 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
Doug Gray
Joined: 10 Jan 2006
Posts: 112
Location: Sydney, Australia
|
 Posted: Tue Oct 09, 2007 11:58 am Post subject: Altimeter error - ASI question |
 |
|
John,
Very interesting procedure for adjusting the Altimeter. I'm looking
forward to the outcome from Shirley.
Do you have a procedure for adjusting an airspeed indicator?
I have a very nice second hand ASI (Unknown German brand, model is
FM-440/4) but has an error at zero diff. pressure of ~25 kts. I have
not tested the range yet so I don't know if this is across the scale.
Can this be adjusted or do I have a dud?
TIA
Doug Gray
On Sun, 2007-10-07 at 12:54 -0500, John D. Heath wrote:
[quote]
Shirley,
Anything in an airplane that has preformed well for a long time and then
suddenly has a change should be looked at by someone with experience in that
field. That being said, and if you are sure that altimeter is otherwise
functioning correctly, with reasonable care try this. Adjust the altimeter
to airfield elevation. Near the adjustment knob there is a flat head screw.
Carefully turn it out until the head just clears the face of the instrument
but still is engaged in the threads. The screw is engaged in a small rod
that locks the knob in position. Try not to let it come out or lose it.
Slide the screw away from the adjustment knob to unlock it. With care, pull
out on the knob. In this position the knob will only adjust the Kollsman's
window. Set the QNH in the Kollsman's window. When manipulating the knob in
and out, use a very slight and gentle twisting force to accommodate its
movement. Move the knob to the in position, slide the screw/lock back to
where the screw can be turned in to its original position. If its within 50
ft you got it, if not, do it again.
Careful,
John D.
---
| | - The Matronics RV-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
| Back to top |
|
 |
altoq(at)cebridge.net
Guest
|
| Posted: Tue Oct 09, 2007 12:37 pm Post subject: Altimeter error - ASI question |
|
|
Doug,
That one has to go to the shop. I can say though, airspeed indicator errors
are generally in the Pitot/Static system. The main trouble spot seems to be
the Static Port position and height above the surrounding surface. There are
some very elegant solutions available for static ports, but in my opinion
they are just a fancy way to terminate the static tubing at skin level. A
cheap pop rivet with enough length to install the tubing on and a washer
placed between it and the head of the gun when it is installed has worked
for me many times. The washer is to make the rivet head flat and without the
slight oval shape they normally have.
John D.
---
| | - The Matronics RV-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
| Back to top |
|
|
|
|
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 vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
