"A" vs "B"

[C2]

How much performance advantage does an "A" model (Ventus or Discus) have over a "B" model. Looking for some numbers, but I can't seem to find anything definitive.

[Bob Gibbons[_2_]]

On Wed, 30 Sep 2015 12:45:17 -0700 (PDT), C2 >
wrote:

>How much performance advantage does an "A" model (Ventus or Discus) have over
>a "B" model. Looking for some numbers, but I can't seem to find anything definitive.

Dick Johnson tested and reported the results on his Ventus A in
December 1981 SOARING, and followed this up in June 1982 with his
report on a Ventus B.

Page 30 of the 2nd article shows an overlay of the A vs B polar plots.
Only over 100 kts can you see a small seperation develop between the
two plots.

Perhaps a more important factor is the small cockpit of the A model,
and the lack of the self-connecting controls of the B model.

Check the SSA website for the full reports.

Bob

[Richard[_9_]]

On Wednesday, September 30, 2015 at 1:38:28 PM UTC-7, Bob Gibbons wrote:
> On Wed, 30 Sep 2015 12:45:17 -0700 (PDT), C2 >
> wrote:
>
> >How much performance advantage does an "A" model (Ventus or Discus) have over
> >a "B" model. Looking for some numbers, but I can't seem to find anything definitive.
>
> Dick Johnson tested and reported the results on his Ventus A in
> December 1981 SOARING, and followed this up in June 1982 with his
> report on a Ventus B.
>
> Page 30 of the 2nd article shows an overlay of the A vs B polar plots.
> Only over 100 kts can you see a small seperation develop between the
> two plots.
>
> Perhaps a more important factor is the small cockpit of the A model,
> and the lack of the self-connecting controls of the B model.
>
> Check the SSA website for the full reports.
>
> Bob

My Ventus b has self-connecting controls.

Richard

[[email protected]]

On Wednesday, September 30, 2015 at 3:38:28 PM UTC-5, Bob Gibbons wrote:
> On Wed, 30 Sep 2015 12:45:17 -0700 (PDT), C2 >
> wrote:
>
> >How much performance advantage does an "A" model (Ventus or Discus) have over
> >a "B" model. Looking for some numbers, but I can't seem to find anything definitive.
>
>
> Perhaps a more important factor is the small cockpit of the A model,
> and the lack of the self-connecting controls of the B model.

Only the Ventus has the different control connections between A&B, IIRC. The Ventus A is only auto-connect elevator. Ventus B and all Discii are full auto-connect.

FWIW, the FAI handicaps the two the same. The SSA appears to give a lower handicap (lower == higher performance in SSA-land) to the B, but that is likely due to the higher empty weight of the B vs the A.

[Tim Taylor]

General rule of thumb is about 0.5 percent. The true advantage comes in wider wing loading range from the lower empty weight. Great gliders if you fit but more difficult to sell to the "average" American pilot.