Eruption | Images of Old Hawaiʻi

September 26, 2024 by Peter T Young Leave a Comment

1919 Alika Eruption

“Alika was a man and Hina was his wahine, and their occupation was farming. Before they would begin farming, they would vow that should their crops mature, they would consume it along with Pele, the god. But when the crops reached maturity, the two of them didn’t carry out their promise, and the day that they ate of their crops, that was when they soon died.”

“This is how it happened: Hina urged Alika to eat sweet potato, and so Alika went to dig up some, and after finding some, he baked it in the umu¹ until done and then they ate it all; then the forest began to speak as if it were a man, echoing all about them.”

“During which time, the man soon thought of their vow. Alika said to Hina, “We will die because of you,” and before he was done speaking, lava soon flamed forth and they perished.”

“And it is for this man that this land is called by that name until this day; if you look at the aftermath of the lava, in this area, the burnt homes of Kaupo stand jagged because of the spreading flames²; the land is horrid in appearance in every way; but the kamaaina love it here, and it is only the malihini who disparage it.” (Zalika, South Kona, Kuokoa, 8/7/1886)

“The greatest volcanic event in Hawaii for the year 1919 was the activity of Mauna Loa itself. It was no surprise to the unsleeping keeper of Kilauea and the Long Mountain.”

“That autumn, with its unruly flock of seismic disturbances, was a busy one for Professor Jaggar, who made more than one lofty ascent to the flaming pastures of his charge.”

“Back at Kilauea observatory, [Jaggar] noticed the fume and glow from Mauna Loa’s 13,675-foot crater, Mokuaweoweo, spreading to the southward along a route he knew well.”

“By telephone he warned Kapapala and the other districts in the course the flow would take. Many is the account I have listened to from residents of those sections who saw destruction looming far above, and who hurried to pack their belongings in preparation for flight.” (Charmian London)

On September 26, 1919, a vent high on Mauna Loa’s Southwest Rift Zone erupted for just a few hours. Three days later, a breakout lower on the rift zone erupted fountains of lava up to 400 ft high and sent a river of lava down the volcano’s forested slopes.

Within about 20 hours, an ‘a‘ā flow several hundred meters (yards) wide crossed the circle-island “Government Road” (predecessor of Highway 11), burying the small village of ‘Ālika (north of Miloli‘i). This flow can be seen today at Highway 11, mile markers 90–91. (USGS)

“Some thought they would go grey in a night, through the freaks played by the fluid avalanche, which would seem to skirmish in avoidance of an obviously doomed home. And I noticed a hesitance among these, as well as other island visitors who rushed to the ten-days’ wonder, about telling what they had seen.” (Charmian London)

“‘It’s like this,’ they faltered. ‘We saw things that nobody would believe. How do we know? We tried it out when we got home. The thing was too big, too terrible, to impress those who had not seen it – in spite of the great smoke and glare that hid Hawaii from the other islands for days and days.”

“Why, I stood on the hot bank of that burning cascade, and saw bowlders as big as houses, I tell you, perfectly incandescent, go rolling down to the sea; and-but there I go. I don’t think you’d believe the things I could tell you.’” (Charmian London)

“The lava is creeping very slowly, but it is wiping out the koa forests and the ohia in its path; and the fine grazing lands are being covered, and the ranch land where the animals of a Portuguese man of Keei are kept, and whose name is John Deniz, is half covered over by blazing lava; the land owned by Mrs. Carrie Robinson of Honolulu also is land greatly covered by blazing lava.”

“In the estimation of Tom White and those who went up with him, the branch flowing to the sea of Opihali is almost 13 miles from the government road, and the branch flowing to the sea of Kaapuna is about eight miles from the government road, and the branch flowing to the sea of Papa of Honomalino perhaps has not at all reached the area called Puu Keokeo.”

“Because of the branching of the lava flow into three branches is one of the reasons for the great weakening of the flow, even if the flow from the caldera from the mountain side is very powerful.” (Hoku o Hawaii, 10/23/1919)

When the flow reached the ocean, “Noises were heard underwater of seething and of tapping concussions. The uprush of steam where the lava made contact with the sea carried up rock fragments and sand and built a black sand cone.”

“The lava ‘rafts’ or blocks of bench magma which rolled down the live channel, were seen to bob up, make surface steam, and float out some distance from the shore without sinking at first, as though buoyed by the hot gas inflating them. Lightnings were seen in the steam column.”

“There was much muddying of the water and fish were killed in considerable number…. For 50 or more feet out to sea from the base of the great column of vapor which was rising opposite the lava channel somewhere beyond …”

“… the water was dotted with small jets and sometimes a swirling “steam spout” or tornado effect, a foot or two in diameter, would rise from the water a few feet away from the main steam column and join the cloud above.”

