Why do so many plane crashes have no real-time distress signal

Zaphod58
reply to post by Visitor2012

 

And if there is a sudden power failure between sendings? How are you going to ensure the data is sent if the aircraft explodes or breaks up suddenly?

The black box doesn't send anything to a satellite. It sends out a radio signal, which can be blocked by deep water or other factors.

edit on 3/8/2014 by Zaphod58 because: (no reason given)

I didn't say the black box can currently do it, I said we can DESIGN it to. It would take a microsecond to send that data, the military 'similarly' does it with their real time telemetry system for drones. ALL of the data for an entire flight can be stored on a thumb drive and sent via satellite, it's not a question of data size or bandwidth limitations. I have the flight data of several airline crashes sitting on my old hard drive, so it's not a question of technological limitations. Analogue is a very OLD system and digital data is very compact nowadays.

In fact, to hell with the black boxes all together! We have the technology to uplink REALTIME telemetry of select systems and flight parameters now. I'm not an aircraft systems designer, I'm just making a suggestion. There will always be special circumstances, but for the MAJORITY of air crashes this would be of great help.

So when a plane crashes in the mountains, the NTSB can simply download the flight telemetry from, let's say American Airlines company servers, and get to work immediately. Why are we still searching for needles in haystacks using valuable Search and Rescue people and hardware when we can configure an ipad to do this task? ( sort of kidding about the ipad...sort of)

reply to post by Visitor2012


As you pointed out ACARS and other systems do that to an extent already. It's how they know where to start looking.

There is always a need for a physical backup. Those cases like this one can be very important to find the cause.

gardener
I mean, if in this day and age officials actually wanted to know what happened to a plane right before it went down, just as thousands if not millions of homes already have internet-based security monitoring, don't control towers have a permanent ear to everything that is said in the cockpit (and perhaps everything that is seen from their view)?

As others have said, in some cases there is a data stream sent to headquarters, certainly on newer aircraft. On older aircraft, not so much unless it's been upgraded. But you can even see some history of the Malaysia aircraft up until the time contact was lost, like during the last 5 minutes it continued it's climb from 30,000 to 35,000 feet:

flightaware.com...

I'm completely guessing here but I suspect that's from transponder data transmitted to air traffic control or something. The airline headquarters would have more data if the aircraft is the type that sends a continuous stream of maintenance data, which I don't know if this 777 did that or not, but even if it did, I wouldn't expect the information to be made available to the public immediately, if ever, though I'm sure it would be provided to crash investigators.

Bedlam
These days, you'd think that they could send a real-time data stream back to the head shed, with all the data that's going to the black box and more. Like in-cockpit video and audio, maybe some camera feeds of the control surfaces and the like.

Technologically it's possible of course as I'm sure you know.

I vaguely seem to recall reading something about such a proposal where the pilot union objected to being "spied on" in the cockpit.

More recently I read a post by someone claiming to be an international route commercial pilot saying he would sometimes get "serviced" by female flight crew members, during his rest period.

It wasn't exactly clear whether these services were performed in the cockpit or elsewhere but I'm sure he wouldn't have wanted them on video, that is if he wasn't making it up.

Some ships have a ELT (Emergency Locator Transmitter) that is released on sinking.

Why can they not build a ELT type system that has a copy of the black box recording that can be released when the plane hits the water.
this could also have a built in GPS recorder that records the impact point making it the starting point for looking for the plane its self.

ANNED
Some ships have a ELT (Emergency Locator Transmitter) that is released on sinking.

Why can they not build a ELT type system that has a copy of the black box recording that can be released when the plane hits the water.
this could also have a built in GPS recorder that records the impact point making it the starting point for looking for the plane its self.

I have a feeling it's a matter of corporate economics.

reply to post by ANNED


Weight. Everything on a plane is about weight. The heavier something is, the less fuel, cargo, and passenger load you can carry. Even a few pounds can make a difference in some cases.