Thread
:
X-43A successful flight
View Single Post
#
6
April 4th 04, 10:59 PM
Doug \Woody\ and Erin Beal
external usenet poster
Posts: n/a
On 4/4/04 1:46 PM, in article
, "Tarver
Engineering" wrote:
"Doug "Woody" and Erin Beal" wrote in message
...
SNIP
Missed the front part of the conversation, John. What exactly did he say?
I made a claim WRT the break out force of the F/A-18 stick and monkey came
by to correct me.
I'm not sure what break-out force you're talking about. Granted, my only
experience with MECH is during FCF's, but when you motor the right engine
(no generators on line), the stabs just move--period. If there was any
sensation of a "break out" force, I'd down the jet for binding flight
controls.
The Mech flight control function isn't easily "eliminated" from the legacy
Hornet. It is still part of the FCF checklist, however and is checked on
A
and C FCF's. (I fly so few B's that I haven't a clue if it's on that
list.)
I don't personally find it very useful (my opinion only) which is, I
think,
why it WAS eliminated from the Super Hornet.
The Super Hornet exists in a much different electric airplane reliability
reality.
Electrically? Only because it's new. From what I understand, the FCC's
aren't all that different--2 of 'em, 2 channels each. Hydraulically, it's a
different story entirely though. My last talk with a Boeing engineer about
the issue yielded that the MECH system in the legacy Hornet (baby Hornet,
whatever) was so unused, that it was deemed unnecessary by the Program folks
for the Super Hornet (cost/weight savings).
Can you imagine the skew the F/A-18E's pilot reported defect rate
is doing to the entire system? The numbers are actual war operations, so
their is no time to play chinese fire drill to hide defects. The numbers
are nearly as unbelievable as FAA turning in two zero killed years since
1997. Applying the RPL Model really paid off for the Navy.
I don't think that the "pilot reported defects" in the legacy Hornet's
flight control system were ever "hidden." In fact, I've even seen HAZREPS
with the latest PROM 10.7. The reason the Super Hornet's numbers are better
are more than likely because the jet's new and there aren't many of them
yet.
I don't know what RPL is, but if you're saying that the Super Hornet's doing
well, I agree.
The biggest reason that legacy Hornet pilots end up in MECH is because they
somehow inadvertently drive themselves there (mostly with an engine shut
down on FCF's). This is an extremely rare occurrence though and is easily
reset.
In fact, I can only recall hearing of one Mech-Off-Off incident (i.e. down
to the stabs only for controlling the jet) in the F/A-18A-D, and the guy
flying it (USMC?) shelled out shortly after because of the resulting
oscillations.
It is a simple thing to just break the stick out and use the backup.
What does that mean? The DDI will give you a MECH ON caution, and the
tic-tac-toe board will be filled with X's, but there's no "break out"
associated with MECH. The airplane will either continue to be controllable
or it won't--depending on where you are in the flight envelope and how well
the system is working for you. In this guy's case, it wasn't.
--Woody
Doug \Woody\ and Erin Beal