TAS calculation

Viewing 2 posts - 1 through 2 (of 2 total)
  • Author
  • #30221

    What will be the TAS if cruising altitude is 39000ft, temperature is ISA +5 and CAS 200 kt?

    Anthony Foxcroft

    Hi Jonathan,

    Using the E6B or CRP5 I get a TAS of 380 knots. With a CX2 I get 381.6 knots. For both the “trick” to this question is the temperature as 39000 feet is above the tropopause in ISA so you should use a temperature of -51.5 and not -58 if you had forgotten about the tropopause.

Viewing 2 posts - 1 through 2 (of 2 total)
  • You must be logged in to reply to this topic.
Log in below to access your courses.
Forgot Password
Enter your email address or username and we’ll send you instructions to reset your password.