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Journalist:June Callwood:The Day the Iroquois Flew

The Day the Iroquois Flew


Originally published February 1, 1958. This is the story of the first flight test of the Iroquois engine, on it's B-47 flying testbed.
Republished with permission; June Callwood and thanks to Macleans Magazine.
Perhaps it was already obsolete. But to those who built it and to those who risked their loves to test-fly it, the first flight of the world's most powerful jet engine was the tense climax to four years of dreams and drama.
HOW IT FLEW: Fastened to the tail of a B-47 bomber, the Iroquois engine is test-flown near Toronto. Some experts believe, full out, its scream could kill.
By June Callwood

        The big plane hung low under listless cloud, a freak aircraft that induced pity for its awkwardness. Basically it was still a medium bomber, the B-47, with six jet engines streaming black smoke, but aeronautical engineers had warped its shark outline. Clamped to one side of its tail was a seventh engine, the two-ton Iroquois, which has been called the most powerful jet engine in the world. Canadian-designed and built, its four year development program had cost at least thirty million dollars. On November 13 around noon on a day that threatened rain, the Iroquois was lugged into the sky for the first time by the B-47 and started. Some felt that the resultant roar was only simulated life; with Sputniks racing overhead it may yet be decided that the Iroquois was born dead.
       In spite of the sense of doom that rolled around the horizon, few mechanical births have been so joyously received. The Iroquois is being built by Orenda Engines Limited, a subsidiary of A. V. Roe Canada Ltd., at Malton, near Toronto, and the company was anxious to see the engine airborne in order to soothe government sponsors grown restive. The company had taken only three years to put into production its first jet engine, called the Orenda, now flying in Sabres and CF100s on four continents. The Iroquois flight tests, however, had been notably laced with delays. For almost a year before it was actually airborne the company periodically predicted that the engine would fly "in a few weeks."
      While the company took four years to bring the Iroquois from the drawing board to the moment of flight, its officials say the performance was far from slow, considering the difficulties. Had it followed the general practice of aircraft engine companies the next engine built after the Orenda would have been only slightly more powerful. It was decided in 1953 to leap-frog this logical step, and the next, and build the strongest engine in the world. The company was then just seven years old; some felt the project was brave impudence.
      The hitches were just as massive as the dream. Orenda needed a huge airplane to support its baby brute through flying tests. Several were considered and the B-47, ninety-ton jet successor of the "Flying Fortress;" was determined to be best. Torrential paper work ensued but eventually the United Stales Air Force "lent" a B-47 to the Royal Canadian Air Force, which "lent" it to Orenda. Canadair, an aircraft company near 'Montreal, needed more than a year to fit the plane with the lopsided pod that houses the engine and equip it with almost twenty tons of ballast and instrumentation.
     The engine itself contains a great deal of a new metal called titanium, as strong as steel with little more than half its weight. Orenda had to pioneer in the use of titanium, a metal so tricky that it had to be welded in a bubble chamber from which all oxygen has been removed. The inventors discovered, when they placed their twenty-foot offspring on a test bed for the first time that they had created simultaneously the worlds most powerful engine and one of the worlds loudest noises. When the Iroquois is running full throttle its noise is sufficient to deafen a man permanently; in fact, some even believe it is possible the noise will kill a man standing a hundred feet away. New test cells, two-story vaults where the engines can be mounted on concrete blocks and run for days in order to test component parts, had to be built with extraordinary sound-swallowing capabilities that cost about eight million dollars. The problem of protecting the hearing of ground crews is a matter of continuing research and will still be under study and refinement when the Iroquois is finally wedded to Canada's fighter, the Arrow.
     As the summer of 1957 turned languidly into late-arriving fall, the time was reached when the Iroquois had to be flown. The government was impatient, critics had a satisfyingly large target for harpoons, one of the payments on the RCAF contract was hanging on the event. The company itself was suffering from a mass case of nerves. Tempers were waspish and irritation became almost constant.
     Discussing the possibility of a titanium fire in the engine, which can only be extinguished by smothering, an engineer one day asked one of the test pilots what procedure he was considering.
     "Well," the pilot began lazily, "first I'd jump out...."
     "THAT'S NOT FUNNY!" shouted the engineer, furiously.
      On the morning of the flight the B-47 was parked in a corner of Malton Airport, where airline captains, to the despair of the control tower, veered from normal taxiing areas to trundle passengers past for a closer look. The B-47 seemed dispirited. Its flexible wings, which can flap as much as seventeen feet in storm flight, drooped. Its bands of fluorescent red paint, required by experimental aircraft as a warning to curious sky sightseers, had peeled and blistered. The USAF markings had been removed but the ghosts of the letters showed through. The former bomber hadn't left the ground for five months and to the casual observer had acquired a rooted look, as though geraniums might soon be planted around the undercarriage and washing strung from the two-story-high tail fin.

