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

air extractor for asw19 and asw20



 
 
Thread Tools Display Modes
  #1  
Old October 17th 17, 02:47 AM posted to rec.aviation.soaring
[email protected]
external usenet poster
 
Posts: 69
Default air extractor for asw19 and asw20

I just installed a very cool - pun intended - air extractor in my ASW19. Its a nifty device that replaces that little hatch cover where the control connections are. My guess is that it was made on a 3D printer. Anyway, I couldn’t believe how well it worked and so I’m putting a shameless plug for that thing here. I got it from an outfit in the UK called LJ Panels. I don’t often get carried away raving things, but this one is the cats meow.

Ads
  #2  
Old October 17th 17, 04:03 AM posted to rec.aviation.soaring
JS[_5_]
external usenet poster
 
Posts: 79
Default air extractor for asw19 and asw20

On Monday, October 16, 2017 at 6:47:55 PM UTC-7, wrote:
I just installed a very cool - pun intended - air extractor in my ASW19. Its a nifty device that replaces that little hatch cover where the control connections are. My guess is that it was made on a 3D printer. Anyway, I couldn’t believe how well it worked and so I’m putting a shameless plug for that thing here. I got it from an outfit in the UK called LJ Panels. I don’t often get carried away raving things, but this one is the cats meow.


Is it anything like the ones that Paul Hanson sold years ago?
Jim
  #3  
Old October 17th 17, 04:06 AM posted to rec.aviation.soaring
Paul Agnew
external usenet poster
 
Posts: 124
Default air extractor for asw19 and asw20

I just bought the same extractor for my ASW-19 and am waiting to install it. Mine will require a small modification to the block of wood under the opening so the front edge lip will slide in.

Did you cut the vent holes in the aft bulkhead?

Paul A.
  #4  
Old October 17th 17, 05:46 AM posted to rec.aviation.soaring
Paul Agnew
external usenet poster
 
Posts: 124
Default air extractor for asw19 and asw20

http://ljpanels.co.uk/test/index.php...traction-ducts

FYI
  #5  
Old October 17th 17, 04:05 PM posted to rec.aviation.soaring
Dan Marotta
external usenet poster
 
Posts: 2,813
Default air extractor for asw19 and asw20

Pretty nifty looking bit of kit!* But I'd think you'd have to make a
cover to close off the ring bulkhead aft of the vent.

On 10/16/2017 10:46 PM, Paul Agnew wrote:
http://ljpanels.co.uk/test/index.php...traction-ducts

FYI


--
Dan, 5J
  #6  
Old October 17th 17, 05:08 PM posted to rec.aviation.soaring
Ramy[_2_]
external usenet poster
 
Posts: 312
Default air extractor for asw19 and asw20

Curious what you mean by "how well it works". The theoretical small performance improvement will be very difficult to measure if possible at all. Or do you refer to the reduced cockpit noise?

Ramy
  #7  
Old October 17th 17, 06:12 PM posted to rec.aviation.soaring
Paul Agnew
external usenet poster
 
Posts: 124
Default air extractor for asw19 and asw20

The purpose of the extraction vent is to increase the available airflow to the cockpit. The ASW-19 has NACA vents under the wing roots to draw air in, but there is no clear path for it to exit. The extraction vent, and modification of the bulkhead to allow airflow, gives the air someplace to go and reportedly greatly increases the comfort level in the cockpit. Noise reduction is primarily due to being able to keep the canopy vent closed and a reduction of "pressurized" air leaking under the canopy seals.

Any performance benefits are a bonus in my book and not a serious consideration unless you are a hard-core performance tweaker looking for every .1% gain.

Paul A.
  #8  
Old October 17th 17, 09:25 PM posted to rec.aviation.soaring
Charlie M. (UH & 002 owner/pilot)
external usenet poster
 
Posts: 615
Default air extractor for asw19 and asw20

There have been mods over the years to increase airflow INTO the cockpit, but part of the issue is getting it back out efficiently without a performance hit.
Pressurized air will find a way out, sometimes through the wing by the control hingeline, also not good.
So some air is forced down the tail boom to the base of the rudder, turbulent flow and blanking part of the rudder.
The "turtledeck" is lower pressure and adding air can smooth fuselage airflow.
Also, the lower pressure can help draw out cockpit air, making the vents work better.

Flying high may not need this as much due to lower ambient air temp, flying lower, ambient can be much higher and sitting under a greenhouse.

I can attest to flying with some flavor turtledeck vent as greatly aiding cockpit airflow and possibly helping fill in fuselage turbulent airflow.
You may also have to do some mods to allow air from the cockpit to under the turtledeck (holes in the package shelf for example) to aid this mod.
  #9  
Old October 17th 17, 09:57 PM posted to rec.aviation.soaring
Paul Agnew
external usenet poster
 
Posts: 124
Default air extractor for asw19 and asw20

Alan from LJPanels sends a template for adding three holes to the shelf/bulkhead and includes three round vents to install in order to prevent anything from falling through the holes onto the control linkages.

Paul A.
  #10  
Old October 18th 17, 12:24 AM posted to rec.aviation.soaring
[email protected]
external usenet poster
 
Posts: 69
Default air extractor for asw19 and asw20

Some of the ASW19s (and maybe the 20’s) have a fold down wood bulkhead. There is a 1/2 gap around the perimeter that lets the air escape into the fuselage where the air extractor is located. For gliders with a fiberglass bulkhead, the kit includes a template to cut some holes, and also some round plastic screens that prevent the anything other than air from getting through.

As far as glider performance goes, the difference is probably insignificant.. But when it comes to pilot comfort, the airflow through the cockpit was probably double what I had before, maybe more.
 




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
ASW19 for sale [email protected] Soaring 2 September 12th 16 10:07 PM
ASW19 Inner Tube [email protected] Soaring 1 September 21st 15 03:54 PM
Air extractor for sustainer and motor gliders? [email protected] Soaring 12 August 26th 15 07:41 AM
Air Extractor: Better than a Plastic Jesus? [email protected] Soaring 23 December 18th 13 09:48 AM
asw19 airbrake kit steve[_2_] Soaring 2 April 7th 11 08:32 PM


All times are GMT +1. The time now is 06:39 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright 2004-2017 AviationBanter.
The comments are property of their posters.