Determination of bank angle from speed and heading change per time period

"Grumman-581" wrote in message
news : On Tue, 09 Jan 2007 13:17:32 +0000, in
: 28, Bob Moore wrote:
: I think that you are going to have to work with TAS instead of GS, but
: Figure 2.29 on page 179 of Aerodynamics for Naval Aviators has a graph
: of all the factors involved.
:
: Yeah, to be perfectly accurate, I would need air speed and not ground
: speed in addition to wind angle corrections, but I was curious if I could
: get a good approximation of the bank angle from just what I'm getting from
: the GPS without having to add a considerably costlier device like an
: accelerometer / gyro with rs232 outputs... The Garmin 18 5Hz puck type GPS
: goes for around $150... A bit more than the 1Hz units that are typical for
: car navigation, but not entirely out of line for this project... The
: accelerometer / gyro systems that I've seen so far with rs232 outputs go
: for around $1K-$2K... I understand that there is some new work in
: accelerometers for PC-based pointing devices that have brought the prices
: down considerably compared to the previous devices like this:
:
: http://www.watson-gyro.com/products/...A_80_spec.html
:

Don't know why wind angle would be important. Have to assume a coordinated turn also - a rudder turn would yaw like
crazy but not necessarily result in a bank angle....

On Tue, 09 Jan 2007 02:58:02 -0600, Grumman-581
wrote:

Anyone know of a formula for determing the current bank angle, given the
current velocity and rate of change in heading over a particular period of
time? I was thinking of adding an artificial horizon to program that I'm
working on and figured that by taking the current velocity as reported by
the GPS and the change in heading as reported by the last two
course-over-ground measurements from the GPS, I should be able to
determine a close approximation of the actual bank angle... Of course,
this assumes that the current winds are ignored in addition to assuming a
coordinated turn... The current system that I am using only gets updates
at 1 Hz which might be a bit low, but I'm thinking of getting the Garmin
18 5 Hz unit which should be sufficiently fast in its update rate...

Sounds like a great project...

Provide a great deal of valuable "darn-near-real-time" info to a
pilot...and at a cost that wont break the bank.

Makes sense...therefore...
(do I even NEED to finish the comment?)

MORE POWER TO YA!

Let us know how it works out.

--Don Byrer

Don Byrer KJ5KB
Radar Tech & Smilin' Commercial Pilot Guy
Glider & CFI wannabe
kj5kb-at-hotmail.com

"I have slipped the surly bonds of earth; now if I can just land without bending the gear..."
"Watch out for those doves...smack-smack-smack-smack..."