New Information On MH 370

If the B777 was really in an emergency with no power to transmit they would have activated the 406 MHz ELT and detected by satellite anywhere in th world.

José

Yeah. You are assuming that the airplane was so equipped. Not all are.
 
TCAS is in no stretch of the imagination suitable for an aireal intercept and furthermore does not function with the Mode S transponder turned off.
How about "ADS-B In"? Will the CDTI still display traffic if the mode S transponder is OFF/STBY? I understand they are separate systems. Could the target plane's "ADS-B OUT" be interrogated by a hand-held transmitter without its position information?

dtuuri
 
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Interesting....

The FAA forces us GA owners to install a remote ELT switch within reach of the pilot and the big iron gets exempt..... Go figure...:mad2::mad2::rolleyes:


FAA doesn't require it if the ELT manufacturer doesn't. Not sure where you're getting this.
 
How about "ADS-B In"? Will the CDTI still display traffic if the mode S transponder is OFF/STBY? I understand they are separate systems. Could the target plane's "ADS-B OUT" be interrogated by a hand-held transmitter without sending position information?

I doubt it's possible to have ADS-B Out off while having ADS-B In on - But that's easily solved with an iPad and one of the various portable receivers.

Also, ADS-B Out does not need to be "interrogated" like a transponder. It's a passive system that transmits continuously.
 
I doubt it's possible to have ADS-B Out off while having ADS-B In on - But that's easily solved with an iPad and one of the various portable receivers.

Also, ADS-B Out does not need to be "interrogated" like a transponder. It's a passive system that transmits continuously.

You sure about that?
 
I doubt it's possible to have ADS-B Out off while having ADS-B In on - But that's easily solved with an iPad and one of the various portable receivers.

Also, ADS-B Out does not need to be "interrogated" like a transponder. It's a passive system that transmits continuously.

Help me out here. According to this:
The datalink transmitter that most aircraft will use is a Mode S transponder, using a feature called “Extended Squitter”. The Mode S transponder with Extended Squitter is the international standard for ADS-B output.​
If the TCAS/Mode S is in STBY, it would seem to me to shut down ADS-B Out, no? Since it transmits via a transponder, I reason it needs to be interrogated first. In fact, I thought one advantage of ADS-B is to reduce the workload of the transponder by minimizing the number of replies it needs to make.

dtuuri
 
How about "ADS-B In"? Will the CDTI still display traffic if the mode S transponder is OFF/STBY? ...

You know you've got me there. I didn't start working on triple sevens until 1995 and to be honest I have no idea what a CDTI is :dunno:
 
FAA doesn't require it if the ELT manufacturer doesn't. Not sure where you're getting this.

I bet it's a requirement of the particular TSO that newer ELTs have to meet.
 
I doubt it's possible to have ADS-B Out off while having ADS-B In on - But that's easily solved with an iPad and one of the various portable receivers.

Also, ADS-B Out does not need to be "interrogated" like a transponder. It's a passive system that transmits continuously.

See page 9, "Automatic" vs. "Broadcast": http://www.boeing.com/commercial/aeromagazine/articles/qtr_02_10/pdfs/AERO_Q2-10_article02.pdf

Are they speaking out of both sides of the mouth, so to speak?

dtuuri
 
Help me out here. According to this:
The datalink transmitter that most aircraft will use is a Mode S transponder, using a feature called “Extended Squitter”. The Mode S transponder with Extended Squitter is the international standard for ADS-B output.​
If the TCAS/Mode S is in STBY, it would seem to me to shut down ADS-B Out, no? Since it transmits via a transponder, I reason it needs to be interrogated first. In fact, I thought one advantage of ADS-B is to reduce the workload of the transponder by minimizing the number of replies it needs to make.

Yes, if you shut down the Mode S txp and that's what your plane transmits through, your ADS-B Out is off. Singapore didn't shut down their transponder, though.

My understanding is that ADS-B Out does transmit continuously, and I found a reference last night that verified that before I posted that last night. Realize that even "continuous" (1 Hz?) transmissions could make transponders make less replies in a busy area - With the current system you'd have not only ATC radar, but also every TCAS-equipped airplane in the vicinity interrogating you.
 
See page 9, "Automatic" vs. "Broadcast": http://www.boeing.com/commercial/aeromagazine/articles/qtr_02_10/pdfs/AERO_Q2-10_article02.pdf

Are they speaking out of both sides of the mouth, so to speak?

Not sure what you were referring to on page 13? :dunno:

However, I think I know your source of confusion: They talk about Mode S transponders being interrogated. However, the key word in that paragraph is "Current" - IE, a Mode S (or C) transponder *without* Extended Squitter (ADS-B Out). So, for example, even though I do not have an ADS-B capable transponder, I will show up on the CDTI in an ADS-B equipped plane, as long as my transponder is being *interrogated* by ATC radar. The ADS-B Ground stations will transmit the position of my plane.

Two key takeaways from this document that support what we're saying with regards to a potential intercept here are:

1) Range of ADS-B is over 100 miles. (Plenty more than the 55 or so I'd previously said would be needed to execute this as I'm visualizing it)
2) ADS-B transmits data at a rate ≥1 Hz without any interrogation.
 
BTW, I saw a tweet from a local TV station saying that the Malaysian transport minister announced that "new information" indicates that the flight ended in the Indian Ocean.

Retraction/Debunk in 3,2,1...

I hope we find a piece of airplane soon.
 
he said it was based on British satellite data...so who knows
 
FAA doesn't require it if the ELT manufacturer doesn't. Not sure where you're getting this.

I don't know the exact reg,,, but..

There were two of us experimentals that got inspected at the same time back in 2004.. Mine had the remote ELT activation switch in the panel.... His didn't.. According to the DAR he would not issue a airworthness cert till it was installed..

Mine is right under the T&B....
 

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Yes, if you shut down the Mode S txp and that's what your plane transmits through, your ADS-B Out is off. Singapore didn't shut down their transponder, though.
My point is MH370 could have shut down their Mode S, so it wouldn't broadcast it's proximity to Singapore's ADS-B In.

My understanding is that ADS-B Out does transmit continuously, and I found a reference last night that verified that before I posted that last night. Realize that even "continuous" (1 Hz?) transmissions could make transponders make less replies in a busy area - With the current system you'd have not only ATC radar, but also every TCAS-equipped airplane in the vicinity interrogating you.
If true, no need for any supplementary hand-held device to interrogate SQ68 to see where it is.

Not sure what you were referring to on page 13? :dunno:
Page #9, for you; page #13 for Silvaire.

However, I think I know your source of confusion: They talk about Mode S transponders being interrogated. However, the key word in that paragraph is "Current" - IE, a Mode S (or C) transponder *without* Extended Squitter (ADS-B Out). So, for example, even though I do not have an ADS-B capable transponder, I will show up on the CDTI in an ADS-B equipped plane, as long as my transponder is being *interrogated* by ATC radar. The ADS-B Ground stations will transmit the position of my plane.

Two key takeaways from this document that support what we're saying with regards to a potential intercept here are:

1) Range of ADS-B is over 100 miles. (Plenty more than the 55 or so I'd previously said would be needed to execute this as I'm visualizing it)
2) ADS-B transmits data at a rate ≥1 Hz without any interrogation.
Ok, that all makes sense now.

BTW, I saw a tweet from a local TV station saying that the Malaysian transport minister announced that "new information" indicates that the flight ended in the Indian Ocean.
Ah, that must be a reference to the woman who spotted a plane in the water: http://www.dailymail.co.uk/news/art...ter-near-Andaman-Islands-day-disappeared.html
EDIT: Oh, I see that's a different "new information".


Here we go: http://fox6now.com/2014/03/24/investigators-say-malaysia-airlines-flight-370-ended-in-indian-ocean/

How odd that the Chinese seem to think that they've definitely found it, but our P-8 could detect nothing. I wonder if this is just another political ass-covering maneuver.
I'm not holding my breath. :rolleyes:

dtuuri
 
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I am really beginning to wonder who was in that plane, and, or, what was in the cargo hold...:dunno::confused:

Yeah, and why the hell they were in the southern Indian Ocean to begin with. Even if the plane is/was found there, we still have a helluva mystery. I hope that if they've found the plane, they can find the CVR/FDR.
 
I read online (so probably not accurate) the CVR only holds the last 2 hours . Hopefully it's much longer than that.

from
http://en.wikipedia.org/wiki/Cockpit_voice_recorder


A standard CVR is capable of recording 4 channels of audio data for a period of 2 hours. The original requirement was for a CVR to record for 30 minutes, but this has been found to be insufficient in many cases, significant parts of the audio data needed for a subsequent investigation having occurred more than 30 minutes before the end of the recording.
 
