I've noted that there are AoA probes that use two pressure ports on 45
degree faces. Such as:
http://www.cgmasi.com/aviation/index.html although this one is also a pitot
probe.

I've wondered if pressure ports on the top and bottom of the fuselage nose
where the nose contours are at about 45 degrees to the airstream wouldn't
give about the same pressure diferential that could be used to compute AoA.

Bill Daniels


"Brian" wrote in message
oups.com...

On my want to do list is to build a flap controller for my HP16T.

I have been using PIC Microprocessers and pressure sensors that could
easily be adapted to do this. My initial Idea was to install a drag
rake that the microprocesser would read the pressure difference from
and would adjust the flaps accordingly. Alternate ideas are to connect
directly the the Pitot/Static system or build an AoA Sensor. All are
pretty easy to do but good low pressure sensors are in about $100
range and so far my budget hasn't made it to that. I really hadn't
considered AoA sensors until reading this thread, That might be a
cheaper way of doing this.

Brian Case
HP16T N16VP.



On Jul 10, 11:25 am, Udo wrote:
Unfortunately we do not have A of A meter. I have come to the
conclusion that using the flight manual for specific flap setting and
speeds and wing loading is the way to go.
For example: At a gross of 800 lb and a flap setting of +20 the
optimum speed range is about 5-7 kt, about the same in a 45 deg. bank
with the needed extra speed added for that bank.
But in level cruise the minimum drag has a range from about 70 kt to
95 kt at zero flap and 800 lb gross. You will feel the aft loading
of the airfoil in climb at the Flap handle , but no load in cruise.
Due to friction this " flap handle feel", as an indicator is
unreliable and depending on the airfoil also misleading.
I can speak from practical experience. On my past projects I had to
calculate the speeds for each flap setting as well as wing loading
In case of that airfoil it had a very narrow speed range in each flap
setting to maximize performance but it comes at a cost of having to
pay attention to the flaps to get the most out of each setting.
Udo

On Jul 10, 11:49 am, "Ken Kochanski (KK)"
wrote: