Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Technical Alternatives for Pitot Tubes?

Tech Log The very best in practical technical discussion on the web

Technical Alternatives for Pitot Tubes?

Old 9th Jan 2015, 13:50
  #121 (permalink)  
Join Date: Jan 2015
Location: derbyshire
Posts: 1
Air velocity correlation to aircraft location

When real time streaming of position and aircraft parameters becomes the norm over black box recording, there might be enough collective data to derive wind velocity maps. i.e. comparing GPS with working pitot static data in the majority of working planes travelling known routes. Apart from general meteo' data gathering uses, might that be useful for an aircraft with trouble to at least have a stab at estimating local wind from GPS as secondary / backup - or could there be a use for comparing the two sirspeed data sets if pitot dynamic (and possibly static) information is lost ?
jepprogs is offline  
Old 10th Jan 2015, 10:53
  #122 (permalink)  
Join Date: Apr 2004
Location: Planet Earth
Posts: 1,838
All good stuff but the 787 already has 'alternative' input airspeed based on corrected AOA input.

Seems like the answer, you're not going to block an AOA vane.
stilton is offline  
Old 10th Jan 2015, 21:16
  #123 (permalink)  
Join Date: Sep 2002
Location: La Belle Province
Posts: 2,127
Yes, you can. In fact there a whole bunch of ADs out thee regarding exactly that (at least one of the airbus ADs has an active thread I think)

What you do gain is having a (slightly) different means of sensing airspeed, but both are ultimately sensors, in the airflow, somewhere on the nose. That means the are still common cause failures that need to be addressed. The goal is to design those to be sufficiently improbable that a procedural solution is acceptable . i.e. pitch/power tables.
Mad (Flt) Scientist is offline  
Old 11th Jan 2015, 10:33
  #124 (permalink)  
Join Date: Jun 2009
Location: Bedford, UK
Age: 66
Posts: 1,228
Isn't there a role for the INS here, admittedly not for sensing AoA ? OK won't help avoid a stall but the initial developing downwards motion must be sensed by the INS and integrated up to give the speed? Could be that today's clever data fusion technology mean that currently the output is potentially contaminated by bad ADR data but the inertial calculations over a short period would be good wouldn't they?
Mr Optimistic is offline  
Old 12th Jan 2015, 12:26
  #125 (permalink)  
Join Date: Apr 2004
Location: Planet Earth
Posts: 1,838
Must have missed that MadScientist.

Do you know of an incident where both AOA vanes stopped working ?
stilton is offline  
Old 13th Jan 2015, 17:58
  #126 (permalink)  
Join Date: Sep 2002
Location: La Belle Province
Posts: 2,127
XL Airways A320, 2 of 3 AOA sensors froze.

The values of the n 1 and 2 local angles of attack recorded by the SSFDR remained fixed from FL 320 until the impact with the surface of the sea. It was not possible to determine the evolution of the value of the n 3 local angle of attack in the course of the flight, which is not recorded. The initiation of the stall warning, however, shows that angle of attack sensor n 3 was working at the end of the flight.
Mad (Flt) Scientist is offline  

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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.