Midnight Signals Case Files
Companion to Episode: The Battle of Los Angeles: 1,400 Rounds into the Sky
At 3.06 on the morning of 25 February 1942, four anti-aircraft batteries opened fire over Santa Monica. Other guns joined as reports of aircraft came in from across Los Angeles. Searchlights swept the blacked-out sky, and shell bursts hung in their beams. On the ground, people watched from gardens and hilltops as a city that had spent eleven weeks preparing for attack appeared to be fighting one.
Pieces of metal came back down through roofs, windows and parked cars. The fighters stayed on the ground while the batteries kept firing. By the time the guns fell silent, they had sent 1,440 rounds of three-inch ammunition into the sky without bringing down an identifiable aircraft.
On the evening of 23 February, a Japanese submarine had shelled oil installations farther up the California coast and escaped. An attack on Los Angeles was something commanders had to take seriously. Now their gunners had fought for more than an hour, and the reports arriving at headquarters scarcely agreed on what they had been shooting at.
The paid companion continues with wartime accounts, an illustrated chronology and a reading guide to the original sources.
Along the coast
The submarine attack had come more than a hundred miles north of Los Angeles. At 7.05 in the evening on 23 February, the Japanese submarine I-17 surfaced about 2,500 yards off Ellwood, near Santa Barbara. President Franklin Roosevelt had begun a radio address five minutes earlier. The submarine’s deck gun sent thirteen 5.5-inch shells toward oil installations along the shore.
The damage was slight. Piers and wells were hit, but the gasoline plant that appears to have been the intended target was missed. Pursuit aircraft and three bombers searched for the submarine without finding it. The submarine had fired on the California coast while the president was speaking on the radio, and escaped.
The city was dense with targets that would have interested an enemy planner. Nearly half of American military aircraft production came from eight plants in the Los Angeles area. The port, shipyards and oil industry sat within the same coastal region. When Pearl Harbor was attacked on 7 December 1941, the old assumption that Hawaii and the Pacific Fleet formed a secure barrier had collapsed in a morning.
Troops and guns moved west quickly, but readiness on paper hid shortages of equipment and trained operators. The Army history counted fourteen anti-aircraft regiments on the coast by early 1942, yet the system joining radar, observers, information centres, guns and fighters was new. Along 1,200 miles of coastline, ten radar sets were supported by about 2,400 civilian observation posts. There was no American ground-control equipment able to guide night fighters with British precision, no airborne interception radar in the Pacific Coast aircraft and no dependable way to identify every friendly return.
British radar scientist Robert Watson-Watt inspected the West Coast defences in January. His report found weak organisation wrapped around equipment that was itself limited. He warned against seeing radar either as an all-knowing eye or as an unreliable toy. It could give dependable warning, but only if trained people followed a contact continuously and passed it through a system that understood what the instrument could and could not see.
The reports coming in
Naval intelligence warned on the 24th that an attack might come within ten hours. Reports of flares and blinking lights near defence plants led to an alert at 7.18 that evening. It was cancelled at 10.23.
At about two in the morning, coastal radar acquired an unidentified return 120 miles west of Los Angeles. Anti-aircraft batteries were alerted at 2.15 and brought to green alert soon afterward. The contact came toward the coast, then disappeared from the radar picture. The regional controller ordered the blackout at 2.21. Sirens sounded across the county. Wardens moved into the streets while drivers pulled over or continued through intersections without lights.
At 2.43, aircraft were reported near Long Beach. A few minutes later, a Coast Artillery colonel reported about twenty-five planes at 12,000 feet. At 3.06, a balloon carrying a red flare appeared over Santa Monica and four batteries opened fire. Other batteries joined as reports moved east and south.
The Army Air Forces history records estimates ranging from one aircraft to several hundred. Estimated altitudes ran from a few thousand feet to more than 20,000. Speeds ranged from very slow to above 200 miles an hour. Some observers also reported a solid shape held in the beams, distinct from the formations described by others.