      A small knot of men was gathered around its tail, huddled in turned-up coat collars and peering with cautious faces into the blackened tailpipe of the Iroquois. The inert metal slug of an engine, which one day may have an estimated hundred-thousand-dollar price tag, gave back no hint of its present mood.
With co-pilot Len Hobbs peering over their shoulders, ground crewman make a final inspection of the Iroquois. The engine, which may sell at over a hundred thousand dollars, will power Canada's new fighter-interceptor, the Arrow.

      The two pilots, in dull-blue flying suits, stood aside, glowering indiscriminately at the thing they were asked to fly, at representatives of a management that required them to fly it and at the weather, which threatened to impede a flight they didn't want to postpone again. They were no longer discussing the issue of two days ago, when they had first expected to test the engine. A snag had been discovered in the Iroquois. with one and possibly two oil leaks. The inspection crew, in spite of awareness of high-level urgency, had refused to certify it ready for flight.       Nevertheless, a compromise was reached. Changing engines with one of the others available might have meant a month's delay, so it was decided to test the engine anyway, but only at idling speed.
      The inspection crew then described the plane suitable for flight "under limited conditions" and the pilots agreed. It wasn't the happiest arrangement, but it would have to do.
      Now, with apprehension pitched so high it was inaudible, clouds rolled over the airfield and rain was forecast. No test flight can be carried out until visibility is better than three miles. A light going out at Malton's control tower would give the signal when conditions cleared. The flying crew, two pilots and a flight engineer. watched the weak sun working through the murk and waited. To avoid the subject at hand, they talked about Wichita, Kansas.
      This crew, Michael Cooper-Slipper, chief test pilot, Leonard Hobbs, the other test pilot, and John McLachlan, flight engineer, had been the first civilians from an outside country to train on the USAF's B-47. Exactly a year before, they had spent six weeks at the Strategic Air Command's training base, McConnell, outside Wichita. Skipping only the lectures on bomb-aiming and nuclear devices, they took the stiff SAC training that begins with 6-a.m. briefings.
      They discovered what they had gloomily suspected, since they have long maintained that modern pilots are no longer fliers, but airplane drivers. The B-47, more so than any of the fifty planes Cooper-Slipper and Hobbs have flown, is operated mathematically. Pilots carry a briefcase into their cockpits and require a slide rule.
     "The B-47," their instructor told them, "is critical on fuel. In fact, the B-47 is critical all around."
       It is the fuel problem that makes the slide rule necessary. The basic weight of the B-47 is about forty tons and it can take on up to fifty tons more of bombs and fuel. Its varying weight, however, determines its lake-off speed and its landing speed. Pilots must know, to the pound, how much the plane weighs.
      "I've got a very funny idea," Hobbs murmured dreamily one day. "I think I'll take an abacus into the cockpit. Can't you see the instructor's face?"
       The calculations in the cockpit are continuous. For example, the B-47 uses two pounds extra fuel per degree of a turn sharper than thirty degrees. Nothing is casual---"The B-47 is a very unforgiving aircraft," someone commented--- and each man sits at the centre of more than a hundred dials and instruments. "Remembering that there is fuel all around you, in the body, even under your seat, helps to keep your mind on your work," observes Hobbs.
       The two pilots became celebrated members of the officers' club at the Kansas base "Do you mean," asked a Texan incredulously "that you little old Canadians have got the biggest engine in the world? And you're going to put it in the tail of a B-47? Man, you're crazier than we are."
       Strategic Air Command stopped buying B-47's in 1956 and switched to the longer-range eight engine B-52s. By that time SAC had about three thousand B-47's scattered all over the world. Every one of them could carry a single bomb that had more explosive power than all the bombs dropped by all the combatants in World War II, SAC made certain that this information was general knowledge. Of its insignia, a mailed glove holding lightning and an olive branch, its former chief once said. "You takes your pick."
      The USAF pilots training at Wichita were under a strain, not only because they were aware they might be required to push a bomb-release button some day, but because the course was ruthlessly tough and many of the students were high ranking officers past youth who had known their own commands. Much dignity was lost. "I saw a major with eighteen years of flying experience being chewed out by a kid," Cooper-Slipper reported one morning. Hobbs pointed, "Look over there, a full colonel is getting it."
      The refuge was humor in the cocktail lounge environment of the officers' club. They swapped shop talk. Korean veterans spoke of jet-fighter dogfights with the Russian MIGs, considered by most pilots to be the last dogfights war will know because modern fighters are so fast no flier will see his enemy. They discovered that Cooper-Slipper, thirty-seven, a mild green-eyed man, had fought Germans in Battle of Britain, in which he won a Distinguished Flying Cross, and Japanese over Singapore, where he was briefly captured in a jungle and escaped by Chinese river boat to India.
      Cooper-Slipper, now a Canadian citizen, received his DFC for ramming a German bomber. The impact sent both planes screaming down in flames and Cooper-Slipper recovered consciousness hanging from his parachute with some of his fingernails ripped away.

