As Stan worked on the supercharger he went over his plans carefully. With everything about ready to make tests, he was beginning to wonder if the story Swen had told him was not just the wild fancy of a scared kid. He even thought of the possibility that Swen had been planted to get him off on the wrong track. There had been so many crazy things happening that he could not afford to overlook any angle.

He had three mechanics helping him, with Hans giving his orders to the two who spoke no English. As he worked he began to wonder if he had not been neatly tricked. He was sure that at least one of the men hanging around watching him was a Luftwaffe pilot. No one interfered with his work or tried to tell him what to do. He was having as free a hand as though he had been working in a shop of the Eighth Air Force. Some of the men scowled at him, but most of them just watched with interest and with something else. Stan guessed they were eagerly waiting for the trap to spring. Then they could have a big laugh on the dumb Yank.

The supercharger parts were about installed in the ship. Stan checked the gasoline supply. There was just enough to fly him out over the channel if he took off before he used too much. Once out over the channel he might be able to water-crash the P-51 near a British patrol or pick-up boat. The trouble was that the instant the engine began to work the trap would be sprung on him. He had to figure that one out fast.

Swen showed up and hung around watching along with the other mechanics. He grinned at Stan once and shook his head. Stan winked at him. Herr Domber showed up in a sports outfit. His white spats gleamed and his yellow tie shone. Domber was in a very genial mood.

"You are progressing?" he asked.

"I'm getting the thing together, but I don't know whether it will work," Stan said.

"We will have lunch at a cafÉ downtown today," Herr Domber said without the flicker of an eye. "I have a special cafÉ in mind where the sea food is excellent and the wine very choice."

"That will be fine," Stan said and grinned as he hoisted himself up into the ship.

He lay inside the fuselage and looked at the supercharger. There was one valve which he had not fitted. He was afraid that if he fitted that valve into place the Mustang would purr like a cat. He was now convinced that the Germans had had all of their trouble with the air mixture and the pressure intake. His instructions on the new machine had been very detailed on these points. They were the secrets of the new supercharger.

Stan plugged the valve opening with a wad of cotton waste and tucked the valve into his pocket. Of one thing he was sure, the Mustang's engine had to be hot if he expected to snap her out of that hangar. And in getting her hot he did not dare let her show signs of running smoothly. Climbing out of the fuselage, he called to Hans:

"We'll turn her up." He wiped sweat from his forehead. The air in the hangar was hot, kept that way to make engine starting easy.

Hans and his men wound up the Mustang. Stan climbed into the cockpit and got set. From where he sat he could see, through a plate he had removed from the panel, the adjustment valve he had seated with waste. He could reach it by bending over.

The Mustang's engine turned over and she sputtered once or twice but refused to start. The wad of waste was no good. He had to seat the valve. Looking out he shook his head to Hans. Then he noticed that Domber was talking to an artillery captain over by the gate. He was shaking his head and making violent gestures.

Stan watched him carefully. It might be that Domber was telling the gun captain not to blast the P-51 if it made a run. In that case Domber had plans even if Stan got the ship away. Domber came back to the P-51 and Stan looked the other way as he bent forward and seated the valve.

The tough part was that if he hit the mixture just right in seating that valve the engine would hit it off at once. Stan knew how those Allisons worked. Given a hot room they might flip right over and go off with a bang. He climbed out of the cockpit and made a few last checks on the outside.

A water boy came up and the men crowded around for drinks. Stan watched the water boy carefully. He was again thinking about the poison business. The water was in a pail and the men were dipping it out in a tin cup. That did not look dangerous and Stan was very thirsty. He turned his back and climbed into the cockpit again. He was down inside, working on a repaired cable. Close to his face was the hole where the shell had ripped through and severed the cable.

Suddenly Stan heard someone whispering. It was the voice of Herr Domber.

"Get set, fool, and when the boy offers him a drink you are to shake your head. In that way he will think he has escaped being poisoned. He is just stalling now. I want this ship tuned up. If you fail, it is the Russian front for you."

"Yes, sir. Heil Hitler," Swen's voice answered.

Stan grinned broadly. He finished with the cable. One thing was sure. The poison story had been a gag to make him think he had outwitted Domber. He climbed out of the cockpit and walked over to Hans.

"We'll hit her again," he said.

Turning back he noted that several of the mechanics had moved in close. A quick glance showed bulges under their coveralls which looked a lot like army pistols or automatics. The water boy moved toward Stan. Looking past the boy Stan saw Swen. Swen began shaking his head as Stan looked at the water pail. Stan pretended not to see him, though Swen was squarely in front of him.

Reaching down he took the tin cup, filled it, and drank deeply. He had a second drink, then tossed the cup to the boy. As he did so, he shot a side glance at Herr Domber and almost burst out laughing. Domber's face was red and his mouth was screwed into a snarl. Suddenly Stan felt sorry for Swen. He nodded to Hans as he climbed up.

Looking down he saw the mechanics with their bulging coveralls crowding in close. Several of them had ripped their suits open and had their hands inside. Stan eased back against the shock pad. The left brake was the one to kick down hard. He had shoved the chock out from under the right wheel. He had a momentary feeling that the builders of the Mustang should have extended the armor plate further forward. The men on the ground would have a clean shot at him. They were well forward now and watching him like cats at a rat hole.

Hans kicked the engine over to prime her. Stan got set and eased on the switch. She turned over slowly, fired twice, idled, then fired again. Sweat broke out over Stan's forehead. Below him the faces of Domber and his men blurred. The engine kept on rumbling and sputtering. Stan relaxed as he pretended to be working on the gas adjustment.

He gave the valve a turn and the Allison smoothed considerably. Leaving it that way he looked down at Hans, a deep frown on his face. He shook his head and motioned to the mechanic. Hans did not know what he wanted, but he moved around to the side of the ship. Stan was sorry to have to use Hans as a shield but he knew, now, that a quarter turn more on the valve would set the Allison roaring. What he needed was a bit more heat on his temperature gauge, and he wanted to keep Hans in line.

Bending over he bellowed at Hans, making his words jumble together. Hans looked blank and shook his head. Stan scowled at him. Then he got a bright idea. He looked over at Domber and beckoned to him. Domber came over. He was shorter than Hans. Stan reached down and bellowed:

"Get up and I'll show you how to adjust this type of supercharger!"

He even gave Herr Domber a hand up on the step. Domber leaned into the cockpit. Stan pointed to the valve. His fingers closed over it and began to turn it. Then his right arm shot out. His fingers gripped Domber's yellow tie. The Dutch Quisling's eyes bulged and he pulled back.

In that instant the Allison surged into full, smooth power. Stan kicked down on one brake and snapped her around. Like a falcon launching out from a limb, the Mustang shot toward the opening ahead. Stan held Domber over the edge of the open hatch until the ship was out in the sunshine, then he gave the little Quisling a shove.

Hoiking the tail of the Mustang, he hopped her suddenly. It was a trick he had depended upon to save him from the guns. As she shot upward he saw flame and fire rip the runway. The blast was so close to his belly that it sheared away most of the landing gear. Stan banked and dropped back down toward the roofs of the city. As he laid over he saw the withering fire on the runway lift. Amid the ripped up slabs of cement he saw a man lying sprawled on his face. He was half covered by a slab of concrete.

"One for the Dutch patriots," Stan said grimly.

As he roared over the rooftops, Stan leaned back and laughed. He would have to fly low because the high-level dual supercharger was not working. All he had done was adjust the regular carburization system. He had not taken chances on his work on the high-altitude machinery.

There were no Nazi planes in the air. There had been no alert. Stan was sure there would be no attack until he reached Rotterdam. Using the tactics of the Rhubarb Raiders he flew low over the tile roofs and the windmills.

In a surprisingly short time, the Mustang broke out over Rotterdam and Stan straightened his course. His compass was out, the gyro-horizon had been removed and both clocks were stopped. The radio had been stripped out of the ship along with every other instrument not absolutely necessary to test flight. Domber had only wanted to learn about the supercharger. His egotism in believing everyone else was dull-witted compared to himself had saved Stan.

Over the estuary of the Rhine River Stan met his first flak. A startled battery opened up as he flipped over so low down he could see the buttons on the artillery men's uniforms. The firing was wild, but it roused gunners out on the Hook of Holland. There the Jerries did some closer shooting. But Stan was dusting the concrete emplacements and the gunners did not get their hearts into the job. Stan flipped up over blue water with a grin on his face.

Checking his gasoline supply, he judged he could get to the middle of the channel. He had no parachute and no life belt or Mae West suit to float him. The chill water of the channel would soon drag him down. He had to locate a patrol boat or a British ship of some other class. And he had to watch for Messerschmitts and Focke-Wulf fighters.

High above him he spotted three fighter craft. He saw them wheel and bank into the sun. They would be coming downstairs to have a look. Possibly they had been warned by radio to look for him. A minute later he spotted five more planes and these he was able to check. They were FW 190 fighters and they were coming up from the direction of Ostende on the Belgium coast. Then he saw two Me 109 Stingers slipping in from the other side. Stan kicked the Mustang wide open. No use trying to save gas by holding cruising speed. He had to get away from that coast.

The Mustang knifed ahead and Stan bent forward as the air-speed indicator rolled up to just under four hundred miles per hour. There was no more boost and he longed for the dual supercharger. The FW's dropped in behind, unable to head him off, but the Me's came on like falcons trapping a homing pigeon. Stan felt a good deal like a pigeon. He was unarmed and he was carrying a vital message that had to get through. He dived down close to the water and roared ahead.

One Me dived in on him and zoomed over him. Stan felt lead spattering all over his ship and saw cannon shells hit the sea close below his wings. The second Me came in and Stan slipped a bit, kicking the top of a wave with his port wing.

The Jerry was coming down at a terrific rate. He did not think any sane flier would be zooming along on the crests of the waves. When Stan dipped, the Jerry missed him and shot past. Stan pulled up sharply just as a great cloud of water and smoke lifted above the sea. The Jerry had hit nose-on. Stan saw the tail of his ship and one square-tipped wing rise above the green water, then slip from sight.

In coming up Stan went over the third Me. It managed to flatten out but went skidding along the tops of the waves for a half mile before it got into the air again.

That gave Stan his chance to get away. He could outrun the Me's once he got them down on his level, where they could not use their diving speed. But the three fighter craft he had first spotted were coming down now. They were dangerous ships. All three of them were FW 190's, and diving on an enemy from above is a job the FW does best.

Stan settled down close to the channel again and kept racing on. The FW's were sloping in at a screaming pace. Stan felt their first lead as it hailed around him. He stayed in the fire a split second, then bounced up and over. He saw the three FW's far below him. They were coming around for another climb.

"Sorry, fellows, but I just can't wait," Stan muttered.

He nosed down again and used the slope to build up speed. Suddenly he glanced at his gasoline indicator. It was getting wobbly. Stan went up again to have a look around. Far ahead he spotted two black specks with smoke pluming up over them. That meant larger ships than patrol boats. They might be German light destroyers on patrol, but they were the only craft in sight. He had to make a try for them.

Sloping off again, he roared away toward the ships. Slowly their hulls became larger and Stan saw that they were destroyers, small, sleek, and fast. They were plowing along at top speed, which was not a good sign. German craft in those waters would be making knots because Allied planes kept a sharp watch over the channel.

Stan went in at top speed. He was still a long way from the two ships when his engine quit. It went out without any sputtering at all, and it refused to rev up a single blast.

Flying so low, Stan knew he would not stay up over any great distance. He felt the Mustang begin to settle. The ships were closer now, but he still had not identified them. That no longer mattered. If they were German he would just sink with the Mustang. Considerable haze and smoke enveloped the ships. They were putting about and swinging away from him so that the smoke kept them covered. Stan had a wild notion they thought he was trying to torpedo them and were taking evasive measures.

"Germans," he said between his gritted teeth.

Then the Mustang shot through the smoke, grazed the prow of one of the destroyers, and settled into the channel with a terrific splash. Stan heard anti-aircraft guns blasting away and saw flame and smoke belching from dozens of gun muzzles above him. "They aim to finish me off right," he thought wryly.

He promptly forgot his resolve to go down with the Mustang. Pawing the hatch cover open he heaved himself out of the cockpit and tumbled into the water. A big wave rolled over him and the suction from the sinking Mustang dragged him down. Savagely he battled his way to the surface. He was pawing and sputtering but able to swim strongly.

Looking up he saw that he was close beside the destroyer or her sister ship, he did not know which. Something white came sailing down toward him and he heard a voice shout to him:

"Blimey, old man! Grab the preserver!"

Then Stan saw that two other life preservers had been tossed to him. He swam to the nearest one and grabbed it. He was shaking from the cold water but he laughed. The destroyer was flying the ensign of His Majesty's Royal Navy.

A few minutes later a boat picked him up and he was rowed to the destroyer. Climbing aboard he was met by the commander. Stan saluted the officer.

"Lieutenant Stan Wilson, Eighth Air Force, reporting, sir," he said.

The commander looked at Stan's clothes, then smiled. "Where were you going with that Mustang, Lieutenant?" he asked.

"I was headed for home, sir. You mistook me for a Jerry and started shooting."

"No, we knew what you were. We just bagged two Focke-Wulf fighters off your tail. But you can report in detail after we get you into some dry clothing."

Stan followed the commander to the officer's quarters. After climbing into a navy blanket and swallowing hot tea, Stan told the commander his story. He did not keep anything back. When he had finished, the commander said:

"We could radio in a warning, but I think High Command might appreciate it if we took no chances. We'll put in and rush you right to Eighth Air Force headquarters. That way the Germans won't be able to learn anything."

"The FW that got away will report I was blasted into the sea. Anyway, I have a personal score to settle with a Nazi who is passing himself off as a pal of mine."

"Better get in touch with the big boys first," the commander advised.

"I'll take care of both jobs," Stan promised.