In the letter attributed to artilleryman Charles Patrick that the episode recounts, he described six aircraft flying in formation. Correspondents Ernie Pyle and Bill Henry, whose observations appear in the official history, watched the barrage and could not make out an airplane. Even the acting anti-aircraft brigade commander changed his mind about what he had seen. At first he counted fifteen aircraft; later he decided he had been looking at smoke.
What the guns put into the sky
The three-inch shells used above Los Angeles weighed about 12.8 pounds apiece. They were fitted to burst at a chosen time and throw fragments through the path of an aircraft. Each battery aimed ahead of its target, timing the explosions to scatter fragments where the aircraft was expected to be.
At night, crews trained several searchlights on a target so the director crew could estimate its height, course and speed. Once shells began bursting in those beams, every part of the system grew harder to read. Smoke reflected light. A burst could look like a moving point as the beam shifted. Tracer fire supplied fresh lights. Reports from neighbouring batteries reached commanders who were already receiving calls from civilians.
The fragments from those explosions fell onto houses, factories and roads. They punctured roofs and cars. News photographs showed a garage damaged in the barrage. The official history recorded damage from falling metal, heart failure and traffic accidents in darkened streets. Later summaries commonly count five civilian deaths: three in road accidents and two following heart attacks. None was killed by an enemy bomb.
The fighters remained on the ground. That decision has often been treated as evidence that commanders knew the object could not be an aircraft, but the contemporary logic was more cautious. Fourth Interceptor Command wanted to know the size and direction of a raid before committing a limited force at night. Sending pilots into a sky full of friendly anti-aircraft fire, without dependable ground-controlled interception, could add aircraft to the confusion and put American crews in the shells’ path.
Two departments, two answers
Navy Secretary Frank Knox spoke first. At a press conference on 25 February, he said there was no evidence of enemy aircraft and called the episode a false alarm caused by wartime nerves. He also said coastal industries remained vulnerable, which made the reassurance sound less settled than the headline it produced.
The Western Defense Command’s first message to Washington had already begun to discount some reports. The Fourth Air Force believed no aircraft had been over the city. The Army did not release that conclusion. Local commanders spent the day hearing witnesses and changed their assessment. By the 26th, the War Department believed one to five unidentified airplanes had been present.
Secretary of War Henry Stimson carried that view to the public. The aircraft, he suggested, might have been civilian machines flown by enemy agents from hidden fields in California or Mexico. They might instead have been light observation planes carried by Japanese submarines. Their purpose could have been to locate gun positions or damage morale. No secret runway, captured pilot, submarine launch record or aircraft fragment was produced to support them.
The press noticed the gap. The Los Angeles Times demanded a full explanation. Representative Leland Ford of Santa Monica asked whether the event had been a practice raid, a mistaken identification, a deliberate scare or political groundwork for moving war industries away from Southern California. Editorial writers asked the simplest operational question: if real hostile aircraft had crossed the city, why had no American fighter gone up to identify them?
The balloon answer
In the Army Air Forces chronology, a balloon carrying a red flare appears at the moment the first batteries opened fire. Meteorological balloons were known to have been released over Los Angeles. Anti-aircraft units were later criticised for wasting ammunition on targets moving too slowly to be aeroplanes.
A suspended flare could have been mistaken for an aircraft marker or navigation light. Smoke and illuminated shell bursts could account for a portion of what came next. The official history, completed after the war, judged that balloons may well have started the alarm and that smoke made careful observation difficult.
The offshore radar contact had vanished before the shooting, according to the Army history. The published account does not connect that return to the balloon over Santa Monica. It also lacks the raw radar plots needed to establish whether the operators had tracked an aircraft or received a spurious return.
Witnesses also described formations, fast-moving lights and a large shape held in several beams. Those reports cannot all describe the same slow object in the same place. Shell bursts, smoke and mistakes passed from observer to observer may account for some of them; the accounts alone cannot establish how many objects were present or what they were.
The photograph people remember
The best-known image shows beams crossing beneath a pale, saucer-like mass while bursts stipple the sky around it. It is often presented as a photograph of the object that survived 1,440 rounds.