      "Why did you ram it?" someone asked.
      "I was out of ammunition."
      "I said, why did you ram it"
       Cooper-Slipper considered. "Everyone to doing that sort of thing at the time. It seemed, well, stylish."
      "C'est la cotton-pickin' guerre," nodded a southerner. "I remember one time I was taking off and I looked below and saw this buddy who was right behind me go crashing into the end of the runway. The student says to me, 'What'll I do?' and I said, 'Be quiet, I'm thinking.' "
       There was an uproarious laugh in which the pilots' wives shared only thinly. "Well, there were flames everywhere so I figured he had bought the farm. A few days later I saw him again. 'Not you!' I said. 'Sure,' he says. 'That fighter isn't much of an aircraft, but they sure build the cockpit strong!' " The men around table laughed again, but the women were quiet.
       The B-47 bred its own jokes. " If an engine starts to burn," an instructor said one day, "let it burn. No sweat. You've got five more."
       Noticing trouble with an engine during a flight, another instructor ordered his student, "Shut down Four!" "Sure," replied the student cheerfully. "Which four?"
Flight engineer was John McLachlan, Idling the jet uses 600 gallons an hour.

       No sweat," recalled Hobbs lightly, as he surveyed the B-47 waiting for him at Malton a year later. "If we lose an engine Mike, we've got six more." Cooper-Slipper smiled without mirth and Hobbs squinted in the direction of the control tower. Hobbs, thirty-seven, is father of four small girls. English-born, he spent most of the war impatiently instructing in Canada and later saw action over Sumatra and Malaya. He looked away from the tower and looked back again hastily, "Mike, there's the light! We can go!"
      ''Where there had been apathy, there now was hustling, ordered confusion. Ground crews pulled the covers off the six slender engines and engineers stepped away from the humping bulk of the Iroquois. McLachlan, the Scottish-born flight engineer, climbed the ladder into the plane first, edging along the narrow aisle to the nose of the B-47, where he sat almost in darkness, except for three small almost above him."The mole hole," crews call the engineers cockpit. He checked over the extra instruments that would give him readings on the behavior of the Iroquois.Many of the readings would be done automatically, recorded on film and tape. Central Records Room, near the ponderous earthound test cells, would also be receiving information, which could be fed into an electronic computer, assayed and typed into a full report before the aircraft landed. Aero-dynamicists have developed a cavalier attitude toward the importance of human judgment. "The pilot is still useful," one of Orenda's engineers explained benignly. "For example our instruments don't tell us if the engine gets wet. A pilot can report back if it is raining."
       The pilots, at this point, were climbing ito the B-47. The pre-flight check of two hundred bits of equipment and instruments, which takes better than two hours, had been completed long before but some final calculations and checks had to be made. They fastened their parachute harnesses, cramped in the confines of a cockpit so narrow that they sit one behind the other. They plugged in the cord for the wireless, settling gold plastic helmets on their heads. The earphones are in the helmet and the speaker in the mouthpiece of the oxygen mask. They connected their oxygen outlets but let the rubber smelling masks hang free.
      Cooper-Slipper was rechecking his fuel. He had started with thirty-six thousand pounds of good-grade kerosene, which jet engines burn. Pounds are used as a fuel measure, rather than gallons, because they are more reliable. A gallon of kerosene weighs about seven and a half pounds.
      The Iroquois engine had been run two days before for a few minutes to determine whether the oil leak was still present-it was-and in the process about four hundred pounds of fuel were used. It would take twenty-five hundred pounds of fuel to start the six regular B-47 engines and taxi the aircraft to the runway, and another six hundred pounds to get the plane into the air. The Iroquois at idling speed would need about forty-five hundred pounds of fuel an hour, better than six hundred gallons. Take-off speed, Cooper-Slipper computed, would be a hundred and thirty-three knots. The plane began to move.
      "Do you smell fuel?" Cooper-Slipper asked Hobbs over the intercom. Hobbs sniffed the fumes of kerosene seeping into the cockpits, made a decision that it was unimportant and said firmly, "No."
      "We're off then," said Cooper-Slipper. Lumbering with a sense of protest, the heavy plane lurched along the runway, pivoted clumsily and paused, waiting for clearance from the tower to take off. The six engines fouled the air behind with towering black smoke. Charles Grinyer, engineering vice-president of Orenda who all but broke his health on the Iroquois project, was startled the first time he saw the B-47 rolling by. For a moment he thought it was on fire. Its capacity to create more smoke than a coal-run locomotive is not considered the B-47's proudest achievement.

Burt Avery, at thirty-five a deputy chief engineer and one of Iroquois' principal designers, stepped out of his office to watch the B-47. Designing jet engines is a young industry, only fourteen years old, so Avery's youth is not considered extraordinary at Orenda. With Harry Keast, the chief engineer he had been present at the moment the Iroquois ran for the first time in a test cell and both men considered this the most exultant few minutes of the entire project.
       When the first engine was put into a test cell several years ago Charles Grinyer was there along with Keast and the voluble, intense Polish-born Alex Muraszew, now a deputy chief engineer. They worked through the day preparing for the first start, stayed in the factory into the night. Around two or three in the morning they started the starting motor to spin the Iroquois' compression blades. The Iroquois ran, with flames pouring through its turbine, but quit when the starter motor quit. The men went home too defeated to speak much and returned the next day.
       Grinyer had to catch a plane to Ottawa. He waited as long as he could and then, throwing a few agonized suggestions over his shoulder, hurriedly left for the airport. A few minutes later the Iroquois ran by itself, without the support of the starting motor, and sucked a snowstorm of insulation material out of the walls of the cell. The engineers hugged one another and got the message to Grinyer just before he climbed in his plane. He reported later he grinned all the way to Ottawa.
Tense and weary, Burt Avery waits it out.

     "That was the best moment, the first time it goes." recalls Keast. "The best moment."
Avery agreed, but on the momentous day of the flight test he watched the B-47 just the same. Earlier in the test program, an Iroquois had partially exploded in a test cell, spraying shrapnel-like pieces of metal all over the room, which providentially now is sheathed in shrapnel. This had happened more than once during tests and, in a sense, was to be expected. He was as certain as an engineer can be that the Iroquois in the B-47 would not explode, but he nevertheless was uneasy.

Copyright June Callwood ©

FYI: This engine is on display at the Canadian Warplane Heritage Museum

Scott McArthur.




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