Thread: DG-300 or LS-3?
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Old April 25th 10, 04:11 AM posted to rec.aviation.soaring
Eric Greenwell
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Default DG-300 or LS-3?

On 4/23/2010 6:10 PM, noel.wade wrote:
On Apr 23, 5:47 pm, Greg wrote:

That is a difference of only 30' of altitude each mile.


Greg -

Yes, it does seem like a paltry difference in altitude-per-mile.

But when you look at it in terms of competition flying, it equates to
a good 5 - 7 knots faster during inter-thermal cruising, for the same
sink-rate.

If you figure that 70% of a task is spent in cruise, that's a nice
advantage! Flying 85 knots versus 80 knots yields a 6% speed
difference in cruise. If you assume a similar climb rate (I know,
they may not be similar) and you assume that you spend 70% of your
flight in cruise, then the total performance advantage is 4%. But the
handicap difference between the DG-300 (0.95) and the LS-3 (0.937) is
only 1.4%

I know that the pilot matters more than the ship. I come from the
world of auto-racing and have experience in competition where bad
people think that fancy equipment will solve all of their
deficiencies. That's not the issue here... The issue for me is
whether its worth it to get the good ship *now* and have it for
several years, versus "practicing" with the DG-300 for a few years and
then moving over once I am "close" to winning...


What contest class do you want to fly it in? Sports class: I suspect the
handicaps are closer to correct than you would think from your
calculations. 15 M: the newer gliders like the ASW 27 are much better
than the LS3. Standard class: you can't fly the LS3 in Standard.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

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