# Plane dumps fuel on Elementary school playground. **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [January 14, 2020, 10:45pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428 "2020-01-14T22:45:35Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [January 16, 2020, 10:31pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/41 "2020-01-16T22:31:43Z")
> [@CurtC](#): > > The pilots don’t have to go down that decision tree, because the company manual already did it for them. The cost of the fuel jettisoned is much less than the potential damage to the plane, even without considering safety aspects apparently. I think you are misinterpreting the manual. In the case of a “land at nearest suitable airfield” emergency, such as an engine failure, landing overweight is approved. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [January 16, 2020, 10:33pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/42 "2020-01-16T22:33:28Z")
> [@txjim](#): > > This is a red-letter day for me, my first scolding on the SDMB! 😃 > > Given the subject (and the fact that undeclared acronyms are a common occurance in this board) I assumed people were not going to think it was alternating current. In my defense, I work in the industry and frequent aviation boards. FWIW, I read to the end of your post assuming it meant air conditioning. And I was pretty puzzled as to why damage to the air conditioning was a concern. ---
**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:** [January 17, 2020, 12:14am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/43 "2020-01-17T00:14:09Z")
I don’t know anything about jet fuel but aside from skin contact, doesn’t it give off fumes that are dangerous to breathe? ---
**Author:** ![txjim](https://avatars.discourse-cdn.com/v4/letter/t/f07891/32.png) [@txjim](https://boards.straightdope.com/u/txjim)\ **Post date:** [January 17, 2020, 1:36am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/44 "2020-01-17T01:36:48Z")
> [@CurtC](#): > > The pilots don’t have to go down that decision tree, because the company manual already did it for them. The cost of the fuel jettisoned is much less than the potential damage to the plane, even without considering safety aspects apparently. I don’t believe anyone here (or any other forum I’ve read) is arguing that a fuel dump should not be executed in true emergencies. Available evidence (including currently available Air Traffic Control conversation) indicates that an over ocean fuel dump was possible. And, to be honest, I really don’t care how much an overweight landing costs Delta or if the aircraft is out of service for a week or two. I believe dumping fuel at low altitude over densely populated areas should be avoided unless lives are at stake. > [@markn\_1](#): > > FWIW, I read to the end of your post assuming it meant air conditioning. And I was pretty puzzled as to why damage to the air conditioning was a concern. If you lived in Texas, you would not dispute the level of emergency caused by a failed air conditioner! ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [January 17, 2020, 1:57am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/45 "2020-01-17T01:57:36Z")
I hope a priest had the time to bless that jet fuel and make it holy before spraying it over a heavily populated area. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [January 17, 2020, 2:40am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/46 "2020-01-17T02:40:39Z")
> [@CookingWithGas](#): > > I don’t know anything about jet fuel but aside from skin contact, doesn’t it give off fumes that are dangerous to breathe? The safety sheet for kerosene says stuff like “use with ventilation adequate to keep exposure below recommended limits”, “breathing of high vapour concentrations may cause central nervous system depression resulting in dizziness, light-headedness, headache, nausea and loss of coordination. Continuous inhalation may result in unconsciousness and death”, “causes respiratory tract irritation. Irritation may lead to chemical pneumonitis and pulmonary edema. Exposure produces central nervous system depression. Aspiration may cause respiratory swelling and pneumonitis. Aspiration may lead to pulmonary edema”, though, interestingly, I see one version has, “Expected to have a low degree of toxicity by inhalation.” At any rate, if you go and smell some, it will be pretty clear there is no way, shape, or form it be good for you, and will not make for fun bathtime, as stated above. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [January 17, 2020, 3:15am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/47 "2020-01-17T03:15:37Z")
Every incident is different. Consider a compressor stall at 35,000 ft on a twin vs one at 3,000 feet. One has all kinds of wiggle room to work things out. the other is entirely dependent on the other engine and the pilot doesn’t know if it’s a contaminated fuel issue or a host of mechanical problems that interrupt fuel flow. I’ve been in a small twin engine plane scud-running at night with an engine failure. While the PIC was changing tanks over to see if that was the problem the other engine quit. Fortunately he was able to restart the good engine but when you are low to the ground the decision factor changes to “what do I need to do that covers all the unknown variables”. Let me tell you right now that 2000 feet above the ground is a bad place to research mechanical issues. Gravity weighs heavily on your mind. Dumping fuel falls into that category at low altitudes. If you don’t know for sure what the problem is then you don’t want to take a full load of fuel with you to a possible crash landing. And before anyone asks, scud-running is flying under clouds to keep the flight VFR and usually infers a low altitude flight. ---
