I built it years ago. Sitting on the shelf in the hangar. But the shop needs to add/remove washers from the wing.
That's above 5, not 1.6.
Talking about POH numbers. For every 1000 ft you can glide 1.6 miles
That's more like 8. 1.6 miles is over 8000 feet.
ahh!!. alright. don't use foreflight. my panel mount Garmin shows the distance to the nearest airport in nm, so I stick to 1.6 nm glide per 1000 ft AGL
remember thats at max gross. you are not going to fly always at max gross. which begs another question... would it glide more if you are light?
Yes?
That's before POHs were standardized. A taper wing would be more sensible about things like that (just because of the date).
No. Speed is higher at max gross but glide ratio is approximately the same if you are at best glide.
so you are saying the best glide speed would change, but the glide distance would be same whether I am at 2500 or 1900? logically lighter things floats more, so... whats the physics behind this?
Are you floating?
Well technically may be. Won't the weight change lift? Not arguing, trying to understand.
Technically maybe? Is your aircraft lighter-than-air? If not then how can it be floating?
@WannFly this perplexed me for a long time after and I finally just accepted it as part of life, lol. I was particularly perplexed by why it is that sailplanes use water ballast. Seems counter-intuitive to add weight to something like a sailplane.. and it goes along to the same point that @Clark1961 was making about glide ratio being the same regardless of weight
i understand the curve doesnt change with weight.. trying to wrap my head around why. what you and @Tantalum mentioned makes sense. still trying to wrap my head around the "why". i guess gravity is stuck in my mind and i have a mental picture of a feature and an apple (damn newton) falling from same height and one takes longer to hit the ground, and i may have always correlated that to weight. my school physics teacher is somewhere ashamed of me rt now
I eventually just forced myself to accept it. But one thing that helped me visualize, was imagining an inclined plane (geez, we really are back to high school physics
) and two balls on it. One ping pong ball and one bowling ball. Both will roll down the plane and hit the ground at the same exact point, but the bowling ball will get there much faster
I eventually just forced myself to accept it. But one thing that helped me visualize, was imagining an inclined plane (geez, we really are back to high school physics
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Ignore the parasitic component of the drag curve for a minute. The remaining drag is all induced. What causes the induced drag? Lift and lift is constant for unaccelerated flight and a fixed weight, right? In fact lift has to equal weight (ignoring tailplane forces). Now consider a heavier weight wth the same wing. The wing will have to generate more lift. More drag will be induced but the General shape of the induced drag curve will not change. Of course the stall speed is higher so the endpoint shifts a bit.
Newton just screamed.I eventually just forced myself to accept it. But one thing that helped me visualize, was imagining an inclined plane (geez, we really are back to high school physics
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We're not in a vacuum. Otherwise they would get there at the same time AND same point. But if we were in a vacuum the whole discussion of "best glide" would be moot!
Newton was a lousy engineer but a great theoretician. In this case the balls have parasitic drag but little/no induced drag. The result is that the heavier ball will accelerate faster against parasitic drag than the lighter ball. With the airplane there is no acceleration so while the simplified ball model has a similar outcome to illustrate the speed of the heavier aircraft it does not in anyway represent the physics.
You bet he did. 'Cause someone doesn't understand the difference between falling/sliding and rolling. It make a HUGE difference. Different objects fall at the same rate, but do NOT roll at the same rate.
Totally agree. But the whole thought experiment at least helped me just accept it as part of life. The glider thing I posted above was what a glider pilot maybe a decade ago explained to me (when I first started pondering this) and his analogy made me think of the ball thing
It was an abbreviated thought experiment that helped me visualize it. Not something I handed down as decree
"Thought experiment" now I'm going to shoot you. Hold still.
Don't forget the bird flying around inside your plane