Yeah, and why the hell they were in the southern Indian Ocean to begin with. Even if the plane is/was found there, we still have a helluva mystery. I hope that if they've found the plane, they can find the CVR/FDR.

My guess - a modern Flying Dutchman. Even if this were some kind of suicide, and I'm not saying it was, it would have been one of the pilots, not both, so it's unlikely he would have spent the last five hours carrying on a conversation with himself.

Another point, even knowing for certain that it is in the Indian Ocean does not guarantee that we'll ever find it. The ULB is already more than half way through it's useful life meaning they only have maybe two weeks left to locate it.
 
Actual FAA ruling on ELT requirement for commercial flight:

http://www.ntsb.gov/news/events/2012/GA_Search_Rescue/presentations/Smith.pdf

And like for GA ELT is required for Air Transport planes as well.

José

Ok, I'll put this as simply as possible for you so that there is some slight chance you might be able to comprehend it - THERE IS NO SWITCH LIKE THAT ON ANY 777 THAT I HAVE EVER FLOWN OR SEEN. So there is no way to activate something that does not exist. Your unfamiliarity with the 777 is glaringly obvious the more you bring this up.
 
Interesting....

The FAA forces us GA owners to install a remote ELT switch within reach of the pilot and the big iron gets exempt..... Go figure...:mad2::mad2::rolleyes:

They are not exempt. The newer ELTs have to meet TSO C91A or C126 and both require a remote switch location accessible to the pilot. The installation instructions for an ELT will specify the switch needed and where it has to be located. You don't have a choice to modify the installation instructions and still meet the legal requirement. All new installations have to meet C91A or C126 so they'll have remote switches, big iron included.
 
All new installations have to meet C91A or C126 so they'll have remote switches, big iron included.

Maybe so, but I sure as hell don't know where that is on a 777 and I have been flying them for 17 years.
 
Ok, I'll put this as simply as possible for you so that there is some slight chance you might be able to comprehend it - THERE IS NO SWITCH LIKE THAT ON ANY 777 THAT I HAVE EVER FLOWN OR SEEN. So there is no way to activate something that does not exist. Your unfamiliarity with the 777 is glaringly obvious the more you bring this up.

Public Law
Title 49 US Code 44712 - Emergency
Locator Transmitters

(a) Installation. – An emergency locator transmitter
must be installed on a fixed-wing powered civil
aircraft for use in air commerce.
(b) and (c) Non-applications.
(d) Compliance – ELT transmits on 121.5/243 or 406


So the B777s you have been flying are in violation of the above. So on your flight training how would you and 200 passengers are supposed to be found after a crash? So if I crash on my Mooney I have better chance to be found.

Check with your flight instructor on this. ELT switch operation described by Boeing (at the page bottom)
http://quizlet.com/11368500/boeing-777-fcom-1-airplane-general-flash-cards/

Here is how the switch looks like:

https://www.google.com/search?q=B77...Altitude%2BChanges%2Farticle34524.htm;761;407

José
 
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They're saying it's in the Indian Ocean. Prayers to the families, I hope they can find some closure.
 
Public Law
Title 49 US Code 44712 - Emergency
Locator Transmitters

(a) Installation. – An emergency locator transmitter
must be installed on a fixed-wing powered civil
aircraft for use in air commerce.
(b) and (c) Non-applications.
(d) Compliance – ELT transmits on 121.5/243 or 406


So the B777s you have been flying are in violation of the above. So on your flight training how would you and 200 passengers are supposed to be found after a crash? So if I crash on my Mooney I have better chance to be found.

Check with your flight instructor on this. ELT switch operation described by Boeing (at the page bottom)
http://quizlet.com/11368500/boeing-777-fcom-1-airplane-general-flash-cards/

Here is how the switch looks like:

https://www.google.com/search?q=B77...Altitude%2BChanges%2Farticle34524.htm;761;407

José

I'm in no position to say that it's accurate, but here's a nifty click-and-view of a 777 flight deck (don't just hover, click):

http://meriweather.com/flightdeck/777/deck-777.html

I looked, but can't find an ELT switch.
 
