     performance.altitude = .init(value: 10000, unit: .feet)
-    performance.ISADeviation = .init(value: 0, unit: .celsius)  // Standard ISA conditions
-    performance.iceProtection = false
+
+    return List { ClimbResultsView() }
+      .environment(performance)
+  }
+}
+
+#Preview("Mach Display") {
+  PreviewView { preview in
+    // Set defaults BEFORE creating view model (it observes these)
+    Defaults[.takeoffFuel] = .init(value: 180, unit: .gallons)
+
+    let performance = ClimbPerformanceViewModel(container: preview.container)
+    // High altitude climb (above 18,400 ft) - shows Mach
+    performance.altitude = .init(value: 25000, unit: .feet)
+    performance.ISADeviation = .init(value: -15, unit: .celsius)
 
     return List { ClimbResultsView() }
       .environment(performance)

SF50 TOLDUITests/SF50_TOLDUITests.swift

@@ -1225,16 +1225,23 @@ final class SF50_TOLDUITests: XCTestCase {
     )
     safetyFactorDryField.clearAndType("1.1", app: app)
 
-    // Dismiss keyboard if it's up
-    app.tap()
-    Thread.sleep(forTimeInterval: 0.3)
+    // Dismiss keyboard by tapping outside the text field
+    if !app.keyboards.isEmpty {
+      // Tap on the navigation bar area to dismiss keyboard without affecting navigation
+      app.navigationBars.firstMatch.tap()
+      Thread.sleep(forTimeInterval: 0.3)
+    }
 
-    // Return to Takeoff tab
-    app.tapTab("Takeoff")
+    // Return to Takeoff tab - wait for tab bar to be ready
+    let takeoffTabButton = app.tabBars.buttons["Takeoff"]
+    XCTAssertTrue(
+      takeoffTabButton.waitForExistence(timeout: 2),
+      "Takeoff tab button should exist in tab bar"
+    )
+    takeoffTabButton.tap()
     waitForNavigation()
 
     // Verify we're actually on the Takeoff tab by checking for tab bar selection
-    let takeoffTabButton = app.tabBars.buttons["Takeoff"]
     XCTAssertTrue(takeoffTabButton.isSelected, "Should be on Takeoff tab")
 
     // Give extra time for the tab to fully switch and recalculations to complete