# Why do airliner black boxes still exist? **URL:** \ **Category:** Factual Questions\ **Created:** [October 14, 2020, 3:58am UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905 "2020-10-14T03:58:14Z")\ **Posts on this page:** 14\ **Page:** 2
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 15, 2020, 1:20pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/21 "2020-10-15T13:20:07Z")
Not exactly. The water at the Deepwater Horizon location was roughly 5,000 ft deep. Relevant snip from [**wiki on Deepwater Horizon**](https://en.wikipedia.org/wiki/Deepwater_Horizon): > In February 2010, _Deepwater Horizon_ commenced drilling an exploratory well at the Macondo Prospect Mississippi Canyon about 41 miles (66 km) off the southeast coast of Louisiana, at a water depth of approximately 5,000 feet (1,500 m). The hole they bored into the earth underneath that water was deeper, although I could not readily find a cite for how deep the hole was. The 35,000 feet mentioned in various articles refers to the maximum drilling depth capability of the rig. All the stuff that was forensically relevant was on the surface of the seabed. Either installed there before the explosion (e.g. blowout preventer), or sank there after the explosion (the rest of the rig and drill string). In any case, it wasn’t hard to find at least the big pieces. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [October 15, 2020, 2:06pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/22 "2020-10-15T14:06:47Z")
> [@LSLGuy](#): > > The 35,000 feet mentioned in various articles refers to the maximum drilling depth capability of the rig. Which, it should be noted, is very close to the deepest point in the ocean (~36,000 feet). ---
**Author:** ![Kimera757](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kimera757/32/3765_2.png) [@Kimera757](https://boards.straightdope.com/u/Kimera757)\ **Post date:** [October 15, 2020, 2:30pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/23 "2020-10-15T14:30:23Z")
> [@whc.03grady](#): > > In this day and age wouldn’t it be trivially easy to gather and record flight data and cockpit chatter in real time via satellite or similar? It is always best to have a backup. It can’t hurt (especially in the super safety-oriented airline industry). Once in a while we have a mysterious crash (such as the _Malaysia Airlines_ MH370 _disappearance_) where radar tracking was insufficient to solve the mystery. In fact, afterward people demanded better black box technology, suggesting black boxes will become more important in the future! ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [October 15, 2020, 3:10pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/24 "2020-10-15T15:10:00Z")
> [@Kimera757](#): > > It is always best to have a backup. It can’t hurt Yes, it can hurt. That backup adds cost, against which the potential benefit must be weighed. People are fond of saying “if it saves just one life it will have been worth it,” but **[that’s true only if it costs less than about ten million dollars](https://en.wikipedia.org/wiki/Value_of_life#United_States)**. ---
**Author:** ![Kimera757](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kimera757/32/3765_2.png) [@Kimera757](https://boards.straightdope.com/u/Kimera757)\ **Post date:** [October 15, 2020, 3:20pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/25 "2020-10-15T15:20:44Z")
Boeing’s lack of attention to safety resulted in substantial financial losses. I suspect they lost more than the value of the lost passengers and crew, if each life is worth $10 million. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [October 15, 2020, 4:52pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/26 "2020-10-15T16:52:50Z")
I assume you’re referring to the crashes of the Lion Air and Ethiopian Airlines 737 MAX aircraft. Real-time telemetry would not have saved any of those passengers or prevented any of Boeing’s subsequent financial losses. The data collected from the FDR/CVR units on those planes absolutely will save future lives; however, real-time telemetry on those flights would not have saved any _additional_ lives above and beyond that, and so would have had zero value here. **[According to Wikipedia](https://en.wikipedia.org/wiki/List_of_unrecovered_and_unusable_flight_recorders)**, there have been 12 aviation incidents in the past two decades in which flight recorders were either not found or not usable. Of those twelve, three were associated with the 9/11 attacks; there doesn’t seem to be much mystery about what happened on board those flights, so it seems unlikely that telemetric data from those flights would have saved additional future lives beyond the measures we’ve already taken. A fourth incident involved a stolen aircraft that was never recovered; no life-saving lessons to be learned from that flight, although I suppose telemetry might have aided in finding the stolen plane. That leaves just eight loss-of-life incidents in 20 years with no black-box data. It’s not known whether info from those flights would have resulted in life-saving changes to future aviation practices. To estimate that, you’d need to look at the history of plane crashes over the past few decades to see, among other things, what percentage yielded black-box data that did result in life-saving changes to regs, and what percentage had no recoverable black-box data. ---
**Author:** ![Kimera757](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kimera757/32/3765_2.png) [@Kimera757](https://boards.straightdope.com/u/Kimera757)\ **Post date:** [October 15, 2020, 5:30pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/27 "2020-10-15T17:30:56Z")
> [@Machine\_Elf](#): > > I assume you’re referring to the crashes of the Lion Air and Ethiopian Airlines 737 MAX aircraft. Real-time telemetry would not have saved any of those passengers or prevented any of Boeing’s subsequent financial losses. The data collected from the FDR/CVR units on those planes absolutely will save future lives; however, real-time telemetry on those flights would not have saved any _additional_ lives above and beyond that, and so would have had zero value here. I was referring to the value of a human life more than the black box. If Boeing valued a human life at $10 million they still should have only sold airplanes with at least two sensors. They lost a lot of money once the scandal broke. (Airlines that bought these, without the “optional” extra sensors, are also to blame.) ---
