Reflections from the Dome

Fokker F-10A Super Trimotor NC999E

Fokker F-10A Super Trimotor NC999E

For more information on Rockne's fatal last flight, take the link below to a chapter entitled "The Flight of NC-999" from Jerry Brondfield's book Rockne: The Man, The Myth, The Legend. http://www.irishlegends.com/pages/reflections/reflections5.html

The following article is The Legacy of the Rockne Crash by Herbert M. Friedman and Ada Kera Friedman and is from the May 2001 issue of the British Aeroplane Magazine.

(Article provided by the University of Notre Dame Archives)

March 31 (2001) marked the 70th anniversary of the crash of Fokker F-10A Super Trimotor NC999E at Bazaar, Kansas, which took the life of famous American football coach Knute Rockne. The aircraft's fatal plunge from low altitude, followed by its severed wing, dramatically affected the development of air transport worldwide.

Trans Continental and Western Air (TWA) Flight 5 to Los Angeles via Wichita, Amarillo, Albuquerque and Winslow departed Kansas City at 9:15 am on March 31, 1931, on its scheduled I hr 10 minute flight to Wichita, Kansas, 180 miles away. Among the six passengers was Knute Rockne, coach of the "Fighting Irish" American football team of the University of Notre Dame. Aged 43, Rockne, with his never-to-be-equalled record of five udefeated seasons and 105 wins to 12 losses and five ties; was indisputably the greatest American football coach of all time. He was also a noted promoter of aviation, and had chosen TWA to get him to Hollywood to clinch a rumored $50,000 offer to advise or appear in a Universal Pictures football film.

Rockne once said: "With a good pilot and a good plane, [flying is] as safe as any other method", and on this, its five-month-old blue ribbon 36hr transcontinental service. TWA gave him the best of both. The captain (then called "first pilot"), 32-year-oId Robert Fry, had accumulated much more flight time and experience than the minimum 2,000hr and five years TWA required for his $500-a-month job.

The aeroplane was the best in TWA's stable. Twelve-passenger Fokker F-10A "Super Trimotor" NC999E was an American licence-built development of the ubiquitous Fokker F VIIb-3m. Although it was faster and, at 14,000Ib gross weight, heavier, this high-wing monoplane closely resembled the Fokker-licenced Avro Type 618 Ten. It cruised at 123 m.p.h. on the power of three 450 h.p. Pratt & Whitney Wasps, and featured the all-wood, multicellular cantilever wing that Anthony Fokker and his engineer, Rheinhold Platz, had developed with such success for their First World War fighters.

The weather was inauspicious. So much so that Anthony Fokker would later angrily argue that the flight should never have gone ahead. A cold drizzle mixed with snow fell from a lowering sky at Kansas City. Wichita, the destination airport, reported sunny conditions, but that contrast was less a comfort than a warning. The temperature at Dodge City was down to 6F. Just 100 miles eastward they ranged above 20 and more; 32 at Kansas City. To reach Wichita, Flight 5 was going to have to penetrate a sharp cold front. Where the cold air from the west met the warm moist air mass further east there were sure to be clouds, fog, ice, and ceilings within 200ft of the ground.

As there were no survivors, subsequent events can be gleaned only by interpreting the available small bits of hard evidence with an unavoidable amount of speculation. The first few minutes of the flight were probably pleasant, at least for the passengers, combining the still wonderful excitement of flying with the uncovenanted thrill of sharing the cabin with a national celebrity. But within the first hour of the flight NC999E encountered the old front and things began to come unstuck.

Paul Johnson, an airmail pilot who left Kansas City for Wichita 15min after the F-10A, in a faster machine, passed Flight 5 over Emporia, about 100 miles from Kansas City. He later reported fog, clouds and icing that forced him to fly close to the ground. At 10:22 am, 1 hr 7min into the flight, Fry's copilot, Jesse Mathias, radioed the TWA station at Wichita, reporting their position as N35 miles from Cassoday." When TWA operator G.A. O'Reilly told him that Wichita weather was clear, Mathias said: "The weather here is getting tough. We're going to turn around and go back to Kansas City."

