Standby Vacuum?

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.

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

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