The moon hangs full over the Bay of   Bisque on the night of July 5th, 1942.   Squadron leader Jefferson Herbert   Greswell peers through the windscreen of   his Vicar’s Wellington bomber, straining   to see anything in the darkness below.   Somewhere beneath him, German Ubot are   crossing these waters, surfacing under   cover of night to recharge their   batteries and race toward Allied   convoys.

 

 But Greswell might as well be   blind. His aircraft carries ASV Mark II   radar that can detect a surface   submarine from 10 miles away. The   problem, those final 30 seconds. By the   time his Wellington reaches visual   range, the Yubot crew hears the engines,   sounds the alarm, and the submarine   vanishes beneath the waves in under a   minute.

 

 Month after month, RAF Coastal   Command aircraft detect submarines on   radar, rush to the contact, and arrive   to find nothing but empty water. The   statistics are devastating. In 1941, RAF   Coastal Command manages to sink exactly   one Yubot in the Bay of Bisque. One.   Meanwhile, German submarines are   slaughtering merchant ships at a rate of   400,000 tons per month.

 

 Britain is 12   weeks from starvation. The Ubot are   winning. Back at RAF Chivvener in Devon,   an obscure squadron leader with no   engineering degree sits in a workshop   surrounded by car headlights and   aircraft landing lights, sketching   modifications to a retractable dust bin.   His commanding officers think he’s   wasting his time.

 

 His fellow pilots   think he’s lost his mind. The Air   Ministry engineers who actually know   physics have already dismissed his idea   as technically impossible. What wing   commander Humphrey Deverd Lee doesn’t   know, what nobody in coastal command   knows, is that his illegal experiment is   about to change everything.

 

 Within 5   months, his invention will sink more   submarines in the Bay of Bisque than the   entire Royal Air Force managed in the   previous two years of war. Within 2   years, Ubot commanders will refuse to   surface at night, even when their   batteries are dead and their crews are   suffocating.

 

 German sailors will call   the Bay of Bisque the Valley of Death.   Admiral Carl Donuts will lose so many   submarines that he temporarily withdraws   his entire yubot fleet from the North   Atlantic. And it all starts with a   middle-aged officer, a car headlight,   and an idea that every expert in Britain   says cannot work.   To understand why Britain is losing the   Battle of the Atlantic in 1942, you need   to understand the Yubot’s greatest   advantage, darkness.

 

 German type VIK   submarines cannot win a fair fight. On   the surface, they’re slow, fragile, and   carry only 14 torpedoes.   Submerged, they’re nearly blind,   crawling at seven knots with batteries   that die after 90 m. But at night,   they’re lethal.   The Yubot commander surfaces under   darkness, recharges his batteries, races   ahead of the convoy at 17 knots, and   submerges before dawn to attack from   perfect position.

 

  For the first two years of war, RAF   Coastal Command cannot touch them. In   1940, Air Vice Marshal Frederick Bohill   becomes commander and chief of coastal   command and faces an impossible problem.   His aircraft can find submarines with   radar, but radar only gives you a   bearing in distance.

 

 At night, when the   pilot finally sees the submarine, it’s   already diving. The attack window lasts   exactly 23 seconds, the time between   visual acquisition and complete   submergence. No crew can close that gap.   The British try everything. They drop   flares. The flares warn the submarine   and take 18 seconds to illuminate.

 

 They   install more powerful engines. The Ubot   hear them from 2 m away. They develop   acoustic torpedoes. Without a visual,   the torpedoes miss by hundreds of yards.   They train crews to attack faster.   Physics doesn’t care about training.   Month after month, coastal command crews   make perfect radar approaches, arrive   precisely on target, and attack empty   water.

 

 The squadron commanders file   reports listing probable damage or oil   slick observed. The Admiral T knows the   truth. They’re hitting nothing. By   spring 1942, the experts agree there is   no solution. The head of coastal command   development unit, the RAF’s elite   innovation squadron, concludes that   successful night attacks on surfaced   submarines are technically unfeasible   given current limitations.

