Classics FMC
 

Hi guys

Have a question regarding classics 73s.
What Air Data Computer, under normal conditions, feeds speed information to the FMC (single Fmc Configuration).

Thanks.
H.C

Both!

The FMC gets speed input from both ADCs and both IRSs. However the primary/preferred (variation in Boeing terminology) sources are the left ADC & IRS.

S&L

Harry Cane
 

Thanks for your answer Capt. Sandler, and here’s another related question.

How the Fmc will respond in case of slight difference in speed information between ADC 1 and ADC 2 due to a partially clogged pitot system affecting the preferred ADC (ADC 1).