The Los Angeles Times printed a heavily worked version on 26 February 1942. Newspaper art departments then routinely painted, burned and heightened photographs so shapes would survive coarse reproduction. The published image deepened the black sky, strengthened the beams and created a bright white patch where they met. A much softer print later found in the Times photographic archive shows light and smoke, but no comparably crisp body.
Before the saucer had a name
In February 1942, witnesses did not share the vocabulary that later formed around UFOs. Kenneth Arnold’s 1947 report near Mount Rainier helped popularise “flying saucer” five years afterward. Roswell came later that summer. Readers looking back at the Los Angeles photograph now had a name for the shape at the centre of the beams.
The disagreement between the Army and Navy was already in the newspapers of 1942. Later accounts returned to it alongside the photograph and the failure to bring down an aircraft. An explanation of why the batteries fired became a story about a machine that had survived their fire, with the white patch in the photograph taken as its visible body.
The fear on the ground
Six days before the barrage, Roosevelt signed Executive Order 9066. The order authorised military commanders to exclude people from designated military areas. It did not name Japanese Americans, but that is how it was applied on the West Coast. Families lost homes, businesses and freedom as about 120,000 people of Japanese ancestry were removed and incarcerated, most of them U.S. citizens.
Anti-Asian racism, economic interests and military pressure had already led to Roosevelt’s decision before the barrage. The air raid then gave people fresh grounds for suspicions already being directed at Japanese American residents.
The official Army history describes agitation for removal in the month before the raid and repeats reports that Japanese Americans had predicted demonstrations connected to Roosevelt’s address. Stimson’s theory of enemy agents flying from secret fields put imagined collaborators inside California. No evidence from the raid established that Japanese American residents directed aircraft or signalled submarines.
After the all-clear
The all-clear sounded at 7.21, more than three hours after the last firing. Four aircraft had been reported shot down during the barrage. One was said to be burning at a Hollywood intersection. By morning, none of those reports had produced wreckage. The damage that could be found on the ground came from the city’s own shells; no enemy bomb had fallen.
After the war, Japanese authorities said that no aircraft had been sent over Los Angeles that night. Japanese submarines could carry small reconnaissance planes, and one was later flown over Oregon, but no surviving Japanese operational record places such a flight above the city on 25 February. The official American history gave weight to the balloon and to the smoke that spread through the beams once the guns opened fire. The offshore radar contact remained unidentified. So did the slow object described by some witnesses, including trained personnel, whose observations could not be matched to a recovered aircraft or a continuous radar track.
Chronology of the alarm
7 December 1941
Japan attacks Pearl Harbor. West Coast commanders raise defence readiness while reports of enemy ships and aircraft begin arriving almost daily.
Early radar equipment, thinly trained crews and fear of another carrier strike shaped every later alert.
19 February 1942
Roosevelt signs Executive Order 9066, authorising military exclusion areas. It becomes the basis for removing and incarcerating Japanese Americans from the West Coast.
The order came before the Battle of Los Angeles; the barrage did not cause it.
23 February, 7.05–7.25 p.m.
The Japanese submarine I-17 shells the Ellwood oil installations near Santa Barbara. Thirteen rounds cause minor damage and no casualties.
24 February, daytime
Naval intelligence warns that an attack may come within ten hours. Military and civilian observers are already primed for renewed action.
24 February, 7.18–10.23 p.m.
Reports of flares and lights near defence plants prompt an alert, which is later lifted.
25 February, about 2.00 a.m.
Coastal radar acquires an unidentified return about 120 miles west of Los Angeles and tracks it toward the coast.
The contact disappears before the later barrage and is never identified in the published record.
2.15–2.21 a.m.
Anti-aircraft batteries are alerted, then brought to green alert. The regional controller orders a blackout at 2.21.
2.43–3.00 a.m.
Aircraft are reported near Long Beach. A Coast Artillery colonel reports about twenty-five planes at 12,000 feet.
3.06 a.m.
A balloon carrying a red flare is reported over Santa Monica. Four batteries open fire and other guns join.
The Army’s postwar history treats this as the likely beginning of the shooting.
3.06–about 4.14 a.m.
Reports multiply across the region. Gunners expend 1,440 rounds of three-inch ammunition. No bomb is dropped and no aircraft wreckage is recovered.
