Ventus C, 15m vs 17.6m

[Mike N.]

Just curious, how is the performance of the Ventus C with 17.6m tips installed versus standard 15m with good winglets?

I have done some searching and seen some consensus that the 16.6m tips are typically not used much due to the performance degradation at high air speeds. But what about the 17.6 tips?

Expected conditions would be soaring in Florida.
I also fly Utah, but not thinking I'd need the extra L/D in Utah unless on a weak day.

Also are the 17.6 tips available? What would a set of 17.6 tips cost?

Thanks,
Mike

[Tim Taylor]

The 17.6 are similar to the 16.6 tips. None were created before improvements in winglet design so they tend to provide improvements at lower speeds but drop off at the higher end. I can’t remember if the 17.6 C had the same 980 pound limitations as the 16.6 on the B models. This limits the usefulness on stronger days.

The tips are better if they have winglets, but most of these were modified after manufacturer. I would prefer to fly a C in 15m with Maughmer winglets than 17.6 without winglets. The winglets help the Ventus groove and improved the stall characteristics.

Unless the glider has the tips when you buy it is very difficult to find a set later.

The longer tips are nice in lift less than 3 knots, for longer glides at slow speed, and floating around on weak days. Without winglets the glider does have a shorter fuselage and rudder optimized for 15m so yaw can be a factor.

[Bob Gibbons]

On availability; at one time S-H offered a retrofit kit that allowed
an owner to convert the 16.6m tips to 17.6m tips. This kit was
provided with 17.6m sleeves that were bonded to the 16.6m tips (after
cutting off about 4 inches of the 16.6m tip). The kit included all
required materials, including the epoxy. Not a complex job, but it did
required careful jigging to assure proper alignment.

Details are available in TN 346-11, still available on the S-H
website. Reference is made to drawing HS8-50.307 describing how the
tip extensions are attached.

I purchased and installed this kit on my Ventus cT in the early
2000's. I doubt the kit is still available, but it would not hurt to
inquire.

I typically fly with the 17.6m tips, except in very strong conditions
with water ballast when I drop back to 15m with winglets. I just like
the way the ship looks and handles at 17.6m.

Bob

[Mike N.]

Thanks for the information.

How is the L/D and sink rate versus the 15 m with winglets?

Again looking at Florida as a primary operations area. So light to moderate lift and not high as compared to Utah or other mountain regions.

[dan.cross...@gmail.com]

Longer wings are better for weaker conditions. As mentioned before, the 17.6 meter wing make the glider "fish tail" a bit in a straight line flight.
Dan

[Tango Whisky]

I've been flying my Ventus cM in 17.6 m configuration for about 1500 hours, and there is no fishtailing, and you can let the stick go on a thermal. Overall behaviour is very begnin.

Measured performance is 47:1. For European conditions, its max loading of 43 kg/m2 is perfect. I would never consider flying it in 15 m.

[Bob Gibbons]

I have not noticed this flight characteristic in 20 years flying a
Ventus cT.

Bob

[Frank Whiteley]

On Saturday, July 27, 2019 at 8:40:41 PM UTC-6, dan.cross...@gmail.com wrote:
> Longer wings are better for weaker conditions. As mentioned before, the 17.6 meter wing make the glider "fish tail" a bit in a straight line flight.
> Dan

I get this in my Kestrel 19, but always considered it to be resulting from rudder flow and the lack of good sealing so the flow attaches and detaches side to side, e.g. laminar to turbulent, thus the movement.

However, you seem to describe something that happens on your Ventus that doesn't happen with in the 15m configuration, is that correct?

Frank Whiteley

[crosscou...@gmail.com]

I will explain what happens. When flying in the 17.6 configuration, and letting go of the rudder pedals on a straight line, every time a gust pushes the nose to one direction the nose will stay there and you are not flying coordinated any more. Need rudder input to correct. No rudder input and the nose will move from side to side randomly (fish tail). No big deal, but needs attention.
This does not happen in 15 M configuration.
I believe in later Ventuses they increased the tail.
Dan

[Mike N.]

I saw this fishtailing was an issue in the Ventus A&B was it resolved in the C or not?

Thanks

[Tango Whisky]

Again : My Ventus cM doesn't do that.
Maybe I have a special one ?

[cliff...@gmail.com]

I had a Ventus B 16.6 and it never did that. It had the C mod on the root fairing.

CH

[Mike N.]

Good to know. Thanks.

[Glidergeek]

Fishtailing? You mean yaw?

[Gary Wayland]

Hi Mike,

Where will you be flying in Florida?

Flying against Alfonso Eurado (E9) and Benny Flowers in their Ventus C sailplanes, you don't need 17-meter tips. It was an awesome machine at 15M! Benny was always playing with new winglets but Fonzie still had an advantage, (IMHO) with the stock wings.


Best Regards


Gary
ASW27b
(SQ)
Currently at Seminole Lake

[crosscou...@gmail.com]

Yes neutral stability in yaw. Requires some rudder input to keep going straight on a bumpy day.
Dan
On Friday, August 2, 2019 at 8:56:48 PM UTC-4, Glidergeek wrote:
> Fishtailing? You mean yaw?

[Charlie M. (UH & 002 owner/pilot)]

Fonzie was Fonzie....sorta hard to compare.
Yes, I flew against him a number of times in the NE.
Yes, I have heard of some amazing (even for me) outlandings.

I miss him, quite a character, but, always willing to help.....him and his better 1/2 and dog.....

[Gary Wayland]

I had more fun flying with Fonzie at the club in Miami.

A short story.... There are many with the Fonz.

Late one Sunday afternoon, we were all sitting around the table after a good day of soaring, all telling lies on how bad we beat our buddies in the last thermal.

Oh wait, where's Fonzie?

Hey, get on the radio and see if he's out there... Late in the day, sun dropping under the horizon.

Hey Fonz, are you out there, we barked over the radio?

Fonzie comes back, yeah, I'm fifty miles out coming back from flamingo and not sure if I'm going to make it. Flamingo is a complete track over the Florida everglades with coral rocks and alligators...

OK, Fonz, as we asked again, can you get home?

The typical Fonz answer, "GOT TO" (It was so perfect with that Ecuadorian accent)

A short time later, as always, 3 high-speed passes and a beautiful landing in his Ventus C...

I miss Alfonso...

RIP, E9.

Gary

[Mike N.]

We are in the process of moving to the North Port area from Utah.

I'll be flying out of TBSS or Seminole. I flew at TBSS for a month and enjoyed it.
I have yet to fly at Seminole and am looking forward to it.

[Gary Wayland]

Mike,

Is TBSS in Zephyrhills?

I just relocated from Treasure Coast Soaring in Vero Beach to Seminole. My brother and a bunch of great guys over there but work forced a move because of travel times.

I've flown at Seminole many times. Great place to soar...


What is your tail Competition Letters?

Gary
'SQ'

[Mike N.]

Yep Tampa Bay Soaring Society in Zephyrhills.
A good club for sure. However only open on the weekends and Wednesdays.
So I am retiring and will be able to fly during the week which is why I might base out of Seminole.

I just got my competition number so I have no history on the number. It's 1M

I'm going to start doing OLC once I get settled in.

Mike