"Montblack" wrote in message ...
First time I've stumbled across one of these:

Lift Reserve Indicator

http://home.hiwaay.net/~sbuc/journal/liftreserve.htm
"One of the AOA systems that has been around the longest is the Lift Reserve Indicator. This unit was developed in the
1970's and has been offered in a couple of different variations since then. There is considerable controversy over
just what the LRI actually measures and how it operates, but when the price of the analog unit was recently reduced
substantially, it got my attention. Since the panel of 399SB is rather unconventional, I had included a small backup
airspeed indicator. However, the AI was never used since I rely on the RMI uEncoder for pitot info, so I decided to
replace the AI with the LRI since it could also serve as a backup airspeed indicator. The decision was easier since
the LRI would fit in the same space as the little AI and was in the pilot's angle of vision."

http://www.liftreserve.com/
Company website - InAir Instruments


Montblack

Interesting, delta P between two sources, one more or less pointing forward and one more or less pointing downward. I
suppose the indicator has a pressure diaphragm inside it linked to the needle...

I want an AOA indicator for the BD4 someday...

Hmmmmmm.......