According to some accounts the next exchange was at 10:35 am, when, on being told that Wichita was stilI clear, Mathias said that they would try again to reach their original destination. At about the same time Robert Blackburn, feeding cattle near Bazaar, heard an aeroplane heading toward Wichita. Where was Flight 5? How high was it? How were the crew navigating?

The local newspaper was puzzled by the crash location. "The plane when it crashed on the Baker ranch [near Bazaar] was many miles to the west of its course, as the regular route which is marked by beacon lights would have taken the plane in a direct course, ...over the beacon light on the Wagner farm...then to Cassoday." The diversion was attributed to an attempt to penetrate the front, but the authors believe there is a better explanation. Beacons would have been invisible in the drizzly daylight, and there was no hint of radio navigation being used on the flight. There was, however, one navigational aid in place. Installed at a cost of millions and requiring tens of thousands annually to maintain, it was available to Fry without charge. It was ever-present, unfailing and its use by the pilot required no on-board device. It was the "Old Iron Compass".  Railways were ideal guides. Their designers' imperative to minimise gradients put the right of way along the lowest possible route, with no ascents exceeding an aeroplane's maximum rate of climb. Robert Serling, TWA's chronicler, quotes a pilot of the era: "You'd find a track and switch on your landing lights. You'd fly as low as one hundred feet and even in heavy snow the tracks would shine like ribbons of steel. We'd follow them for miles and miles."

The Atchison, Topeka and Santa Fe Railway connecting Kansas City with Wichita runs well west of the direct route but within a mile of the crash site at Bazaar. It is a good bet that when Jesse Mathias told operator O'Reilly that he was "Too busy" to talk, they were headed back toward Kansas City with both pilots squinting through rain-streaked windshields, trying to stay out of the clouds while following the sweeping rails only 200 or 300ft below.

"Scud-running" is stimulating flying. With rising terrain and a lowering overcast it becomes downright interesting. Errant wisps of cloud would have blocked their vision, first occasionally, then more often. There would be breathless moments when the rails seemed Iost for good. The only remedy was forward pressure on the control column and a loss of 25 or 50 ft. The right of way would reappear clearly for a while, but then the process would begin again. A deadly situation was developing. Now the rails were snaking through the Flint Hills; no longer the flat, featureless Kansas of Dorothy, Toto and the Wizard of Oz. The clouds were almost touching the hilltops. Once the crests disappeared the Fokker would be trapped and the option of climbing to at least temporary safety forfeited, since to do so would involve a good probability of crashing into the hidden high ground. They were being squeezed between the ground and the overcast.

At 10:45 am Mathias again called O'Reilly. It was less than 5 minutes before impact, as established by the stoppage of the passengers' watches and the cockpit clock. "We're headed back but it's getting tighter. Think we'll come on to Wichita, It looks pretty bad." Proximity to the ground; the clouds and the hills would have made a simple 180 turn too dangerous. We believe that Fry now firewalled the throttles, raised the aircraft's nose and climbed into the overcast.

Once in the clouds they were dependent on the Fokker's instruments; its tachometers, magnetic compass, airspeed indicator and the all-important gyroscopic turn-and-bank indicator. Although it would be two years before any American governmental requirement was established for instrument proficiency, even for airline captains, these would have been sufficient to keep the wings level and to control the airspeed under ordinary circumstances. But circumstances were not normal that morning, and this is probably the key to NC999E's last minutes.

Fokker F-10 cockpit

Fokker F-10 cockpit

First of all, lateral stability had been compromised. Apparently, on the advice of a manufacturer's representative, both ailerons* had been readjusted to ride an inch above the wing's trailing edge. The aeroplane would now bank on small control-wheel inputs, but would require unusually heavy control to recover, placing a premium on keeping the wings level by reference to the turn-and-bank indicator. Unknown to the pilots, that instrument was dying.

*ailerons: A small hinged portion of an airplane's wing, used to make an airplane roll, or turn around its long axis.

