# Why Are We Still Looking For Black Boxes? **URL:** \ **Category:** Factual Questions\ **Created:** [June 4, 2009, 6:52pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730 "2009-06-04T18:52:59Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [June 4, 2009, 9:25pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/21 "2009-06-04T21:25:11Z")
> [@Bijou\_Drains](#): > > I believe most crashes are on land because that is where most flights are. Flights over oceans are not a big percent of flights. I think most crashes are on land because most crashes occur during takeoff or landing. ---
**Author:** ![yelimS](https://avatars.discourse-cdn.com/v4/letter/y/54ee81/32.png) [@yelimS](https://boards.straightdope.com/u/yelimS)\ **Post date:** [June 4, 2009, 9:28pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/22 "2009-06-04T21:28:07Z")
> [@CurtC](#): > > In a system like that, you’d be guaranteed to collect the vast majority of flight data, but also guaranteed to miss the most important bits. But couldn’t the system automatically start transmitting continuously in the event of the plane losing altitude (Except during regular landings)? Even if continuous streaming is a heavy load if applied to all flights at all times, it might not be for just a few incidents a year. ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [June 4, 2009, 9:31pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/23 "2009-06-04T21:31:28Z")
This is also an industry that is relatively resistant to change, at least when it comes to mandatory technology changes, because of the massive cost in retrofitting existing aircraft. Planes are designed to have service lives of 20 or 30 years, and a relatively small number of new planes enter service every year. In theory, it’s the older planes that are more at risk of a crash, though I don’t really know if the data actually indicates that. Requiring that technology like this becomes installed means that the airlines/flight operators would have to spend a bunch of money, and ticket prices for passengers/cost for cargo would go up, etc. Additionally, it wouldn’t be sufficient for just the FAA to require it; the entire worldwide aviation industry would have to agree to this, and there are currently 188 members of ICAO, not all of which could afford the data centres or aircraft upgrades either. I don’t have any numbers to support this, but in my readings of plane crashes and their investigations, there are very, very few cases where the black boxes cannot be found on land or in water. I am not an expert by any means, but I can’t even think of a case other than this one where that happened. They are designed to withstand impact, fires, high underwater pressures, and to emit radio signals for up to 30 days when disconnected from the aircraft. They are usually found, and this particular case is incredibly unusual in that no one has been able to detect them yet (which is why they are being considered lost - overflying planes should have been able to “hear” them). ---
**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\ **Post date:** [June 4, 2009, 9:37pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/24 "2009-06-04T21:37:23Z")
[QUOTE=Hyperelastic] Also, when will they start using black boxes that float? [/QUOTE] What would be the point? The data recorders are bolted to big non-floating chunks of airplane. ---
**Author:** ![DagNation](https://avatars.discourse-cdn.com/v4/letter/d/ee7513/32.png) [@DagNation](https://boards.straightdope.com/u/DagNation)\ **Post date:** [June 4, 2009, 9:38pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/25 "2009-06-04T21:38:03Z")
> [@Hyperelastic](#): > > Also, when will they start using black boxes that float? You stole my answer. What I was going to suggest is a bunch of airbags that are programmed to come out in series: 1 at the first sign of catastrophe 1 that will blow after a heat spike 1 that will blow with an impact \>X 1 that will blow after a time delay The reason I suggest all that is that it is likely that an airbag will get destroyed by puncture or fire shortly after the incident, but may have another chance to blow later and float up to the surface or bee seen easier. Also, add transponders to black boxes so there is some radio beacon to follow. Safety Dag;) ETA: add exploding bolts to seperate from large heavy chunk of metal. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [June 4, 2009, 9:44pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/26 "2009-06-04T21:44:58Z")
> [@gotpasswords](#): > > What would be the point? The data recorders are bolted to big non-floating chunks of airplane. Star Trek already figured this out a long time ago. You eject the box. It parachutes down with a flotation device and a GPS transponder. ---
**Author:** ![Sitnam](https://avatars.discourse-cdn.com/v4/letter/s/6a8cbe/32.png) [@Sitnam](https://boards.straightdope.com/u/Sitnam)\ **Post date:** [June 4, 2009, 9:45pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/27 "2009-06-04T21:45:47Z")
Maybe the atmospheric conditions that would bring down a 747 could possibly disrupt the stream of data at that relevant point. I still can’t recieve phone calls in the shop I work at. ---
**Author:** ![FORTRAN\_forever](https://avatars.discourse-cdn.com/v4/letter/f/f17d59/32.png) [@FORTRAN\_forever](https://boards.straightdope.com/u/FORTRAN_forever)\ **Post date:** [June 4, 2009, 10:12pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/28 "2009-06-04T22:12:32Z")
> [@Markxxx](#): > > I don’t buy the bandwidth is costly argument. The real argument is if I use the bandwidth for that I can’t sell the same bandwidth so Americans can have a second and third cellphone, another wireless Internet AND a GPS. Uhh - GPS units are receivers, not transmitters, so individual GPS units don’t use any bandwidth at all. It’s only the (24 or so?) GPS satellites (sp?) that actually transmit GPS signals - and they transmit the same signals regardless of the number of GPS units that are listening for them. ---
