I would question indicated speeds in stalls for the wimple reason that stalls are normally at high angles of attack and most pitot static system get a little squirrelly at high angles of attack.
https://sites.google.com/site/mykr2stretch/ https://sites.google.com/site/mykr2stretch/parts-for-sale On Jun 25, 2014 9:54 PM, "Oscar Zuniga via KRnet" <krnet at list.krnet.org> wrote: > Mark wrote- > > >some of the stall speeds reported are clearly inaccurate > >indicated speeds, rather than GPS-verified speeds. > > Mark; please explain? I think you meant that many airspeed indicators > have not been verified by GPS or other means and are therefore not > accurately reading the airplane's airspeed. Otherwise, if I touch the > mains down at 55 MPH indicated but there's a direct headwind of 20 MPH, the > GPS will read a groundspeed of 35 MPH. Since the airplane is held aloft by > the relative wind flowing over the wings, indicated is what I want to know. > *Accurate* indicated, that is. Groundspeed will only be useful when there > is zero wind. > > I think it's also safe to say that just because the ASI reads accurately > in cruise is no assurance that it reads accurately all across its range. > Pitot-static errors can influence the reading depending on the geometry of > the system and other things, especially in slow flight, and instrument > error can vary depending on where in the airspeed range it's reading. I've > seen some light planes with ASIs that read up to 250 MPH, and I just don't > believe them when the needle is down below 50 MPH (if it even reads that > low). > > By the way, just curious- have you put the manometer to the ASI in > Niner-One-Juliet-Foxtrot to see how well it reads yet? > > Oscar Zuniga > Medford, OR > Air Camper NX41CC > A75 power > > > > _______________________________________________ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options >
