Building an electronic Angle of Attack indicator

RST Engineering - JIm wrote:
Yes. It was made by National Semiconductor and you could get it linear or
logarithmic. It was obsoleted by National about fifteen years ago, but
there are still a few of them in the pipeline at a pretty hefty price.

Jim



wrote in message
...

Isn't there a voltage-to-LED-bar-graph IC? I seem to
remember such a thing. That would make the circuit simple.


Nope. It's still very much available in the surface mount package.

By God, you are correct. When my supplier told me in 1999 that the LM3914
was no longer available, they failed to tell me that the LM3914-1 was a
direct replacement and very much still in the pipeline, even as the larger
18 pin through-hole DIP package. Thanks for correcting me.

Jim


"Rip" wrote in message
...
RST Engineering - JIm wrote:
Yes. It was made by National Semiconductor and you could get it linear
or logarithmic. It was obsoleted by National about fifteen years ago,
but there are still a few of them in the pipeline at a pretty hefty
price.

Jim



wrote in message
...

Isn't there a voltage-to-LED-bar-graph IC? I seem to
remember such a thing. That would make the circuit simple.


Nope. It's still very much available in the surface mount package.

RST Engineering - JIm wrote:
By God, you are correct. When my supplier told me in 1999 that the LM3914
was no longer available, they failed to tell me that the LM3914-1 was a
direct replacement and very much still in the pipeline, even as the larger
18 pin through-hole DIP package. Thanks for correcting me.

Jim


"Rip" wrote in message
...
RST Engineering - JIm wrote:
Yes. It was made by National Semiconductor and you could get it linear
or logarithmic. It was obsoleted by National about fifteen years ago,
but there are still a few of them in the pipeline at a pretty hefty
price.

Jim



wrote in message
...

Isn't there a voltage-to-LED-bar-graph IC? I seem to
remember such a thing. That would make the circuit simple.

Nope. It's still very much available in the surface mount package.


My pleasure. This topic is timely, since I recently built myself a
"Lift Reserve Indicator" based on the LM3914 and a Honeywell sensor.
Now I'm doing a "true" angle of attack indicator based on the Maxim
4210 multiplier (and an op amp) to correct for airspeed ram pressure.

A terrific treatise on the subject (with one inconsequential math error)
can be found he
http://users.cablemo.net/~jjshultz/sonex/aoa.html

Rip

The electronics are trivial. The sensors are everything. Please post
detailed information.

Jim



"Rip" wrote in message
...


My pleasure. This topic is timely, since I recently built myself a
"Lift Reserve Indicator" based on the LM3914 and a Honeywell sensor.
Now I'm doing a "true" angle of attack indicator based on the Maxim
4210 multiplier (and an op amp) to correct for airspeed ram pressure.

A terrific treatise on the subject (with one inconsequential math error)
can be found he
http://users.cablemo.net/~jjshultz/sonex/aoa.html

Rip

RST Engineering - JIm wrote:
The electronics are trivial. The sensors are everything. Please post
detailed information.

Jim



"Rip" wrote in message
...


My pleasure. This topic is timely, since I recently built myself a
"Lift Reserve Indicator" based on the LM3914 and a Honeywell sensor.
Now I'm doing a "true" angle of attack indicator based on the Maxim
4210 multiplier (and an op amp) to correct for airspeed ram pressure.

A terrific treatise on the subject (with one inconsequential math error)
can be found he
http://users.cablemo.net/~jjshultz/sonex/aoa.html

Rip


I used a Honeywell ASDXL05D44D on my initial "lift reserve indicator",
mainly be cause I had a spare kicking around.

The true angle of attack design uses 2 Freescale MPXV7002 sensors.

The sensors really aren't that critical.You're after a repeatable
differential pressure signal, rather than absolute accuracy.

Rip wrote:
RST Engineering - JIm wrote:
The electronics are trivial. The sensors are everything. Please post
detailed information.

Jim



"Rip" wrote in message
...


My pleasure. This topic is timely, since I recently built myself a
"Lift Reserve Indicator" based on the LM3914 and a Honeywell sensor.
Now I'm doing a "true" angle of attack indicator based on the Maxim
4210 multiplier (and an op amp) to correct for airspeed ram pressure.

A terrific treatise on the subject (with one inconsequential math
error) can be found he
http://users.cablemo.net/~jjshultz/sonex/aoa.html

Rip


I used a Honeywell ASDXL05D44D on my initial "lift reserve indicator",
mainly be cause I had a spare kicking around.

The true angle of attack design uses 2 Freescale MPXV7002 sensors.

The sensors really aren't that critical.You're after a repeatable
differential pressure signal, rather than absolute accuracy.


I forget who makes it, but there's a commercially available system
that uses ports in the leading edge of a wing. My primary concern would
be how one protects from fouling while parked. I like your probe idea
since one could easily make a protective sleeve with a "remove before
flight" streamer attached.

Dan, U.S. Air Force, retired

On Sun, 10 May 2009 21:43:15 -0500, Dan wrote:




I forget who makes it, but there's a commercially available system
that uses ports in the leading edge of a wing. My primary concern would
be how one protects from fouling while parked. I like your probe idea
since one could easily make a protective sleeve with a "remove before
flight" streamer attached.

Dan, U.S. Air Force, retired


Any reason not to incorporate the LR sensor ports in a custom main
pitot pylon?

Dan wrote:
Rip wrote:
RST Engineering - JIm wrote:
The electronics are trivial. The sensors are everything. Please
post detailed information.

Jim



"Rip" wrote in message
...


My pleasure. This topic is timely, since I recently built myself a
"Lift Reserve Indicator" based on the LM3914 and a Honeywell sensor.
Now I'm doing a "true" angle of attack indicator based on the Maxim
4210 multiplier (and an op amp) to correct for airspeed ram pressure.

A terrific treatise on the subject (with one inconsequential math
error) can be found he
http://users.cablemo.net/~jjshultz/sonex/aoa.html

Rip


I used a Honeywell ASDXL05D44D on my initial "lift reserve indicator",
mainly be cause I had a spare kicking around.

The true angle of attack design uses 2 Freescale MPXV7002 sensors.

The sensors really aren't that critical.You're after a repeatable
differential pressure signal, rather than absolute accuracy.


I forget who makes it, but there's a commercially available system
that uses ports in the leading edge of a wing. My primary concern would
be how one protects from fouling while parked. I like your probe idea
since one could easily make a protective sleeve with a "remove before
flight" streamer attached.

Dan, U.S. Air Force, retired

Thanks Dan, but credit where it's due. The page I linked to is by Jeff
Shultz, who went through the same exercise I went through, and was kind
enough to make a web-page out of his research.