I have completely forgot to tell you about my Lift Reserve
Indicator project.
For reasons that we don’t need to repeat I have gained a particular
interest in the stall point at landing...
A traditional angle of attack meter is complex and
expensive (and feels like overkill for an ultralight aircraft) but I found a
number of articles on the web talking about “Lift Reserve Indicator” (here is one, here is another, and you will find many others as well as "for and against discussions" doing a simple search…).
While producing very much the same information as a traditional AOA indicator it is just a
differential pressure gauge connected to a probe with forward and aft
ports - and therefore at a fraction of the price and easy to do yourself...
The probe is an aluminum bar, (1 cm by 2 cm) as long I
could drill (some 13 centimeters). It is mounted approximately at ~20% of the wing chord counted
from the leading edge and leaning forward. The angle need to be refined in test
flights to confirm the correct reading.
If it works? I don’t know... but be sure I will tell you about
it here once I have tested it in flight…
How Much does it cost?
ReplyDeleteHi Giuseppe!
ReplyDeleteSorry for a late reply to your question. There is a link in the post to the Dwyer pressure gauge I got from Amazon, I just verified, the link is still working and says 44 USD. There are obviously other suppliers but that should give you an idea of the most expensive component. The aluminium bar I used to make the was about 5 euro and I still have most of it left. Some nylon tubing to connect the probe to the gauge, don't remember how much that cost but it is pretty cheap.
I'm still fine tuning my use of the LRI. It is an interesting instrument but I still find it difficult to stop flying by airspeed. Working on it...
Built the sensor using fibreglass resin surrounding two plastic straws. However unable to figure out how to remove the glass faceplate to modify the faceplate. Help or suggestion most appreciated. Thank you
ReplyDelete