**Author:** ![FORTRAN\_forever](https://avatars.discourse-cdn.com/v4/letter/f/f17d59/32.png) [@FORTRAN\_forever](https://boards.straightdope.com/u/FORTRAN_forever)\ **Post date:** [June 4, 2009, 10:18pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/29 "2009-06-04T22:18:34Z")
> [@Magiver](#): > > Star Trek already figured this out a long time ago. You eject the box. It parachutes down with a flotation device and a GPS transponder. But if you eject the box (which presumably you do before the actual crash) you eliminate the possibility of ever collecting/retrieving any information after that point up to the actual point of impact. I was under the impression that last-instant data was important, as you want to know not only what initially caused the problem but what the sequents of events were afterwards. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [June 4, 2009, 10:31pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/30 "2009-06-04T22:31:21Z")
> [@FORTRAN\_forever](#): > > But if you eject the box (which presumably you do before the actual crash) you eliminate the possibility of ever collecting/retrieving any information after that point up to the actual point of impact. I was under the impression that last-instant data was important, as you want to know not only what initially caused the problem but what the sequents of events were afterwards. Not really a problem. If you’re decending at 32 feet per second squared it ejects. If all input to the box stops it ejects. If the pilot thinks it’s hopeless it is manually ejected. You don’t need to know the last second of data before impact, you need to know why the plane is no longer airworthy. ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [June 4, 2009, 10:36pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/31 "2009-06-04T22:36:32Z")
I’d rather the pilot work on saving the plane, than worry about ejecting the Flight Data Recorder. ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [June 4, 2009, 10:37pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/32 "2009-06-04T22:37:13Z")
Re: airbags That would require more space available in the plane for the recorders and the volume of airbags, and since every cubic inch of space is maximized in a plane, that’s not likely to happen. Re: ejecting the recorders Swissair 111’s recorders gave out 6 minutes prior to the plane hitting the water, so the events leading up to the impact and breakup were not recorded. Investigators had to reconstruct this period entirely from the physical evidence found in the pieces of the plane/bodies recovered from the sea, which took a lot longer and was very costly. Ejecting the recorders would result in this type of investigation all the time due to the loss of the final minutes of data, as **FORTRAN forever** points out. ---
**Author:** ![Chessic\_Sense](https://avatars.discourse-cdn.com/v4/letter/c/7c8e57/32.png) [@Chessic\_Sense](https://boards.straightdope.com/u/Chessic_Sense)\ **Post date:** [June 4, 2009, 10:43pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/33 "2009-06-04T22:43:58Z")
How about because we still find them? It’s almost always possible to find the black box. It’s only in rare instances like this week’s that they can’t be found. Personally, I think the fact that we use them at all is only 20% to find out what went wrong and 80% to satisfy the morbid curiosity of onlookers and help give closure to families of victims. I think the current system works just fine for the minimal amount of tangible good it does us. I’d rather not spend $billions improving a system so we can learn just a tad more about what went wrong on a tiny tiny fraction of flights. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [June 4, 2009, 10:49pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/34 "2009-06-04T22:49:21Z")
> [@Telemark](#): > > I’d rather the pilot work on saving the plane, than worry about ejecting the Flight Data Recorder. Doesn’t matter. As I pointed out, the box would eject under the conditions I listed. It would be nothing to add an ejection system and a small parachute. ---
**Author:** ![Animastryfe](https://avatars.discourse-cdn.com/v4/letter/a/8797f3/32.png) [@Animastryfe](https://boards.straightdope.com/u/Animastryfe)\ **Post date:** [June 4, 2009, 10:53pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/35 "2009-06-04T22:53:56Z")
> [@muldoonthief](#): > > Then how come they don’t make the whole plane out of the black boxes? > > ::d&r:: Cecil has answered this: > **[If aircraft "black boxes" are indestructible, why can’t the whole plane be...](https://www.straightdope.com/21342059/if-aircraft-black-boxes-are-indestructible-why-can-t-the-whole-plane-be-made-from-the-same-material)** ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [June 4, 2009, 10:55pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/36 "2009-06-04T22:55:07Z")
> [@mnemosyne](#): > > Re: airbags > > That would require more space available in the plane for the recorders and the volume of airbags, and since every cubic inch of space is maximized in a plane, that’s not likely to happen. Where did you get this idea? Airliners are full of empty space. It’s empty to save weight. Adding a small chute and a shotgun shell to eject it would add little to the weight or complexity of a box. Since we’re already using satellite uplinks it will certainly increase with the amount of data that is streamed during an emergency. When that matches the data stored on the box it will be relegated to secondary backup status. ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [June 4, 2009, 11:35pm UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/37 "2009-06-04T23:35:08Z")