“Sometimes a shower of small rock fragments each two or three inches in diameter would be jetted up from a place in the water close to shore, each projectile followed by a tail of vapor, to heights 15 or 20 feet above the sea.” (Jaggar, Moore & Ault))

“… the high fountains of lava, the great detonations of explosions, the lake of fire on the mountain, and the final plunge of the melt over old lava bluffs into the sea in a river speeding five to ten miles an hour. This red torrent coursed for ten days.”

“The heat of the stilled lava was not yet gone when, four months afterward, I motored upon it where it had crossed, a hundred yards wide, the highway in Alika district – a waste of aa as upstanding as the wavelet of a tide-rip, kupikipikio.”

“It had swept everything in its path, causing suffering, fear and death among the herds.”

“A temporary restoration of the highway was begun as soon as the heat had sufficiently cooled; but it made one nervous, in an inflammable vehicle, to see how a light shower caused the lava to steam, and to feel warmth still rising from crevices. ….”

“During the eruption there was a succession of short-period, shallow tidal waves ranging from three to fourteen feet in height. These kept in trepidation the passengers on vessels of all classes that swarmed off shore.”

“An authentic tale is told of the wife of an islander being swept some distance off-shore by a subsiding tidal wave. Fortunately she was a swimmer.” (Charmian London)

The 1919 ‘Ālika lava flow advanced 11 mi in about 24 hours, reaching the sea north of Ho‘ōpūloa, where it poured into the ocean for 10 days. The eruption then slowly waned until November 5, when all activity ceased. (USGS)

July 18, 2024 by Peter T Young Leave a Comment

Waiwelawela

Paʻu o keahi o Waiwelawela o ka lua e
Aloha na poʻe la o

The pit of Waiwelawela is encircled by fire
Greetings to the people of the upland pit

(From the chant “A popoʻi haki kaikoʻo” – it describes how Pele got established in Puna; it compares the movement of the lava to the movement of water.)

There are indications that the ancient Hawaiians made use of natural hot springs for recreation and therapy. Oral history relates that the ancient chieftain, Kumukahi, frequented hot springs in Puna to relieve his aches and pains. (Woodruff/Takahashi)

“The fame of the waters of the warm springs of the Puna districts has been great during many years. In fact, it is a legend … that when the ailments of the body overcame the aliʻi of old they betook themselves to the spring known as Waiwelawela … and there they were healed of rheumatic affections through bathing, and their systemic ills cured by drinking of the waters.”

“This legend has come down to the Hawaiians of today and even now there is a fame attached to the waters of the springs, which draws to the side of the stream scores of the native residents of nearby districts.” (Pacific Commercial Advertiser, January 28, 1902)

Waiwelawela “is a warm spring, crescent shaped, and of a vivid ultramarine in color …. The spring, named the Blue Lake, is 90-deg in temperature and 900-feet above the level of the sea. The water is wonderfully clear and, strange to relate, at this elevation, it has a regular rise and fall which is said to correspond to the tide of the ocean.” (Daily Bulletin, August 28, 1882)

The Kapoho Warm Springs was formed when the downthrown block of the Kapoho fault slipped below the water table and exposed the warm waters, probably heated by a magmatic body intruded in 1840. (USGS)

“At present no practical use is made of them, but were there a proper access a small hotel would be built and many invalids would be able to make use of these springs.” (Hawaiian Gazette, September 17, 1889)

“The famous warm spring is to be found near the residence of Mr RA Lyman (Kapoho’s largest landowner) and is one of the finest bathing places on the islands. Natives formerly flocked to the place from all over the islands believing that it was possessed of great healing powers.”

“The water is a pleasant temperature for bathing and is clear as crystal, small objects can be readily distinguished twenty feet below the surface. There is a mineral taste to the water.” (Pacific Commercial Advertiser, March 22, 1892)

“The railway now goes so close to them that it is believed if a few cottages were built, and attendance provided, many afflicted people would be glad to go there and be healed. Even those who need no physician would find at these springs a place for rest and contemplation, far from the maddening crowd.” (Pacific Commercial Advertiser, October 12, 1908)

“It is the most marvelously beautiful place in all these beautiful islands. There is not a doubt of it. The pool, at the base of a small peak that is like what Diamond Head would be if that had sugar cane growing to its very summit, lies shaded by a dense growth of ʻōhiʻa and koa and lehua trees and guava bushes, the sun glistening upon it through the leaves of these.”

“The waters, not steaming, but of perceptibly higher temperature than the air, by some strange law of refraction are shot through with dazzling gleams of a blue that is like the blue depths of the sky. Yet the rocks in the pool are not blue. They are of rather reddish cast.” (Mid-Pacific Magazine, 1912)

“The exposed basin where the spring comes to the surface is something like five by six yards, and the water rises from no one knows where and departs no one sees how. The water is warm and is very full of mineral salts.” (Pacific Commercial Advertiser, January 28, 1902)

“This spot is unquestionably one of the loveliest in all Hawaiʻi, and its charm is typical of Hawaiʻi. It is close against the face of a volcanic cliff. Here there is a shady grotto, and in this grotto a pool almost as it hewed out of the rocks for the bathing place of some giant of the forest.”

“The water is in spots 20-feet deep, but so translucent that it seems much less than 10. It holds many lights and shadows, many hues and colors, varying from the deep indigo blue to a transparent jade-green and in spots a golden brown. There are seats here and the shade is grateful.” (Honolulu Star-bulletin, September 6, 1916)

At Warm Springs, where portions of ‘Bird of Paradise’ (1951) and other motion pictures had been filmed, stone steps led to a spring-fed, naturally heated pool fringed by ferns, cattleya orchids and lau hala trees.

The grounds and a half-mile drive were landscaped with plumeria, thousands of ti plants, crotons and ginger. Picnic tables and barbecue pits dotted a smooth lawn shaded by mango trees. Slim Holt, who leased the property from Lyman, had labored for years to create this beauty, assisted by interested individuals and organizations. (Flanders)

Then, “Something was amiss.” An eruption at Kilauea had ended on December 21, 1959.

“(B)ut the shallow reservoir beneath the summit of Kilauea volcano was gorged with magma, far more than before the eruption started. Rather than removing pressure, the eruption had, for all intents and purposes, created more.”

“The uncertainty ended at 1935 January 13, (1960,) when red glow in the night sky above Kapoho announced the 1960 eruption.” (USGS)

Bulldozers erected a quarter-mile line of dikes designed to prevent the lava from reaching Warm Springs. Despite this effort, toward midnight the flow surmounted the embankments.

Barbecue pits exploded; trees, shrubbery, tables and benches burst into flame. Lava poured down stone steps in a cherry-red stream. Still water, reflecting the infernal scene, disappeared under the flow. The new cinder cone was dubbed Puʻu Laimanu. … Today, buried beneath this primeval landscape, under 50-feet of lava, lays Warm Springs. (Flanders)

“Estimates of damage from the six-day eruption of Kilauea volcano rose into the millions today. State Senator Richard F Lyman estimated damage to his land, blanketed by the lava as $2,000,000.”

“He owns 80-acres of sugar land and the Warm Springs resort area, now buried by the flow on Hawaiʻi Island. Other landowners reported 3,500-acres of farmland destroyed.” (The Spokesman, January 20, 1960)

“Waiwelawela (meaning ‘warm water’) was a warm spring pool near Kapoho which was covered in the 1960 eruption. … It is said by people of the area that Pele covered the springs because people were charging others, namely Hawaiians, for use of the warm springs. In former days these warm springs were available to everyone.” (Pukui; DOE)

November 14, 2023 by Peter T Young Leave a Comment

Kilauea Iki Eruption – 1959

Volcanologists knew something was coming.

Between November 1957 and February 1959 measurements from newly installed sensitive tiltmeter bases around the summit indicated that the whole caldera region was tilting outward, apparently because magma was welling up from the mantle and accumulating in the reservoir several miles beneath the caldera.

Between August 14 and 19, 1959, a swarm of deep earthquakes was recorded on the seismographs at the Hawaiian Volcano Observatory. The earthquakes were located about 35-miles below the volcano.

By October, tilt surveys of the caldera, using the new water-tube tiltmeter network, indicated that the summit reservoir of Kīlauea was beginning to inflate with new magma. Scientists later concluded that magma began its upward journey during the August swarm.

Another series of earthquakes – shallow tiny events beneath the caldera – began in mid-September near Halema‘uma‘u Crater. By November 1, more than 1,000 tiny earthquakes were being recorded per day.

Scientists conducted another caldera tilt survey during the second week of November and discovered it was swelling at least three times faster than during the previous months. Magma was moving into the summit reservoir at a high rate.

During the afternoon of November 14, earthquakes beneath the caldera suddenly increased about tenfold in both number and intensity. For five hours, the entire Kīlauea summit region shook as seismic tremor signaled magma was forcing its way from the summit reservoir toward the surface.

