The T63 engine powers the H-58 and H-6 helicopters-both of which are being significantly downsized. The T63 is manufactured by Allison and is similar to the commercial 250 Allison engine, which powers several commercial aircraft, including the Bell 206 and 487 helicopters. The Bell model 206 YOH-4A of 1961 was powered by an Allison T63-A-5 250 shp turbine engine. It evolved into the successful Bell Model 206A Jet Ranger. The OH-6A was powered by a single Allison T63-A-5A 285 shp turboshaft engine, and had a cruising speed of 144 mph (125 knots).

DOD had 11 percent of the 21,000 engine population as of 1997. The Army did 84 percent of its T63 depot workload at its Corpus Christi Army Depot in 1997, with the remaining workload contracted out to the private sector. As of 1997 there were eight potential sources of repair for this engine-three having previous T63 experience and the remaining having experience with the Allison 250. The T63-A-720 is an engine type produced for the military and has a close equivalency to a 250-C20C civilian engine. The Federal Aviation Administration Type Certificate Data Sheet for the 250 series Rolls Royce Allison engines notes that certain military engines are eligible for use under the Civil Type Certificate if the civilian model is stamped on the data plate next to the military model designation, and, certain modifications are made prior to civilian use.

More commercial turbine engine helicopters are powered by the Allison 250 engines than any other engine. While the Allison 250 engine has widespread commercial use, the military's workload is declining. There were about 18,900 Allison 250 engines in the commercial market compared with only about 2,400 military engines as of 1997. Projected T63 workload at Corpus Christi Army Depot was expected to decline from 32,920 direct labor hours in 1993 to about 3,000 direct labor hours in 1997. Even though Corpus Christi had extensive excess engine repair capacity and repairing small quantities of T63 workload recovers some fixed overhead costs, continuing to maintain the T63 repair line in-house is probably not cost-effective.

In 2002 the Propulsion Directorate's Fuels Branch completed the first evaluation of fuel additives to mitigate soot particulate emissions from turbine engines. Airborne particles pose both health and environmental risks, and as such, the Environmental Protection Agency has a health-based regulation to control particulate emissions with diameters equal to or smaller than 2.5 m.

Directorate researchers tested 17 additives (commercial additives to reduce emissions in internal combustion engines, diesel cetane improvers, and experimental/proprietary additives) in a T63 helicopter engine. Directorate researchers analyzed engine exhaust using a suite of state-of-the-art instrumentation to characterize particulate number density (number of particles per cubic centimeter), size distribution, mass, and particulate chemical composition.

The detergent-type additive reduced particulate number density by 67%, resulting in a calculated particulate mass reduction of 53%. Further investigations into this and other additives of similar chemistry are ongoing in the T63 and in atmospheric combustors to help elucidate the mechanisms by which the additive reduces particulate emissions in the T63.

T63 Turboshaft

Allision Gas Turbine company


Max Shaft Output
319 ft-lbs torque/365 hp

Weight -
158 lbs
Compressor -
7 stage axial, 1 stage centrifugal
Turbine -
2 stage power turbine
2 stage gas producer turbine

Application -
@ 100% RPM
Shaft power output : 6016 RMP
Gas Producer Rotor: 50,970 RPM
Power Turbine Rotor: 33,290 RPM

Allison Engine Co., Inc., a division of General Motors Corp., was the OEM of the T63-A-720 engine. The Allison group was acquired by Rolls-Royce in the mid-1990s. Tr. at 139, 350. Accordingly, Rolls-Royce is in essence the OEM of the engine. The T63-A-720 engines to be overhauled under the Army's proposed 2001 sole-source contract to Rolls-Royce are used in the Army's OH-58 "Kiowa" helicopter. The Kiowa helicopter had been in service for approximately 30 years.Up until the mid-1990s, the Army had an "organic" (i.e., in-house) ability to overhaul the engines.

As part of its in-house ability, the Army maintained an "instruction manual describing the operations, procedures, and practices required to overhaul the engines." This instruction manual, called a "Depot Maintenance Work Requirement" (DMWR), also listed the required tooling and test equipment to perform the overhauls. Id. The Army maintained and updated the DMWR through amendments made by its own engineers, as well as through its receipt of commercial engine bulletins from the original equipment manufacturer (OEM) of the T63 engine. The DMWR was also used to competitively procure engine overhaul services from commercial vendors, with the last such contract being let in 1993.

The Army decided in the mid-1990s to phase out the Kiowa helicopter in 2004, and stopped maintaining its DMWR as of 1993. The last overhauls of the engines were performed in-house in 1997 using the DMWR and available updates. The agency stated that it needs to procure the engineering services from Rolls-Royce because the Army's DMWR was out of date, and it needs to procure the overhaul services from Rolls-Royce because the Army has divested itself of the tooling and equipment needed to overhaul the engines.

On January 13, 2001, the Army published a notice in the Commerce Business Daily (CBD) of its intention to award a sole-source contract to Rolls-Royce. The CBD referenced solicitation No. DAAH23-01-R-0067, and stated, among other things, that the contractor would be required to "furnish all depot-level labor, facilities, special tooling, test equipment, and materials for the maintenance, overhaul/repair modification" of up to 300 of the engines, and that "[t]he contractor will also upgrade Engine configuration to commercial and provide all technical data to identify the engineering changes."

Shortly after the CBD notice was published, Sabreliner and two other firms requested copies of the solicitation. The agency did not respond to the firms' requests, but rather, the contracting officer continued to meet with, and receive proposals from, Rolls-Royce with the intent of awarding Rolls-Royce a sole-source contract. After receiving approval to issue a letter contract to Rolls-Royce on May 4, the contracting officer states that "it was discovered that three sources had requested a copy of the solicitation based upon the synopsis," and that "[t]his was the first time that the Contracting Officer was made aware of these requests."

The contracting officer responded by providing each of the three firms, including Sabreliner, a letter stating that "a formal solicitation is not available," but providing each of the firms with a statement of work (SOW) setting forth the agency's needs. The letter and SOW were provided to each of the firms by facsimile transmission at approximately 1 p.m on May 10, with the letter informing the firms that "[a] Firm Fixed Price Proposal and supporting documentation as well as a Small Business Subcontracting Plan, if required, is due to this office [by] 10 May, 2001, 4:00 p.m."

Sabreliner filed a protest with the agency on May 10, complaining, among other things, that the 3 hours the agency provided Sabreliner to prepare its proposal was inadequate, and that the proposed sole-source improperly "bundled" the engineering and overhaul services. Sabreliner asserted that it is authorized, and has the ability, to overhaul the engines, and that because of this, it should be permitted to compete for those services.

The agency states that in an effort to resolve Sabreliner's agency-level protest, it contacted Sabreliner and asked whether the protest could be resolved by providing Saberliner with additional time to prepare its proposal. The agency states that it was informed by Sabreliner that "only a separation of the overhaul from the data requirements and the overhaul portion being solicited competitively would satisfy Sabreliner." The agency explains that it had another discussion with Sabreliner, and "agreed to further consult with the government technical personel and have a later conference with Sabreliner." The contracting officer states that after discussing the matter with the agency's technical personnel, she determined that the agreed upon conference with Sabreliner "would not be fruitful," and informed Sabreliner on June 7 that there would be no conference. Sabreliner filed its protest with our Office the following day.

Sabreliner protested the selection of Rolls-Royce for award of this sole-source contract on the grounds that the Army improperly determined that Rolls-Royce was the only responsible source capable of meeting the government's needs with regard to both the engineering and overhaul services. Sabreliner argues in the alternative that if the agency properly determined that only Rolls-Royce, as the OEM, is capable of performing the engineering services, the agency nevertheless lacks a reasonable basis for requiring that both the engineering and overhaul services be performed by Rolls-Royce, contending that if need be, the agency should procure the engineering services from Rolls-Royce on a sole-source basis, and then compete the overhaul services.

Sabreliner pursued its protest in part by arguing and submitting evidence of its ability to overhaul and upgrade the T63-A-720 military engines to a 250-C20B commercial configuration as indicated by the CBD and J&A. For example, Sabreliner provided evidence that it has performed a contract for the Department of the Navy for the overhaul and upgrade of two of its T63 engines to the 250-C20B commercial configuration, and it was agreed that one of the issues to be addressed at the hearing was Sabreliner's capabilities to overhaul and upgrade the T63 engines to the commercial configuration. Because the agency waited until the hearing to inform Sabreliner and our Office that the J&A was inaccurate in that the agency's needs were not for the overhaul and upgrade of its T63 engines to the 250-C20B commercial configuration, but rather, were for the upgrade and overhaul to the latest T63 configuration, Sabreliner has never been afforded any real opportunity to demonstrate its capabilities to meet the agency's actual needs.

The protest [B-288030; B-288030.2] to GAO was sustained on September 13, 2001. GAO recommended that the agency first reassess whether a sole-source contract with Rolls-Royce is necessary to meet its needs with regard to the engineering services. If the agency reasonably determined that the award of a contract on a sole-source basis to Rolls-Royce is necessary for the engineering services, the agency should execute a properly reasoned and accurate J&A for the sole-source award, and properly synopsize its requirement. In addition, if, upon further review, it is the agency's position that it could develop data in 8 to 10 months that would be sufficient to permit the overhaul services to be competed among commercial vendors, and that based upon current information the agency will require overhaul services for the next 19 years, GAO recommended that it develop the data sufficient to permit the overhaul services to be competed, and then competitively procure the overhaul services.

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Page last modified: 07-07-2011 02:37:52 ZULU