Conditions over Bazaar were ideal for the formation of ice, as evidenced by the small U-shaped pieces found at the crash site. In seconds ice would have formed in the exterior venturi (pipe) that, we believe, powered the gyroscope. Deprived of suction, the instrument would spool down until its springs held the needle vertical regardless of the turn. The next instrument to go would be the airspeed indicator, as ice choked the pitot tube and covered the static ports.

Deprived of these key referencences, the disoriented pilots would have been unable to keep the airliner from entering a spiral dive. The Fokker was now out of control, nose down and accelerating. When screaming engines and runaway tachometer readings alerted the pilots to their predicament, Fry, in a futile effort to slow the machine, would have pulled the throttles right back, producing the backfiring heard on the ground seconds before the aeroplane fell from the clouds.

American reaction to the news of Rockne's death can be compared to the worldwide grief following the loss of Princess Diana. President Hoover termed it a national disaster. The King of Norway sent a delegation to the funeral and knighted Rockne posthumously. United States Army Chief of Staff Douglas MacArthur sent condolences, as did several state legislatures. It was said that, of America's 1,700 newspapers, 1,600 not only covered the story but ran leaders on the crash, and that trains entering South Bend, the home of Rockne's Notre Dame, stopped to allow the passengers to observe a minute's silence. In an athletics-mad era, sports writers voted the crash the story of the year. But the eulogies were for Rockne, not for aviation.

 

The public demanded an explanation and, in the meantime, the viability of the entire industry was called into question. As R.E.G. Davies wrote: "The aviation industry, TWA and Fokker could have had no greater adverse publicity had the victim been the president of the United States himself". The industry had only recently invested heavily in the change of focus from airmail to passenger carrying. After months of complex and expensive mergers and manipulations the trunk routes had at last been laid out. It was imperative that the public be given an explanation, and that the cause assigned be "satisfactory".

The investiation began immediately. Traditionally, the Aeronautics Branch of the US Department of Commerce followed a simple policy concerning public announcements about crashes it was charged to investigate. It did not make any. This crash was different, however, and, in attempting to placate the press without damaging the budding industry it had been formed to foster, the Aeronautics Branch made a proper mess of things. It first announced that Fry had severed the wing by overstressing the aeroplane in his effort to recover from a "glide". Hundreds, perhaps thousands of aeroplanes have been, and continue to be, lost that way, but this eventually would have led to public awareness that any pilot flying at above manoeuvring speed (about 102 m.p.h. for the F-10A) could break his machine by a simple movement of his arm. That quite plausible theory was quickly discarded. Next the Branch announced that ice thrown from a propeller hub had broken a blade, imposing a 100,000 lb load on the engine mount and breaking the wing. That theory lasted for the five days it took to dig the missing propeller out of the mud, intact.

Mute testimony to the tragedy

Mute testimony to the tragedy

 

So it went on. A week after the crash the Branch announced that NC999E's wing had became so loaded with ice that it broke from the sheer weight. That would not do either. Only small pieces of ice had been found near the wreck. As the investigation continued, the Branch, with its statutory mandate to "encourage, foster and promote civil aeronautics", increasingly shied away from "it can happen again" explanations.

May 4, 1931, was a day of high drama. In a tempestuous press conference Col Clarence M. Young, Assistant Secretary of Commerce for Aeronautics, barred all F-10s and F-10As built during 1929 from carrying passengers until they had been thoroughly inspected. No, he emphasised he was not grounding the airliners. They could still carry mail If the pilots wore parachutes. Young told incredulous reporters that his action in no way reflected on Fokker aircraft or their basic design or construction. The Government's sole concern was maintenance. No one bought the gentleman's protestations -and, doubtless, no-one was expected to buy them.

So, for neither the first nor the last time, "probable cause" was brokered. To mollIfy TWA, reference to its egregious maintenance, surely a "but for" cause of Rockne's death, was mentioned in only the most general terms. The Branch, controller of the process, suppressed its failure to inspect and its prior knowledge of F-10A faults, and the emerging airline industry had a "never again" explanation in "rotting" wooden wings. Only Anthony Fokker and the General Aviation Manufacturing Corporation, his General Motors-controlled licencee, really lost in the bargain. He never sold another F-10A. The American marker for his famous wooden-winged aeroplanes was permanently destroyed, and Fokker himself was soon ousted from the American company he had founded.

