News

2017-06-08

C-40 Clippers Hitting Their Stride

Designed to offer mission flexibility, the C-40A is a versatile FAA-certified 737-700 convertible/”combi” aircraft, optimised to transport passengers and cargo around the globe.

The aircraft can be configured to carry all-passengers, all-cargo, or a combination of both. The C-40A is part of Boeing’s C-40 series of aircraft, which also includes the C-40B and C-40C. The C-40A is currently on offer as the C-40Ai to countries around the world. It provides the right capabilities to meet mission sensitive rapid response requirements while providing critical logistics support.

The Navy required a Navy Unique Fleet Essential Airlift Replacement Aircraft (the NUFEA-RA Programme). This aircraft, since designated the C-40A, was required to replace the aging C-9 fleet. Boeing offered the 737-700 new technology aircraft in response to the Navy’s request for proposal. The Navy did not request and Boeing did not specify any particular equipment to be designated by manufacturer and model number except the basic aircraft itself. Instead, general capabilities and performance requirements were specified.

The C-40A is a derivative of the 737-700C Convertible that will accommodate 120 passengers, eight pallets of cargo, or a combination configuration consisting of three pallets and 70 passengers. The 737-700C is modified with a large cargo door and the strengthened wings and landing gear of the 737-800. The aircraft has a range of 3,400 NM with 5,000 lbs. of cargo and provides long range, high priority logistical airlift in support of Fleet activities.

The US Congress approved funding for the first four aircraft in 1997. A contract for two C-40As was signed in August 1997, with an option for a third. Delivery of the first aircraft was made in December 2000. On July 30, 1999, Boeing Defense and Space Group was awarded a US$43,700,000 modification to the previously awarded contract for the procurement of one C-40A aircraft, to be delivered by August 2001. Five aircraft have been ordered; a sixth aircraft was funded in the fiscal year 2001 budget.

The C-40A is able to carry 121 passengers or 40,000 pounds of cargo, compared with 90 passengers or 30,000 pounds for the C-9. In addition, the maximum range for the Clipper is approximately 1,500 miles more than the C-9.

It has a fully digital “glass” cockpit that will allow for future growth and is also fitted with a head-up display, allowing pilots to keep their eyes up and outside in low-visibility approaches. One major improvement is the C-40A’s navigation system includes GPS, which will aid in approaches to airports with older, less reliable ground systems. The cargo area in the C-40A will be available in three variations: all passenger with a capacity of 121, all cargo with a carrying capability of eight pallets totalling 40,000 pounds, and a combination rig that will allow for 70 passengers and three pallets. In this mode, the cargo compartment is sealed to protect passengers and crews from the potential danger of hazardous cargo.

The U.S. Naval Reserve Fleet Logistics Support Wing operated 29 of the old DC-9 based C-9B Skytrain Combi aircraft (90 passengers, 30,000 pound limit, shorter range than C-40A), providing high-priority cargo and passenger airlift for the U.S. Navy fleet worldwide. The C-9s were operated by seven Naval Reserve units nationwide, and provided 85 per cent of the worldwide airlift requirements for the entire Navy. The Navy’s C-40A replacements were initially ordered and delivered with standard wings, but airline usage has shown significant fuel-savings benefits from adding turned-up “winglets” on the end. New-build C-40As from aircraft #9 onward have those winglets, and earlier C-40As have been retrofitted.

The USAF is also buying C-40s. They aim to replace their DC-9 derived C-9As, and their 4 727-derived C-22Bs. The USAF C-40Bs operate as an “office in the sky” for senior military and government leaders. C-40Bs are equipped with the Connexion system, providing secure in-flight broadband connectivity that includes data/video transmit and receive capability. Its visual profile matches the C-40C’s and new-build C-40As, with turned up winglets. Boeing delivered the last C-40B in 2005.

The C-40C is the USAF’s counterpart to the Navy’s C-40A. Both types are certified to operate in one of three configurations: an all-passenger (121) configuration; an all-cargo configuration of up to eight pallets; or a combination (“combi”) configuration that will accommodate up to three cargo pallets and 70 passengers. Unlike its C-40A counterpart, the C-40C has always used the common 737-700 configuration with turned-up winglets.

The 737-700 is assembled from 375,000 parts, which could be a problem for the Navy’s supply system if required to purchase and order spares for the fleet. But the Navy will be able to partner with private industry-airline and cargo carriers-to purchase parts under a Contract Logistics Supply system. A pool of parts will be created that all partners can access quickly, and this will lower costs because we won’t have to stock millions of dollars of parts. The Navy will continue to do its own maintenance.

The first Clipper has been certified by the Federal Aviation Administration, much like civilian cargo and passenger aircraft. Because this is a commercial off-the-shelf aircraft, and because the value for potential resale is higher, it made sense to accept FAA certification.

The C-40 comes in three variants; the C-40A is a Navy aircraft, while its counterpart C-40C and executive/ VIP C-40Bs are USAF planes. The USAF’s C-40 leasing contracts have been a source of some controversy, but the program has continued, alongside Air Force and Navy buys. In June 2010, the US Navy placed a C-40A contractor logistics support (CLS) order with Boeing. The five-year contract is valued at $80.9m.

The aircraft are certified to operate in three configurations - all-passenger (121 passengers), all-cargo (up to eight pallets) or combination (‘combi’) configuration that will accommodate up to three cargo pallets and 70 passengers on the main deck. The US Naval Reserve will staff and operate the aircraft.

The aircraft, based on a civil airline design, is suitable for deployment to civil airports or military air bases. It has an aluminium alloy fail-safe fuselage and wing structure and incorporates the strengthened wing design as used on the 737-800 and Boeing Business Jet. The undercarriage of the aircraft has been strengthened to accommodate the increased gross weight. The hydraulically retractable tricycle-type landing gear is fitted with Boeing shock absorbers and Honeywell or Goodrich brakes.

The two-crew flight deck of the Clipper retains the features of the glass cockpit installed in the commercial 737-700 aircraft with a Honeywell common display system and five flat panel liquid crystal display screens. Systems include a dual flight management system and an integrated global positioning system.

Technical Specifications

Engines Advanced-technology CFM56-7

Maximum Sea-Level Static Thrust Performance 24,000 lbs

Maximum Gross Weight: Takeoff 171,000 lbs

Maximum Gross Weight: Landing 134,000 lbs

Maximum Gross Weight: Zero fuel 126,000 lbs

Fuel Capacity 6,875 gal

Lower Hold Cargo Volume 885 cu Ft

Schedule Reliability 99.58%

Range 3,200-nmi (121 passengers, or 36,000-lb main deck cargo, or 70 passengers/15,000-lb in combi configuration)

Cruise Speed 0.78 Mach to 0.82 Mach

Altitude Capability 41,000 ft