Airborne (1997) (36 page)

Lockheed Martin is in the enviable position of having something in the C-130J that people badly want, and will pay good money to get. Interest in this new bird resembles nothing so much as a runaway freight train, as the Lockheed Martin sales team is working hard to keep up with the inquiries from around the world. Already the RAF, RAAF, and Royal New Zealand Air Force (RNZAF) have firm orders or options for a total of 65 aircraft. This is a lot for an airplane that has not even competed testing and certification!

You might be wondering just why all this excitement is being generated over a modified version of an already forty-year-old transport aircraft. It’s a good question, actually, and deserves an answer. The most obvious one is that this is an airplane that needs to be built. As early as the 1970s, the USAF was considering the possibility of building a jet-powered replacement for the C-130. Under the Advanced Medium Short Takeoff and Landing Transport (AMST) program, two pairs of prototype aircraft were produced (the Boeing YC-14 and the McDonnell Douglas YC-15), but they never went into production. Both pairs of aircraft did great and wonderful things in testing, but not enough to justify producing them instead of additional C-130Hs. In fact, the H-model Hercules has been in production for over thirty years and the only thing that will replace it now is another C-130! It will be a greatly improved Herky, though, and amazingly, will not cost any more than the C-130H model that it will replace. The core philosophy behind the new design is something that a Lockheed Martin engineer told me on a visit to the Marietta, Georgia, plant. He said, “The only reason we touched anything on the C-130J was if it improved performance and reduced cost!”

Externally, the most noticeable differences in the C-130J are the propellers. In place of the four-bladed props, with flat blades and squared-off tips, there are six-bladed props with graceful compound curvature that tells an engineer that the most advanced computer-aided design went into their shaping. Actually, they look a lot like the blades of a modern submarine propeller. Made of advanced composite materials, these blades not only are more efficient than those on the -H, but also have a greatly reduced radar signature.

The new Allison AE2100D3 engines (the same basic engine that will power the V-22 Osprey tilt-rotor transport) have digital electronic controls, and provide 29 percent more power than the engines on the C-130H with an 18 percent improvement in fuel efficiency. Since fuel is one of the biggest costs of operating an aircraft, that 18 percent is a whopping number to cash-starved air forces around the world. Economy aside, though, the real improvement of the new engines is their ability to sustain their power in high altitude and temperature conditions. For aircrews, this means shorter takeoffs with larger payloads, which is the name of the game in the theater air transport business. Also, the new engines are virtually smokeless, though the noise footprint is about the same. Finally, the plumbing of the fuel system has been simplified, with provisions being provided for quick modification to a tanker configuration with the addition of fuel bladders.

Most of the improvements to the C-130J are on the inside, beginning with a new two-man flight deck. In effect, the navigator and flight engineer have been replaced by software and electronics. The pilot and copilot sit in front of four multi-function color flat-panel screens, which replace dozens of “steam-gauge” instruments. These screens are programmable displays that present the specific information needed for any phase of flight or emergency. These can include primary flight displays, weather radar data, digital ground maps, navigation and SKE displays, or malfunction warnings. Like fighter pilots, the C-130 flight crew also have “heads-up displays” that project key information into the field of view, allowing the pilots to focus their attention on the flight path outside the window. There is provision for a third seat on the flight deck, with space, weight, and power allocated for a systems operator workstation, which might be required on special-mission aircraft.

The basic flight control systems of the Hercules, though, have not been altered. The old-style control yoke has been left unchanged, and even the classic nose gear steering wheel has been left untouched. What has changed are some of the supporting systems, especially those having to do with the new engines and display systems. In the C-130J, the throttles are no longer connected directly to the engines. Instead, a system called FADEC (Full Authority Digital Engine Control) takes the throttle and control inputs from the crew, as well as environmental inputs from air data sensors, and uses a computer to control the engines and props. This system, as much as any other part of the -J design, is responsible for the improved economy and performance of the new bird.

One of the prototype C-130J Hercules Transports on the Lockheed Martin ramp at Marietta, Georgia. This new-generation Hercules is just going into production for air forces around the world.

All of these systems are tied together into a single network that allows the data generated by one system to be used by another. There are two independent mission computers, and the data bus uses redundant channels routed by different paths, providing increased damage resistance. For example, the GPS receiver, which is built into the inertial navigation system, can generate data which can be used by a variety of other onboard equipment ranging from the SKE to the autopilot. This scheme of tying everything together on a single digital data bus also has other advantages. The hundreds of analog control signals, each of which used to require an individual pair of copper wires on the C-130H, have been replaced by a couple of strands of data bus cable running the length of the aircraft. This eliminates miles of wiring, saves tons of weight, and greatly reduces the amount of hand labor needed to assemble the aircraft.

Lockheed Martin estimates that the prototype J-model aircraft took something between 20 and 25 percent fewer man-hours to produce than the fully mature C-130H. This factor alone guarantees that the new Hercules will cost no more than the older H-model. It also has a humorous (and practical) side as well. The removal of all that wiring resulted in a lightening of over 600 lb/272 kg in the -J’s cockpit area alone, and this created a problem. There was no way to balance the new aircraft in flight without it carrying some kind of ballast in the nose, so the previously optional cockpit ballistic armor has now become standard, even on the commercial models!

Back in the 1950s, the original YC-130A prototype was one of the first aircraft designed with input from the infant science of human factors engineering. Today, the new C-130J incorporates all the lessons that the Lockheed Martin human factors engineers have learned in the intervening forty years, and the results show. The two-man cockpit has been laid out to allow either crew member to fully operate the aircraft from either seat. In addition, the crew chief/loadmaster has been given a whole host of improvements to make his/her life easier. This is vital since there are only the three crew members to operate all the systems on this new Hercules. Other improvements have also been made in cargo handling. For example, the attachment points on the cargo ramp have been strengthened to allow opening the ramp during flight at speeds up to 250 kn/463 kph.

The advanced cockpit of the new-generation C-130J Hercules. While digital systems have replaced most of the old analog gauges, the basic flight controls remain unchanged.

JOHN D
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GRESHAM

Another improvement is the idea of reducing the amount of maintenance time required to get the C-130J into the air. One goal of the C-130J program is a 50 percent reduction in maintenance man-hours per flight hour (compared to the C-130E). Combined with the reduced aircrew requirement, this translates to a 38 percent reduction in squadron personnel requirements (from 661 to 406). When you consider that the most junior enlisted personnel in the U.S. cost over $100,000 per year to pay, clothe, and feed, that means a personnel savings of at least $25.5 million a year per squadron, which is a lot! Combine it with savings from fuel and other areas, and you can understand why air forces everywhere are lining up to buy this new aircraft.

As of late 1996, the C-130J program is going well, with all four prototype aircraft flying actively in the test and certification program. The first flight of the C-130J was successfully completed on June 4th, 1996, and Lockheed plans to deliver two aircraft a month for many years to come. Thus far, Lockheed Martin can see sales and requirements for over three hundred of the new birds, with more orders coming in every day. Perhaps the only criticism of the new Herky Bird is the one that comes from some aviation visionaries who think that something even better than the -J is needed. They speak of an aircraft with a C-130 payload, but with the vertical takeoff and flight performance characteristics of the V-22 Osprey.
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While this is a far-reaching concept, it is clearly beyond the current state of the art, as well as the experience base with tilt-rotor aircraft. For now, the C-130J is the finest medium transport in the world, and will probably stay that way for another generation. Who knows, there may even be another version of Hercules someday.

 

 

 

Notwithstanding the above comment, the purpose of aerial refueling is to extend the range of tactical, bomber, or transport aircraft beyond the limits of their own fuel capacity. A secondary, but vital and lifesaving, mission is to assist battle-damaged aircraft, which may be leaking fuel heavily, to return safely to base. One retired USAF officer I know once told me that aerial refueling of battle-damaged aircraft over the last four decades has probably saved more money than has been spent on all the tankers ever built! However you view it, refueling tankers have proved their worth in war and peace. It is hardly simple or easy, though. Aerial refueling, especially at night and in bad weather, is an ultimate test of a pilot’s nerve and skill. Only a night carrier landing can compare with it for sheer difficulty. The aircraft receiving fuel must hold a precise, tight formation in the turbulent wake of a (usually) much larger aircraft, for several minutes. Pilot error or bad luck can result in severe damage to the receiving aircraft, or even a fiery collision. Also, tanker operations are intensely mathematical planning exercises, requiring the ability to manage rates of fuel consumption, range and speed calculations, and precise navigation. There is no room for error. A miscalculation can easily lead to the loss of costly aircraft and irreplaceable flight crews.

There are two basic approaches to aerial refueling. The first, which was largely an invention of the Air Force, involves specialized tanker aircraft equipped with a rigid telescoping “flying boom.” The boom is extended to fit into a special receptacle on top of the receiving aircraft. The kind of tankers using this system were largely an invention of the USAF. The boom is equipped with steering fins controlled by an enlisted airman in a compartment at the tail of the aircraft. There he or she works with a view aft through a large window. This window, by the way, is a favorite vantage point for the handful of aerial photographers allowed to fly on tanker missions. The second method is the simpler “probe and drogue” method favored by the U.S. Navy, the USMC, the RAF, NATO, and the rest of the world’s leading air forces (at least those that can afford the formidable cost of aerial refueling). The tanker reels out a hose with a cone-shaped basket (the “drogue”) at the end, and the receiving aircraft spears the drogue with a fixed or retractable refueling probe. This adds weight and possibly drag to the receiving aircraft, but requires no specialist operator onboard the tanker, and allows a greater separation between the aircraft.