limit of trim = limit of travel?

On May 7, 2:52*am, wrote:
On May 6, 7:16 am, WingFlaps wrote:

On May 7, 12:49 am, Stealth Pilot
wrote:
this may surprise you but an elevator is never stalled in flight.

Incorrect, any flying surface can be stalled.

Cheers

* *Can be, but can't be under normal conditions. Ice will do it, as
could unlimited aerobatics, but the average FAR 23 airplane is
certified for neither. The key here involves what the airplane is
certified for, and the FAR 23 airplane meets the requirements of that
Part. You can postulate endlessly about decreased effectiveness of the
elevator with the tab deflected, but believe me, the engineers (and
some of the others lurking here) are way ahead of you on this and any
other item you care to mention.

Yes they lurk well.

If those engineers didn't take this
stuff into account the airplane simply wouldn't get certified and you
would never get a chance to fly it.

This has nothing to do with certification.

* * Rather than arguing from ignorance, you should find some good
books on aeronautical engineering and bone up on some basics first.


LOL!!!! Been there done that. What about you? I've only detected
deep insight in Bertie so far , but I'm comforted by the deep knowlege
that your lurkers must have.

Cheers

On May 6, 9:13 am, WingFlaps wrote:

If those engineers didn't take this

stuff into account the airplane simply wouldn't get certified and you
would never get a chance to fly it.

This has nothing to do with certification.

Oh, it doesn't? Then, tell me, what items DO have to do with
certification, if elevator effectiveness at any trim tab position
isn't one of them? Find and quote the references to support your
claim.

Dan

On May 7, 3:28*am, wrote:
On May 6, 9:13 am, WingFlaps wrote:

If those engineers didn't take this

stuff into account the airplane simply wouldn't get certified and you
would never get a chance to fly it.

This has nothing to do with certification.

* * * * *Oh, it doesn't? Then, tell me, what items DO have to do with
certification, if elevator effectiveness at any trim tab position
isn't one of them? Find and quote the references to support your
claim.


Dan, you keep trying to pick up the wrong end of the stick.
I'm not talking about certification. For example, in the FARs does it
describe how the stabilator chord changes with trim positions?
Certification results from practical demonstrations of plane handling
and flying not theoretical aeronautical discussions -or is that not
so?

Cheers

"WingFlaps" wrote in message
...
Dan, you keep trying to pick up the wrong end of the stick.
I'm not talking about certification. For example, in the FARs does it
describe how the stabilator chord changes with trim positions?
Certification results from practical demonstrations of plane handling
and flying not theoretical aeronautical discussions -or is that not
so?

Cheers

Please forgive my for seeming to nit pick, but...

How does one talk about presumed abnormalities in the operation of type
certified aircraft, within the certified parameters, and then appear to
separate that discussion from the engineering and testing which must have
resulted in the certification?

Peter
(Starving for enlightenment)

On May 6, 9:40 am, WingFlaps wrote:

Dan, you keep trying to pick up the wrong end of the stick.
I'm not talking about certification. For example, in the FARs does it
describe how the stabilator chord changes with trim positions?
Certification results from practical demonstrations of plane handling
and flying not theoretical aeronautical discussions -or is that not
so?

The FARs don't care how the chord changes. They don't care
how the engineer achieves the flying qualities and strength they
demand for certification. They just set certain parameters that must
be met, and the engineers design an airplane that complies with those
parameters.
If the trim tab damaged the effectiveness of the elevator so
that the control surface stalled, or lost authority to the point that
the parameters could not be met, certification would not take place.
Period. Your arguments are specious.
Neither the FAA nor any foreign national governing body is
going to get into the minutiae of design specifics. There's no time
and no need. Or did you want to pay more taxes and user fees and a
higher price to buy or rent an airplane, just to achieve through
endless detail what is already achieved through mandated performance
and strength limits?

Dan

On May 7, 6:01*am, wrote:
On May 6, 9:40 am, WingFlaps wrote:

Dan, you keep trying to pick up the wrong end of the stick.
I'm not talking about certification. For example, *in the FARs does it
describe how the stabilator chord changes with trim positions?
Certification results from practical demonstrations of plane handling
and flying not theoretical aeronautical discussions -or is that not
so?

* * * * * * The FARs don't care how the chord changes. They don't care
how the engineer achieves the flying qualities and strength they
demand for certification. They just set certain parameters that must
be met, and the engineers design an airplane that complies with those
parameters.
* * * *If the trim tab damaged the effectiveness of the elevator so
that the control surface stalled, or lost authority to the point that
the parameters could not be met, certification would not take place.
Period. Your arguments are specious.

There are lots of factors that may _promote_ a surface stall (e.g.
rivet heads) but that doesn't mean the surface is not going to do it's
jub well enough to let the plane fly and pass the certification test.
It's similar to the (better known) idea that rivet heads may promote
flow separation -but that does not mean that riveted planes can't pass
certification does it? Understanding the effect of the trim tab on
the elevator may prevent the mistake of thinking it ihas _no_ effect
on elevator performance. It may be a philosophical discussion but
that does not mean it's specious.

Cheers

On May 6, 2:15 pm, WingFlaps wrote:
Understanding the effect of the trim tab on
the elevator may prevent the mistake of thinking it ihas _no_ effect
on elevator performance. It may be a philosophical discussion but
that does not mean it's specious.

Oh, _well,_ then, let's just say that the trim tab deletes a
little of the elevator's effectiveness, but not enough to matter, and
leave it at that.

Dan

On May 7, 11:43*am, wrote:
On May 6, 2:15 pm, WingFlaps wrote:
*Understanding the effect of the trim tab on

the elevator may prevent the mistake of thinking it ihas _no_ effect
on elevator performance. *It may be a philosophical discussion but
that does not mean it's specious.

* * Oh, _well,_ then, let's just say that the trim tab deletes a
little of the elevator's effectiveness, but not enough to matter, and
leave it at that.


Yea, it may, under the conditions I specified. Yes, let's end this fun
discussion as there's not much left to be said.

Cheers