Reply Fri 14 Mar, 2014 08:41 am
...pilots or anyone else can TURN OFF the transponder in an aircraft while it is in flight, so that ground control loses one of the ways of tracking the plane???

Why is that switch there in the cockpit...and so easily accessible?
 
Lordyaswas
 
  2  
Reply Fri 14 Mar, 2014 08:43 am
@Frank Apisa,
So that's what it does!
0 Replies
 
DarkCrow
 
  2  
Reply Fri 14 Mar, 2014 09:11 am
@Frank Apisa,
The Transponder Head(s)(IFF) in most aircraft I've flown (737-200,B52G, T-37) is around/near other NAV-COM heads in front or to the close side of the P/CP. Not easily accessed by any other person without leaning in/over the "drivers". If I was ever asked at gunpoint to turn it off, I might accidentally reset it to 7700 and Ident.(highlight myself to ARTCC.) What happens then is in the hands of (insert diety here).
Frank Apisa
 
  1  
Reply Fri 14 Mar, 2014 09:22 am
@DarkCrow,
DarkCrow wrote:

The Transponder Head(s)(IFF) in most aircraft I've flown (737-200,B52G, T-37) is around/near other NAV-COM heads in front or to the close side of the P/CP. Not easily accessed by any other person without leaning in/over the "drivers". If I was ever asked at gunpoint to turn it off, I might accidentally reset it to 7700 and Ident.(highlight myself to ARTCC.) What happens then is in the hands of (insert diety here).


Thank you, DC.

But why is it there at all?

What circumstances might there be that would be made better by having the pilot turn it off?

Seems to me that only reason a pilot would turn it off...is if ordered to do so by a hijacker. Wouldn't it be better if that were not an option?

DarkCrow
 
  2  
Reply Fri 14 Mar, 2014 09:32 am
@Frank Apisa,
Are you asking why is it under the control of the crew? Like maybe it should be automatically ON when the aircraft is powered on and automatically change settings during Taxi, Take-off and Cruise. A fully automated system may be in the works in the future. I do not know, but its an interesting question. Small aircraft do not have the capacity for fully automated avionics. but large commercial A/C is a different story. Since many large A/C are fly by wire or semi-FBW, automating other aspects may make sense. Weight and price may be restrictions that can be overcome if safety is paramount. I like the idea of an emergency automated satellite tracking system, but we are years from that. And to get compliance across all current operational A/C owners is tricky unless someone else pays for it.
0 Replies
 
rosborne979
 
  2  
Reply Fri 14 Mar, 2014 12:58 pm
@Frank Apisa,
Frank Apisa wrote:

...pilots or anyone else can TURN OFF the transponder in an aircraft while it is in flight, so that ground control loses one of the ways of tracking the plane???

Why is that switch there in the cockpit...and so easily accessible?

Found this on one of the news sites...

"Q. Why would you turn off a transponder during a normal flight?
There could be several reasons. One reason could be when airplanes get close to each other (perhaps they are approaching an airport). Air traffic controllers may then request pilots to turn the transponders off or to standby. Also, if the transponder is sending faulty information, the pilot might want to turn it off. Planes are still visible on primary radar until they get below the radar's coverage ability."

Obviously this doesn't explain why it was turned off in the case of the missing airliner. But it does explain why the switch is there and accessible to the pilots.
0 Replies
 
rosborne979
 
  1  
Reply Fri 14 Mar, 2014 01:11 pm
Interesting speculation from an expert...

http://hereandnow.wbur.org/2014/03/12/mystery-malaysia-plane

Quote:
Transcript

ROBIN YOUNG, HOST:

It's HERE AND NOW.

All right. Roger that. According to Malaysian officials speaking today in Beijing to relatives of passengers, those were the last words heard from Malaysia Airlines flight 370 before it lost communication five days ago. A pilot responding to Malaysian air traffic controllers telling him the plane was entering Vietnamese airspace. Confusion continues in the search today. Vietnamese officials briefly suspended their participation in the search, angered at conflicting reports as to whether the plane reversed course before disappearing.