An erupting fissure of small lava fountains broke through the south wall of Kīlauea Iki Crater at 8:08 p.m. In the first 24 hours, activity decreased and then eventually ceased at the outermost fissure vents. By nightfall on November 15, only a single vent on the west side of the fissure remained active.

Over the next five days, lava fountain heights fluctuated between about 650 and 980-feet, with a maximum fountain height of 1,247-feet.

A brand new cinder cone called Puʻupuaʻi (translates to “gushing hill”) was formed. As cinder and spatter rapidly accumulated to form Puʻupua‘i, slabs of congealed spatter occasionally broke loose and slid down the cone into the churning lava lake.

The 1959 summit eruption occurred in Kilauea Iki, a collapse crater adjacent to the main summit caldera of Kilauea. There were 17 eruptive ‘episodes’ (or phase) of the eruption which ranged in duration from 1 week to 1¾-hours..

On December 17, episode 15 produced lava fountains that were approximately 1,900-feet high, the highest recorded in Hawaii during the 20th century.

That’s about three times the size of the Washington Monument. That’s also 124 feet higher than the tallest building in the US now: One World Trade Center. (CNN)

Downwind from high lava fountains, forests suffered tremendous damage. Trees were stripped of leaves and branches – or completely buried – by falling cinder. You can now walk through this area of the National Park; it’s called ‘Devastation Trail.’

A few ōhi‘a trees, dead and bleached, poke up through the pumice and very gradually some ōhi‘a, ōhelo and ferns are beginning to recolonize the dead zone (unfortunately, some blackberry, too.)

Here is a video of the eruption (unfortunately, there is no sound, the sound of an eruption is as impressive as the visual):

The lava lake attained its greatest depth (414 feet) and volume (58 million cubic yards) at the end of the eighth phase on December 11, 1959. The eruption ended December 20, 1959.

When we were kids, living on Kāne‘ohe Bay on O‘ahu, whenever the eruption happened we’d go to the Big Island to see it, including the 1959 eruption of Kīlauea Iki.

April 16, 2023 by Peter T Young Leave a Comment

St Peter’s Chapel

“There are a few, very small fishing villages, Alae, Alika and Papa, which are reached by poor trails from the mauka road. It is necessary to travel from Hookena mauka to the main road to Papa, and thence by either road or trail to Hoopuloa, the last steamship landing in Kona.”

“This is another village which is dwindling in population, only a few Hawaiians and a couple of Chinese storekeepers remaining. A fair road leads across a barren a-a flow to Miloli‘i, the largest and best specimen of an exclusively Hawaiian village on the Island, which is seldom visited.”

“It is splendidly situated by a sand beach, the sea coming right up to the yard wall, and is inhabited by a rather large population of Hawaiians, who prosper through the fishing which is almost phenomenally good…”

“This region is seldom visited. Its chief points of interest are the remains of a heiau, mauka of the Catholic church at Milolii, some fine papa konane at the south end of the same village a well preserved kuula (still used) where fishermen offer offerings of fruit to insure a good catch, by the beach south of Milolii, where the Honomalino Ranch fence crosses the trail; while all along the trail are smaller kuulas, and at many points the foundations of villages, where old implements may still be found.” (Kinney, 1913)

“Hoopuloa was one of the few typically Hawaiian villages remaining in Hawaii. It comprised of a cluster of 10 to 15 homes of old Hawaiian style and boasted a population of approximately 100 persons … The wharf was a port of call for the Inter-Island steamers”. (Honolulu Star Bulletin, April 19, 1926)

Then … “The number of earthquakes recorded for April [1926] was 671 (compared with monthly average of 52 for the preceding 3 months. … The maximum daily frequency of earthquakes in the 1926 eruption was on April 15 (86 shock), the first day of free-flowing flank eruption …” (Jaggar)

Edward G Wingate, USGS topographical engineer, was mapping the summit of Mauna Loa in 1926, changing campsites as the work progressed. On April 10 his camp was along the 11,400-foot elevation, well into the desolate upland above the Kau District.

An earthquake wakened the campers about 0145; as they drifted back to sleep, a further series of quakes had them sitting up, talking, and wondering. About 0330 Wingate braved the cold and wind; with a blanket wrapped around him, he went outside and stood bathed in reddish light. (USGS)

There was a brief summit eruption, followed by 14 days of eruption on the southwest rift zone. “About 3 am April 10 (1926,) glowing lava spouted along the upper 3 miles of cones and pits of the Mauna Loa rift belt, immediately south of Mokuʻāweoweo, the summit crater. … The actual beginning shown at Kilauea by seismographic tremor was 1:36 am, followed by two pronounced earthquakes.” (Jaggar)

