The V-22's price is hovering millions above the original target and Pentagon orders have stabilized at a lower-than-anticipated rate, but the Bell/Boeing tiltrotor team is optimistic about its sales prospects.

The largest forthcoming tender could be for the U.S. Navy's Carrier Onboard Delivery (COD) replacement program, but Bell/Boeing is making the case that the Osprey is more than just a high-priced transport. The company is testing its ability to conduct aerial refueling missions as the Pentagon considers other possible missions, such as hosting communications hardware or electronic-attack systems on the platform.

The Bell/Boeing team is eyeing sales around the world; U.S. Marine Corps Col. Greg Masiello presented a list of at least 15 prospects at the Paris air show in June, and near-term candidates include Israel, the United Arab Emirates and Japan. But each of the potential customers—largely countries in the Pacific or Middle East—are likely to only purchase a handful. In aggregate, these sales could carry the program forward. Masiello said foreign sales could account for 100 aircraft over 10 years.

But a Navy buy would bolster the production lines at Boeing in Philadelphia and Bell in Amarillo, Texas. The Navy signed a $6.5 billion, multiyear contract with the team this summer for the next 99 V-22s at a target price of $70 million, more than $10 million higher than government and industry officials hoped for while the program was in development. That price is locked in despite a production-rate drop from 40 V-22s delivered this year to 35 next year, and then a slump into the 20s.

Against this backdrop, the industry team is pressing forward with plans to expand the Osprey's capabilities. Among its future missions is aerial refueling. The industry team is confident the tiltrotor can potentially fill what one official calls a “capability gap” in tactical aerial refueling and safely refuel F/A-18 aircraft midair. Bell/Boeing funded the first midair proximity test between the two Aug. 29. That mission is now handled by the KC-130 series operated by the Marine Corps, although Navy fighters can also be refueled by the KC-10 fleet and select KC-135s with a hose-and-drogue delivery system.

During an Aug. 29 flight trail, a Hornet flew within 30 ft. of the MV-22's drogue chute in a lateral offset position at 8,000-ft. altitude, says Chad Sparks, advanced derivatives manager for Bell/Boeing. This was the fourth in a series of tests paid for by Bell/Boeing as the team examines alternative missions.

The Marine Corps is the primary customer for the aircraft with a program of 360 aircraft, with the U.S. Air Force's fleet at 50 to replace its retired MH-53 Pave Lows. Pentagon officials have always said the Navy anticipated buying 48 or more Ospreys, but a competition is likely to come for the C-2 Greyhound replacement. Northrop Grumman is proposing a refurbished C-2 that incorporates improvements from the E-2D program.

The Bell/Boeing team hopes the Navy or Marine Corps will fund more tests to include contact between the refueler and receiver and, eventually, passage of fuel between the two, says Ken Karika, business development manager.

Prior to the Aug. 29 flight, the company validated the ability to extend and retract the refueling hose and drogue, a Cobham model also used by the Marine Corps KC-130 fleet. The team had collected data on the behavior of the Super Hornet in the MV-22's wake as well. “Pilots didn't report any significant wake turbulence,” Sparks says, noting that the feedback validated models and earlier input from the pilot of a surrogate used to study the MV-22's wake.

During the Aug. 29 test, the two aircraft were traveling at 210 kt. The high-speed version of the hose/drogue refueling system is designed to be deployed at 185 kt. and function up to 250 kt., Sparks says.

For that test, the V-22 was functioning in airplane mode. Sparks explains the company prioritized testing for the Super Hornet specifically to address concerns that the Pentagon could need more refuelers for high-speed receivers. The Osprey could be used, like the KC-130, as a refueler for rotary-wing aircraft, as well.

A preliminary test is slated for this week, Sparks says. Officials will extend and retract the hose and conduct low-speed proximity tests with no contact between the refueler and receiver.

Rotary-wing refueling will require a separate drogue specific to helicopters, and Sparks says the target is to operate around 105 kt., with the aircraft in helicopter mode operating with a partially converted nacelle.

The refueling system makes use of onboard tanks as well as a roll-on/roll-off bladder, adds Sparks. The hose extends 90 ft., about 80 ft. from the end of the ramp of the MV-22. The operator must open the ramp to extend the refueling hose; once extended, the ramp is then raised back up with the top ramp door left open, he says.

Depending on mission profile, the system can off-load up to 12,000 lb. of fuel, says Karika.

The prototype design used in the Aug. 29 test includes a refueling system operator station near the ramp, but Karika says this can be placed where the customer requires.

The aerial refueling concept grew out of technical work done in 2007 to support operations in Iraq to enable Marine operators to use the Osprey as a ground-based refueler for helicopters and ground vehicles.