Amphibious Nostalgia

TheVibration(1)(PxVolXI-No01)(Cover)By: Mark H Goodrich – Copyright 2014

Nothing brings about feelings of nostalgia in the aviation community more than stories about the glamour of days when flying boats brought comfort to air travel and access to the expanding civilized world. But like so many things seen in the rear view mirror, amphibious nostalgia clouds the memory of how things actually were. The glamour and comfort of lore simply did not exist. In fact, air travel in the flying boats of that era was noisy, bumpy, smelly, uncomfortable, unpredictable, and far less than safe.

Nonetheless, flying boats triggered the imagination of many with an interest in airplanes as they watched newsreels of the Pan Am Clippers leaving Key West and Dinner Key for ports of call in the Caribbean and South America, Port Washington for Shediac, Botwood and Ireland, and San Francisco for the far-flung islands of the Pacific.

The predecessor to Pan American Airways was just one of a worldwide gaggle of new airlines using flying boats to open routes of air transportation during the 1920s. Its principal competition, with a seven-year head start, was the Columbian airline SCATA, financed by the German government. Initial operating capital, route authorities and contracts for air mail service that enabled the ultimate success of Pan Am were provided by a thinly-veiled holding company of the US Government, in an effort to prevent Germany from establishing an advantage in the airline industry of the Americas. That financial and regulatory support from the US Government allowed the forerunner of Pan Am – Aviation Corporation of the Americas – to become established, and to grow quickly through the acquisition of small competitor airlines scattered throughout the Caribbean, Central and South America. Lost to history is that the holding company of ACA – later renamed Pan American Airways in 1931 – was initially United Aircraft & Transport Corporation, the wholly-owned transportation subsidiary of Boeing Airplane Company, and also the parent of other aviation companies that were to eventually become Pratt & Whitney, Chance-Vought, United Airlines, Hamilton-Standard and Sikorsky Aircraft.

Many airplane models defined “the age of the flying boats”, and covered a panoply of designs from manufacturers worldwide, including some amphibians and some only capable of water operations. Capacities varied from three to some forty passengers.

The reason that flying boats were used so extensively in the early days of aviation was simple – there were few runways in the developed world of the 1920s, and no runways in the undeveloped. Most major cities were along coastlines, and their harbors became the inexpensive runways not otherwise justified by the economics of a fledgling industry. It was the building of runways throughout the world during the Second World War that changed the equation, and allowed for continued airline development with the far more efficient designs possible using landing gear rather than seaworthy hulls.

Indeed, apart from the availability of runways, all design and operational considerations for airliners weigh against the use of flying boats, whether amphibians or not. The weight and shape of structure required for water operation eats into payload and performance, reducing it significantly from that of land-based airplanes of the same design era and with the same horsepower. Even with the jet-powered amphibians of today, payloads, optimum altitudes and cruise speeds are all compromised as a trade-off to allow for water operations, and still restrict their logical use to water rescue, oceanic patrol and fire-fighting.

Operations are also more difficult with water-capable airplanes, and require better-trained and experienced crew, even when operating an amphibian from a land-based runway. Water operations are even more critical, and combine the most challenging aspects of airplane and boat handling.

The hull of a flying boat produces relatively high levels of drag even in coordinated flight, but when allowed to slip or skid causes precious airspeed to evaporate in only seconds. In my days of training and checking pilots in large amphibians, I stressed procedures in every profile that were designed to maintain energy. Avoiding more than a modest and momentary yaw is of critical importance with multi-engine models, because loss of engine power without an immediate control input to offset asymmetric thrust can steal the energy necessary to successfully execute a go around, make the runway, or even stay above the velocity of minimum control. Further complicating the issue for ex-military types is that their manuals often specified climb and approach speeds that allowed no time margin for recognition and reaction, helping to explain the high operational loss numbers for PBYs and SA16s (also known as Canso and G-231s or CSR-110s above the 49th parallel).

As many fledgling pilots learned the hard way, the high pressures of water make speed control critical for both takeoff and landing. Adding a few knots for a smooth touchdown or liftoff on water can result in collapsing gear doors inward, or bending hull panels, a lesson all too often learned by crew as their airplane sank beneath them.

