6
$\begingroup$

I fly in a consumer PC flight simulator. Among my virtual fleet is a fairly faithfully-reproduced MD-83.

One fairly strange detail I noticed is that enabling engine sync (either on N1 or N2) in the overhead, while on the ramp, triggers not just the alert on the annunciator panel, but also the master caution light -- why is this? Engine sync isn't a particularly abnormal condition. Is this just an inaccuracy in the simulator?

$\endgroup$
3
  • 2
    $\begingroup$ Is this with gear down? The FCOM says "An ENG SYNC ON annunciation on the overhead panel will come on when landing gear handle is in the down position and the ENG SYNC selector is in N1 or N2 position." $\endgroup$
    – Bianfable
    Mar 10 '20 at 15:43
  • 1
    $\begingroup$ That'd probably be it, thanks @Bianfable! I was toggling the switch on the ramp, and it looks like warning doesn't get toggled in the air with gear up. $\endgroup$
    – verandaguy
    Mar 10 '20 at 15:46
  • 1
    $\begingroup$ I still don't know why the warning actually exists. The FCOM does not say. Presumably, it is bad to land with ENG SYNC on, but I'm not sure why, since it further says "The pilot can override the system at any time with throttles." $\endgroup$
    – Bianfable
    Mar 10 '20 at 15:54
8
$\begingroup$

AFAIK The reason you aren't supposed to take off/land with prop or engine sync on is because if the leader engine fails, the follower engine will reduce power to match it, and that is really not ideal, especially low and slow, a la V1 cut or failure on short final. Try it out- fail the leader engine just after V1 and see what happens!

$\endgroup$
1
  • 2
    $\begingroup$ Nice answer, and makes intuitive sense the way you explain it. Please come back often - we could use more folks with Mad Dog experience here! $\endgroup$
    – Ralph J
    Sep 22 '20 at 22:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.