CHAPTER SIX

  _Invisible Killer_

  With its four engines singing a song of power that would be sweet musicto the ears of any pilot the Flying Fortress thundered its waysouthwestward through the night-darkened Pacific sky. The aircraft wason the automatic pilot, and both Dawson and Freddy Farmer sat outwardlyrelaxed at the controls, but inwardly on the alert for the slightestmiss in any of the engines, or for anything that would indicate that allwas not as it should be. The Los Angeles Air Forces base was six hoursbehind them. Another six and they should be over Hickam Field, on OahuIsland, waiting for the permission signal to land.

  Suddenly, with a little chuckle, Dawson broke the silence that hadexisted for some minutes between them. Freddy Farmer glanced across athim with a questioning frown.

  "What now, Dave?" he asked.

  "Us," Dawson replied, and chuckled again. "I guess we're getting old,Freddy. I mean, we seem to scare pretty easy these days. And I'll admitthat I was as jittery as a hen on a hot stove until we got this Fortressoff the ground, and into the air. I actually had little chills runningup and down my back, as though I expected to feel a nice white-hotbullet cut into it at most any second. But heck! Not a thing happened. Ididn't see a thing that looked Jap, did you?"

  "No, I didn't," Freddy Farmer replied. "But my imagination certainlygave me a lot of trouble. Every time one of those mechanics put a bag ofmail aboard, or a case of those medical supplies we're taking over, Ihad a brief moment of feeling positive that he was a Japrat, buck teeth,and all. But, as you say, nothing happened."

  "Yeah," Dawson murmured, and peered out at the wall of night darknessthat completely circled the aircraft. "Just another airplane ride forus. And that doesn't make me mad at all. I wonder if the field radioedDago when we got off? Vice-Admiral Carter sure sounded plenty worried onthat phone."

  "Yes, he ..." Freddy Farmer said, and then cut himself off short.

  "What's the matter, Freddy?" Dawson asked, as a sudden clammy sensationrippled through his chest.

  "Down there," young Farmer replied, and pointed off and down to theleft. "Is that a light blinking, or am I seeing things?"

  Dawson leaned forward slightly and stared in the direction of Freddy'spointing finger. A couple of seconds later he saw the unmistakableflashing of a light. Because of the Flying Fortress's altitude it was nomore than a pin-prick of light. But it was very real just the same.

  "Yes, I catch," he finally grunted. "Probably one of our shipsrequesting us to flash our identification signal. The heck with them.They should know that no Jap plane could possibly be in this neck of thewoods."

  "But what if they open fire, if they have flak guns aboard?" Freddymurmured as they both continued to watch the blinking light far below."There's such a thing as a lucky hit, even at our altitude."

  "Okay, if you insist, pal," Dave grunted, and started to reach out hishand. "But ... Hey! Did you catch that, Freddy? That looked like the oldSOS to me."

  "It was!" young Farmer replied with a nod, and hunched forward a bitmore on his co-pilot seat. "Wait a minute! He's trying to sendsomething else. K ... D ... J? K, D, J? Wonder what that means?"

  "Take a look in that signal book in the pocket beside you," Dawson said."I think those things have surface ship signals as well as aircraftsignals. Take a look anyway."

  It didn't take young Farmer more than a few seconds to find what he washunting for. Excitement rang in his voice as he spoke to Dawson.

  "Here it is, Dave!", he cried. "K, D, J. Attacked by enemy force! Pleasegive assistance."

  "Attacked by enemy force?" Dawson echoed sharply, and squinted hard downat the still blinking pin-point of light. "Must be some ship nailed by aJap submarine. Maybe we'd better slide down for a look. At least thatshould scare the Jap sub away, if there's one still lurking around. AJap submarine east of Pearl Harbor? Well, what do you know? Get back atthe port gun slot, Freddy, just in case we get the chance to take acrack at something. And I think I'll drop a flare so's we can get a goodlook."

  "No, don't, Dave!" young Farmer said sharply, and gripped his arm asthough to restrain him.

  "No?" Dawson echoed. "Why not? We won't be able to see much in thisdark. And certainly not a Jap submarine, if there's one on thesurface."

  "I know," Freddy said with a shrug. "But I've got a funny feeling. Aflare would light us up nicely, too, you see? Let's play it cautious,what say?"

  "Okay, okay," Dave said with a grin. "Maybe you have got somethingthere. Anyway, get back to the port gun slot, and I'll slide us down abit."

  "Right you are," Freddy said, and slid out of the co-pilot's seat andmade his way aft.

  Dawson had already throttled the four engines, and was sending theFlying Fortress sliding down through the Pacific night sky in a seriesof ever widening circles. He circled to port so that he couldcontinually keep his eye on the blinking light that grew bigger andbigger as the Fortress lost altitude. And the light kept on sending twosets of letters. The standard SOS and KDJ. A couple of times Dawson wastempted to signal back that they had caught the signals and were comingdown to find out what they could do to help. Each time, though,something seemed to stop him from showing the bomber's signal light. Hehad even switched off the cockpit light, and he was not allowing theengines to show any exhaust plumes that might reveal the Fortress' exactposition.

  "Guess I must be as jumpy as Freddy!" he grunted to himself. "But maybeit is best to play it safe, even if it must be one of our surface shipsdown there. There's no telling what can happen next in this cockeyedworld. And, boy, Freddy and I should sure know that by now. Yeah! Sowe'll sneak down and only let them know where we are by what sounds ofour engines they can catch."

  With a nod for emphasis, he flipped up the switch of the Fortress'inter-com system, and put his lips to the mike.

  "Have you hooked this thing up at your end, Freddy?" he asked into whathe guessed was a dead wire.

  But he was wrong. Young Farmer's voice was in his earphones instantly.

  "Yes, Dave. Can you see anything yet, besides the signal flashes?"

  "Nope," Dave replied. "But we're only at eight thousand now. Whoever'ssignalling is sure a persistent guy, isn't he? Is he so deaf he can'thear us coming down, do you suppose? You haven't caught any differentsignals, have you?"

  "The same two groups of signals over and over again," young Farmerreplied. "I fancy they'd stop, though, if we acknowledged. But Iwouldn't, Dave, if I were you. I still have a funny feeling about thisbusiness. It just doesn't seem quite right to me, but blessed if I knowwhy. I ..."

  Freddy never finished the rest. He never did for the reason that at thatexact moment a stab of orange red flame showed down by the blinkinglight. Dawson saw it and had only time to stiffen slightly in the seatbefore the night darkness all about the Fortress was lighted up asbrilliantly as high noon by a bursting star shell. And hardly had thewhite light virtually exploded in front of Dawson's face before the airall about was filled with the roaring thunder of bursting flak shells.

  For the infinitesimal part of a split second Dawson sat as a man struckdead. Then with a wild yell he shook himself out of his trance, rammedall four throttles wide open and threw the Flying Fortress up and aroundin a steep climbing turn. The first star shell had died out by then, buta second and a third one had taken its place, and the silvery brilliancethat seemed to flood everything was punched red and orange here andthere by flak shells seeking out the Fortress.

  "A trap, a trap, and I all but flew right down into it!" Dawson yelledangrily. Then as he looked down over the side of the plane, cold rageshook him from head to toe. "Freddy!" he shouted into his inter-commike. "Do you see what I see, Freddy? It's a submarine. A Jap submarine.The dirty rats! They pulled us almost down to the muzzles of theircocked anti-aircraft guns. The stinkers. If they'd waited just a minutelonger they couldn't possibly have missed. Hey, Freddy! You okay, kid?Did we get hit by anything?"

  "Not that I can see from here!" young Farmer called back. "But I guessmy feeling meant
something, what? The dirty beggars! I wonder how oftenthey've pulled this killer's trick on lone planes flying out to theIslands? Praise be they're rotten shots. Look! They see that they can'tget us now, so they're preparing to dive. They're ... I say, Dave! Whatthe devil's wrong? Is the plane out of control?"

  "Out of control, nothing!" Dawson roared as he sent the huge bomber overon wing, and down. "I mean it to go this way. Show me some of that sweetshooting of yours, Freddy! I'll take you right down on top of them, andnuts to their flak fire. Boy! If we only had a depth charge or two, or abomb. But give them what you can, Freddy!"

  "Right you are!" young Farmer's voice echoed in Dawson's earphones."Just get me a little lower, and level us off. I'll make the dirtyblighters dance."

  The Jap submarine's fire was still pretty heavy, but Dawson sent theFortress thundering right down through it as though it didn't evenexist. The submarine was getting under way, and one by one the deck gunsceased fire as the gun crew quit them and scampered along the wet decksto the conning tower. Two or three of them reached the ladder leading upto the bridge, but that's as far as they got. Freddy Farmer's port-slotfifty-caliber guns started to speak their piece, and the running Japswere knocked flat as though invisible hands had jerked their feet outfrom under them. Those behind the ones that fell kept on coming like mencrazed by fear who didn't know any better. Anyway, they ran straightinto the withering fire that had cut down the others, and their rottenlives were promptly snuffed out in exactly the same way.

  Not a gun fired back at the Fortress, now, as Dawson kept circling thetarget so that Freddy could work his slot guns continuously. Theundersea craft was driving hard through the water with its diving planesundoubtedly all set to be run out for a crash dive the instant thosewho survived the death that sprinkled the deck were inside and theconning tower hatch closed tight. But Freddy Farmer was seeing to itthat none of those scampering Japs on deck survived his withering fire.He relentlessly cut them down one after another like tenpins. And thenas Dawson veered the Fortress even closer to the trapped submarine,young Farmer sent a hail of explosive bullets practically straight downthe still partly opened conning tower hatch.

  "Have some of those, you filthy beggars!" Dave heard Freddy's voicescreaming over the inter-com. "Pull a trick like that on us, what? Well,how do you like some of the same? How do you like it, what?"

  "They don't like it even a little bit, pal!" Dawson shouted impulsivelyinto his own flap mike. "Not even a ... Hey! Ye gods! You've hitsomething, Freddy!"

  Hit something was right! A column of livid red flame suddenly belched upout of the conning tower hatch. The silver light from the floatingexploded star shells had just about died away, but now the sky and thesea were bathed in a blood red glow as the column of flame mountedhigher and higher, and then fountained outward in all directions. Itcame so close to the circling Fortress that Dawson gasped out astrangled cry of alarm and quickly banked off in the opposite direction.As soon as he was clear of the area of falling fire he banked theFortress again so that he could look back at the doomed Jap submarine.

  And doomed it was. Even as he saw it again there was another violentinternal explosion that seemed to lift the craft clean out of the water.It actually seemed to hover motionless in mid-air for a moment, andalthough Dawson was not sure, he thought he saw the thing break in half,and both halves fall back into the water with mighty splashes, and thendisappear completely beneath the flame-tipped waves. At any rate, aninstant later the submarine just wasn't there any more. There wasnothing but a blazing whirlpool of oil to mark the spot where it hadbeen. There was not even a single piece of floating wreckage in thatever widening circle of blazing oil.

  "And that's one Tojo can sure mark off as gone for good!" Dawsonmuttered, and nosed the Fortress up for altitude. "What a way to die,even for a dirty Japrat."

  With a little shuddering shake of his head he took his gaze off theblazing patch of oil slick, and turned his attention forward.

  "Okay, Freddy, boy!" he called into his inter-com mike. "Come on upfront and get your cigar for hitting the bull's-eye. And how you did,pal. How you did!"

  There came no reply from Freddy over the inter-com, nor did the Englishyouth come up forward in person.

  "Hey, Freddy!" Dave shouted, this time even louder. "Can you hear me?Anything wrong back there? Hey, Freddy!"

  Ten full seconds of silence ticked by, and an eerie chill started toclose about Dawson's heart. Why hadn't Freddy at least answered if hewasn't coming forward just yet? Was something wrong? Had a chance shotfrom that rotten Jap submarine nailed old Freddy? But that couldn't be.He'd heard Freddy's port-slot guns still slugging away long after thelast gun on the submarine had gone silent. Then what was wrong?

  Those, and a hundred and one other torturing thoughts raced throughDawson's brain as he put the Fortress back onto the automatic pilot,unhooked his safety harness, and scrambled out of the seat and went aft.As he pushed through the door leading into the bomb bay he stopped deadin his tracks and then instantly dropped flat on his hands and knees. Asea of acrid smelling smoke had come swirling through the compartmentdoor opening, and although his own heart seemed to be pounding againsthis very eardrums he was able to hear the faint crackling of flames. Andhe could see that the swirling smoke inside the bomb-bay was tinted byfire.

  "Freddy! Freddy!" he bellowed at the top of his lungs. "Are you trappedin there? Can you hear me? Where are you, Freddy?"

  "Back here, Dave!" came the muffled reply through the swirling smoke."Give me a hand, quick. The mail sacks. The blasted things are on fire.Mind the bomb-bay doors, Dave! I've opened them to toss these thingsout. Give me a hand, Dave. I don't think I can make it alone. Blast!That thing's hot!"

  Long before Freddy Farmer had stopped speaking Dawson was crawlingthrough the door opening on his hands and knees. It was like crawlinginto the middle of a blast furnace. The acrid smoke stung his eyes andalmost blinded him. It seemed to pour down his throat and gag him, andhe was frightfully afraid that he might misjudge his movements and gohurtling down through the opened bomb-bay doors.

  But he did not misjudge, and after what seemed an eternity spent insidea hot stove, he reached Freddy Farmer, who was hauling smoking andflaming mail sacks along the floor of the compartment and then droppingthem down through the opened bomb-bay doors. Young Farmer looked like asmudged-faced ghost in the red glow of the burning sacks. His helmet andgoggles were gone, and his flying suit was badly scorched in a couple ofplaces.

  "What happened, Freddy?" Dawson choked out as he grabbed a smoking mailsack off the pile and hurled it down toward the night-shrouded Pacific."We stop some of their flak? But how the dickens did these sacks catchon fire?"

  "Don't know!" Freddy choked through the smoke. "Can't understand it.Just happened to look back in here to check if anything had been hit,and found the whole blasted place full of smoke. Saw a couple of stabsof purple light, and then the whole business broke into flame. Didn'tdare waste time calling you. Think the fire got the inter-com wires,anyway. Boy! Suppose I hadn't happened to look in here!"

  Dawson simply shuddered and dragged another sack off the pile. Hedidn't bother to make any comment. It was horrible enough just to thinkabout the whole rear end of the Fortress catching fire. Besides, therewas too much of the stinging smoke in his nose and throat to permit anyunnecessary talk. They still weren't out of danger. No, not by a jugful.At that very moment, as Dawson kicked a smoking sack toward the bomb-bayopening, a tongue of purple white light shot out of its heavy canvascovering. A hissing sound filled Dawson's ears, and then the mail sackwent tumbling down through the air. Dave's breath seemed to stick in histhroat, and his heart turn to stone, as the terrible realization came tohim. He heard Freddy Farmer cry out in stunned amazement but he couldnot have turned his head Freddy's way at that moment, even if not doingso had cost him his life. Half frozen with fear, he stood gaping at thebomb-bay opening down through which the flaming mail bag had justdisappeared.

  Then, snapping out of his tr
ance, he whirled around and practicallythrew himself at the three or four smoking mail bags left. Fire burnedhis hands a little, but he hardly felt the pain. His only thought atthat moment was to get every last one of those mail bags out of theplane. And a few moments later the last one of them went spinning downthrough the opening out of sight. By then an up-draft had cleared awaymost of the smoke. For a moment Dawson and Freddy Farmer stared at eachother in the pale glow of a single bulb in the compartment ceiling thathad not been reached by the flames. Then, as though still in a trance,Dawson reached out and pushed the button that closed the bomb-bay doors.And then the two of them more or less reeled back to the pilot'scompartment and dropped gasping for air into their seats.

  "The first aid kit, beside you, Freddy," Dawson finally managed to forcethe words from his lips. "Better get it out and use some of the tannicjelly on our hands. No sense taking chances. Good grief, Freddy! Therewere time fire bombs in some of those sacks. Somebody figured to make usbail out, and flame this thing down onto the deck!"

  "Yes!" Freddy Farmer said in a tight voice. "A little Jap friend ofours. Who else could it have been? It couldn't have been anybody else,Dave. The dirty blighter. He probably didn't trouble to use his gun.Didn't even have to get close to us ... But, good gosh, Dave! How inthe world did he get the chance to do it? How did he know when heshadowed us up to Los Angeles that we were going to take the very firstplane off, and that we'd carry the mail?"

  "I don't know," Dawson mumbled, and rubbed some of the tannic jelly onhis smarting hands. "It's like one of those impossible cockeyed thingsyou read in dime thrillers. Maybe he didn't do it, himself. Maybe he haspals at the L.A. Base. He certainly had one at Dago. Maybe he didn'teven show his face to anybody, except a pal or two of his. And maybewe're just kidding ourselves. Maybe he didn't have a thing to do withit. Maybe it was just plain sabotage by some other rats he never evenmet. I--gosh! I'm almost beginning to feel sorry that you belted thatsubmarine down to the bottom, Freddy. Believe it or not, those rats,while trying to knock us down with their little trick, actually savedour lives."

  "What's that?" Freddy asked sharply. "Dirty Japs save anybody's life?Not a bit, they would!"

  "Not knowingly, no," Dawson said, and absently checked the course of theFortress that was still droning along on the automatic pilot. "But thosesubmarine birds did, just the same. Supposing that sub hadn't showed atall? Supposing you hadn't gone back to work the guns, and looked intothe bomb-bay? We would suddenly have found ourselves sitting on thefront end of a flying ball of fire. See what I mean?"

  "Too vividly!" young Farmer said with a violent shudder. "Why, theblasted fire might even have reached the gas tanks before we could havebailed out. Gosh! maybe I am a little sorry that I sent the lot of themto the bottom."

  "Well, don't be too sorry," Dawson said grimly. "They're still Japs. Andthere's still a lot of their cutthroat brothers on the face of the earththat need the same kind of treatment."

  "And will get it, too, if I have anything to do with it!" Freddy Farmerechoed, tight-lipped.