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Perrygraf/Imperial Oil Flight Computer

• Type: Circular Flight Computer
• Size: 4.5 inches / 12 cm
• Material: Card
• Scales:
• Front:
  • Course
  • Course Variation
  • True Airspeed or Wind Velocity
  • Index Angle
  • Drift Angle
  • Ground Speed
• Back:
  • DIstance or Fuel Consumption
  • Time
  • Temperature
  • Indicated Airspeed
  • True Airspeed
  • Pressure Altitude

Made by Perrygraf as an ad specialty item for a Canadian oil company. The unit lets you calculate drift angle and ground speed made good, fuel consumption and airspeed corrected for temperature. Probably not a terribly good substitute for an E6B, but we can all use a backup, right?