Lava Flow | Images of Old Hawaiʻi

Like most Hawaiian eruptions, the eruptive activity was immediately preceded by a swarm of earthquakes, followed by tremor. Mauna Loa (“Long Mountain”) began erupting at 6:20 pm on November 21, 1935.

The eruption started with a curtain of fountains near North Pit within the summit caldera, Mokuʻāweoweo. The vents migrated 2-miles down the northeast rift zone.

During the six days of the main event, fissures opened up along the northeast rift zone of the mountain, fountaining lava 200- to 300-feet into the air.

On November 26, the summit eruption died and the northeast rift activity was reduced to a single vent at the 11,400-foot elevation. A small vent also opened up further below on the north flank of the mountain at the 8,600-foot elevation. (USGS)

Lava flows from Mauna Loa were generally fast-moving and voluminous. Lava moved relentlessly at a rate of five-miles each day; it pooled up between Mauna Kea and Mauna Loa at about where the Saddle Road is situated.

The ponded lava eventually began to follow the lay of the land, a natural drainage … Then, things “got interesting.” Lava was heading directly toward Hilo. (USGS)

Dr. Thomas A Jaggar Jr, the government volcanologist, estimated that the flow would reach Hilo by January 9, 1936. He suggested using dynamite to collapse lava tubes near the source of the flow in order to stop or divert it.

Explosives were first suggested as a means to divert lava flows threatening Hilo during the eruption of 1881. However, Jaggar’s plan of mule teams hiking the explosives up the mountain would take far too long – the lava flows were moving a mile a day.

Guido Giacometti, a friend of Jaggar, had suggested using US Army Air Corps bombers to precisely deliver explosives. Jaggar agreed, and the call was made.

The US Army Air Corps approved, and the mission and plans to strategically bomb Mauna Loa were set into motion. Lieutenant Colonel George Smith Patton was called on to oversee the Army operation. (He’s the same Patton who would go on to WWII fame.)

Lava tubes are cooled and hardened outer crusts of lava which provide insulation for the faster-flowing, molten rock inside. Such a conduit enables lava to move faster and farther.

The theory was bombs would destroy the lava tubes, robbing lava of an easy transport channel and exposing more of the lava to the air, slowing and cooling it further. (BBC)

On December 26, 1935, six Keystone B-3A bombers of the 23d Bomb Squadron and four Keystone LB-6A light bombers from the 72d Bomb Squadron joined the rendezvous circle in the predawn darkness off Diamond Head, and then headed to Hilo.

Jaggar briefed the crews on the methods he had in mind to divert the lava flow. He then flew over the volcano to assess the flows and select the right points for bombing.

8:30 am, December 27, 1935, the first five bombers departed on the bombing mission. (A second flight of five aircraft was planned for the afternoon.) Each plane carried two 300-pound practice bombs (for practice and sighting,) as well as two 600-pound Mk I demolition bombs (355 pounds of TNT each.)

The bombers opened formation and fell into a huge circle for a follow-the-leader dummy run over the target area. They were flying at about 12,500-feet, not far above the 8,600-foot altitude of the volcano’s flows.

As the lead pilot tipped the control column forward for his run he lowered the wheels, so that by the time he neared the clump of koa trees which served as reference point his plane would be moving only a little faster than the 65-mph landing speed.

‘OK?’ he called to his bombardier as they began their climb after passing over the flow. Standard radio-voice procedure was unneeded. … ‘OK,’ the bombardier grunted. (Johnson)

Five of the twenty bombs struck molten lava directly, most of the others impacted solidified lava along the flow channel margins; one of them turned out a dud.

“Colonel William C Capp, a pilot who bombed the lower target, reported direct hits on the channel, observing a sheet of red, molten rock that was thrown up to about 200′ elevation and that flying debris made small holes in his lower wing.”

“Bombs that impacted on solidified, vesicular pāhoehoe along the flow margin produced craters averaging 6.7-m diameters and 2.0-m depth….” (Swopes)

“Pilots observed that several bombs collapsed thin lava tube roofs, although in no case was sufficient roof material imploded into the tube to cause blockage.”

Jagger wrote that “the violent release of lava, of gas and of hydrostatic pressures at the source robbed the lower flow of its substance, and of its heat.”

The lava stopped flowing on January 2, 1936. The effectiveness of the lava bombing is disputed by some volcanologist. (USGS)

Here’s a link to a video of the Army bombing runs in 1935. (Lots of information here from Army, USGS, hawaii-gov, 4GFC, Johnson, Lockwood & Torgerson, Swopes and This Day in Aviation History.)

http://www.criticalpast.com/video/65675069574_bomb-Mauna-Loa_divert-lava_Keystone-B-3A_Keystone-LB-6A_United-States-fliers

Three Keystone B6As of 20th Bombardment Squadron, 2d Bomb Group, release their bombs on a practice mission

Plume from a test bombing of an old lava flow on Mauna Loa, performed in 1975

Lieutenant General Patton in 1935, prior to World War II

Keystone B-3A Bomber of the type used in the bombing of the volcano above Hilo in 1935

Dr. Thomas Jaggar and wife, Isabel Maydwell – 1917

Advancing lava flow, December 1935. (USGS)

“We could hear the explosions in Hilo; it was like the noise of battle.”

