Building an electronic Angle of Attack indicator

Ed wrote:
On Mon, 11 May 2009 22:44:23 -0500, Brian Whatcott
wrote:

There is one central location that is not subject to prop blast,
exactly: - that's the nose cone of the prop.
Visualize a small hole set about an inch back from the front.
Use a local pressure sensor chip and a wireless transmitter.

The flow from off axis would module the air pressure slightly
one cycle per revolution, with amplitude in proportion to
AofA (maybe :-)

Brian W

The wiring might be a little tricky

A wireless chip to a fixed receiver chip is not a biggie. But getting
that sensor chip and transmitter chip inside the nose cone in dynamic
balance would be an issue, I reckon....

Brian W

It is not a biggie if price is no concern. However, if you are trying to
bring it to market it is cost prohibitive.

Jim



"Brian Whatcott" wrote in message
...


The wiring might be a little tricky

A wireless chip to a fixed receiver chip is not a biggie. But getting that
sensor chip and transmitter chip inside the nose cone in dynamic balance
would be an issue, I reckon....

Brian W

RST Engineering - JIm wrote:
It is not a biggie if price is no concern. However, if you are trying to
bring it to market it is cost prohibitive.

Jim



"Brian Whatcott" wrote in message
...


The wiring might be a little tricky
A wireless chip to a fixed receiver chip is not a biggie. But getting that
sensor chip and transmitter chip inside the nose cone in dynamic balance
would be an issue, I reckon....

Brian W



Beyond cost I wonder if such a system could be made rugged enough to
survive the sustained g forces.

I would assume the airflow over the spinner would cause near constant
pressure on all sides of the spinner due to centrifugal force. I have
nothing to back this up, but it just seems probable.

There's a lot to be said for simplicity. On F-4E there was a "yaw
string" to indicate yaw. All it consisted of was a length of 550 cord
(parachute cord) with one end attached just behind the radome. The pilot
could see the other end in flight. When it was centered in his view the
aircraft was not yawing. I suppose an enterprising person could install
a similar string mount on a boom mounted scale extending from the front
of the wing within view of the pilot and out of propeller blast. 550
cord is available in several colours if that's what one wishes to use.

Dan, U.S. Air Force, retired