For three days the HVO party surveyed the sources of the eruption; then they descended and moved into Kona District, where roads, houses, and other property were threatened by the flows. Wingate and his crew stayed behind. Much of the area already mapped was under fresh lava, and there was a lot of remapping to do. (USGS)

“A crack only 1 to 3 feet wide opened southward from a point tangent to the ease edge of the bottom of the south pit of Mokuʻāweoweo, vomited out pumiceous silvery pāhoehoe froth lava, and extended itself S.30^oW. past the next two pits and over the brow of the mountain down to an elevation of 12,400 feet.” (Jaggar)

“Fortunately the main gushing of this first phase ceased about 5 am the same forenoon, after flowing 5 hours. … (Then,) The vent crack was splitting itself open downhill. The source pāhoehoe changed itself by stirring into scoriaceous aa half a mile from the vents”. (Jaggar)

“When it got close to the upland of Hoʻopuloa, the flow of lava separated into two, and one of the flows went straight for the village of Hoʻopuloa and the harbor, and the second flow went towards the village of Miloliʻi.” (Hoku o Hawaii, April 20, 1926)

“(T)he Honomalino flow to the west finally dominated, … This was also aa. … It crossed the belt road at 12:22 pm April 16, 3 miles above Hoʻopuloa village.” (Jaggar)

On April 16, Jaggar scratched marks about a foot apart across the rutted, gravel road (the only road) between the Kona and Kau Districts. A lava flow was approaching, and Jaggar wanted to measure the flow’s speed as it crossed the road.

St Peter’s Chapel, sometimes referred to as Ho‘opuloa Catholic Church, was on the makai side of the road. Perhaps a hundred people were waiting around the Hoʻopuloa Church, on the uphill side of the road, and at the Kana‘ana house opposite, on the downhill side of the road.

They had seen and heard the flow, 15-20 feet high and more than 500 feet wide, as it moved through the forest uphill. When it neared the road, people who lived on the Kona side of the flow moved off to the north, and those who lived on the Ka‘u side moved to the south, so they could go home after the road was closed. (USGS)

Jaggar recorded that it reached the uphill, inland side of the road at 12:22 at an estimated speed of about 7 feet/minute; within two minutes the road was crossed. Jaggar and his assistant, HS Palmer, stayed on the Ka‘u side. (USGS) St Peter’s Chapel, sometimes referred to as Ho‘opuloa Catholic Church, was on the makai side of the road.

“The Catholic church, where many Hawaiians worshipped, was one of the first building to be destroyed in the flow which buried Hoopuloa.” (The Star, NZ, May 21, 1926)

“It is true that I saw the church destroyed by the lava tide, which moved onward with irrevocable majesty, entering the house of worship by way of the open front door.”

“Through the windows I observed the red mass proceed to the alter as the whole structure, capable of seating 20 worshipers, burst into flames.”

“Most dramatic of all was the moment when the slow moving red-hot deluge, pressed on by the mass of lava from the rear, tipped the church from its foundations and set it careening upon the molten river.”

“Straightaway, the bell, which hung in an open steeple, began ringing. It pealed above the roar of the flames and the grinding of the blazing substance surging onward.”

“A dozen doleful strokes of the iron tongue echoed farewell before it fell from the cross beam ringing its own requiem.” (Father Eugene Oehman, Honolulu Advertiser, July 31, 1932)

A memorial to the church was erected; the plaque on the monument reads “1926 Hoopuloa Catholic Church.” “Under the cross, 25 feet below the surface is all that remains of a small Catholic church, over which the lava flowed without a moment’s halt.” (Honolulu Advertiser, July 31, 1932)

“The fiery lava engulfed the harbor and village of Hoʻopuloa, and now they are but a heap of pāhoehoe lava.” (Hoku o Hawaii, April 20, 1926)

“Families of Ho‘opuloa were forced out of their homes by the flow, and many eventually settles in Miloli‘i on state land. The displace families remained on the land although they had no legal title to the property.” (Hawaii Tribune Herald, July 10, 1985)

In 1932, St. Peter’s Catholic Church at Miloli‘i was built by Father Steffen to replace an earlier St. Peterʻs destroyed by the 1926 lava flow. (PaaPonoMilolii)

In 1982, the State Legislature passed Act 62 which designated 52.6 acres of state land to be leased to the refugees and the descendants of the Ho‘opuloa lava flow.”

The Act also created the criteria by which people could qualify fo5 65-year leases” Initial implementation of the Act took place July 12, 1985 with the signing of 12 long-term leases for families living on the designated property. (Hawaii Tribune Herald, July 10, 1985)

October 22, 2021 by Peter T Young Leave a Comment

Bombing the River of Fire

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