----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]----
Ed,
I think Don has brought up a good worry on
this one.
My airspeed used to say numbers in the
115-119 range but dang, I always had headwinds when compared to my flight
plan. I had headwinds going both ways in an out-and-back.
Turns out, my airspeed indicator was off
by about 15 mph. They do that when they get old. (It was one of the
more disappointing days of my Ercoupe ownership when I figured out the ASI was
so far off. Sorry if I’m doing that to you.)
I’ll concede that an Alon might
manage those speeds with their more nicely shaped canopy but don’t think
I’ve heard of any Ercoupe going those speeds with less than a 115 hp
engine.
You might want to go flight test and do an
airspeed indicator test.
Below is the airspeed calibration test
posted by
Ed Burkhead
http://edburkhead.com
ed -at-
edburkhead???.com (change
-at- to @ and remove "???")
From
To calculate the true airspeed of your
aircraft, fly three separate legs, in rotation, at headings that differ by 90
degrees. For example, fly north, then east, and then finally south. Any initial
heading will do, so long as the turns are 90 degrees and in the same direction.
>From your GPS unit, determine the ground speed on each leg. Then enter the data
into this calculator to find your true airspeed and actual wind speed. Assuming
your initial heading is correct, the wind direction will also be calculated.
and here is the web site: http://www.csgnetwork.com/tasgpscalc.html
It does not compensate for changes in wind speed or direction as you change
altitudes.
============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm
