TOLtommy From United States of America, joined Dec 2003, 3011 posts, RR: 5 Posted (1 year 9 months 4 weeks 18 hours ago) and read 6116 times:
There was a volcano "expert" on WWJ radio in DTW this morning. He said that the volcanic eruption in Iceland was similar to Mt. St. Helens in 1980, rather than that of Mt. Pinatubo.
It got me to wondering, was there as much closed airspace when St. Helens erupted? I remember seeing photos of Portland covered in ash, but don't recall how long any airports were shut down. And were they shut down in as wide an area as we have right now?
Arniepie From Belgium, joined Aug 2005, 1254 posts, RR: 1 Reply 1, posted (1 year 9 months 4 weeks 17 hours ago) and read 5995 times:
IIRC ,the Mt St Helens eruption was a short time event whereby the mountain pretty much tore itself apart in one huge bang after which the mountain quickly became quiet again.
Therefore it had a big short time effect (damage in the surrounding area etc. ...) but limited longtime effect on the airways.
It also did a short time eruption again in 2005 but that only lasted an hour or so (with a big 5 mile high cloud nonetheless).
Also the wind direction might have played in its favor, I don't really know but I can imagine it to be an important factor.
The Icelandic volcano erupting now is notorious for having very long duration eruptions ,the last one happened in the 1820's going on and off for about 2 years.
rfields5421 From United States of America, joined Jul 2007, 4715 posts, RR: 21 Reply 2, posted (1 year 9 months 4 weeks 17 hours ago) and read 5990 times:
This is all memory so could be faulty. It is impossible to search for this information on the web today.
Mt St Helens closed most of the air traffic across the US north of a line from SFO-DEN-RDU - I don't remember how far north it went. Traffic across the North Atlantic had to move to southern routes. There were air traffic disruptions in Europe.
Mt St Helens was a much, much more severe event initially with the initial volume of ash a huge amount.
However, my faulty memory is that Mt St Helens was a single or a relatively short term event.
The problem today is that the volcano keeps putting new ash into the air every hour. The weather and winds have long dissipated the initial ash cloud to levels not dangerous to flying. But new ash keep coming across Europe every couple hours.
TOLtommy From United States of America, joined Dec 2003, 3011 posts, RR: 5 Reply 3, posted (1 year 9 months 4 weeks 17 hours ago) and read 5969 times:
Quoting rfields5421 (Reply 2): Mt St Helens closed most of the air traffic across the US north of a line from SFO-DEN-RDU - I don't remember how far north it went.
That's what I was looking for, thanks!
Quoting rfields5421 (Reply 2):
The problem today is that the volcano keeps putting new ash into the air every hour.
Yeah, now that I remember, St. Helens was a pretty massive explosion. After she got it out of her system, she settled down again....
falstaff From United States of America, joined Jun 2006, 5087 posts, RR: 33 Reply 4, posted (1 year 9 months 4 weeks 17 hours ago) and read 5908 times:
Quoting TOLtommy (Reply 3): St. Helens was a pretty massive explosion
rfields5421 From United States of America, joined Jul 2007, 4715 posts, RR: 21 Reply 5, posted (1 year 9 months 4 weeks 17 hours ago) and read 5861 times:
If this volcano sent out as much ash as Mt St Helens, they would be using snow shovels to try and clear it from LHR and AMS.
They would need to clean the runways before they could be used at CDG and FRA.
But the Mt St Helens was one huge event with about 9-10 hours of major ash production. The ash cloud moved at about 60 mph/ 100 kph across the northern US, southern Canada and out into the Atlantic and over Europe. But the ash concentrations were thinned significantly due to the wide dispersal area. Also the Mt St Helens ash appears to have been heavier than that from this volcano, so the Mt St Helens ash fell faster.
SEPilot From United States of America, joined Dec 2006, 5853 posts, RR: 39 Reply 6, posted (1 year 9 months 4 weeks 17 hours ago) and read 5806 times:
Another big difference is that Mt. St. Helens did not have any glaciers involved. As I understand it, the fact that the Iceland volcano is erupting under glaciers causes much more of the magma to turn to ash (and may change the consistency of the ash) than would otherwise be the case. Perhaps when the glacier has completely melted in the vicinity of the eruption it will reduce the ash output.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
timf From United States of America, joined Mar 2003, 845 posts, RR: 0 Reply 7, posted (1 year 9 months 4 weeks 17 hours ago) and read 5735 times:
Were the dangers that ash posed to aircraft even known in 1980? The stories I've read about BAW009 seem to indicate it was the first reported incident of volcanic ash having such a dangerous impact on an aircraft. Since this didn't happen until 1982, it's possible that the Mt. St. Helens eruption didn't impact air travel except in the immediate vicinity of the eruption.
nwaesc From United States of America, joined Aug 2007, 3077 posts, RR: 8 Reply 8, posted (1 year 9 months 4 weeks 15 hours ago) and read 5505 times:
Quoting SEPilot (Reply 6): Another big difference is that Mt. St. Helens did not have any glaciers involved.
This is incorrect. Glacial activity (or rather, the melting of them in the blast) added to the huge mudflows that roared down through the elevations below. While perhaps not directly affecting air traffic, these absolutely choked the Columbia river, and ground maritime traffic to a halt.
"Nothing ever happens here, " I said. "I just wait."
rfields5421 From United States of America, joined Jul 2007, 4715 posts, RR: 21 Reply 9, posted (1 year 9 months 4 weeks 14 hours ago) and read 5384 times:
Quoting timf (Reply 7): Were the dangers that ash posed to aircraft even known in 1980?
Dangers were known. There were alerts and airport and airspace closures long before 1980. In 1973 or 74 when I was stationed at NAS Agana, Guam and Saipan were closed for a couple days due to ash from Mayon Volcano - 1,500 miles away in the Philippines. We did have visible ash in the air, sulphur small and ash falling on the ground.
I remember a story about a DC-3 and a four engined prop being forced down/ crash when volcano ash clogged their carbs near a Philippine volcano back in the 50s.
It is really hard to find good information on the history of aircraft and volcanos - especially with this event hogging all the search bandwidth.
Airspace around volcanos used to be closed frequently, but there was no long range monitoring or tracking as we have the capability now. There was also no where near the information flow then that we have now. People on the other side of the world did not learn about airspace and airport closures.
People were smart enough to know that aircraft engines could be damaged, windscreens destroyed and aircraft crash from volcanic ash. But it appears that mostly the procedure was to avoid flying into visible ash clouds.
The problem with the BA aircraft was two fold. It was night so the ash cloud was not visible. Secondly the thinking was that the volcano could not send a dangerous ash cloud to 36,000 ft.
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