It is currently Thu Oct 18, 2018 1:45 am

All times are UTC - 6 hours




Post new topic Reply to topic  [ 7 posts ] 
Author Message
 Post subject: Glider low passes
PostPosted: Mon Dec 10, 2012 5:32 pm 
Offline
User avatar

Joined: Mon Jul 25, 2011 11:58 am
Posts: 4912
Location: Austin, TX
Not RC gliders, but real ones. Check out the energy retention! :)

_________________
Chris Boultinghouse


Top
 Profile  
 
 Post subject: Re: Glider low passes
PostPosted: Mon Dec 10, 2012 7:48 pm 
Offline
User avatar

Joined: Sat Dec 10, 2011 2:47 pm
Posts: 1385
Very cool sounds.
So they get altitude, dive and then dump the water ballast to be able to climb back up?

_________________
Bunch of helis and a bunch of planes controlled by a radio


Top
 Profile  
 
 Post subject: Re: Glider low passes
PostPosted: Mon Dec 10, 2012 8:42 pm 
Offline
User avatar

Joined: Mon Jul 25, 2011 11:58 am
Posts: 4912
Location: Austin, TX
karl k wrote:
Very cool sounds.
So they get altitude, dive and then dump the water ballast to be able to climb back up?
No, they load up with water ballast so they can go faster on long x-country races or for strong lift conditions. They have to dump it prior to landing so they are at "landing weight", pretty much like an airliner can't immediately land after taking off with a full load of fuel for a long flight. From the Glider Wiki:

Quote:
Modern competition gliders carry jettisonable water ballast (in the wings and sometimes in the vertical stabilizer). The extra weight provided by the water ballast is advantageous if the lift is likely to be strong, and may also be used to adjust the glider's center of mass. Moving the center of mass toward the rear by carrying water in the vertical stabilizer reduces the required down-force from the horizontal stabilizer and the resultant drag from that down-force. Although heavier gliders have a slight disadvantage when climbing in rising air, they achieve a higher speed at any given glide angle. This is an advantage in strong conditions when the gliders spend only little time climbing in thermals. The pilot can jettison the water ballast before it becomes a disadvantage in weaker thermal conditions. Another use of water ballast is to dampen air turbulence such as might be encountered during ridge soaring. To avoid undue stress on the airframe, gliders must jettison any water ballast before landing.

_________________
Chris Boultinghouse


Top
 Profile  
 
 Post subject: Re: Glider low passes
PostPosted: Tue Dec 11, 2012 1:40 am 
Offline
User avatar

Joined: Sun Jul 31, 2011 3:43 pm
Posts: 2513
Location: Houston, Texas
Wow that was awesome!

those are some crazy pilots!

_________________
Home of Burntwood RC


Top
 Profile  
 
 Post subject: Glider low passes
PostPosted: Tue Dec 11, 2012 8:23 am 
Offline
User avatar

Joined: Sat Dec 10, 2011 2:47 pm
Posts: 1385
Neat info. Thanks Chris. :thumbsup


Sent from my iPhone with my mind.

_________________
Bunch of helis and a bunch of planes controlled by a radio


Top
 Profile  
 
 Post subject: Glider low passes
PostPosted: Thu Dec 13, 2012 2:08 pm 
Offline

Joined: Mon Jul 25, 2011 5:07 pm
Posts: 778
Location: West sussex, UK
Nice.

I see they are still using the vertical string method for a turn and slip meter.
I am surprised you don't see that in fpv setups, maybe as things get more realistic people will start using it, seems like a cheap and simple way of seeing if you have co-ordinated turns in your fpv bird. If it works for full scale then it must be good...

Thanks for posting I will have to send tat to my dad he will love it.

Cheers
Steve


Top
 Profile  
 
 Post subject: Re: Glider low passes
PostPosted: Thu Dec 13, 2012 4:19 pm 
Offline
User avatar

Joined: Mon Jul 25, 2011 11:58 am
Posts: 4912
Location: Austin, TX
Yep, it's pretty hard to beat a piece of yarn taped to the windshield to determine whether you are coordinating your turns! :)

_________________
Chris Boultinghouse


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 7 posts ] 

All times are UTC - 6 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group