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View Full Version : Bomb blast effects at a distance (Is this feasible?)



Tog
2014-May-20, 07:01 AM
This afternoon I was sitting in my house when everything shook. We have a large window made of a single pane of glass about 4 by 5 feet that rattled in the frame. People reported hearing and feeling it from the north end of Ogden, Utah, to Layton. The news is now reporting that it was live ordinance being dropped in the West Desert. The bomb range out there is about 50 miles from the areas that reported physical effects. There are no real terrain features to speak of, since the area between is mostly covered by the lake.

A few years ago, We lived in a different spot, about five miles from Hill Air Force Base when they had a bomb incident that involved blowing up a pair of 500 pound bombs that fell off a plane on take off. That blast was bigger then the one today, but it was also 10 times closer.

I'm just not sure I'm buying the ordinance testing story. if it shook our house at 50 miles, I bet the cars on the freeway 20-25 miles south of the range really felt it.

Are my expectations wrong? Could it really have been a bomb blast that rattled our windows from 50 miles out? There was another smaller one a few hours before.

EDIT: I see the local paper is saying it could have been F-22s doing supersonic flight maneuvers, and that there F-22s and F-16's flying over the area around the time the reports came in.

John Mendenhall
2014-May-20, 11:15 AM
like the sonic boom explanation better. also check out the recent discussions on CQ re meteor explosions.

Kaptain K
2014-May-20, 04:44 PM
It could be the sonic equivalent of a "mirage", where the differences in air densities cause the sound to bend back down. The presence of a lake lends credence in my mind.

starcanuck64
2014-May-20, 06:37 PM
EDIT: I see the local paper is saying it could have been F-22s doing supersonic flight maneuvers, and that there F-22s and F-16's flying over the area around the time the reports came in.

I lived under an Air Force training area in Northern Washington State in the early 1990s, I sometimes got hit by sonic booms that rattled the entire house. The F-15 pilots weren't supposed to go super-sonic while pointing downwards but in their enthusiasm they sometimes did and this produced the most powerful shockwaves.

redshifter
2014-May-20, 06:40 PM
I lived under an Air Force training area in Northern Washington State in the early 1990s, I sometimes got hit by sonic booms that rattled the entire house. The F-15 pilots weren't supposed to go super-sonic while pointing downwards but in their enthusiasm they sometimes did and this produced the most powerful shockwaves.


I grew up in south central Washington State in the 1970's, and we heard/felt sonic booms on quite a few occasions. That was the first thing I thought of when I read the OP of this thread.

starcanuck64
2014-May-20, 07:40 PM
I grew up in south central Washington State in the 1970's, and we heard/felt sonic booms on quite a few occasions. That was the first thing I thought of when I read the OP of this thread.

There were also the B-52s out of Fairchild. I was sitting at my computer one afternoon and felt more than heard something. I ran out the front door just as a B-52 did a low level pass directly above me, a plane with a 200 ft. wingspan looks immense even at a couple of hundred feet altitude.

Van Rijn
2014-May-20, 09:01 PM
When I was pretty young, there was an accident at a trainyard about 20 miles away with a train carrying bombs for the Vietnam War. There were a series of explosions from 250 pound bombs. I remember loud noises and the windows rattling pretty hard, but I don't recall any shaking.

wd40
2014-May-20, 10:53 PM
Is it correct that sonic aircraft booms cause window glass to rattle, but ordnance explosion booms do not?

Jens
2014-May-20, 11:34 PM
Is it correct that sonic aircraft booms cause window glass to rattle, but ordnance explosion booms do not?

Huh? Wherever did you get that idea? Of course bombs can rattle windows and when dropped directly on the house they can cause lots of other interesting phenomena as well.

wd40
2014-May-21, 12:10 AM
It may be an urban myth, but I believe that in countries where unknown booms occur frequently, they can tell from whether the glass rattles or not whether it is an aircraft passing the sound a barrier or a distant explosion, and it may be to do with Response of laminated composite flat panels to sonic boom and explosive blast loadings (http://arc.aiaa.org/doi/abs/10.2514/3.10395?journalCode=aiaaj)

Gillianren
2014-May-21, 01:15 AM
We are not terribly far from a military base in Olympia. Yes, sometimes our windows rattle from ordnance.

Ara Pacis
2014-May-21, 04:05 AM
Luckily we don't get any bombs going off around here, unless you count my neighbor playing with dynamite. We did have a long rumble the other night that sounded like one or two Blackhawks flying nearby, though we don't have an base around here. It was too deep to be medevac, and it reminded me of two summers ago when a Blackhawk at the nearby airshow flew by doing a river-run below treetop level.

Van Rijn
2014-May-21, 10:54 AM
Is it correct that sonic aircraft booms cause window glass to rattle, but ordnance explosion booms do not?

Incorrect. Look at the post directly above yours.

For closer homes, windows were shattered, and the entire building shook. I believe some homes were destroyed.

Tog
2014-May-21, 11:28 AM
I've felt a three other explosions in three other houses.

-One was a big natural gas explosion about a mile away. It was more of a "FOOM" type of feel. That is, soft on the edges and drawn out a bit.
-The second was a pair of 500 pound bombs five or so miles away, with smaller explosions going off before the second one in 30 minute intervals. Those were all more of a "CRACK." A sharp, start and stop with no real middle. In a way they reminded me a lot of the thunder from a very near lightning strike. The one's where you see the flash and make it to the "n" sound in one before the boom.
-The third one was at this same house and was an propane storage tank shuffling off this mortal coil spectacularly. This was about a mile to a mile and half away, and it shook the whole house. It was more of a CROOM. A sharp hit, then a short middle and soft end.

This is why the sonic boom makes more sense to me. When the bomb went off, I knew it was a bomb. I don't know how I knew, but I would have needed a lot of convincing to believe anything else. This thing the other day didn't strike me as a bomb right off. That cold have been the distance, and if the sonic mirage thing is true, I imagine it could have stretched out the sound a bit. A sonic boom also would have had the benefit of altitude, possibly enough to have been line of sight to the plane. If it hadn't been heard over such a wide area, I might have thought it was another (smaller) propane tank.

Trebuchet
2014-May-21, 02:40 PM
My wife heard the eruption of Mt. St. Helens from Wenatchee, WA, about 120 miles away. (I was in the shower.) Others heard it from greater distances. Some folks close up heard nothing. Sound propagation can do funny things.