Mary Schiavo is former inspector general at the Department of Transportation. She's also litigated on behalf of scores of plane crash victims families, and she joins us now. Mary, welcome back to HERE AND NOW.

MARY SCHIAVO: Thank you. Good to be with you.

YOUNG: And what about this new information, the last communication? Does that tell you anything?

SCHIAVO: Well, it just says that at that point, the flight was very normal. All right. Roger that. That's pretty much, you know, pilot lingo. Not reporting any problems. Proceeding on with your flight as, pretty much, you know, literally thousands of flights a day.

YOUNG: Well, it angered people, though, at this apparently very hostile press conference with Malaysian authorities because they had said that the air traffic lost contact at 1:20 AM. on the east side of the peninsula. But now they're saying they picked up words on military radar at 2:40 AM. I mean, and then there's the confusion as to whether or not Malaysian officials said that the plane had done that whip turn and reversed course. The Malaysian official who said that now said that's not true. Your thoughts on all of that.

SCHIAVO: Well, I think the anger is directed, and should be directed, you know, to the Malaysian government and the people who are putting out this information and then retracting the information. They simply don't understand that families of victims of air crashes desperately want information. They hang on any piece of information, and everything about the crash becomes incredibly important. Some of the best investigators that have ever worked with me in cases have been people who have lost someone in a crash because every detail becomes very important.

And I think that's why there is just so much anger because they're entitled to information. If it was in the U.S., the victims - there's a victims protection act, and it says they're entitled to daily briefings. They're entitled to know what the government knows. And people in other countries don't have those rights.

YOUNG: Well, but the point is, what does the government know? So grade the press conferences, if you will, the investigation. Is it fair if they are giving - if they're trying to keep families updated, if the information changes, you know, they have to go with the changes.

SCHIAVO: Well, but I think common sense can tell people that it's not ringing true. For example, you know, first, they said there was indication that it turned back. There was also a report that Vietnamese air traffic control asked another plane to see if they could contact it. The significance of that is sometimes if you lose communications in your antennas or you lose the ability to have your transponder on, other planes in the area can communicate because you have more short range ability communicating. And the plane said that they got very staticy(ph), garbled transmission from the plane.

And then, of course, there was the indication, now retracted, that it had turned back and yet this was after days - at least two days of searching. And, you know, nations from around the world and ships and planes searching in an area that now the Malaysian authorities say, well, I guess, we didn't ever - we never said that. So the anger is well deserved.

And at this point, you have to wonder about their other theories. They had a press conference and they had three or four different theories that they said they're proceeding under. Most of them center around terror or intentional downing, terror suicide. But those don't make sense when you look at their actions.

First of all, if the plane was going on to Vietnamese airspace and it had lost communications, no pilot in a post-9/11 world would do that. Why? Because it would be assumed, if you're not communicating, that there's something wrong. You could be hijacked. You might not - the pilot's not at the controls. Turning back would make complete sense if you were having a mechanical problem or communications problem. And so when they say they turned back, that made sense to people.

Now, they say they, you know, that might have been mistaken. Well, that doesn't ring true. And I think at this point, common sense has to rule out, and they have to say, look, what most likely happened to the plane?

YOUNG: Well, Mary, with all your expertise in this, there has been so much educated speculation - terrorism, a bomb, pilot suicide, some sort of catastrophic mechanical failure. What are you thinking today?

SCHIAVO: Well, my thoughts actually, you know, I rely on some of the brightest aerospace minds in the world - none other than Boeing. Boeing put out a warning back in August, and it said that the 777 had a problem with fuselage cracking.

In particular, it was cracking around the satellite antennas and the communications antennas on the plane. And if that that was the case - for example on this one, it had just been on maintenance 10 days ago, and they had said something very curious. They said they had - it had been in maintenance but they had more maintenance to do and it would go back in June. So I wonder what they did and did not get done.


So if this plane had a problem and it had cracking or some sort of a rapid decompression and lost the ability to communicate to transponder, it would make perfect sense. What would a sensible pilot do? Well, you'd never go into another country's airspace if you'd lost communications and had a rapid decompression. You'd turn around and try to get your plane back home.

