Re: Honeywell KFC225 autopilot roll servo failure

[[email protected]]

In sci.electronics.design Peter > wrote:
>I've just had my 6th failure of the roll servo, since 2002.

"Doctor, it hurts when I do this."
"Then don't do that."

>Can anyone offer me any info

Try
http://www.rockwellcollins.com/products/cs/br/flight_controls/index.html
maybe?

Matt Roberds

[Brian Whatcott]

On Sat, 24 Sep 2005 01:37:37 GMT, wrote:

>In sci.electronics.design Peter > wrote:
>>I've just had my 6th failure of the roll servo, since 2002.
>
>"Doctor, it hurts when I do this."
>"Then don't do that."
>
>>Can anyone offer me any info
>
>Try
>http://www.rockwellcollins.com/products/cs/br/flight_controls/index.html
>maybe?
>
>Matt Roberds


Hmmm...RC try to be customer-responsive these days, but I CAN remember
when they upgraded the FMS 800 and the roll command (used to steer to
the desired track), was reversed from its previous polarity - made for
interesting waypoint/turn capturing!

Brian W.

[Brian Whatcott]

On Sat, 24 Sep 2005 07:06:20 +0100, Peter >
wrote:

>
wrote
>
>>Try
>>http://www.rockwellcollins.com/products/cs/br/flight_controls/index.html
>>maybe?
>
>Well, yes, I am sure if I went through the massive paperwork exercise
>and installed something like that, or S-TEC, it would work just fine.
>
>It has to be said that the KFC225 does a super job of controlling the
>aircraft, even in pretty bad turbulence. It just keeps packing up. I
>am on my 3rd main unit, too (the built-in altimeter and pitch gyro are
>prone to packing up)


Have you monitored bus voltage n transients? There is a role for a
high power series resistor in servo drives! :-)

Brian W

[Rich Grise]

On Sat, 24 Sep 2005 07:06:20 +0100, Peter wrote:

>
> wrote
>
>>Try
>>http://www.rockwellcollins.com/products/cs/br/flight_controls/index.html
>>maybe?
>
> Well, yes, I am sure if I went through the massive paperwork exercise
> and installed something like that, or S-TEC, it would work just fine.
>
> It has to be said that the KFC225 does a super job of controlling the
> aircraft, even in pretty bad turbulence. It just keeps packing up. I
> am on my 3rd main unit, too (the built-in altimeter and pitch gyro are
> prone to packing up)

Speaking of that, were you in on the thread about autopilots and
hijackers? Is it true that autopilots can land airplanes so precisely
that they had to introduce dither so that they didn't wear ruts into
the runways from all of the airplanes landing in the same spot?

Thanks,
Rich

[neil]

"Rich Grise" > wrote in message
...
> Speaking of that, were you in on the thread about autopilots and
> hijackers? Is it true that autopilots can land airplanes so precisely
> that they had to introduce dither so that they didn't wear ruts into
> the runways from all of the airplanes landing in the same spot?
> Thanks,
> Rich
I heard that the F14s now land so accurately on the carriers that the centre
arrester cable has to be replaced often, but the others show no signs of
wear ;)
at least that's what the man in the black helicopter said...

[Matt Barrow]

"neil" > wrote in message
.uk...
> "Rich Grise" > wrote in message
> ...
>> Speaking of that, were you in on the thread about autopilots and
>> hijackers? Is it true that autopilots can land airplanes so precisely
>> that they had to introduce dither so that they didn't wear ruts into
>> the runways from all of the airplanes landing in the same spot?
>> Thanks,
>> Rich
> I heard that the F14s now land so accurately on the carriers that the
> centre arrester cable has to be replaced often, but the others show no
> signs of wear ;)
> at least that's what the man in the black helicopter said...
Must have, seeing that the last F-14 was retired some years ago.

[Scott Skylane]

Matt Barrow wrote:


> Must have, seeing that the last F-14 was retired some years ago.
>
>
Matt, check out "Background" on this page:

http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=1100&ct=1

Happy Flying!
Scott Skylane

[[email protected]]

neil skrev:

> "Rich Grise" > wrote in message
> ...
> > Speaking of that, were you in on the thread about autopilots and
> > hijackers? Is it true that autopilots can land airplanes so precisely
> > that they had to introduce dither so that they didn't wear ruts into
> > the runways from all of the airplanes landing in the same spot?
> > Thanks,
> > Rich
> I heard that the F14s now land so accurately on the carriers that the centre
> arrester cable has to be replaced often, but the others show no signs of
> wear ;)
> at least that's what the man in the black helicopter said...

The pilot is graded for every landing and, I believe, needs to maintain
a
certain average if he wants to keep flying. They are surposed to hit
that
cable on a good landing so I'd assume they get pretty good at it ;)


-Lasse

[Matt Barrow]

"Scott Skylane" > wrote in message
...
> Matt Barrow wrote:
>
>
>> Must have, seeing that the last F-14 was retired some years ago.
> Matt, check out "Background" on this page:
>
> http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=1100&ct=1
>
Background
Current plan is to have Tomcats in service until mid-FY07. Tomcat squadrons
have already started to transition to the F/A-18 E/F Super Hornet aircraft,
and will continue to transition in a phased approach.

That WAS the PLAN, back a couple years ago when the article was written, but
I recall (for what that's worth) that the last one was retired (for carrier
operations?) and the advanced Hornet was accelerated into operations. Wasn't
that a thread here just a few weeks ago?


--
Matt

---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[Scott Skylane]

Matt Barrow wrote:

>
> That WAS the PLAN, back a couple years ago when the article was written, but
> I recall (for what that's worth) that the last one was retired (for carrier
> operations?) and the advanced Hornet was accelerated into operations. Wasn't
> that a thread here just a few weeks ago?
>
>

Matt,

See: http://makeashorterlink.com/?Q36E21BDB

It's the Google group archive of J. Honecks thread. His first post has
a link to an article that indicates the last F-14 squadron was just
deployed to the Gulf.

Happy Flying!
Scott Skylane

[Matt Barrow]

"Scott Skylane" > wrote in message
...
> Matt Barrow wrote:
>
>>
>> That WAS the PLAN, back a couple years ago when the article was written,
>> but I recall (for what that's worth) that the last one was retired (for
>> carrier operations?) and the advanced Hornet was accelerated into
>> operations. Wasn't that a thread here just a few weeks ago?
>>
>>
>
> Matt,
>
> See: http://makeashorterlink.com/?Q36E21BDB
>
> It's the Google group archive of J. Honecks thread. His first post has a
> link to an article that indicates the last F-14 squadron was just deployed
> to the Gulf.
>
I read Jay's post of "What an amazing run the F-14 has had. It will be
terribly sad not to see
them flying anymore.... ", but not the article. :~(

"The venerable F-14 Tomcat, a mainstay of naval aviation, Hollywood movies
and air show awe since the 1970s, will retire for good after a final combat
deployment, which began Thursday. "
....
"The Tomcats require between 40 and 60 hours of maintenance for every hour
in the air, LaBranche said. For the F/A-18s, it's more like 10 to 15."
-----------------------------------------------------------
When I was a Norfolk a few years back, (2001) they (F-14's) were already
decorating the static displays as "museum pieces".


--
Matt

---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

[[email protected]]

In sci.electronics.design Peter > wrote:
wrote
>>Try
>>http://www.rockwellcollins.com/products/cs/br/flight_controls/index.html
>>maybe?
>
>Well, yes, I am sure if I went through the massive paperwork exercise
>and installed something like that, or S-TEC, it would work just fine.

It might be a silly amount of paperwork, but then you'd more than likely
have a reliable autopilot. As it stands, you are getting warranty
replacements, but there is a time and hassle factor of getting them
swapped out. Somewhere there is a break-even point.

>It has to be said that the KFC225 does a super job of controlling the
>aircraft, even in pretty bad turbulence. It just keeps packing up. I
>am on my 3rd main unit, too (the built-in altimeter and pitch gyro are
>prone to packing up)

Have you checked out the rest of the electrical system on the aircraft?
Maybe there is some other problem that is burning this stuff out. This
might even involve hooking up some kind of data logger and flying around
for a while; some spikes might not show up in ground testing or on short
flights.

Matt Roberds

[[email protected]]

In sci.electronics.design Brian Whatcott > wrote:
>On Sat, 24 Sep 2005 01:37:37 GMT, wrote:
>>http://www.rockwellcollins.com/products/cs/br/flight_controls/index.html
>
>Hmmm...RC try to be customer-responsive these days, but I CAN remember
>when they upgraded the FMS 800 and the roll command (used to steer to
>the desired track), was reversed from its previous polarity - made for
>interesting waypoint/turn capturing!

I based my suggestion on a few different observations. I used to work
at a flight simulator company and it was a lot easier to make the
Collins radios work right than the King ones. At that job, and since
then, I have also noticed that the "cheap" avionics package often
involves King radios, while the "upgrade" packages involve Collins
radios. Finally, I went on a job interview with Collins in 1996 and was
totally impressed by the amount of shiny! stuff at the plant in Cedar
Rapids. (Got an offer, too, but chose another offer in Dallas over
Cedar Rapids. Probably should have picked Cedar Rapids.)

Matt Roberds

[Brian Whatcott]

On Mon, 26 Sep 2005 07:13:17 GMT, wrote:

>///. I used to work
>at a flight simulator company and it was a lot easier to make the
>Collins radios work right than the King ones.
///
>Matt Roberds


Hmmm.... radios are one of the items where simulators invariably use a
front panel mock-up with switches and pots signaling the host.
They are not designed or provided by the avionics makers.
Making a mock-up work doesn't have much relation to the
avionics OEM, seems to me??

Brian W

[[email protected]]

In sci.electronics.design Brian Whatcott > wrote:
>On Mon, 26 Sep 2005 07:13:17 GMT, wrote:
>>I used to work at a flight simulator company and it was a lot easier
>>to make the Collins radios work right than the King ones.
>
>Hmmm.... radios are one of the items where simulators invariably use a
>front panel mock-up with switches and pots signaling the host.

Not always. Many of the radios I worked with (business jet and up) were
the kind where there was just a control head in the panel and the actual
guts (tuner, etc) were someplace else. We used the real control heads
and just dispensed with the remote guts. For the Collins radios, you
could read the spec, set up the control and data lines to the control
head, and get it right fairly quickly. For the King radios, reading the
spec was only the first step of a long journey into undocumented
goofiness. This pattern repeated itself with other hardware where we
used the actual aircraft item complete, such as a FMS.

Matt Roberds