**Author:** ![Spiderman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spiderman/32/230_2.png) [@Spiderman](https://boards.straightdope.com/u/Spiderman)\ **Post date:** [January 17, 2020, 3:39am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/48 "2020-01-17T03:39:09Z")
> [@txjim](#): > > I don’t believe anyone here (or any other forum I’ve read) is arguing that a fuel dump should not be executed in true emergencies. Available evidence (including currently available Air Traffic Control conversation) indicates that an over ocean fuel dump was possible. And, to be honest, I really don’t care how much an overweight landing costs Delta or if the aircraft is out of service for a week or two. I believe dumping fuel at low altitude over densely populated areas should be avoided unless lives are at stake. If you see the link to the CBS story in post #11, that indicates that they started dumping fuel over the ocean, & at a higher elevation, too. If that sentence is true then the question is why did they continue to dump it over land (& near the end of the flight). Did they start it & forget to stop it? Though that would mean they were dumping fuel for about 20 mins. I have no clue what the dump rate is - **Richard Pearse** is that in the manual? Did they accidentally turn it on again? I’m sure it’ll be looked at in any ensuing investigation. ---
**Author:** ![Terminus\_Est](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terminus_est/32/3087_2.png) [@Terminus\_Est](https://boards.straightdope.com/u/Terminus_Est)\ **Post date:** [January 17, 2020, 9:00am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/49 "2020-01-17T09:00:47Z")
> [@Spiderman](#): > > If you see the link to the CBS story in post #11, that indicates that they started dumping fuel over the ocean, & at a higher elevation, too. If that sentence is true then the question is why did they continue to dump it over land (& near the end of the flight). Did they start it & forget to stop it? Though that would mean they were dumping fuel for about 20 mins. I have no clue what the dump rate is - **Richard Pearse** is that in the manual? Did they accidentally turn it on again? I’m sure it’ll be looked at in any ensuing investigation. Did you watch the ATC recording I posted? When asked directly by ATC whether they needed to dump fuel, they responded bluntly “Negative”. This was at 7900’, shortly after they reported the problem. Here is a pilot’s commentary of the same [VASAviation video](https://youtu.be/JzKny78Eylg). The pilots explicitly stated they didn’t need to dump fuel and never reported that they were dumping fuel. A followup video about [B-777 Fuel Dumping and Overweight Landing Considerations](https://youtu.be/4D2Kj0t4t9s). TL;DW - A fuel dump is generally performed at 6,000’-10,000’ to allow the fuel to properly atomize before it hits the ground. Further, B777 can land overweight, even without dumping fuel. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [January 17, 2020, 9:15am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/50 "2020-01-17T09:15:05Z")
> [@Spiderman](#): > > If you see the link to the CBS story in post #11, that indicates that they started dumping fuel over the ocean, & at a higher elevation, too. If that sentence is true then the question is why did they continue to dump it over land (& near the end of the flight). Did they start it & forget to stop it? Though that would mean they were dumping fuel for about 20 mins. I have no clue what the dump rate is - **Richard Pearse** is that in the manual? Did they accidentally turn it on again? I’m sure it’ll be looked at in any ensuing investigation. I can’t find a dump rate in my manual. PPRuNer’s suggest 2000 kg / minute as a ballpark figure. It’s possible they turned it on and forgot about it or that someone in the flight deck turned it on without telling the captain or there was some kind of miscommunication. There would likely have been four pilots up front at the time as the relief crew would normally be in the flight deck for the take off. > [@Terminus Est](#): > > Did you watch the ATC recording I posted? When asked directly by ATC whether they needed to dump fuel, they responded bluntly “Negative”. This was at 7900’, shortly after they reported the problem. They were asked if they needed to **hold** to dump fuel. Their reply in the negative could’ve meant that they don’t need to hold, it doesn’t necessarily mean they didn’t need to dump. ---
**Author:** ![Terminus\_Est](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terminus_est/32/3087_2.png) [@Terminus\_Est](https://boards.straightdope.com/u/Terminus_Est)\ **Post date:** [January 17, 2020, 11:58am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/51 "2020-01-17T11:58:20Z")
> [@Richard\_Pearse](#): > > They were asked if they needed to **hold** to dump fuel. Their reply in the negative could’ve meant that they don’t need to hold, it doesn’t necessarily mean they didn’t need to dump. True. One would think that at some point they would at least mention that they were in fact dumping fuel, especially as they’d be flying in an active flight path, not to mention, you know, over Los Angeles itself. They also said that they were “not critical” and that “we got them [the compressor stall?] terminated for now”. So why the rush to get back to LAX? ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [January 18, 2020, 1:23pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/52 "2020-01-18T13:23:10Z")
[The sue-ining begins](https://www.nbcnews.com/news/amp/ncna1118261). ---
**Author:** ![commasense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/commasense/32/3017_2.png) [@commasense](https://boards.straightdope.com/u/commasense)\ **Post date:** [January 18, 2020, 6:35pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/53 "2020-01-18T18:35:17Z")
YouTuber and 737 pilot Mentour Pilot gives [his take on the incident](https://www.youtube.com/watch?v=fyE4mHkDX88). ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [January 18, 2020, 8:13pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/54 "2020-01-18T20:13:57Z")
> [@Terminus\_Est](#): > > True. One would think that at some point they would at least mention that they were in fact dumping fuel, especially as they’d be flying in an active flight path, not to mention, you know, over Los Angeles itself. They also said that they were “not critical” and that “we got them [the compressor stall?] terminated for now”. So why the rush to get back to LAX? That’s a good question. If the plane can climb on one engine and they re-establish the other engine then that allows for a broader range of options. If they made it to 8000 feet then they could continue to climb higher for more landing options. Something that enters into the picture on a quick return to an airport is that fuel is weight and weight means it takes longer to slow the plane down. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [January 18, 2020, 11:48pm UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/55 "2020-01-18T23:48:00Z")
> [@Richard\_Pearse](#): > > . > > It’s possible they turned it on and forgot about it or that someone in the flight deck turned it on without telling the captain or there was some kind of miscommunication. There would likely have been four pilots up front at the time as the relief crew would normally be in the flight deck for the take off. > They were asked if they needed to **hold** to dump fuel. Their reply in the negative could’ve meant that they don’t need to hold, it doesn’t necessarily mean they didn’t need to dump. This is what I was wondering about. As I read the thread, it talks about “the pilot” and “they said”. Who is this “They”, and why are “they” talking to flight control? Is it a decision “they” made, or is this an emergency where individuals are taking responsibility for decisions to offload tasks from the pilot, who may, or may not have been demonstrating the dramatic narrowing of attention that people get when they are stressed? ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [January 19, 2020, 9:12am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/56 "2020-01-19T09:12:06Z")
A typical long haul flight would have up to four pilots (sometimes just three) on the flight deck for the take off and departure. Two sitting at control seats and the other two in the jump seats. One of the two at a control seat would be the captain whose job it is to make decisions with the help of the rest of them. It may or may not be the captain on the radio. An engine failure shouldn’t really be something that causes much problems for a crew. It is trained over and over in the simulator. Edit: If it is not the captain on the radio, it will be another pilot who is in direct communication with the captain. ---
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [January 28, 2020, 6:46am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/57 "2020-01-28T06:46:24Z")
> [@Machine\_Elf](#): > > I’ve seen [AC or A/C used before in place of “aircraft,”](https://acronyms.thefreedictionary.com/A%2FC) but it’s usually done only in aviation-related venues where the audience is most likely to be people familiar with that usage. Yes, exactly my point. As far as I can tell, this is _not_ an aviation-only message board, it’s general interest. Therefore I would never use ‘AC’ (or A/C) to refer to ‘aircraft’ just as I would never use ‘SOT’ to refer to a soundbite. It’s jargon. If you’re not in an industry-specific venue, don’t use it. To me it comes off as a schoolkid attempt to show that s/he is “in the know” and sits with the cool kids in the cafeteria. It is “exclusivity signalling”. You could argue that ‘AC’ is more familiar than ‘SOT’ but why would you? It’s not the point. Plenty of people would know ‘SOT’\*, too, it they were forced to look it up by some insecure, inconsiderate author. I could make a post that says only: _“Ik wil een broodje met kaas”_\*\*. 95 out of 100 Dopers would have no clue what I meant until they looked it up on Google. But that’s a shitty thing to do when your audience by-and-large speaks and reads English. I believe that’s why there’s a rule here not to post in any language but English (with appropriate exceptions). When you use abbreviations and acronyms that are generally not encountered “in the wild” you must know that you are essentially using a foreign language. Please don’t do this. - “Sound On Tape” \*\* “I want a cheese sandwich” ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [January 28, 2020, 8:23am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/58 "2020-01-28T08:23:52Z")
AC=aircraft was as obvious AF from context. (Of course, AF=“auto-focus”.) ---
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [January 28, 2020, 9:39am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/59 "2020-01-28T09:39:13Z")
> [@Darren\_Garrison](#): > > AC=aircraft was as obvious AF from context. > > (Of course, AF=“auto-focus”.) From my vantage point ‘SOT’ would be obvious AF also. But you wouldn’t have known what that means, would you? See my point? Also: no one’s gonna expect “AC” means aircraft because no one ever abbreviates ‘aircraft’! That’s why it make more sense to think it means ‘air conditioning’ or ‘alternating current’. ---
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [January 28, 2020, 10:04am UTC](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428/60 "2020-01-28T10:04:26Z")
(Too late for edit) The only times people usually abbreviate ‘aircraft’ is within the industry because they get sick of typing the word out over and over. But this isn’t an aviation board so we don’t do that. This board is about fighting ignorance. I don’t see using jargon being conducive to that aim. Shibboleths are about identifying outsiders and enemies and keeping them out. That’s not what we do here. Write to inform, not to confuse. Simple when you think about it, really. [Previous page](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428.md?page=2) [Next page](https://boards.straightdope.com/t/plane-dumps-fuel-on-elementary-school-playground/846428.md?page=4)