17.6 meter tips for Ventus C ?

I'm sure the 17.6 tips help the Ventus B a lot, but high speed could present a problem.................remember the guy that added unauthorized tip extensions that worked great until he started a high speed final glide. As some point, the wing twisting (leading edge down) started increasing the speed until full back elevator wasn't enough to stop it!............ Pilot is no longer with us!
If I was flying a 17.6 Ventus B, I'd back off 20 knots (or more) on the VNE and Rough air redline.
Hope this helps,
JJ

On Saturday, October 27, 2018 at 5:52:24 PM UTC-6, wrote:
I'm sure the 17.6 tips help the Ventus B a lot, but high speed could present a problem.................remember the guy that added unauthorized tip extensions that worked great until he started a high speed final glide. As some point, the wing twisting (leading edge down) started increasing the speed until full back elevator wasn't enough to stop it!............ Pilot is no longer with us!
If I was flying a 17.6 Ventus B, I'd back off 20 knots (or more) on the VNE and Rough air redline.
Hope this helps,
JJ

The 17.6 m addition on Ventus B #61 was NOT UNauthorized, but was authorized by the designer. He obviously knew what he was talking about. Neither I nor the owner before me ever had any problems at high speeds in 2450 hours of airtime, mostly in the strong thermal west. We're still here. But there's certainly nothing wrong with being careful and flying slower in any glider. I did my share of that, too.

I hear you, we got a reluctant OK to add 2 meters to the ASH-25 a few years back. Worked fine till I pushed hard finishing at Ephrata. We crossed the finish line doing red-line at 50 feet. Got the good finish and pulled up and rolled left because the finish was in the middle of the field and we needed to get back ease in order to land westbound on the ramp. At 45 degrees left bank, I applied right aileron, but the ship kept rolling left! Full right stopped the left turn and things quickly returned to normal because the nose was up and airspeed was decaying rapidly. I was shook but didn't realize how bad the situation could have been until I talked to the guy who was on the finish gate. He was looking right down my left wing and said the wing was bowed up in the center section but bowed down at the tip.........looked like a sign wave! He said it was the scariest thing he had ever seen! Apparently, my left aileron input caused the wing tip to dig-in and left me doing an uncommanded hard left turn at 50 feet!
No more wing extensions for this Glider-guider!
JJ

On Sunday, October 28, 2018 at 8:49:10 AM UTC-5, wrote:
At 45 degrees left bank, I applied right aileron, but the ship kept rolling left!

JJ, that sounds like classic aerolastic twisting of the wing - shades of B-47s!

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