And if Malaysia thought it had been hijacked and there was someone else at the controls, why did they allow this plane not only to enter its airspace again - return - but fly for two hours across its country and then head on to Indonesia? That doesn't make sense either. So the most sensible - given what we know, which isn't very much - is that it had a rapid decompression, it lost the ability to communicate with its transponder, not that it was turned off voluntarily or hijacked, but the signal was no longer being sent out.

And then they continued on. Why? Because that's what's the 777 does. The 777 is a really pretty cool plane, so is the Airbus 340 - I don't mean to slight Airbus. But the 777 has a system like the Airbus where when something goes wrong, the plane itself will start shutting down unnecessary systems. It shuts down unnecessary communication systems. It shuts down everything, basically. It will spool down system by system until what's left, control surfaces - left-right, up-down, and the engines. The 777 will fight to save itself. And I think that's what it did.

YOUNG: Yeah. Well - but - we only have about a minute left, but does that mean it might have - shut down, let's say, oxygen?

SCHIAVO: Yes. I'm afraid that it might have done that.
And you don't have oxygen forever, by the way. The passengers' oxygen canisters won't last for the length of the fuel tank. They might have had 30 minutes. The pilots, if they hadn't gotten their oxygen masks on in 30 seconds at 35,000 feet, they would have gone unconscious, maybe as long as a minute if they'd had good training. But oxygen would be the key, and they would not have - as much oxygen as they would have fuel to continue the flight.

YOUNG: OK. A terrible, terrible, terrible speculation but an educated...

SCHIAVO: Terrible.

YOUNG: ...assumptions here. But we are still waiting to learn more. Mary Schiavo, aviation lawyer, author of "Flying Blind, Flying Safe" and former government official. Thanks so much for weighing in today.

SCHIAVO: Thank you. Thank you. Condolences to the families.

YOUNG: You're listening to HERE AND NOW. Transcript provided by NPR, Copyright NPR.

DarkCrow
 
  1  
Reply Fri 14 Mar, 2014 01:59 pm
@rosborne979,
Rapid "D" is a possibility. The 777 automatically shutting down systems when there is no human intervention is interesting. Most other A/C would continue flight until fuel is expended assuming no other failures. What a mess. Still..ones asks, where are the emergency beacons from the two flight recorders.
rosborne979
 
  4  
Reply Fri 14 Mar, 2014 02:03 pm
@DarkCrow,
DarkCrow wrote:
Still..ones asks, where are the emergency beacons from the two flight recorders.

Probably under a whole lot of water, very far from where anyone is looking.
0 Replies
 
tsarstepan
 
  1  
Reply Fri 14 Mar, 2014 02:09 pm
@Frank Apisa,
Frank Apisa wrote:

Why is that switch there in the cockpit...and so easily accessible?

Here's an uneducated toss. Assuming the transponder is electrically powered, what does the pilot need to do to protect other vital electronics near the transponder when ... say it has a possible short or electrical fire (which is a possibility from faulty wiring, etc...). Maybe the transponder was broken or damaged and it was affecting (effecting?) another system? Maybe the pilot needed to turn the transponder off before it caused further damage to the other systems (therefore a need for a switch to turn off the electrical flow to the area ... a manual fuse box if you will).
0 Replies
 
Frank Apisa
 
  1  
Reply Fri 14 Mar, 2014 02:13 pm
@Frank Apisa,
As regards my actual question, none of this still makes any sense to me.

Gas stations and buses often have notices up that the attendants and drivers CANNOT access the money. They cannot get at it. That makes the attendants and drivers safer...because there is no way they can get at it.

If a hijacker (or renegade pilot) knew there was no way to turn the transponder off...that would not be one of the items on the table.

Unless there was a catastrophic malfunction...with all systems going dead...the transponder would have continued to transmit even if the plane were diverted because of a hijacker or renegade pilot. The fact that it can just be turned off...makes no sense.