Night operations on water are substantially more difficult than on land. The rare submerged lighting for alignment can be helpful, but it tends to refract through the water even as landing light and environmental illumination reflects from the surfaces of waves and swells at varied and unpredictable angles. Crosswind control is hampered by wing-mounted floats that limit bank angles for a crosswind slip, and an absence of the directional stability that one gets from tires in contact with a runway. Unlike the modest damage caused by ground loops, water loops are often loss-of-airplane events.

In both night and day, judging altitude above water can easily confuse the most experienced pilot. Yet, once again, military procedures called for 360-degree overhead approaches, or low-altitude downwind legs and uninterrupted 180 degree turns to final, requiring that one judge speed, altitude, bank angle and descent rate by reference to a small piece of visible water. Despite that such procedures are fundamentally unsafe, civilians often adopt them non-critically because they are in the old military manuals.

Water operations create enormous challenges for both line maintenance and long-term airworthiness, as one recent crash exemplified all too well. Following an inflight wing separation on December 19, 2005, investigation revealed the accident airplane and its stable-mates to have all suffered from long-term corrosion beyond the capability for correction through normal inspection and maintenance. Even the simple act of checking oil and performing an A-check on water requires far more than just carrying a ladder to an airplane, and line maintenance technicians offer many stories of watching a dropped oil plug or wrench splash into the water below and disappear into the darkness.

The realities notwithstanding, nostalgia interferes with memory, analysis and logic, causing a recurring scenario in which some operator decides to “bring back the glamour”, by putting flying boats into passenger service. In the late 1970s, Chalk’s Ocean Airways – an airline then with 60-odd years of operating experience between Miami and the Caribbean – asked Grumman to take 13 of the 466 G64 Albatross airplanes that it had built for military services between 1947 and 1961, and convert them to allow civilian certification for use in passenger service. No Albatross had been previously certified under civilian regulations.

One reality of converting airplanes built for military use is an absence of design, materials and manufacturing data that can be used to support an honest effort. Military specifications are always focused on mission capability, and not on requirements of the civilian regulations underlying certification. Manufacturers, even if later still in business, predictably refuse to share original data for redesign efforts. Even when the original manufacturer is involved – as it was for the G64 to G111 conversion – access to and reliance upon original data, to the extent that it still exists, usually provides marginal benefits because of the differences in the design focus for military and civilian purposes, and the era of the original design decisions.

Often overlooked by those who seek to put civilian clothes on a military type is that most military airplanes are designed to operate in a maintenance-intensive environment. For the most part, military manuals – whether for inspection and maintenance, or operation – are long-outdated and woefully insufficient for use under the regulations and operating practices of civilian aviation. The presumptions in military aviation are that maintenance support will be available before and after each sortie, that parts will be available in new or overhauled condition as required, and that parts replacement will be the preferred course, rather than trouble-shooting and repair. Yet, as former military aircraft age, the availability of parts becomes problematic, as it does for diagnostic equipment, special tooling, and even support from manufacturers. In the case of the G64, for example, its Wright R-1820 engines have been without support from their manufacturer now for more than 50 years, ensuring that parts are old and reflect technology long superseded, with manuals and data of the manufacturer out of revision status for more than half a century.

The true facts are that few ex-military airplanes can be operated safely under the annual inspection system common to general aviation, and there is little guidance in former military manuals by which a progressive inspection system can be based. On airplanes like the G64, a failure to regularly inspect and maintain systems – such as electrically-actuated propellers – can easily result in loss of an airplane. And, there are no schools for training technicians and inspectors on old military types. Even when operated as “experimental” – without a civilian type certificate and under a series of restrictions including no operations for commercial purposes – it has become increasingly difficult to inspect, maintain and operate ex-military types to any reasonable standard of airworthiness and safety.

Despite these issues, the FAA routinely conditions operating approvals for ex-military types upon the use of ex-military manuals, once again reflecting a chasm between nostalgia and reality, even as refracted through the bureaucratic prism of regulatory personnel.

In the case of the G64, the rescue and patrol missions to which its original design was targeted did not include emphasis on payload, but rather range and loitering time with only crew onboard. Its design details were not aimed at long-term airworthiness, as the design process was initiated in 1944, when the immediate goal was placing airplanes into service with a minimum of delay. Those and other facts resulted in a redesign process for civilian certification in the late 1970s that could not be undertaken for conformance to even the minimum standards of Part 25, but rather to the predecessor CAR Part 4b as it existed on December 31, 1953, and then only with a variety of waivers, some using the infamous “equivalent level of safety” rationalization, and others bypassed with a wink and a nod.

Having flown the G64 series airplanes extensively – including training, checking and multiple crossings of the Pacific Ocean – I donned my engineering flight test hat and took a critical look at the G111 type certification process when first completed. I was underwhelmed, and my subsequent experience with the G111 airplanes validated all of my original concerns about representations that did not ring true. As is often the situation with supplemental or civilian certification of ex-military airplanes, the FAA required only a handful of minor modifications, reflecting quite clearly the rationalization that often takes place within regulatory agencies when a project is being funded by a politically connected corporate enterprise, like the owner of Chalk’s Oceanic Airways in the instant case.

For the most part, the required modifications were more form than substance, and in at least one instance, actually resulted in negative safety implications. One characteristic of Wright R-1820 series engines was a recurring momentary “hesitation” when power was initially reduced from takeoff to climb values. A requirement by the FAA that an auto-feather system be installed thus had the predictable effect of causing uncommanded shutdowns at a performance-critical time shortly after lift-off. Experienced pilots soon understood that safety was enhanced by disarming the mandated system before applying takeoff power.

Even without evaluating the bases for establishment by the military of its weight allowances – non-critically accepted by the FAA – payload with the redesign was modest, and far less than practical for a passenger-carrying airplane. Having been certified for 28 passengers, filling the passenger seats and standard baggage allowances on the G111 left a no-reserve endurance of about 90 minutes at a cruising speed of 135 knots. Common procedure therefore included winking at a falsified load manifest in order to carry reasonable fuel, and willful disregard of the effects that would have on performance and structural integrity.

In typical bureaucratic fashion, the G111 was likewise certified as conformant with Part 36 noise requirements, specifying a takeoff and initial climb protocol that, if followed, rendered the airplane unable to continue with an engine failure. Since the minimum certification standards to which grandfathered established no balked landing climb requirements, no such capability was tested, and arbitrary engine failure and takeoff safety speeds were assigned, neither of which bore any relationship to its represented function.

Even the adoption by the FAA of “G111” as the universal model identification was most puzzling. Despite that only 13 of 466 airplanes were modified by Grumman, all of the prior designations were superseded by one that simply does not apply to substantially all of the airplanes. It is not surprising that this has resulted in enormous misunderstandings – some situational, others accidental and a few intentional – about the real status of particular airplanes. Shortly after the re-designation by the FAA, I found myself at the center of one of the more humorous episodes revealing how the law of unintended consequences attended the FAA’s decision to confuse the airworthiness basis for several hundred airplanes in an apparent bow to nothing more than administrative convenience. I will share the details of that episode in an upcoming issue of Position Report.

Once Chalk’s began operating the G111 fleet in the early 1980s, the myths, tribal lore and nostalgia quickly gave way to operational realities, and the laws of physics. As should have been apparent in any due-diligence analysis, the airplane was slow, extremely inefficient as to load carrying and fuel burns, and a maintenance nightmare. Given that modern airports were in place throughout the Caribbean, allowing for operations at night and in poor weather using far more efficient land-based airplane types, the financial impracticability soon became all but impossible to ignore, and the recently modified and certified fleet was retired to desert storage.

A decade later, under new ownership, nostalgia again reared its head, and plans were made to convert the long-stored fleet of G111 airplanes to turbine power. But these plans – for all of the reasons set forth above and more – were soon revealed to offer no solution to the fundamental issues that plague modification programs for ex-military airplanes. With the wing-bending limitations, replacement of the radial engines with lighter turbo-propeller models further reduced the already insufficient payload capacity. Coupled with a necessity to derate the higher engine power, perform a comprehensive flight test protocol, alter the fuel system for kerosene, analyze the airworthiness of turbine engines in a salt water environment, and investigate the myriad unknowns concerning vibratory harmonics, all of the prior realities regarding long-term airworthiness and operational limitations remained.

Like many operators before and since, the airline finally realized that all it really had to sell with its amphibians was nostalgia. In a recurring scenario, amphibious nostalgia has always been proven a short-term business strategy certain to be doomed by economic realities.

Mark H. Goodrich – Copyright © 2014

“Amphibious Nostalgia” was first published in the February 2014 Issue (Vol 11 No 1) of Position Report magazine.