What tremendous force really caused the wing to sever?

As we have seen, NC999E was probably in a spiral dive when it broke up: Excessive speed almost certainly was a contributory cause of the accident, probably not through control mishandling but through flutter. Little understood at the time, flutter occurs when airspeed causes a wing or control surface to vibrate at its resonant frequency, and once initiated it can destroy the structure before lhe pilot can slow down. The F-10A had a bad reputation for buffeting, and the tampering with the ailerons, mentioned above, probably further increased the likelihood of flutter. Once begun it would almost instantly have twisted the wing from the Fokker like a banana from its bunch.

Privately, the Branch probably attributed the wing failure to fIutter, since it later issued a requirement for aileron counterbalancing, an anti-flutter measure, on all F-10As. A key question remained. Did the speed increase break the wing because the aeroplane was unsound? Were faulty design or maintenance contributing factors?

Severed wing from NC999E

Severed wing from NC999E

 

The Fokker mullicellular wing structure employed a series of glued wooden joints. Water is the enemy of that form of construction, and it was known in the industry that if the wood retained 20 per cent or more of moisture, the joint was likely to fail. The F-10A maintenance manual stressed; "it is absolutely necessary that the finish and covering of the wing be kept in good condition and waterproof ...". Months before, the Branch had been warned that difficully in inspecting F-10A wing interiors for water damage made the aeroplanes unsafe, but it did nothing about it.

Fifty-five years after the crash, E.C. "Red" Long, a former TWA mechanic, came forward to say that he had inspected NC999E a few days before he crash. "The wing panels were all loose on the wing. They were coming loose and it would take them days to fix it, and I said the airplane wasn't fit to fly and I wouldn't sign the log." The superintendent told Long that TWA needed the aircraft. "I don't know who signed the plane off, but they look the airplane...Nobody was safe in that airplane." Small wonder that, after the crash, government inspectors found evidence of delamination and failed joints and no wonder that F-10As experienced flutter-inducing buffeting as the slipstream swirled around the loose plywood panels, When the Branch and the Army finally examined the wing interior they found evidence of joint failures and delamination, but none of this was mentioned in the public announcement. 

By late June 1931, 20 of the 36 grounded F-10As were back in service, and five others would follow. There was no rejoicing.

The expensive, invasive and potentially destructive periodic inspections, imposed as a condition of their parole, made long-term eco- nomical operation impossible. Worse still, Fokker airliners, the reliable queens of the airways a few weeks before and representing investments totalling as much as $25m (in 2001 dollars) were now pariahs. Their only real rivals, the lookalike all-metal Ford Trimotors, were fatally stigmatised by their resemblance to "the aeroplane that killed Knute Rockne". Although the USA was sinking into the worst depression in its history, the newly organised and highly competitive trunk airlines had no choice. The race for replacements was on.

At first the twin-engined Boeing 247, ordered into production a year after the Rockne crash, was the unopposed front runner. With its all-metal stressed-skin construction and retractable undercarriage the 247 cruised at 161 m.p.h.,  a 30 percent increase over the F-10A and a 50 percent increase over the practical cruising speed of the Ford, Historians call it the "first modern airliner". Perhaps it was, but it also represented the squandering of available technological opportunity through a conservatism worthy of a steam locomotive designer. Its engines, not the largest available, were hobbled by the absence of variable-pitch propellers; its "one-out" performance was dangerously worse than that ot the F-10A; it lacked flaps and, in remarkable disregard of passenger comfort, its mainspar ran right through a cabin too small for economical operation and too cramped for a tall man to stand upright. Worst of all, it could accommodate only ten passengers.