**Author:** ![JustSaying3](https://avatars.discourse-cdn.com/v4/letter/j/df705f/32.png) [@JustSaying3](https://boards.straightdope.com/u/JustSaying3)\ **Post date:** [October 15, 2020, 5:33pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/28 "2020-10-15T17:33:03Z")
The 9-11 plane black boxes weren’t all completely unusable. The voice recordings probably had some impact on cockpit security. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [October 15, 2020, 6:11pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/29 "2020-10-15T18:11:14Z")
From my link, the FDR/CVR units on the planes that hit the WTC towers were never found. For the plane that hit the pentagon, the FDR/CVR units were recovered, but the CVR was damaged beyond utility. That leaves United 93 as the only flight with usable CVR data. Most of the detailed info about events on the 9/11 planes comes from phone calls made by passengers and cabin crew, using cell phones and seatback telephones (on AA Flight 11, the first one to crash, the cabin crew were able to discreetly reach AA operations center and explain what was happening; also, one of the highjackers in the cockpit accidentally made an announcement to ATC instead of the cabin PA system). I’m speculating at this point, but it seems highly likely that even without any data or audio from the planes, we would have figured out that all four aircraft were hijacked and deliberately crashed, and would still have mandated better cockpit security on commercial aircraft in the future. This would mean the value of the future lives saved by real-time telemetry on those planes would probably be zero. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [October 15, 2020, 6:24pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/30 "2020-10-15T18:24:30Z")
There is already space-based ADS-B surveillance on board Iridium satellites. ---
**Author:** ![robby](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robby/32/11048_2.png) [@robby](https://boards.straightdope.com/u/robby)\ **Post date:** [October 15, 2020, 9:13pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/31 "2020-10-15T21:13:43Z")
> [@DPRK](#): > > There is already space-based ADS-B surveillance on board Iridium satellites. But inspired by [this thread](https://boards.straightdope.com/t/potential-crash-in-orbit/923024) I read earlier, are there black boxes on board the Iridium satellites? 😉 > **[2009 satellite collision](https://en.wikipedia.org/wiki/2009_satellite_collision)** > > On February 10, 2009, two communications satellites—the active commercial Iridium 33 and the derelict Russian military Kosmos 2251—accidentally collided at a speed of 11.7 km/s (26,000 mph) and an altitude of 789 kilometres (490 mi) above the Taymyr Peninsula in Siberia. It was the first time a hypervelocity collision occurred between two satellites; previous incidents had involved a satellite and a piece of space debris. > Kosmos 2251 was a 950-kilogram (2,100 lb) Russian Strela military commun... ---
**Author:** ![user\_hostile](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/user_hostile/32/474_2.png) [@user\_hostile](https://boards.straightdope.com/u/user_hostile)\ **Post date:** [October 19, 2020, 9:23pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/32 "2020-10-19T21:23:29Z")
You misunderstood my intent. The idea of up-linking real-time data to a satellite doesn’t seem to justify the cost/benefit–no where did I imply that safety should be tossed aside because it “just doesn’t happen anymore” (at least in the US). This isn’t just some rhetorical response, BTW, I lost a brother in a Class A mishap involving a Coast Guard aircraft. I’ve also loss a co-worker who died in a GA crash. The former was caused by shitty maintenance by another service branch in the former and the latter was pilot error. So, yeah, I’m little prickly about aircraft safety. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 19, 2020, 11:25pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/33 "2020-10-19T23:25:12Z")
Well said. Every dollar we spend chasing silly things in the name of “safety!!1!” is a dollar diverted from pursuing things that actually improve actual safety. There is always room for legitimate debate on where the closest snake or low-hanging fruit is. Datalinking everything all the time pretty obviously ain’t it. ---
**Author:** ![drewder](https://avatars.discourse-cdn.com/v4/letter/d/57b2e6/32.png) [@drewder](https://boards.straightdope.com/u/drewder)\ **Post date:** [September 28, 2021, 12:43pm UTC](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905/34 "2021-09-28T12:43:11Z")
As a network engineer you don’t trust wireless connections for important data of any sort because the reliability just isn’t nearly as good. There are also privacy and security issues that have to be addressed. Satellite bandwidth is expensive and uplink speeds are relatively slow particularly with the number of planes flying around, especially when each plane is a moving target. Plus airplane accidents generally happen during bad weather and bad weather blocks most Satellite uplinks. A flight recorder is recording tons of data every second and offloading that data in real time in the middle of the pacific ocean is not practical or even particularly desirable. Real time access doesn’t save the lives of anyone on the plane, it only is useful to the people on the next plane, and like an autopsy speed isn’t really an issue. [Previous page](https://boards.straightdope.com/t/why-do-airliner-black-boxes-still-exist/922905.md?page=1)