relative climb performance

Q. All the gliders below join the same thermal at
2000 feet. In which order will they reach 5000 feet.
Discuss.

LS7
Discus
ASW19
DG300
Libelle
ASW20
LS6

John

[Lars Peder Hansen]

Depends a lot on the nature of the thermal. Weak, crummy, narrow and
turbolent ones favor some gliders while strong, wide & steady ones favor
other types. -And then, of course, it depends on the wing loading, some
types are good climbers at other wing loading ranges than others.

- Actually, the above is just useless theory. In the real World, the Libelle
always climbs better than anything you can throw at it ;-)

/Lars Peder


> wrote in message
...
> Q. All the gliders below join the same thermal at
> 2000 feet. In which order will they reach 5000 feet.
> Discuss.
>
> LS7
> Discus
> ASW19
> DG300
> Libelle
> ASW20
> LS6
>
> John
>
>
>

[Eric Greenwell]

wrote:
> Q. All the gliders below join the same thermal at
> 2000 feet. In which order will they reach 5000 feet.
> Discuss.
>
> LS7
> Discus
> ASW19
> DG300
> Libelle
> ASW20
> LS6

Were these chosen at random, or did you have a larger goal in mind
besides a discussion to while away the day? The thermal size will affect
the answer, in any case, as the difference in wing loadings will result
in significant differences in circling radii.

Even so, I can report that in contest conditions, the LS6, in the hands
of better pilots than myself, did outclimb my ASW 20 C.


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

[Andy]

To have any meaningful discussion you'll need to specify the wing
loading, the thermal strength, and the characteristics of the thermal
(big, smooth, small, turbulent etc.).

Without that input I'd assume that the glider with the lowest wing
loading and slowest stall speed will win. Is that the Libelle?

On the other hand I often outclimbed lighter loaded Libelles with my
ASW 19. In tight and/or broken thermals pilot technique can override
the differences in gliders.

Andy

OK, assume standard British 2 knot thermals. Gliders
have no water in. Thermals are small but smooth.

Reason for the question....I can get L:D info off the
net, but not climb data...

John


At 18:36 14 September 2005, Andy wrote:
>To have any meaningful discussion you'll need to specify
>the wing
>loading, the thermal strength, and the characteristics
>of the thermal
>(big, smooth, small, turbulent etc.).
>
>Without that input I'd assume that the glider with
>the lowest wing
>loading and slowest stall speed will win. Is that
>the Libelle?
>
>On the other hand I often outclimbed lighter loaded
>Libelles with my
>ASW 19. In tight and/or broken thermals pilot technique
>can override
>the differences in gliders.
>
>Andy
>
>

[Bob Kuykendall]

> Q. All the gliders below join the same thermal at
> 2000 feet. In which order will they reach 5000 feet.

The one being flown by the pilot who considers it "their thermal."

[Andy]

Minimum sink speed and minimum sink rate should provide some clues.
That data should be available. The stronger the thermal the more pilot
technique overrides small difference in glider sink. In large weak
thermals almost nothing will prevent the lower sink rate glider
climbing better and topping out higher. That effect is obvous, and
frustrating to the low pilot, at contest pre-start gaggles when the max
start height is greater than top of lift.

Andy

[[email protected]]

to have a REALLY meaningful discussion you should have added a pilot
name next to each ship.
BJS

[[email protected]]

Thanks Eric !
But I've switched brands...