“Day and night the ancient forest was ablaze, and the scene was vivid beyond description. By the 25th of March the lava was within seven miles of Hilo, and steadily advancing. Until this time we had hoped that Hilo would not be threatened. But the stream pursued its way.” (Coan)

On November 5, 1880, an eruption located near the 11,000-foot elevation, about a mile above Puʻu Ulaʻula began on Mauna Loa’s northeast rift zone that would eventually send lava closer to Hilo Bay than any other in over a thousand years.

May 1st, 1881, a small, short-lived eruption at Mauna Loa’s summit heralded the beginning of an eruptive sequence that was to be followed six months later by the voluminous flank eruption which would soon threaten the then-small town of Hilo.

“The glare was intense, and was seen at great distances. Brilliant jets of lava were thrown high in the air, and a pillar of blazing gases mounted thousands of feet skyward, spreading out into a canopy of sanguinary light which resembled, though upon a larger scale, the so-called “pine-tree appendage” formed over Vesuvius during its eruptions by the vertical column of vapors with its great horizontal cloud.”

“Meanwhile a raging river of lava, about three-fourths of a mile wide and from fifteen to thirty feet deep, rushed down the north-east flank of the great dome, and ran some thirty miles to the base of Mauna Kea.” (Coan)

“We met crowds of people returning from the flow, and all reported it active and coming rapidly down the gulch. We rode up to it before dark and found that the stream was entirely confined to the gulch and intensely active.”

“The flow was on an average about seventy-five feet wide and from ten to thirty feet in depth as it filled the gulch up level with its banks. The sight was grand. The whole frontage was one mass of liquid lava carrying on its surface huge cakes of partially cooled lava. Soon after we arrived the flow reached a deep hole, some ten or fifteen feet in depth, with perpendicular sides.” (Hitchcock)

“Troops of boys and girls, young men and women, were watching the flow. They plunged poles into the viscid lava as it urged itself slowly onward; drawing out small lumps of the adhering fusion, they moulded it, before it had time to cool, into various forms at will.”

“They made cups, canes, vases, tubes, and other articles out of this molten clay, and these they sold to visitors and strangers at from twenty-five cents to a dollar or more for a specimen. All went away with fresh spoils from the spoiler. (Coan)

The advancing lava flow split into three forks at the 2,400-foot elevation (8.5-miles from Hilo Bay), only to reunite into a single flow at the 1,600-foot elevation (6.3 miles from the bay. The flow again split into two forks—north and south—at the 300-foot) elevation (1.6 miles from the bay.) (USGS)

The 1881 lavas reached just north of the present University of Hawaiʻi at Hilo campus. After crossing the present Komohana and Kumukoa Streets, a very narrow section crossed what is now Mohouli Street, about 300 yards above the intersection with Kapiʻolani Street.

Several hundred homes are now built on pāhoehoe lavas of the 1881 flow and can easily be recognized by their ubiquitous “rock gardens” (no soils have yet formed on this flow). Kaumana Cave was formed at this time and was a major supply conduit for the lavas that threatened Hilo. (USGS)

“The lava stream surrounded a single kalo-plant, growing on an islet of eighteen inches in diameter, and on another one twice as broad, a single banana plant. They have survived the heat and are growing finely, the only green things left in the garden”. (Coan)

The people asked Keʻelikōlani (Princess Ruth) to intercede. The Hawaiian-language newspaper Ko Hawai‘i Pae Aina published a letter with the heading “Ka Pele ai Honua ma Hilo” (Pele, devourer of land at Hilo) that describes the immediate danger, “Hapalua Mile ka Mamao mai ke Koana aku” (the distance from town being only one half mile.) (Bishop Museum)

“Without delay a council, high and solemn, was held in Honolulu by the principal natives; and Princess Ruth, or Luka, as her name was in Hawaiian, a lineal descendant of Kamehameha the Great, the conqueror of all Hawaii, was dispatched to offer compelling sacrifices to the goddess”.

“(T)his six decades after the first American missionaries had come to convert the Hawaiians to Christianity, fifty years or so after the zealous Hawaiians had carved blocks of stone from coral reefs and dragged them inland, there to erect churches that stand to this day. … (T)he princess accordingly embarked on the Iwalani at Honolulu.”

“An innumerable throng saw her embark and sail from Honolulu for Kailua. … Other boats took the retainers, pigs, pigeons, and the remainder of the paraphernalia for the rites at the burning mountain, and the second mate, Kauhane, went on shore to supervise operations there.” (Cameron, 1928)

“The flood came on until all agreed that in two or three days more it would be pouring into our beautiful bay. On the 10th of August it was but one mile from the sea, and half a mile from Hilo town.” (Coan)

Keʻelikōlani offered traditional oli (chants) and hoʻokupu (tribute) to Pele and later reportedly camped at the foot of the flow. (Bishop Museum)

“Ruth did manage to perform the rites, assisted by many kahunas; she made her burnt offerings, which Pele gladly accepted. Perhaps the goddess hungered for roast pig; maybe she was overawed by the royal descent of Ruth; more probably Pele stood in terror of the mortal.”

“Whatever the explanation, the lava flow ceased.” (Cameron, 1928)

Dynamite explosives had been suggested as a means to divert lava flows threatening Hilo. (Lockwood & Torgerson) However, before that plan could be put into execution, the lava flow stopped – August 10, 1881. (Kuykendall)

Follow Peter T Young on Facebook

Follow Peter T Young on Google+

Follow Peter T Young on LinkedIn

Follow Peter T Young on Blogger