Declare an Emergency early and often!

I was on an IFR training flight, with my instructor, from Cameron Park
airport to Chico and back... This flight took us right over Beale
AFB... On the way back, the engine started running really rough to the
point of near failure. Carb heat didn't resolve the problem, mixture
didn't resolve the problem, and everytime we applied power the engine
would choke and bog down even more. Obviously I took off the hood and
started going through the emergency procedures, with my instructor (we
went through them a couple of times).

We were directly above Beale AFB and 5000 feet... We were already
talking to ATC as this was a simulated IFR flight, and told them that
we were having engine problems and wanted to know if Beale was an
option. ATC came back and asked, "five sierra mike, would you like to
declare an emergency?". Our reply, "errr, umm, standby...". The
engine had not completely stopped, but certainly wasn't providing
enough power to attempt to go anywhere else, so after a few seconds of
"what should we do", we replied, "five sierra mike would like to
declare an emergency". ATC immediately contacted Beale tower and
informed them of our situation, came back and told us to switch to
Beale tower frequency. We swithed over to tower and circled to land
from 5000 feet, which seemed to take an eternity.

Our greeting on the taxi-way, just off the runway (flashing lights and
all), was as we would have expected, being only a year after 9-11, but
all-in-all, they were very understanding. We went into base-ops and
gave them our relative information, got a ride home from the FBO/owner
of the plane and never heard another word about it.

The experience was actually very positive! We never got hasseled by
the FAA and ATC was very helpful in the transition to an emergency
landing at a high profile AFB.

My point in sharing this experience and responding to your post is
that, like you said, it really was no big deal. If I had another
situation that warranted a possible emergency declaration, I wouldn't
even hesitate.

BTW - The cause of the engine failure, as I was informed, was
vapor-lock???

Best Regards,
Todd