A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Soaring
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

LS3A performance



 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #3  
Old June 19th 07, 02:57 PM posted to rec.aviation.soaring
Chip Bearden
external usenet poster
 
Posts: 69
Default LS3A performance

I owned an LS-3 for 13 years. In my experience, all LS-3 versions
climbed equally well but many (not all) A models didn't run as well.
The lower weight of the 3A should have had some impact on climb but I
never saw it. The most likely cause of the cruise discrepancy is wing
profile, for two potential reasons. First, as you note, is that the A
model airfoils may have been thicker than they should have been (per
Dick Johnson and some correspondence in Soaring mag. from the factory
that followed Dick's test). Second, at least for the 3, is shrinkage
over the spar caps that caused a flat spot to develop after a few
years with significant impact on cruise performance. I contoured my
wings twice and profiled them over the spar caps once (to build up
this flat spot) and my glider was equal to the ASW 20s, Ventus, and
LS-6. A few other pilots who did similar things had the same
experience (e.g., Jim Cox in TX, IIRC). Unmodified LS-3As fell away
pretty fast at higher speeds, but so did unmodified 3s.

The above covers why a 3 might perform better than a 3A. Another
factor that relates only to how a 3 or 3A might perform against other
types is that the leading edge of the wing was said to be too blunt,
especially on the outer wing. The aforementioned Jim Cox profiled his
entire wing and built up the leading edge to the correct profile and
saw a dramatic improvement. But as far as I know, both models of LS-3
had this characteristic.

Personally, I'd probably take an LS-3 over an LS-3A even though the
wing is heavier--the 3 has fully automatic controls whereas the 3A
requires some control connections--but I suspect that either glider
would perform very well with the proper wing profile. They're still
very nice, very strong gliders. It's not well known that when the LS-3
and ASW 20 first appeared here in the US around 1977, the '3 was the
hot ship to have.

Chip Bearden
ASW 24 "JB"
New Jersey, USA

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
LS3a or Mini Nimbus [email protected] Soaring 14 November 11th 06 10:36 PM
Complex / High Performance / Low Performance R.T. Owning 22 July 6th 04 08:04 AM
FS - LS3a Simon Waddell Soaring 0 January 17th 04 04:05 PM
OPINIONS ON AN LS3A Gordon Schubert Soaring 6 November 14th 03 10:41 AM
Drag of LS3 compared LS3a. Peter Warburton Soaring 0 August 18th 03 06:59 AM


All times are GMT +1. The time now is 02:59 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 AviationBanter.
The comments are property of their posters.