Still, Boeing 247s cut 7 hours off the transcontinental flight time, providing airlines that flew them with a decisive advantage over those that did not. When Jack Frye, TWA's vice-president of operations (no relation to NC999E's pilot) attempted to buy 247s, Boeing turned him down. The airline would have to wait until Boeing had delivered 60 to its own sister company, United Air Lines, TWA's principal competitor. The two-year wait would put TWA out of the trunk-Iine business for good. That might have seemed a clever move in favor of an affiliated company, but, by driving their adversary to desperation, Boeing/United dealt their own companies such a blow as to knock Boeing clear out of the mass-produced-airliner business for 20 years,

Frye had no choice but to set about finding another manufacturer. His strength was his very weakness; the market created by the urgent need to replace scores of aeroplanes blighted by the Rockne crash. On August 2, 1932, he wrote to Donald Douglas of Douglas Aircraft: "Transcontinental & Western Air is interested in purchasing ten or more tri-motored transport planes. I am attaching our general performance specifications covering this equipment and would appreciate you advising whether your Company is interested in this manufacturing job.

"If so, approximately how long would it take to turn out the first plane for service tests?"

This is the most famous document in aviation history with the exception of Air Chief Marshal Dowding's May 16, 1940, letter to the British Undersecretary of State for Air, urging the husbanding of Fighter Command. What followed was one of the greatest examples of market-driven co-operative product development. Douglas accepted the challenge, and its representatives met with the TWA delegation, including CoI Charles Lindbergh, to hammer out the design. First to be go was TWA's suggestion of three engines. As Douglas's "Dutch" Kindelberger stressed, the Rockne crash had soured the public on that configuration. "Why build anything that even looks like a Fokker?"

By using the largest engines available, coupled to variable-pitch propellers, Douglas was able to meet Lindbergh's toughest requirement: that the aeroplane "must make satisfactory take-offs under good control at any TWA airport on any combination of two engines." With the trimotor configuration discarded, that meant safe take-off on one engine. This was an enormous advance in safety. Engine-out take-off procedure for the F-10A and the Ford Trimotor as specified in their operating manuals, was simple. If one engine so much as coughs, chop all three!

The end product was the prototype DC-1, first flown on July I,1933, 332 days after Jack Frye's letter. The DC-2, the slightly stretched production model, entered airline service a year later. For the first time an airliner embodied all-metal stressed-skin construction, a cantilever wing, fully NACA-cowled engines with variable-speed propellers, a retractable under-carriage and flaps. With a 170 m.p.h. cruising speed, 10 m.p.h. faster than the 247 and almost 50 m.p.h. faster than the Fokker, it was a success from the start, and almost totally eclipsed the 247. Two hundred DC-2s were built before production switched to the stretched version, the DC- 3.

The DC-3 turned air travel from an adventure into a business. Impressive as its performance was, what especially interested the airlines was the drastic decrease in cost per seat mile. British author Peter W. Brooks showed that the 21-passenger DC-3 achieved an astounding 47 percent reduction on the Fokker F. Vllb/3m the F-10A's tri-motored cousin, still being produced the year after the crash. All told, well over 10,000 DC-3s were built in the USA, plus some 2,000 in Russia and nearly 500 in Japan. As the C-47 it flew in just about every Allied airborne operation of the Second World War, played a significant part in the Berlin Airlift and flew operationally in the Korean and Vietnam wars. In the late 1940s and early 1950s several manufacturers offered "DC-3 replacements", but the DC-3 outlasted them all. The effects were far greater than the feats of this single type. The DC-2/DC- 3 series established the USA as the undisputed leader in airliner construction, a lead that has only recently been challenged by Airbus Industrie.

How much of this can be traced to the crash at Bazaar? Even if Rockne had landed safely at Los Angeles, we would not still be flying in three-engined wooden airliners at 120 m.p.h., but the development of the all-metal transport may well have been different. We have only to look at the Junkers Ju 52/3m, manufactured in its thousands from the mid-1930s, to see that the familiar airliner shape was not inevitable. Were it not for the market created by the Rockne crash, Douglas would not have built his masterpiece, the DC-3. Without the economy, safety and comfort of the DC- 3 worldwide air travel would have developed more slowly, and there might have been a slower acceptance of the stressed-skin low-wing monoplane as the key to high performance in military as well as civil aeroplanes.

A local cowboy poses at the original crash site marker.

A local cowboy poses at the original crash site marker.

 

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