In October 2005 I was
lucky enough to
volunteer and visit Kahoolawe, a Hawaiian island used for bombing
practice by the US Military since 1941. The bombing has stopped and the
island is in the process of being rehabilitated. I volunteered with KIRC
- the Kahoolawe Island Reserve Comission
- to do some good "dirty" work preparing for the coming planting
season. (In addition to the bombs, goats and cattle had done serious
damage to the vegetation of the island)
Among other interesting things done to the island, in 1965, the Navy
decided to investigate the effects of a large
"conventional" explosion on their ships, twice (maybe 3
The US was no longer doing nuclear tests in the open air.
500 tons of explosive were piled up near the shore, and set off, with a
few ships parked just off shore. A second blast was set off at the same
location, leaving a nice crater. (I haven't found out if they filled in
the crater in between)
Fortunately, we had time to visit the crater in the morning, and the
low sun was able to bring out what appeared to be shattercone in the
Military images first:
Rockets were flown overhead to observe the shock effects - in addition,
aircraft were also flying overhead and recording the tests.
Do a search for Sailor Hat on YouTube, and you'll find the moving
The shock wave is easily visible.
Not only is the initial shockwave (on the water) visible - but also
compression/rarefaction waves setting off condensation clouds.
Military images not displayed - Pile
After the two tests, this is an aerial image of the crater. Date
uncertain - but much after the tests and before my visit in 2005.
From Google Earth - the appearance of the crater currently (within the
last few years)
Crater Rim size is between ~76 and ~86 meters (measured with Ruler in
Approaching the crater from the "car park"
Panoramas of Sailor Hat Crater - 500 Tons of TNT makes a nice hole in
the ground - 75-86M
Water was extracted from the crater for awhile - see the pipe above.
Piece of Basalt with melt effects
Outer rim of the crater - ejecta and melted basalt
A series of what appears to be shocked basalt / shattercones
Pictures - short description
Fuller description - similar images
Images by ted Brattstrom-2005, Google, USNavy
Page updated 15-Apr-2009