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

Transponder Inoperative

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

Transponder Inoperative

Thread Tools
 
Search this Thread
 
Old 22nd Nov 2011, 10:55
  #1 (permalink)  
Thread Starter
 
Join Date: Apr 2010
Location: in the flight deck
Posts: 89
Likes: 0
Received 0 Likes on 0 Posts
Transponder Inoperative

Is there any MEL relief for a total failure of both transponder normally?

I know it should be in the MEL but i don't have a copy and im not working for another few more days.

I did use the "search" function but most talked about TCAS failure.

Not sure if it there a relief for it....no one can see you ...including ATC.

In a busy airport, how are they going to be able to cope with it?

What does it say in your MEL? no despatch?

Many thanks.

Neupielot is offline  
Old 22nd Nov 2011, 11:11
  #2 (permalink)  
 
Join Date: Aug 2009
Location: GPS L INVALID
Posts: 580
Likes: 0
Received 0 Likes on 0 Posts
Without an operating transponder you cannot enter RVSM airspace, the standard Boeing MMEL just states that you are good to go as long as 'operations do not require its use' and that 'prior to flight permission is obtained from the authority'... I remember waiting eight hours to have the transponder panel fixed rather than go fly without an operative transponder system...
STBYRUD is offline  
Old 22nd Nov 2011, 12:04
  #3 (permalink)  
 
Join Date: Mar 2001
Location: I wouldn't know.
Posts: 4,499
Likes: 0
Received 0 Likes on 0 Posts
Just checked my (european) 737 MEL for that.

Its a B item if both have failed (D if only one has failed), they may be inoperative provided that a) Operations do not require its use and b) prior to a flight approval is obtained from ATC facilities having jurisdiction over the planned route of flight.

That is pretty much an AOG without spelling it out, within europe at least it is impossible to get that approval for anything longer than a hop from one airport to another within the same city. And even that is questionable.

There are three notes to that however.

Note 1 says that an operative ATC Mode S transponder is defined as a transponder which can provide at least elementary surveillance capability (parameter downlink).

Note 2 says that Mode S altitude reporting is required for TCAS operation and if that doesn't work you have to check the MEL about TCAS inop as well.

Note 3 mentions that Mode S altitude reporting is required to enter RVSM and to check the RVSM MEL entry.

The definition in note 1 is pretty prohibitive as even the failure of a databus preventing elementary surveillance will be treated as an inop transponder.
Denti is offline  
Old 22nd Nov 2011, 15:52
  #4 (permalink)  
 
Join Date: Oct 2010
Location: Germany
Age: 47
Posts: 402
Likes: 0
Received 0 Likes on 0 Posts
basicly you will not get in europe an ifr clearance at all without any transponder so you would be stuck to vfr in uncontrolled airspace.

fo commecial operation its an factual AOG like denti says.
aerobat77 is offline  
Old 24th Nov 2011, 07:40
  #5 (permalink)  
Thread Starter
 
Join Date: Apr 2010
Location: in the flight deck
Posts: 89
Likes: 0
Received 0 Likes on 0 Posts
Thanks so much guys for your input.
Neupielot is offline  
Old 24th Nov 2011, 18:17
  #6 (permalink)  
 
Join Date: Sep 2009
Location: Bombay
Posts: 48
Likes: 0
Received 0 Likes on 0 Posts
was doing muscat riyadh flight....just after airborne both transponders failed....muscat put us in a hold over the sea and got us back to muscat, because uae will not except flights without a transponder....even after asking them to check once again, it was a complete no....landed back and grounded the aircraft till the spares arrived late at night and the flight departed with a 16 hour delay...
Speed Freak is offline  
Old 25th Nov 2011, 00:24
  #7 (permalink)  
 
Join Date: Sep 1998
Location: wherever
Age: 55
Posts: 1,616
Likes: 0
Received 0 Likes on 0 Posts
OPS 1.866
Transponder equipment
(a) An operator shall not operate an aeroplane unless it is equipped with:
1. a pressure altitude reporting SSR transponder; and
2. any other SSR transponder capability required for the route being flown.
FE Hoppy is offline  
Old 26th Nov 2011, 08:43
  #8 (permalink)  
Thread Starter
 
Join Date: Apr 2010
Location: in the flight deck
Posts: 89
Likes: 0
Received 0 Likes on 0 Posts
Transponder equipment
(a) An operator shall not operate an aeroplane unless it is equipped with:
1. a pressure altitude reporting SSR transponder; and
2. any other SSR transponder capability required for the route being flown.
For discussion purposes, "equipped" in this context, debatable ?

The aircraft is equipped with a transponder ( infact 2 transponders), just that they are now inop and therefore it is now MEL-ed. If its allowed in the MEL then it should be allowed to operate?

I think most countries just wont allow you in their airspace without an operating transponder.
Neupielot 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



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.