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All of the real triple seven pilots step aside and allow the Google armchair folks to take over. :rolleyes:
 
Actual FAA ruling on ELT requirement for commercial flight:

http://www.ntsb.gov/news/events/2012/GA_Search_Rescue/presentations/Smith.pdf

And like for GA ELT is required for Air Transport planes as well.

José

You know, it is really hard to get good context from a power point presentation like that.

I will tell you what I KNOW for a fact.

91.207(f)(2) exempts aircraft while engaged in scheduled service by scheduled air carriers.

Some aircraft are equipped with ELT's, some are not. Showing a picture of an ELT arming switch, in and of itself, is not proof that all aircraft are so equipped.

There are several 121 pilots in this thread that are telling you that an ELT is NOT required on 121 flights.

Given the above information, you are free to believe what you want, but what you believe may not reflect reality.
 
They are not exempt. The newer ELTs have to meet TSO C91A or C126 and both require a remote switch location accessible to the pilot. The installation instructions for an ELT will specify the switch needed and where it has to be located. You don't have a choice to modify the installation instructions and still meet the legal requirement. All new installations have to meet C91A or C126 so they'll have remote switches, big iron included.

Uh, no. :no:
 
I'm in no position to say that it's accurate, but here's a nifty click-and-view of a 777 flight deck:

http://meriweather.com/flightdeck/777/deck-777.html

I looked, but can't find an ELT switch.

You know, it is really hard to get good context from a power point presentation like that.

I will tell you what I KNOW for a fact.

91.207(f)(2) exempts aircraft while engaged in scheduled service by scheduled air carriers.

Some aircraft are equipped with ELT's, some are not. Showing a picture of an ELT arming switch, in and of itself, is not proof that all aircraft are so equipped.

There are several 121 pilots in this thread that are telling you that an ELT is NOT required on 121 flights.

Given the above information, you are free to believe what you want, but what you believe may not reflect reality.

Agreed. I haven't flown the 777 but the other types (727, 757, 767 and A320) I've never seen a cockpit switch for an ELT.

I looked in the A320 FCOM and found nothing. I then looked in the MEL and found this:

25-65-04 Emergency Locator Transmitter (ELT)
Ident.: MI-25-65-00008578.0001001 / 26 DEC 12
Applicable to: ALL
25-65-04A
Repair interval Nbr installed Nbr required Placard
– 2 2 No
Both must be operative for extended overwater operations.
25-65-04B
Repair interval Nbr installed Nbr required Placard
C 2 1 No
Portable ELT may be inoperative or not installed provided that extended overwater operations is not conducted.


In our liferafts there are portable ELT's as part of the survival kit, but not one installed on the airplane.
 
Public Law
Title 49 US Code 44712 - Emergency
Locator Transmitters

(a) Installation. – An emergency locator transmitter
must be installed on a fixed-wing powered civil
aircraft for use in air commerce.
(b) and (c) Non-applications.
(d) Compliance – ELT transmits on 121.5/243 or 406


So the B777s you have been flying are in violation of the above. So on your flight training how would you and 200 passengers are supposed to be found after a crash? So if I crash on my Mooney I have better chance to be found.

Check with your flight instructor on this. ELT switch operation described by Boeing (at the page bottom)
http://quizlet.com/11368500/boeing-777-fcom-1-airplane-general-flash-cards/

Here is how the switch looks like:

https://www.google.com/search?q=B77...Altitude%2BChanges%2Farticle34524.htm;761;407

José


Page 6 of YOUR OWN source material under EXEMPTIONS lists aircraft with a maximum payload capacity of more than 18,000 pounds that are used in air transportation as being EXEMPT from this rule !
How much more do you want to be wrong about this ? What are you going to show me next - a stealth switch ??????????
 
Here is a link to a UK AAIB report of an electrical fire that occurred on 777 while pushing back from the gate. It is of note that this fire began from arcing but then also extinguished itself without any crew intervention. Of special interest is section 1 page 48 where it mentions NINE other fires occurring on 777s. Also I found it interesting on page 96 section 2.6 where it talks about the increased risk of these types of fires in hot humid climates.

http://www.aaib.gov.uk/publications/formal_reports/2_2009_n786ua/n786ua_report_sections.cfm
 

I only meant to say that if an ELT is required to be installed, it has to have a remote switch accessible to the pilot in order to meet the requirements of TSO C91A or C126. I'll go with what comments the 121pilots make as to whether their particular operation requires an ELT be installed.
 
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