Real Word performance on the "B" model

[Green Bean]

Nice landing and beautiful weather. Looking at the Go Pro results shows that the landing was closer to 180 feet. The aircraft tail wheel touch down just before the Runway Threshold and before the beginning of the Threshold Markings and came to a stop beyond those markings. At Half Moon Bay Airport with a 5000 foot runway and 150 wide, the Threshold Markings are painted 150 long and 130 feet in width. So if you add the addition length of the 170 at 24 feet and 11.5 inches, your distance to stop would be pretty close to the 180 feet that was mentioned by Robw56.

[W.J.Langholz]

Nice Flying!!!!!! Thanks

W.

[W.J.Langholz]

Oh .....I forgot......Nice Plane too!!!!!!!


W.

[Bruce Fenstermacher]

Here's a video for you. Dead calm wind today at 5pm here at KHAF on runway 30. Fuel topped off and then hit the pattern with the GoPro on the left wing. ..... Or maybe it's the VG's!!

Or maybe it's the pilot who knows how to and is comfortable flying closer to the edge with those VG's. What would be interesting is another GoPro on the airspeed even though it wouldn't likely be accurate that slow, but still interesting.

[spduffee]

WOW! That was a short landing roll, Aryana. As soon as my baby is airworthy I am going to have to make a trip to Half Moon Bay and get some pointers.

[W.J.Langholz]

Aryana
Next time out could you do a dead stop take off roll, and maybe on over a 50' obstacle as well.....just for sh%$ and giggles eh

Thanks

W.

[W.J.Langholz]

www.youtube.com/watch?v=CG2cux_6Rcw




W.

[robw56]

Nice work, looks like about 200ft using the measuring tool on Google Earth.

[W.J.Langholz]

Aryana

I got to throw the BS flag on the belly cam one.......noway can that be real, it has to be photo-shopped.......that belly is WAY TO CLEAN!!!!!



Nice flying! thanks for sharing.

W.

[bagarre]

I mounted a GoPro on the belly once to get some landings.
The takeoff came out great but by the time I came around to land, the lens was oiled over.

[hilltop170]

My last glance at 50 ft was 55 mph, after that I have to keep my eyes outside the cabin!

This was power back to idle on downwind abeam the numbers. If I drag it in with power it can get even slower/shorter. I don't typically do that though. I like to practice spot landing with zero power in case I ever have to put it down off-field in an engine out situation.

Did you take any performance data before and after installing the VGs to see how much difference they actually make?

[hilltop170]

That's the same kind of performance increase I saw when I installed VGs on my Super Cub years ago. Without VGs it stalled at 42mph indicated, with VGs it stalled at 20mph indicated and would make rock solid approaches at 40mph indicated. And stalls were non-events, just add power and fly out without lowering the nose or losing altitude, very amazing improvement.

It looks like your pitch angle is not that much greater than normal on those stall landings but the tailwheel does hit first which is good for minimum ground roll.

[Bruce Fenstermacher]

It looks like your pitch angle is not that much greater than normal on those stall landings but the tailwheel does hit first which is good for minimum ground roll.

As Aryana wrote and I've said many times VGs make the airplane feel like it is flying faster so pilots naturally tend to fly slower than they otherwise would. Sure VGs reduced the stall speed but who knows to what because at that angle the airspeed indicator isn't working right anyway.

Many times I could have hooked the number 1 wire with my tail wheel hitting first. And many times it dropped the mains to the ground much harder than I liked.

[blueldr]

Afriend of mine, a retired Lockheed engineer, and some of his group ran VG tests on three cessna models using a C-170, c-180, and a C-182, down in Goodyear, AZ. The conclusion was that the VGs did very little for the Cessna wings in comparison to their effect on a Piper wing on a Super Cub. The VGs installed on the tail did provide a noticable improvement on on the low speed controllability of the elevator and rudder, particularly on the two tail wheel airplanes. I think this sounds quite reasonable in view of the almost exact similarity of the wings on the three test model airplanes. I also believe that all three test airplanes had the earlier Cessna wing configuration used prior the advent of the slightly "cuffed" wing on the later models.
Their conclusion,---- Not worth the cost.

[Bruce Fenstermacher]

So BL. Was your friend testing for actual reduction in stall speed or was he testing for control authority down to stall what ever stall speed happened to be.

There is a difference.

If the VGs give one rock solid control right to stall then one is more likely to fly closer to stall than they ever would without VG's

This is what I've said all along and what Aryana is saying.

It matters not that VGs on a Cessna wing may only lower the stall speed a mile an hour or two from what ever it was. What they do is allow one to control the wing with authority at stall speed. And that is something one would not do without VGs.

Here is a demonstration I use to do at altitude for people curious about the effect of VGs. I would, using any degree of flaps deployed, raise the nose of the airplane until a wing stalled. Which ever wing stalled and dropped I would raise with aileron alone to wings level. I would continue in the stall to raise which ever wing dropped using ailerons alone. I would also do 90 degree turns at will in this attitude. I could do it all day except eventually I'd ht the ground because my vertical speed would be in excess of 1500 ft a minute.

After the demonstration I'd let my passenger pilot take the controls and do the same. Makes believers in the value of VGs and their effect of control out of them. Most tell me they would never attempt it with their plane and one of those other planes had a leading edge cuff**. They understand it is not flying slower than they could, it is flying slower and more consistently with VGs than they would without that makes the difference.

** not saying VGs are better than a leading edge cuff.