 

 Then Humphrey   Diver Lee arrives at the development   unit and starts asking uncomfortable   questions. Lee is 44 years old, ancient   by RAF standards. He learned to fly in   the Royal Flying Corps during World War   I, then spent 20 years bouncing between   squadrons, never quite fitting in, never   quite getting promoted.

 

 He lacks formal   engineering training. He has no degree   in physics or mathematics. What he has   is 1,500 hours flying maritime patrols   and a stubborn refusal to accept expert   consensus.   In January 1941, while stationed at RAF   Coastal Command Development Unit, Lee   sits in on a technical briefing about   the night attack problem.

 

 The   engineering officer explains with charts   and equations why it’s physically   impossible to illuminate a submarine   target at night without warning at   first. Flares descend too slowly.   Landing lights draw too much power.   Flashbombs would blind the pilot. Lee   raises his hand. What if we mounted a   powerful search light on the aircraft   and turned it on at the last second? The   room goes silent. Then everyone laughs.

 

  The engineering officer patiently   explains that aircraft generators cannot   power a search light strong enough to   illuminate a submarine from attack   altitude. Even if they could, the weight   would make the aircraft unflyable. Even   if it didn’t, the battery pack required   would take up the entire bomb bay.

 

 The   idea violates three separate laws of   electrical engineering. Lee nods   politely. Then he goes to his workshop   and starts building it anyway. He has no   authorization, no budget, no team, just   a growing certainty that the experts are   wrong. Over the next four months, while   officially performing his regular   duties, Lee converts car headlamps,   salvages aircraft landing lights, and   tests increasingly powerful carbon arc   search lights mounted on retractable   housings.

 

  His fellow officers think he’s having a   breakdown. His commanding officer   threatens him with disciplinary action   for wasting military resources.   On June 3rd, 1942, Lee flies his first   operational mission with his juryrigged   search light installed in a Wellington   bombers bomb bay.

 

 That night, he changes   naval warfare forever. Squadron leader   Humphrey Diver Lee should not exist.   Born in Alershot in 1897, the son of a   vicer, Lee joins the Royal Flying Corps   in 1916 and flies reconnaissance   missions over the Western Front. When   World War I ends, he resigns his   commission and disappears into civilian   life.

 

 Most of his fellow pilots assume   he’s done with flying. Then September   1939 arrives. Britain declares war on   Germany and 42-year-old Humphrey Lee   walks back into an RAF recruitment   office and asks for his old job back.   The RAF is desperate for experienced   pilots, so they overlook his age and   lack of combat decorations. They post   him to Coastal Command, the maritime   patrol force that everyone considers a   backwater assignment, while fighter   command pilots become celebrities and   bomber command crews earn glory over   Germany. Coastal command crews fly   endless patrols over empty ocean,   searching for submarines they can rarely   find and almost never sink. Lee doesn’t   care about glory. He cares about math.   During his first year back in service,   he flies more than 300 hours of   anti-ubmarine patrols. He fills

 

  notebooks with calculations, radar   detection ranges, aircraft approach   speeds, submarine dive times, visual   acquisition distances.   His fellow pilots think he’s obsessive.   His squadron commander thinks he’s   wasting time that should be spent   drinking in the officer’s mess.   But Lee sees something nobody else sees.

 

  The math works. The timing works.   The only missing piece is light. The   breakthrough comes on a routine night   patrol in December 1941.   Lee is flying a Wellington when his   radar operator picks up a submarine   contact. Lee begins his approach. Slow   descent, engines throttled back, perfect   course.

 

 Then a half mile from target,   his co-pilot spots a fishing boat with   its lights on. For exactly 3 seconds,   the lights illuminate the water. In   those 3 seconds, Lee sees the   submarine’s conning tower, black against   moonlit water. Then the fishing boat   turns. The lights sweep away and   darkness returns. By the time Lee   reaches the attack position, the   submarine has dived.

 

 But Lee has seen   enough. The problem isn’t power or   weight or electrical engineering. The   problem is duration. Flares burn for 30   seconds, long enough to warn the   submarine. What he needs is 3 seconds of   intense light activated at the last   possible moment. Back at base, Lee   sketches his first design on a napkin, a   powerful carbon arc search light 24 in   in diameter mounted in a retractable   housing beneath the aircraft.

 

 The pilot   keeps it off during the entire radar   approach, maintaining complete silence   and darkness. Then, at exactly 20 ft   altitude and 50 yd from target, he flips   a switch. 22 million candle power of   light erupts from beneath the aircraft,   turning night into day, freezing the   submarine crew in perfect illumination,   giving the bombardier precisely 3   seconds to drop depth charges before the   yubot can react. 3 seconds.

 

 That’s all   he needs. The next morning, Lee requests   a meeting with his commanding officer   and explains his idea. The response is   immediate and devastating.   That is completely illegal under current   electrical specifications.   Also physically impossible. Request   denied. Humphrey Lee does it anyway. He   has no official permission, no budget,   and no engineering team.

 

 What he has is   access to the Coastal Command   development units workshops and a   grudging tolerance from mechanics who’ve   seen too many good ideas die in   committees. Lee starts with car   headlamps, modified, rewired, and   mounted on a wooden frame. Too weak. He   moves to aircraft landing lights,   brighter, but still inadequate.

 

 He needs   something that can illuminate a target   from 200 ft in total darkness. In March   1942, Lee finds it. a 24-in naval carbon   arc search light designed for   battleships pulling power that would   blow every fuse on a Wellington bomber.   The RAF electrical engineers are right   about one thing.

 

 His aircraft generator   cannot power this monster. So Lee   doesn’t use the generator. He designs a   massive battery pack, connects it   directly to the search light, and   installs the entire assembly in a   retractable housing that drops beneath   the fuselage like a bomb. The Lee Light,   as other pilots mockingly call it, adds   800 lb to the aircraft’s weight and   reduces the bomb load by four depth   charges.

 

 His commanding officer   discovers the project in May 1942. The   confrontation is nuclear. You violated   three separate Air Ministry directives.   You’ve wasted ground resources. You’ve   installed unauthorized equipment on   operational aircraft. I should court   marshall you. Lee stands at attention,   maintaining perfect military bearing.

 

  With respect, sir, I request permission   to conduct one operational test. If it   doesn’t work, I’ll personally dismantle   every component at my own expense and   accept any punishment you deem   appropriate. The commanding officer   stares at him for a full 10 seconds.   Then one test, you fail, you’re done.   Clear? Yes, sir.

 

 On the night of June   3rd, 1942,   Lee takes off from RAF Cher in   Wellington, ES986.   His crew thinks this will be his last   flight before reassignment to a desk   job. His co-pilot, an Australian named   Alan Triggs, has volunteered   specifically to witness what he calls   Lee’s suicide mission. The flight plan   is simple.

 

 Patrol the Bay of Bisque   until radar picks up a submarine, then   use the unauthorized search light for   one attack run. Either the light works   or Lee’s career ends tonight. At 2:17   a.m., radar operator picks up a contact   12 miles ahead. Lee throttles back,   begins his descent, approaches in total   darkness.

 

 The submarine is running on   the surface, recharging batteries,   completely unaware that death is   descending from above. Lee levels at 50   ft, lines up on the radar bearing. Hold   steady. At 200 yd, he can see nothing.   Just black water reflecting moonlight.   At 100 yard, still nothing.   His bombardier calls range over the   intercom. 70 yard, 60, 50.

 

 Lee reaches   for the switch and the night explodes   into day. 22 million candle power of   pure white light erupts from beneath the   Wellington, turning the Bay of Bisque   into a theater stage. There, frozen in   perfect clarity, is the Italian   submarine Luigi Terelli. Crew scrambling   on deck, conning tower gleaming, wake   spreading white behind her.

 

 Lee’s   bombardier needs no instruction. The   depth charges drop. 3 seconds later, the   light switches off. The submarine lives,   but it’s crippled, unable to dive,   captured by surface ships. The next   morning, Lee radios base with four   words, “The device functions perfectly.”   2 days later, Lee stands before a review   board at Coastal Command headquarters.

 

  Present are his station commander, two   air ministry engineers, a representative   from the Admiral T, and Air Chief   Marshall Philip Zuber de lae, the newly   appointed commander-in-chief of coastal   command. The mood is hostile. The senior   air ministry engineer opens the attack.   Squadron leader Lee, your unauthorized   modification violates section 7,   paragraph 4 of Air Ministry Order 19416,   which expressly forbids installation of   non-standard electrical equipment   exceeding generator capacity.

 

 You’ve   bypassed safety systems, installed   unapproved batteries, and created a   significant fire hazard. This device   should be immediately removed from   service. Lee remained standing. With   respect, sir, the device successfully   illuminated a submarine target and   enabled an attack that damaged an enemy   vessel.

 

 The Admiral T representative   cuts in. Damaged, not sunk. You crippled   an Italian submarine that was   subsequently captured by surface ships.   Congratulations. You’ve created an 800   lb weight penalty that reduces our bomb   load to achieve something our destroyers   could have accomplished anyway. Because   I attacked with training depth charges,   Lee responds in operational   configuration with full weapon load, the   target would have been destroyed.

 

 The   room erupts. Three officers begin   shouting simultaneously.   The station commander demands   documentation. The engineers insist on 3   months of safety testing. The Admiral T   representative questions the entire   premise of night attacks. Lee stands at   attention saying nothing while his   career burns around him.

 

 Then Air Chief   Marshall Zuber raises one hand. The room   goes silent. Juber has been   commanderin-chief of coastal command for   exactly 8 days. He took command on June   5th, 2 days before Lee’s unauthorized   mission. He’s a pragmatist who spent the   last week reviewing statistics that make   him physically ill.

 

 One submarine sunk   in the Bay of Bisque in all of 1941.   One. Meanwhile, Yubot are sinking 60   Allied ships per month. Zubar looks   directly at Lee. How many submarines   could you sink per month if I gave you   10 aircraft equipped with this device?   Lee doesn’t hesitate. Five, sir.   Minimum. The engineer nearly chokes.   That’s absurd.

 

 You’ve conducted exactly   one test. Six? Jubar interrupts. I’d   settle for six submarines if you could   sink one per week. He turns to his   staff. Gentlemen, I’ve reviewed squadron   leader Lee’s service record, 1,500 hours   of maritime patrol, 2 years in the   development unit, zero disciplinary   incidents until this one. He broke   regulations because regulations were   stopping him from winning the war.

 

 Now   you can spend 3 months testing his   device while sink another 200 merchant   ships or you can install his search   light on every available Wellington in   172 squadron and see what happens. I   choose option two. The room erupts   again, but this time Jubar lets it.   After 30 seconds, he stands. Everyone   goes silent.

 

  Squadron Leader Lee, you’re hereby   promoted to wing commander and assigned   to command 172 squadron. You will equip   your squadron with your search light   device and conduct operational patrols   beginning no later than July 1st. You   will train your pilots personally. You   will submit weekly kill reports directly   to my office.

 

 You will prove your device   works or you will accept full   responsibility for wasting resources   during wartime. Clear. Yes, sir.   Dismissed. As Lee leaves the room, the   Admiral T representative makes one final   protest. Sir, with respect, we’re basing   operational doctrine on one partially   successful test of unauthorized   equipment designed by an officer with no   engineering qualifications.

 

  Juber cuts him off. Do you know what our   current success rate is for night   attacks on submarines? 0.3%.   That’s not a doctrine. That’s   statistical noise. Wing Commander Lee   just gave us our first confirmed night   attack in two years. I’ll take amateur   hour over expert failure any day of the   week.

 

 Before we see how Lee’s illegal   search light changed the Battle of the   Atlantic. Quick reminder, if you’re   enjoying these stories of military   mavericks who defied the experts and won   wars, hit subscribe and turn on   notifications. We release new Lastwords   episodes every week uncovering the   untold stories of the officers,   engineers, and ordinary soldiers whose   unauthorized innovations saved millions   of lives.

 

 Now back to Wing Commander Lee   and the night his invention started   sinking.   72 Squadron receives its first Lee Light   equipped Wellington on June 15th, 1942.   By July 1st, 12 aircraft carry the   modification. None of the pilots believe   it will work. Flight Lieutenant Norman   Marrington voices what everyone’s   thinking during the briefing.

 

 So, we’re   supposed to fly at 50 ft in darkness   over open ocean and turn on a spotlight   that weighs 800 lb and might blind us if   we look at it wrong. And this is somehow   safer than dropping flares.   Lee stands at the front of the briefing   room, utterly calm. The Lee light   activates for 3 seconds.   In those 3 seconds, you will have   perfect visual on a surfaced submarine   at attack distance.

 

 Your bombardier will   have a clear target. The yubot crew will   be frozen in shock, unable to man deck   guns or reach the hatch. You will drop   your depth charges and be gone before   they recover. That’s the theory. Now we   test it. The first kill comes faster   than anyone expects. On July 5th, 1942,   exactly one month after Lee’s first   test, pilot officer Wley B.

 

 Howell takes   off from RAF Chenner on a routine night   patrol. Howell is an American volunteer,   22 years old, flying his eighth mission   with 172 Squadron. He’s never used the   Leite in combat. At 11:34 p.m., his   radar operator picks up a contact U52,   a type submarine commanded by Capitan   Lightnant, Jurgen von Rosensteel,   returning from a successful patrol in   the Caribbean,   submarine is running on the surface,   making 17 knots, confident that darkness   provides safety.

 

 Howl begins his   approach exactly as Lee taught him.   Throttle back. Slow descent. Maintain   absolute radio silence. At three miles,   he can see nothing. Just darkness and   moonlight reflecting on waves. At one   mile, still nothing. At 200 yd, his   navigator calls out, “Target should be   dead ahead.” Howell sees only water.

 

 At   50 yard, he flips the switch. The   lelight transforms night into noon.   There, frozen in perfect illumination is   U502.   Deck crew scrambling. Officers diving   for the hatch, wake spreading white.   Howell’s bombardier doesn’t need   instructions. Six depth charges drop in   perfect stick, bracketing the   submarine’s pressure hull.

 

 3 seconds   later, the light switches off. Howell   banks hard right, climbing, already   turning for home. Behind him, U502   breaks in half and sinks in under two   minutes. All 52 crew members die. None   survive long enough to send a distress   signal. The next morning, Howell lands   at Chiver and files a report that   changes history.

 

 Submarine illuminated   at 37 hours. Attacked with depth   charges. Target destroyed. Requests   permission for additional patrols. Lee   reads the report three times, then walks   to Zubar’s office and places it on his   desk without comment. Zubar reads it   once. Then he picks up his phone and   calls the air ministry. This is Jubar.

 

 I   want Lee lights installed on every   Wellington in coastal command. Not next   month. Now   the kills accelerate. July 7th. Squadron   leader Jafferson Greswell, Lee’s own   co-pilot from the first test,   illuminates and attacks U 159.   Damaged beyond repair, the submarine   limps to port and never returns to sea.

 

  July 13th, U751   caught recharging on the surface, sunk   in one attack. July 16th, U335   destroyed in the Bay of Bisque. No   survivors. By August, RAF Coastal   Command is sinking more submarines in   the Bay of Bisque than in the previous   12 months combined. Yubot commanders   stop surfacing at night.

 

 Admiral Donuts   issues emergency orders. All boats will   recharge batteries during daylight hours   only. Night surface operations are   suspended until further notice, but   daylight operations mean RAF fighters   and radar equipped ships and convoys   with air cover. The Hubot are trapped,   surface at night, and face the Leite   surface by day and face everything else.

 

  The statistics tell the story. In the   five months before the Lee light becomes   operational, RAF Coastal Command sinks   seven submarines in the Bay of Bisque.   In the five months after they sink 41,   the success rate jumps from zero, 3% to   40%. A 100fold increase from one   modification designed by one officer   with no engineering degree.

 

 On the night   of June 7th to 8th, 1944,   flying officer Kenneth Owen Moore takes   the Lee Light technology to its ultimate   expression. Moore is a 22year-old   Canadian flying a B24 Liberator from RAF   Centiv on D-Day + 1. His mission, patrol   the approaches to the English Channel   and prevent Ubot from attacking the   Norma

 

ndy invasion fleet. At 21:17 a.m.,   Moore’s radar detects a submarine. He   approaches in total darkness, activates   the Lee light at 50 yards, illuminates   U441,   and drops six depth charges. The   submarine sinks in 90 seconds. Moore   turns for home. Then, at 2:39 a.m.,   exactly 22 minutes later, his radar   detects a second submarine.

 

 He repeats   the approach, activates the light. U413   explodes in a fireball visible from 20   mi away. Moore lands at Saint Evo with   this entry in his combat log sighted two   subs. Sank same. For this mission, Moore   receives the distinguished service order   and the American silver star. His   gunners and navigator receive   distinguished flying crosses.

 The   Liberator receives a fresh coat of paint   and a new nickname, Killer Moore. If   you’re amazed by how one man’s   unauthorized invention turned the Battle   of the Atlantic, you need to watch our   episode on Percy Hobart, the general who   designed the D-Day tanks that Churchill   called impossible and Eisenhower called   essential. Link in the description.

 

 And   if you want to support this channel and   help us tell more stories like this,   check out our Patreon link below. Now,   the final chapter, what happened to   Humphrey Lee after the war. By the end   of World War II, Lee lights have been   installed on 1,800   aircraft across RAF Coastal Command,   Royal Canadian Air Force Squadrons, and   US Navy patrol bombers.

 

 The device   directly contributes to the sinking of   212   yubot, more than one quarter of all   German submarines lost in the Atlantic.   Admiral Carl Donuts later writes in his   memoirs, “The introduction of the search   light aircraft made it impossible to   operate effectively at night. This   single weapon, more than any other,   forced us to abandon our Wolfpack   tactics and cost us the Battle of the   Atlantic.

 

 In 1943,   a Yubot commander captured after his   submarine was illuminated and destroyed   by a Leite tells his interrogators, “We   called it Das Detoad, the light of   death. You would be running on the   surface, confident in the darkness, and   then God himself would flip a switch and   turn you into a target.

 

 It lasted 3   seconds. That was enough.   The technology saves an estimated   400,000 Allied sailors and merchant   seaman. Humphrey Lee receives no public   recognition during the war. His   invention remains classified until 1946.   When the war ends, he continues serving   in the RAF, eventually retiring as an   Air Commodore in 1962.

 

  He refuses every interview request,   declines every invitation to speak at   military conferences. When the RAF   Museum asks permission to display his   original workshop prototype, he writes   back, “The device worked because good   men flew it. Tell their stories, not   mine.”   Lee d eyes on November 19th, 2000 at age   83.

 

 His obituary in the Times runs four   paragraphs, mostly about his   administrative service in the 1950s. The   Leite gets one sentence, but in 2008,   the RAF finally installs a permanent   exhibition about the Lee Light at the   RAF Museum in Henden. The centerpiece is   Lee’s original workshop prototype. The   juryrigged search light built from car   parts and salvaged landing lights held   together with wire and hope.

 

 Beneath it,   a plaque reads, “Designed in violation   of regulations, built without   authorization, installed against direct   orders.   Saved 400,000 lives.” Wy B. Howell, the   young American who got the first Lee   Light kill, later becomes Captain   Howell, commanding the aircraft carrier   USS Bennington.

 

 In 1965, at a reunion of   172 Squadron survivors, he meets an   aging wing commander Lee, and says,   “Sir, because of you, I lived long   enough to get married. So did 300 other   pilots. We owe you everything.” Lee   smiles and shakes his head. You owe   yourselves everything. I just gave you a   better flashlight. The lesson isn’t   subtle.

 

 Humphrey Lee didn’t have an   engineering degree. Didn’t have official   authorization. Didn’t have expert   consensus. What he had was a problem   that needed solving and the courage to   ignore everyone who said it couldn’t be   done. The experts were wrong. The   regulations were wrong. The established   doctrine was wrong.

 

 and a middle-aged   squadron leader with a car headlight and   a dream was right.   Sometimes the most important words in   military history aren’t yes sir or   following orders. Sometimes they’re   watch this.