Maritime Option to the Airline Pilot Shortage

Analysts from the international airline industry are projecting a shortage of over 500,000 pilots over the next 15 years, as commercial aircraft become more complex and require more comprehensive pilot training. A fast maritime option that involves a less complex technology and less comprehensive pilot training appears possible on several domestic and international routes that connect between coastal cities.

Introduction

Within the next decade and beyond, the international airline industry faces a looming shortage of qualified pilots as demand for fast passenger transportation increases. On some overland routes, high speed trains capable of excess of 300 km/hour carry intercity passengers on select routes in France, Spain, Japan and China. A still evolving technology called Hyperloop involves high-speed trains that travel inside extended-distance airtight tubes, with low-pressure upstream and high-pressure downstream. Hyperloop technology can be built over land as well as underwater with some installation likely being in operation within the next decade.

High-speed transportation technology such as TGV trains, maglev trains and Hyperloop require a dedicated right-of-way and considerable construction cost that only makes these technologies feasible along comparatively short routes between very densely population metropolitan areas. The airline industry operates short-haul flights over the same routes. With a looming shortage of airline pilots, high-speed trains would capture segments of the short-haul flight market. The maritime sector can offer a technology that requires minimal infrastructure investment and would be capable of providing short-haul, high-speed intercity passenger transportation service between less densely populated coastal cities.

Pilot training

Commercial airline pilots need to undergo many years of comprehensive and rigorous training, beginning with acquiring competence in the operation of small single-piston-engine, propeller-driven aircraft. Over time and as each pilot gains experience, they graduate to larger twin-engine aircraft. Several recent incidents that involved large commercial passenger aircraft carrying passengers have raised questions about pilot training. On June 1, 2009, Air France flight 447 from Rio de Janeiro to Paris disappeared from radar and crashed into the Atlantic Ocean after the junior pilot had put the aircraft into a stall that pilots are supposed to be trained to correct. 

During the final minutes of Lion Air domestic short-haul flight 610 from Jakarta to an island coastal city, pilots were consulting flight manuals for the Boeing 737 Max 8 aircraft to respond to related flight problems. Shortly after on March 10 2019, the crash of Ethiopian Airlines flight 302 involved the Boeing 737 Max 8 that were subsequently ordered removed from service. The lack of intercity transportation infrastructure across Africa makes airline transportation essential between inland African cities, with a high-speed maritime option between coastal cities presently served by domestic and international short-haul flights.

The Maritime Vehicle

Despite many years of ongoing research and development involving small wing-in-ground (WIG) effect craft in West Germany, the world became aware of such technology as a result of the Soviet “Ekranoplan” built for military purposes. At the present day, a small handful of builders offer small versions of the technology capable of carrying eight to 12 passengers, with Wing-Ship of South Korea having built and demonstrated a 50-seat version of the technology. The builder in Singapore has plans to offer a 24-seat vehicle while Tandem Wing of Germany has proposed a 100-seat version of their unique technology.

The triangular wing planes built in South Korea and Singapore operate at peak energy efficiency when traveling at an elevation of five percent of wingspan, with the ability to adjust wing flaps to climb at an elevation of 40 percent of wingspan or 10m for wingspan of 25m. The tandem wing vehicle can apparently climb to 20 percent of the lengthwise measurement of the wing chord, allowing a vehicle of 100m length and 80m chord to climb to 16m above ocean surface. A reel-out mini-glider flying at 200m elevation with a camera would allow pilots to plot a safe path.

Speed and Efficiency

When traveling at five percent of wingspan measurement above calm sea, the WIG. vehicle is calculated as using 30 to 35 percent of the fuel of the identical weight of aircraft using the identical engines and propellers. Rising to full elevation reduces fuel usage to that of the equivalent aircraft traveling at the same speed. However, the design layout of the WIG. vehicle allows it to use a propeller the diameter of a helicopter rotor and achieve significantly superior propulsive efficiency. When traveling into a headwind, wind speed increases with elevation, reducing WIG. fuel consumption compared to an aircraft.

Unlike commercial aircraft above a certain size that are required to use at least two engines, a large WIG. vehicle could use a single engine, including a single geared turbofan engine that could raise its speed to that of a commercial jet aircraft. To assure optimal propulsive efficiency, a single large roof-mounted turbine engine driving into tension-rod based transfer drive mechanisms and reduction gearing could drive a pair of geared propulsion fans. Even when traveling at jet speed at maximum elevation above sea level, a WIG. vehicle could still deliver superior energy efficiency than a commercial airplane.

Hybrid WIG

Aeronautical research undertaken at Massachusetts Institute of Technology (MIT) at Boston included a concept twin-fuselage plane built with an aeronautical roof profile. That profile allowed the fuselage upper surface to provide 40 to 60 percent of the lift required to fly the plane, using shortened wings. Combining the MIT. twin fuselage concept with ground effect wings offers the possibility of a vehicle capable of partially flying in ground effect mode across vast stretches of rough ocean surface, at much higher elevation than WIG. planes and at speeds of 200 to 300 miles per hour.

Propelled by twin counter-rotating propellers the diameter of helicopter rotors to achieve high propulsive efficiency, such a vehicle could travel 50 percent to double the distance using the same quantity of fuel as the equivalent weight of aircraft flying at 10,000 feet altitude. For WIG operation, the aerodynamic roof could be built to a channel profile, with “winglets” extending the entire fuselage length to enhance flight performance. While the Australian built “Hover-wing” vehicle can travel at three-meter elevation above waves of four meters, flight over rough ocean surface would be problematic for WIG technology, except for the possible solution from MIT. 

Efficient Engines

To save weight and complexity, commercial aircraft dispense with the energy saving regenerator that reuses exhaust heat productively. However, some helicopters do use the regenerator and there is potential to include the regenerator in turbine engine designs destined for application in large WIG vehicles. The combination of the regenerator and propellers the diameter of helicopter rotors promises to greatly enhance the fuel efficiency of future mega-size WIG vehicles, including versions that use the MIT fuselage concept. Research is underway at General Electric involving compact high-temperature closed-cycle turbine engines that use silicon-carbide in the heat exchangers.

Vehicle Economics

The airline industry operates small aircraft on short-haul routes with multiple daily departures and fewer departures of large aircraft on long routes. In terms of economics, small planes can carry as many daily passengers as large airplanes. Using this trend, WIG vehicles would compete with short-haul aircraft between coastal cities on journeys that involve travel across large expanses of water. In long-haul operation, WIG vehicles that exceed the take-off weight of large commercial aircraft, would by comparison travel at lower speed, use less fuel and carry greater payload capacity to compensate for higher crew cost.

Autonomous Control

Incorporating advances in autonomous vehicle technology into long-haul WIG vehicles would reduce crew cost when carrying high-priority containers in trans-Pacific service. Perhaps there may be future scope to develop small, short-distance high-speed hydrofoil vehicles to allow crew with radio control technology to remotely pilot the WIG vehicles when departing from port, also upon approach to port. Future operation of autonomous ships will allow computer directed traffic control to manage arrival and departure of slow moving and fast moving maritime vehicles in the port vicinity, perhaps extending up to 30 nautical miles from land. 

Pilot Training

WIG technology involves lower complexity than aircraft along with stall-proof flight characteristics. Even very large versions of WIG vehicles built to 2,000 tons lift-off weight and capable of traveling above ocean at commercial airline speed, would be less complex to operate than the airliner. WIG vehicle pilot training and certification would therefore less costly, less time consuming and less comprehensive than commercial airline pilot training and certification. Pilot training would include operation of a reel-in reel-out mini-glider carrying a camera at up to 300m elevation to help guide pilots following departure from port and upon approach to port.

Potential American Routes

Large WIG vehicles capable of jet speed could operate a variety of routes internationally. In the U.S., the cancellation of the California high-speed rail program makes Los Angeles – San Francisco a possible future WIG route, with an option for a San Francisco – Hawaii service. In the Gulf of Mexico region, fast WIG vehicles could operate between Tampa Bay and Galveston Bay carrying passengers between Tampa – St Petersburg and Houston. On the American east coast, fast WIG vehicles could operate Boston – Norfolk, Boston – Miami, Norfolk – Miami, New York City – Norfolk and New York City – Miami. 

Trans-Atlantic Service

The premium trans-Atlantic route would connect Boston to Bristol, U.K., or Cardiff, Wales, where railway connections for passenger and freight transportation into Europe via the Channel Tunnel would be available. Maritime traffic density would be much lower between the Bristol Channel and Boston than on a voyage via the English Channel and Thames River to London. On 12-hour duration overnight westbound journeys, a late evening departure from Bristol or Cardiff would translate to a breakfast hour arrival at Boston. A 2,000-ton concept mixed-service vehicle could carry containers on the lower level(s) with an upper section devoted to passengers.

Conclusions

The looming future shortage of airline pilots is further aggravated by increasing operational complexity of commercial aircraft. A wide-body WIG plane built with MIT designed upper fuselage partial lift capability would safely be able to travel above ocean surface and over most ocean waves at commuter plane speeds and burn about half the fuel of the commuter plane. The combination of a future pilot shortage, higher payload capacity, higher fuel efficiency, less vehicle complexity and easier pilot training could encourage development and market acceptance of large-scale WIG commercial service transport planes.