Unless I am missing something. Just wondering if anyone has any ideas on what that "something" might be?
tsarstepan
 
  1  
Reply Fri 14 Mar, 2014 02:15 pm
@Frank Apisa,
Look up one post. I try to touch on your thread's actual question. Emphasis on the try.
Frank Apisa
 
  1  
Reply Fri 14 Mar, 2014 02:19 pm
@tsarstepan,
tsarstepan wrote:

Look up one post. I try to touch on your thread's actual question. Emphasis on the try.


Missed that, Tsar...we were cross posting.

I get what you are saying...but every transponder has the OFF feature...and there cannot possibly be enough situations like you mentioned to require that particular piece of equipment (one of many) to need that function.

Well...I have read up as much as I can...and Googled the topic...and it still mystifies me.

But...I am often mystified by a light switch.
0 Replies
 
rosborne979
 
  2  
Reply Fri 14 Mar, 2014 07:15 pm
Didn't anyone have their cell phone on in that plane?
Frank Apisa
 
  1  
Reply Sat 15 Mar, 2014 06:41 am
@rosborne979,
rosborne979 wrote:

Didn't anyone have their cell phone on in that plane?


That really is amazing...and although I have heard some comments in news reports about "why can the transponder be disengaged?"...I have not heard any comments about the cell phones.

Gotta wonder if it was a hijacking...and that everyone except the hijackers were rendered unconscious somehow...perhaps a gas attack of some sort...with the hijackers (or hijacker) having a mask.

This is quite a mystery...and it appears all people love mysteries.
rosborne979
 
  2  
Reply Sat 15 Mar, 2014 08:31 pm
@Frank Apisa,
I'm not sure how far call phone towers reach. Maybe while they were over the water between Malaysia and Viet Nam it was too far from any tower.

But if the plane really did fly back over a land mass of any type, then you would have thought cell phone towers would have picked up activity from the phones even if the passengers were unconscious.

I love a good mystery too (just sad that it has to be a missing plane), but a lot of the mystery in this event comes from radar "rumors" being reported by various south-east asian countries with "unspecified" military radar capabilities.

If it weren't for the radar rumors, we would just assume that the flight had a catastrophic structural failure at altitude and broke up. That alone would account for everything... except the radar rumors.
oralloy
 
  0  
Reply Sun 16 Mar, 2014 12:09 am
@rosborne979,
rosborne979 wrote:
If it weren't for the radar rumors, we would just assume that the flight had a catastrophic structural failure at altitude and broke up. That alone would account for everything... except the radar rumors.

The fact that the plane pinged satellites for four or five hours after it "disappeared" is pretty significant.

Also, if the plane broke up at altitude in the area where it fell off the grid, there would be a large debris field that would have been easy to spot.
rosborne979
 
  2  
Reply Sun 16 Mar, 2014 10:41 am
@oralloy,
oralloy wrote:
The fact that the plane pinged satellites for four or five hours after it "disappeared" is pretty significant.

I'm not dismissing this point completely, but I'm suspicious of claims like this because I haven't seen enough detail on how this pinging is done or recorded. For instance, I don't know if the "pinging" mechanism has some level of battery backup and might be pinging for many hours even after a crash. I would just need to hear more detail on how this "pinging" is done and verified before I would feel completely confident in it.
oralloy wrote:
Also, if the plane broke up at altitude in the area where it fell off the grid, there would be a large debris field that would have been easy to spot.

The experts I have read say that a plane breaking up at 35k feet would leave such a dispersed field of small debris (especially over an ocean, where most items sink) that they would expect to find nothing. But I don't know the accuracy of this myself, I'm just going by what I've read from a few "experts". And I don't trust all the "experts" either, there are too many talking heads out there trying to grab some limelight and I can't tell which ones are which in all cases.
0 Replies
 
Wilso
 
  3  
Reply Fri 21 Mar, 2014 02:20 am
I think it's about that everyone admitted that nobody has got a ******* clue what happened to this plane. Until some evidence emerges, all the talking heads, the experts, and Malaysia and the airline, are just talking out their arses.
0 Replies
 
gollum
 
  1  
Reply Sun 23 Mar, 2014 12:32 pm
I read that the searchers are looking for apparent objects detected by satellites but are afraid that it (they) may sink before they can get to it.

If the object has floated for over one week, what would cause it now to sink?
 

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