> [@Magiver](#): > > Where did you get this idea? Airliners are full of empty space. It’s empty to save weight. Adding a small chute and a shotgun shell to eject it would add little to the weight or complexity of a box. > . At least in the Challenger planes, the area in which the recorders are stored really isn’t all that big (I’ve been there and seen it in 605s, 850s(200s) and 300s, in case you’re wondering). Maybe a few inches in any direction before you encounter something else, and they are in the very rear of the plane, where it tapers off. Having airbags deploy around the box while inside the plane means that the space around the shelf where the recorders are would have to be available to allow them to deploy without interfering with anything else, because the pilots will still need to be able to at least try and save the plane. Deploying airbags could hit the air conditioning systems, or significant parts of the wiring that leads to the back of the plane (control surfaces in FBW, sensors and flight computers, APU, etc). At least, that’s what I imagine from the airbag suggestion - something that expands like in a car and bubble-wraps the boxes? Also, ejecting the box with a chute would require some sort of ejection door/floor, which would require completely redesigning the hydraulic lines and wiring harnesses in the empennage, re-evaluating the structural integrity of the plane (back to research and development), getting the plane approved (non-trivial), etc. Not impossible, but unlikely to happen. Even the minimal extra weight, without considering everything else, would be a fairly long project in documentation, design and calculation (of effect on centre of gravity), validation and approval with every government agency under whose jurisdiction the plane operates (FAA, TC, EASA…). I witnessed part of a discussion involving the work required for 5lbs equally distributed on both wings. It’s insane. ---
**Author:** ![FoieGrasIsEvil](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foiegrasisevil/32/16638_2.png) [@FoieGrasIsEvil](https://boards.straightdope.com/u/FoieGrasIsEvil)\ **Post date:** [June 5, 2009, 12:12am UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/38 "2009-06-05T00:12:16Z")
> [@muldoonthief](#): > > Plus, flights where you’re most likely to not find the box, over oceans, are the ones where it’s hardest to transmit data. No receiving station in the middle of the Atlantic, so you have to broadcast to a satellite, which then has to retransmit your data down to a ground station. Which isn’t cheap, or easy, when you’re travelling at 600 kts. Yeah. If there’s no radar coverage in these areas, then the likelihood of true real time streaming data become very murky. I think they should implement both. Keep the flight recorders, because they have proven to be very useful and generally recoverable and also have some type of satellite link for oceanic flights to stream data to. You could use some other streaming system for data for overland flights. ---
**Author:** ![FoieGrasIsEvil](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foiegrasisevil/32/16638_2.png) [@FoieGrasIsEvil](https://boards.straightdope.com/u/FoieGrasIsEvil)\ **Post date:** [June 5, 2009, 12:16am UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/39 "2009-06-05T00:16:05Z")
> [@mnemosyne](#): > > This is also an industry that is relatively resistant to change, at least when it comes to mandatory technology changes, because of the massive cost in retrofitting existing aircraft. > > Planes are designed to have service lives of 20 or 30 years, and a relatively small number of new planes enter service every year. In theory, it’s the older planes that are more at risk of a crash, though I don’t really know if the data actually indicates that. Requiring that technology like this becomes installed means that the airlines/flight operators would have to spend a bunch of money, and ticket prices for passengers/cost for cargo would go up, etc. Additionally, it wouldn’t be sufficient for just the FAA to require it; the entire worldwide aviation industry would have to agree to this, and there are currently 188 members of ICAO, not all of which could afford the data centres or aircraft upgrades either. > > I don’t have any numbers to support this, but in my readings of plane crashes and their investigations, there are very, very few cases where the black boxes cannot be found on land or in water. I am not an expert by any means, but I can’t even think of a case other than this one where that happened. They are designed to withstand impact, fires, high underwater pressures, and to emit radio signals for up to 30 days when disconnected from the aircraft. They are usually found, and this particular case is incredibly unusual in that no one has been able to detect them yet (which is why they are being considered lost - overflying planes should have been able to “hear” them). Yes. How often does a plane crash over the ocean with depths of thousands of feet while at cruising altitude? Don’t most planes suffer most problems upon takeoff/landing (which would indicate the large percentage of crashes were over land, rendering the black boxes eminently recoverable)? ---
**Author:** ![Huerta88](https://avatars.discourse-cdn.com/v4/letter/h/82dd89/32.png) [@Huerta88](https://boards.straightdope.com/u/Huerta88)\ **Post date:** [June 5, 2009, 12:33am UTC](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730/40 "2009-06-05T00:33:30Z")
> [@Chessic\_Sense](#): > > Personally, I think the fact that we use them at all is only 20% to find out what went wrong and 80% to satisfy the morbid curiosity of onlookers and help give closure to families of victims. I think the current system works just fine for the minimal amount of tangible good it does us. I’d rather not spend $billions improving a system so we can learn just a tad more about what went wrong on a tiny tiny fraction of flights. I don’t share your impression. For instance, the 2001 AA JFK crash was re-constructed entirely from black box data, and is currently being taught as a very important case study in how to deal with wake turbulence and not over-compensating with rudder pedal movements. I kind of think that’s important as I don’t want my tail stabilizer coming off. The Dallas windshear crash also seems to have significantly changed procedures and training, again based in large part on the recorder data. To the post that we’ve never not found recorders before: the 9/11 recorders weren’t found, not that you’d expect to recover useful flight-safety information there. [Previous page](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730.md?page=1) [Next page](https://boards.straightdope.com/t/why-are-we-still-looking-for-black-boxes/498730.md?page=3)