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#1
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No this is where you are quite wrong! There is pleanty of up elevator on the
trailing edge of the main wing.... the air going over the top is separating due to the high angle of attack and this makes the elevator ineffective, so the nose lowers slightly and the glider picks up airspeed and it resumes normal flight. "spektr" wrote in message ... Bravo. So you are flying a glider with insufficient up elevator to cause a stall equipped with an airspeed indicator that doesn't register well on the low end of the spectrum. All wings stall when their critical angle of attack is exceeded. In its most benign form a stall will be recognnized as a slight vertical oscillation without a discernable break. If you had more elevator authority, it would get into this flight mode. Its inability to do so indicates a lack of elevator authority at slow speed. Your airspeed indicator reading zero means you are flying at a speed less than the minimum required to move the needle. You are probablu using a run of the mill ASI for airplanes. Nothing wrong with that, it just means you are slower than the gauge can indicate. You might consider an ASI for helicopters, they are much more sensitive at the lower end of the spectrum and will probably give you a better indication of whats going on. If you want to make your glider even more efficient, replace the ASI with a Mach Meter. Then you can get 30 something to one l/d with an indicated airspeed of ZERO. OBTW, Its impossible to fly with an airspeed of zero, lift requires air movement over the wing on any conventional fixed wing airplane. You by definition still have airspeed if you are flying. Scott Scott did you miss the part in my posting where I said this airspeed was calibrated by itself and then while in the glider at differing airspeeds from 40 mph to 80 mph. using a GPS method posted on our website. It is also helicopter airspeed. Now I do think that at about 20 mph the airpspeed goes to zero... but again I did not test it in the aircraft for this slow a flight. What did confuse me was the low sink rate... but I could have been in rising air... and next time I will check my GPS groundspeed. But I have this on video and will post it for all to see. I was actually quite surprised myself and do not really know what to think of it. By the way this aircraft has a 3.6 lbs per sq ft wing loading and I easily fly at 90 to 100 mph. and I have videos of that too. Again that part of the spectrum has not been calibrated but it is interesting to see how well it flies at that speed. I will push for 130 mph in the sping when I have redone the canopy and fuselage. -mat |
#2
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So its under elevatored then.
Al "Marske Flying Wings" wrote in message ... No this is where you are quite wrong! There is pleanty of up elevator on the trailing edge of the main wing.... the air going over the top is separating due to the high angle of attack and this makes the elevator ineffective, so the nose lowers slightly and the glider picks up airspeed and it resumes normal flight. "spektr" wrote in message ... Bravo. So you are flying a glider with insufficient up elevator to cause a stall equipped with an airspeed indicator that doesn't register well on the low end of the spectrum. All wings stall when their critical angle of attack is exceeded. In its most benign form a stall will be recognnized as a slight vertical oscillation without a discernable break. If you had more elevator authority, it would get into this flight mode. Its inability to do so indicates a lack of elevator authority at slow speed. Your airspeed indicator reading zero means you are flying at a speed less than the minimum required to move the needle. You are probablu using a run of the mill ASI for airplanes. Nothing wrong with that, it just means you are slower than the gauge can indicate. You might consider an ASI for helicopters, they are much more sensitive at the lower end of the spectrum and will probably give you a better indication of whats going on. If you want to make your glider even more efficient, replace the ASI with a Mach Meter. Then you can get 30 something to one l/d with an indicated airspeed of ZERO. OBTW, Its impossible to fly with an airspeed of zero, lift requires air movement over the wing on any conventional fixed wing airplane. You by definition still have airspeed if you are flying. Scott Scott did you miss the part in my posting where I said this airspeed was calibrated by itself and then while in the glider at differing airspeeds from 40 mph to 80 mph. using a GPS method posted on our website. It is also helicopter airspeed. Now I do think that at about 20 mph the airpspeed goes to zero... but again I did not test it in the aircraft for this slow a flight. What did confuse me was the low sink rate... but I could have been in rising air... and next time I will check my GPS groundspeed. But I have this on video and will post it for all to see. I was actually quite surprised myself and do not really know what to think of it. By the way this aircraft has a 3.6 lbs per sq ft wing loading and I easily fly at 90 to 100 mph. and I have videos of that too. Again that part of the spectrum has not been calibrated but it is interesting to see how well it flies at that speed. I will push for 130 mph in the sping when I have redone the canopy and fuselage. -mat |
#3
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On Thu, 31 Jul 2003 17:27:46 UTC, "Marske Flying Wings"
wrote: : No this is where you are quite wrong! There is pleanty of up elevator on the : trailing edge of the main wing.... the air going over the top is separating : due to the high angle of attack and this makes the elevator ineffective, so : the nose lowers slightly and the glider picks up airspeed and it resumes : normal flight. Which is, effectively, exactly what he said... : "spektr" wrote in message : ... : So you are flying a glider with insufficient up elevator to cause a stall Ian |
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