7.21 a.m.
The all-clear sounds and the blackout is lifted.
25 February, afternoon
Navy Secretary Frank Knox calls the episode a false alarm. The Army continues interviewing witnesses.
26 February
The War Department says one to five unidentified aircraft may have been present. Stimson proposes secret civilian aircraft or submarine-launched planes.
1945 and after
Japanese authorities say no aircraft were sent over Los Angeles. Official American histories give increasing weight to a weather balloon, shell bursts, smoke and wartime nerves.
1947 onward
The flying-saucer era gives the case a new vocabulary. The worked newspaper photograph becomes its defining image.
Sources and image credits
Reading and viewing
The episode. “The Battle of Los Angeles: 1,400 Rounds into the Sky”, Midnight Signals, released 14 September 2026. The full Substack transcription of the released 16-minute episode was accessed for this companion. It recounts a letter attributed to artilleryman Charles Patrick, who described six aircraft in formation. No archival catalogue entry or contemporary publication for that letter was located during preparation; it is retained as episode witness material, not independent confirmation of a flight.
The closest official narrative. William A. Goss, “Air Defense of the Western Hemisphere,” in Wesley Frank Craven and James Lea Cate, eds., The Army Air Forces in World War II, Volume I. Pages 282–286 give the alert times, 1,440-round total, official disagreements and postwar balloon assessment. The online edition reproduces a U.S. government history.
The wider defence record. Stetson Conn, Rose C. Engelman and Byron Fairchild, “Continental Defense,” chapter 4, in Guarding the United States and Its Outposts. This official Army history covers the I-17 attack, West Coast troop strength and the unsettled state of the warning system.
A California collection guide. California State Library, “The Battle of Los Angeles”. A concise route into the state library’s account, built around the Army Air Forces history.
The public experience. Lorraine Boissoneault, “The Great Los Angeles Air Raid Terrified Citizens, Even Though No Bombs Were Dropped”, Smithsonian, 19 January 2018. Useful for civilian reaction and the incident’s long afterlife.
The two versions of the photograph. Historian Brett Holman’s “New light on the Battle of Los Angeles” reproduces and discusses the less-worked archive print alongside the version published in 1942. Useful for examining the changes to the beams, sky and central patch of light.
The order already in force. National Archives, “Executive Order 9066: Resulting in Japanese-American Incarceration”. The record gives the signing date, the order’s language and its use against Japanese Americans.
How the saucer vocabulary arrived. Smithsonian National Air and Space Museum, “Reports of UFOs: 1947 Roswell Incident”. The museum places Kenneth Arnold’s 1947 report at the beginning of the flying-saucer wave that later absorbed the 1942 case.
Image credits
1. Battle of Los Angeles map. Dbenbenn and Onhigan, 2021. Wikimedia Commons collection record and public-domain dedication. Rasterised here for consistent display. The plotted reports are a guide and do not prove a single flight path.
2. Japanese submarine I-17. Ryu Matsumoto, Imperial Japanese Navy photograph archive, 19 July 1939. Wikimedia Commons collection record and public-domain basis. The image shows the submarine at launch, not the Ellwood attack.
3. SCR-270 radar set. Harold Zahl, U.S. Army Signal Corps. Wikimedia Commons collection record and U.S.-government public-domain basis. This is the same early-warning radar model used at Pearl Harbor; it is an equipment illustration, not the Los Angeles station.
4. Anti-aircraft gun crew. Office of War Information collection, December 1941 or January 1942. National Museum of the U.S. Navy/Wikimedia Commons record and U.S.-government public-domain basis. The crew is in New York, not Los Angeles.
5. Searchlights over Los Angeles. Photographer unidentified, February 1942. Wikimedia Commons item record, sourced there to Associated Press. The record identifies U.S. public-domain status through nonrenewal. Its date field says 24 February; the barrage occurred before dawn on 25 February. The reproduced file is 600 × 372 pixels.
6. Los Angeles evacuation. Russell Lee, War Relocation Authority, 1942. Library of Congress catalogue record and FSA/OWI public-domain statement. Soldiers assist Japanese American families leaving for Owens Valley.