Bell Helicopter Progressing on OH-58F Programs

By By Douglas Nelms | May 1, 2011
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Bell Helicopter is moving forward with two upgrading/modification programs for the well-proven OH-58D Kiowa Warrior. These include a U.S. Army program begun last year to upgrade the OH-58D to the OH-58F model, and a Bell-funded program as its proposal for the Army’s projected Armed Aerial Scout (AAS) competition.

The OH-58F, an Army Acquisition II program, passed its Milestone B review in December 2010, and is now in the engineering manufacturing development phase. It is being upgraded through a cockpit and sensor upgrade program (CASUP). Improvements include repositioning the mast mounted sight to the nose under a Raytheon common sensor payload program; replacing two monochrome glass cockpit displays with three color displays with two 5 x 7-inch screens for each pilot and a 6 x 8-inch center display, and provide digital inter-cockpit communications, digital Hellfire upgrades, upgraded aircraft survivability equipment (ASE) and redesigned aircraft wiring harness. “The CASUP was driven out of the need to infuse technology into the cockpit and the systems of the aircraft,” according to Stephen Eppinette, Bell’s Army business development manager. “The current technology has been on there since the late ‘80s. [The OH-58D] was the first digitalized aircraft, so they needed to put some new technology into it.” The aircraft will also have a common missile warning system, health and usage monitoring system (HUMS) and enhanced weapons functionality via 1760 digital interface.

The new OH-58F will also replace the current “D” model’s control and display system 4 (CDS-4) with a new CDS-5. This greatly reduces the weight of the CDS-4 “black boxes” and gives the aircraft new mission computers, Eppinette said. He noted that other upgrades from the OH-58D to the OH-58F include dual-redundant FADEC engine controls to the current 650-shp Rolls-Royce T703-AD-700A engine and Level 2 manned/unmanned controls linking the aircraft to unmanned platforms. The Level 2 controls are also being installed on current OH-58Ds, he added. The “F” model is currently in a four-year development program, with the Army working with the major OEMs—Bell, Honeywell, Rolls-Royce—to integrate all the upgrades into the aircraft, Eppinette said.


Lt. Col. Scott Rauer, the Kiowa Warrior product manager, said that the OH-58F CASUP “really challenges the methods that we use in this business to get the aircraft modified. With the Army taking the role as lead systems integrator, it challenges the traditional paradigm where the mission equipment manufacturer takes the lead and develops the aircraft from start to finish. In this case, the government is coordinating the efforts of four major developers and is doing this as fast as possible at a very low dollar value, to be as flexible and responsive and fiscally responsible as we can possibly be.” Col. Robert Grigsby, project manager for armed scout helicopters, said that the OH-58F program would allow the Army “to get to a point where we can meet its requirements until 2015 as it sits right now.” Initial delivery to active duty units is scheduled for 2015.

While the initial OH-58F is an Army program, Bell is developing its own program in the form of the OH-58F Block II aircraft that will provide significant performance enhancements. These include a new engine, new main and tail rotor systems and a new transmission. The Block II aircraft initially will feature a Honeywell HTS900 engine rated at just under 1,000 shp, a Bell 427 tail rotor and a 407 main rotor and transmission. Eppinette said that Bell bought an old OH-58A, converted it to a D model, then put in the Honeywell engine and new rotor and transmission systems. “This will be the Block II demonstrator. It gives the Army another upgrade on top of what they are doing with the F model, and is a low-risk, low-cost, best value approach for both the Army and the taxpayer.”

By going from the OH-58F to the OH-58F Block II, the Army will be able “to improve their manned Armed Scout capability with no fleet changeover costs. [The Army can] then take the dollars saved and invest more S&T [science and technology] dollars into the future of Army Aviation,” he said. The new Block II demonstrator will be taken to Colorado in May for “hot and high” trials. Eppinette noted that Bell is also building a second demonstrator that will be powered by an upgraded Rolls-Royce engine. As for the well-proven OH-58D, it is doing “very, very well,” Eppinette said, with over 750,000 combat hours going back to Desert Storm and two million total flight hours. Bell is currently providing crash damage repairs on OH-58D aircraft in support of the Corpus Christi (Texas) Army Depot (CCAD), as well as producing new OH-58D cabins at its Amarillo production facility, then sending them down to the CCAD for re-builds. “We’ll deliver the first cabin in early summer, (with) five more cabins that we are building up at Amarillo,” he said.

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