On 8/18/2005 10:49, wrote:

Maule Driver wrote:
: As a recreational pilot of a simple IFR aircraft, I've recently
: discovered a great role for the T&B; staying on heading. After a few
: years of struggling to keep my non-AP equipped flivver on a MH, I've
: re-discovered what many must know. The T&B is the best instrument to go
: straight with. The AI gives you good info, and the heading gyro does
: too, but the best way to keep it all centered in my Maule is definitely
: the T&B. Especially in calm conditions.

I don't know if I'll agree with that. Once you dial in your wind correction
angle, the DG is the primary instrument for bank in straight-level flying.

Here's another way to think about this.

I've done what Maule Driver is talking about, and think of it rather
like using the VSI to assist in maintaining altitude. I use the VSI
to give me an indication that an altitude change is coming, and I need
to anticipate it and correct (the VSI doesn't react all that quickly,
but still...)

If I do this right, I never see the altitude change. Of course,
this doesn't change the fact that the altimeter is the primary pitch
instrument - it's just not the only pitch instrument.

So ... I do the same with the T&B giving me an indication that a turn
is coming, and I can anticipate it and react. The DG is still the final
authority as to whether or not you're heading in the right direction, but
I think it's better to keep it on the heading, rather than notice it's
not and having to correct (when the turbulence allows, of course ;-) )



When I was working on the instrument written, I tried to find easy ways to
remember primary vs supporting instruments for different stages of flight. One of my
conclusions was that for long-term accuracy, the instruments that provide the integral
of the chosen parameter are the most accurate, and thus "primary." For instance,
the result of a pitch change integrated gives you altitude, so it's primary for
straight-level. The result of a bank change integrated yields a heading, so the DG is
primary.

The trouble with direct-read indications is that they are not accurate enough
for long-term useage. The AI is good for radical attitude changes, but you cannot see
a 1/10 stdrad turn on either it or the T&B/TC. You *will* see it on the DG as the
numbers slows roll by.

Of course, to each their own. Just so long as you keep the shiny-side up!...


-Cory

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************



--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA