# Previous volcanos and aircraft damage **URL:** \ **Category:** Factual Questions\ **Created:** [April 19, 2010, 10:56am UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620 "2010-04-19T10:56:16Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [April 19, 2010, 10:56am UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/1 "2010-04-19T10:56:16Z")
About 30 years ago, there was a largish eruption[sup]1[/sup] of ash in a location that was west (about the same distance as Eyjafjallajökull is from Europe) of a heavily populated area. The wind was going east at the time, so the heavily populated area should have had a similar ash cloud over it. As far as I remember, there was no suspension of airline flights except at those airports where a substantial amount of ash had fallen. Those were all fairly near the volcano and not in the heavily populated area. So what happened then? Were the airplanes of the time damaged, but no one associated that damage with the volcano? Or they did associate it, but just lived with it? Or there wasn’t much damage to aircraft, which may mean they are being over-cautious with the current ash cloud? Or did the ash cloud actually go around the heavily populated area? (I’m fairly sure I remember reports of detection of the ash from that area, but memory is potentially wrong here.) [sup]1[/sup] Saint Mt Helen or some such. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [April 19, 2010, 11:14am UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/2 "2010-04-19T11:14:57Z")
Just a tiny eruption of Mount St. Helens in 2004 caused flights to be canceled. > [@](#): > > KGW-TV/DT Portland reports that there were three large bursts, than the eruuption tapered off. No lava in site. Ash and steam from the eruption have caused several flights to be cancelled out of Portland and Seattle. From here: [http://mypetjawa.mu.nu/archives/048312.php](http://mypetjawa.mu.nu/archives/048312.php) As for the big eruption in 1980, according to Wikipedia several airports were closed and over a thousand flights were canceled. The U.S. is pretty large. The ash from Mount St. Helens royally screwed up air traffic in the affected areas, but as this map shows, most of the U.S. was not affected by ash, and much of the areas that were affected were not large population centers. > **[File:1980 Mount st helens ash distribution.svg](https://en.wikipedia.org/wiki/File:1980_Mount_st_helens_ash_distribution.svg)** > > Click on a date/time to view the file as it appeared at that time. > You cannot overwrite this file. The following page uses this file: > The following other wikis use this file: ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [April 19, 2010, 12:13pm UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/3 "2010-04-19T12:13:07Z")
That second map is just where ash was found on the ground. I was talking about the ash cloud. There would have been one over the Midwest (which is roughly the same distance from St Helens as central Europe is from Eyjafjallajökull) and probably even further east. Any idea how far east these flights were cancelled? ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [April 19, 2010, 12:41pm UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/4 "2010-04-19T12:41:28Z")
East, no, but I remember flights being disrupted for over a week into Anchorage. Mainly because they all originated or departed from Seattle. ---
**Author:** ![wmfellows](https://avatars.discourse-cdn.com/v4/letter/w/c2a13f/32.png) [@wmfellows](https://boards.straightdope.com/u/wmfellows)\ **Post date:** [April 19, 2010, 12:56pm UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/5 "2010-04-19T12:56:27Z")
> [@dtilque](#): > > That second map is just where ash was found on the ground. I was talking about the ash cloud. There would have been one over the Midwest (which is roughly the same distance from St Helens as central Europe is from Eyjafjallajökull) and probably even further east. Any idea how far east these flights were cancelled? Perhaps not, different weather patterns and ash type might have led to a more compact ash cloud. ---
**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\ **Post date:** [April 19, 2010, 7:30pm UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/6 "2010-04-19T19:30:08Z")
> [@dtilque](#): > > [sup]1[/sup] Saint Mt Helen or some such. The correct name is Mount St. Helens. Remember that. There will be a closed book quiz on Friday covering all aspects. 😃 ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [April 20, 2010, 8:39am UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/7 "2010-04-20T08:39:45Z")
> [@wmfellows](#): > > Perhaps not, different weather patterns and ash type might have led to a more compact ash cloud. I have vague memories of Mt St Helens ash being detected in places further east: I think on the east coast and in Europe, possibly in Asia too. This was within a few days of the erruption. In terms of distance from the volcano, they’d have had to close airports from Denver to Chicago to match what the Europeans have done. That would have resulted in far more than just 1000 flights cancelled, even if they only did it for a few days. As I recall, SeaTac airport was not actually closed by the May 18 erruption. The ash was carried strongly eastward, so Seattle didn’t get any. However, a number of flights from the east to Seattle were no doubt cancelled since they would have had to fly through the ash cloud. Seattle did get some ash from one of the secondary erruptions that followed. There was one a week after the main blast, one two weeks after (which I think is the one that went north to Seattle) and one a couple months later in July. ---
**Author:** ![Cheshire\_Human](https://avatars.discourse-cdn.com/v4/letter/c/5f8ce5/32.png) [@Cheshire\_Human](https://boards.straightdope.com/u/Cheshire_Human)\ **Post date:** [April 20, 2010, 9:21am UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/8 "2010-04-20T09:21:10Z")
> [@Duckster](#): > > The correct name is Mount St. Helens. > > Remember that. There will be a closed book quiz on Friday covering all aspects. > > 😃 Including what you can do with the ash. I fertilized a plant, and polished out a scratch in my glasses with the stuff. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [April 20, 2010, 1:07pm UTC](https://boards.straightdope.com/t/previous-volcanos-and-aircraft-damage/536620/9 "2010-04-20T13:07:35Z")
One of my pilot friends actually did have a close encounter with Mt. St. Helens ash while flying a King Air on business. He never _saw_ ash, but the engines had to be overhauled/rebuilt and all the windows in the airplane replaced. His employer was not amused, but happy he didn’t crash. So, yes, it dd affect airplanes. The Mt. St. Helens eruptions, though probably had a different composition and wind patterns may not have directed the ash cloud towards major airports or flights at the time. A quick look at Widipedia indicates that the part of the eruption that generated an ash plume was of considerably shorter duration than that of Volcano-With-Unpronounceable-Name, so disruption to air travel did not continue for as long a time… Additionally, the interior of North America is not nearly as densely populated as Europe, and thus far fewer people were affected by any such disruptions.