Discus 2a vs Arcus @ 200km/h - EGC 2013

On 24/07/2013 23:10, wrote:

This video presents final glide of his Discus 2a wing to wing with

Arcus flying at 200km/h. As you can see at this speed performance

of 20m span glider is no better than 15m Discus 2a.


course not. the drag penalty for the extra span kills you at high
speeds. when they slow down the arcus will walk away.

When they slow down a Libelle would walk away from both of them. But
that's evading the issue. 200ks (108 kts) is hardly high speed in a
modern glider. When DOES the Arcus earn its keep?

GC

On Wednesday, July 24, 2013 7:40:07 AM UTC-7, GC wrote:
On 24/07/2013 23:10, brayera wrote:



This video presents final glide of his Discus 2a wing to wing with



Arcus flying at 200km/h. As you can see at this speed performance



of 20m span glider is no better than 15m Discus 2a.





course not. the drag penalty for the extra span kills you at high

speeds. when they slow down the arcus will walk away.



When they slow down a Libelle would walk away from both of them. But

that's evading the issue. 200ks (108 kts) is hardly high speed in a

modern glider. When DOES the Arcus earn its keep?



GC

Increasing wing span is the solution to induced drag. At high speeds, Cl is low therefore Ci is low therefore wingspan is no longer the solution. We are not breaking new ground here, this is 100 year old information. However against the Libelle, my money is on the Arcus at any speed.

"When DOES the Arcus earn its keep? "

In a difficult early stage of my task this afternoon with weak climbs, I was embarassed that in my Arcus M (at 750kg) I was struggling to keep up with a less experienced if very promising pilot in a Cirrus. Later in the day, the Cirrus landed in a field and I completed my task satisfactorily.

The Arcus handles like a modern 18m glider, and performs more or less like one except in very strong or very weak conditions. It is also the best handling two seater (I hope I won't become jealous when the ASG32 and Twin Shark are available in the market). Nobody would suggest buying any of these gliders if you did not want a two seater.

Is it good value? Well, you could have just as much 2 seat fun in a K7. When asked about the cost of gliding, I always say that you can have as much fun in a glider you buy for $10k as in a $400k supership, and that people spend as much on their gliders as they want to. I enjoy the feeling that I have the best of its particular type and I guess that's why I spent the money..

Mark Burton, flying an Arcus M and an ASH 26E from London Gliding Club, UK.

On Friday, 19 July 2013 10:47:45 UTC+1, Wolf Aviator wrote:
Hi ladies and gents,



Here is a video made by Sebastian Kawa on ECG 2013 at Ostrów in

Poland.



This video presents final glide of his Discus 2a wing to wing with

Arcus flying at 200km/h. As you can see at this speed performance

of 20m span glider is no better than 15m Discus 2a.



http://www.youtube.com/watch?v=5xrDLQ61474



quote (1m 8s of video):

"A why they're buying such expensive gliders...".

Regards

Wolf

http://youtube.com/user/WolfTheAviator

"my Arcus M (at 750kg)"

I saw an Arcus being positioned on a grid. It took way to many people to move it. The second day when the owner looked for help every one looked the other way . The darn thing is just heavy.

It's a 2 seater. It should not need more than 2 to push it. And it does not need much pushing. Tow out, taxi to the front of the grid when ready to go. Having said that, it did not like the soft ground at my club's grass airfield during the winter.

On Friday, July 19, 2013 10:47:45 AM UTC+1, Wolf Aviator wrote:
Hi ladies and gents,



Here is a video made by Sebastian Kawa on ECG 2013 at Ostrów in

Poland.



This video presents final glide of his Discus 2a wing to wing with

Arcus flying at 200km/h. As you can see at this speed performance

of 20m span glider is no better than 15m Discus 2a.



http://www.youtube.com/watch?v=5xrDLQ61474



quote (1m 8s of video):

"A why they're buying such expensive gliders...".

Regards

Wolf

http://youtube.com/user/WolfTheAviator

The video - its contest day 7 at the EGC Ostrow, 17/7/2013, Sebastian Kawa and Belgian Arcus 2AS both finish at 16:21:11. Sebastian wins the Standard class day (and the comp) and during a relaxing final glide at 200kph in close formation with the Arcus he fills his time by hand filming the other glider. Cool!

John Galloway