B-52 Stratofortress Re-Engine - 2014
In 2014 the Air Force reviewed industry studies of fitting its 50-year-old Boeing B-52 bombers with new commercial-derivative engines, according to Lt. Gen. Stephen Wilson, commander of the service’s Global Strike Command. Wilson said 09 October 2014 at a Washington meeting, the Air Force assessed that the change would result in a net cost savings over the remaining life of the B-52s, which were expected to fly until 2040.
Wilson did not identify the contractor that made the proposal or whether more than one company was involved. However, an industry source confirme to Bill Sweetman, writing for Aerospace Daily & Defense Report, that Boeing had presented a “concept brief” and that General Electric has looked at fitting the bomber with eight CF34-10 engines. Pratt & Whitney also was exploring options.
Fitting new engines would sharply reduce the bombers’ fuel burn the need for tanker support. Moreover, under current commercial standards the new engines would not have to be removed for routine maintenance over the lifetime of the aircraft.
Global Strike Command and Air Force Materiel command are examining the proposal. The main obstacles to a re-engining program could concern budgets and regulations. Airline operating experience would have to be used to support military airworthiness requirements, and the proposal rested on recovering an early investment through lower operating costs. Commanders have budgetary discretion to spend money against future energy savings when they modernize bases and other facilities, but not to modify aircraft.
This represented at least the third attempt to re-engine the B-52, which was powered by eight TF33 engines similar to those used on the Boeing 707. Pratt & Whitney studied the idea in 1982, with four PW2000-series engines. In 1996 Boeing and Rolls-Royce jointly proposed to fit B-52s with four RB211-535s, with the government leasing the engines. The first plan was not taken up because all B-52s were to be replaced by B-1s and B-2s by the late 1990s, and the second failed because of resistance to leasing combat assets and a flawed economic assessment by the Air Force.
According to a 2004 Defense Science Board report, the USAF failed to take the cost of air refueling into account. At that time, tanker-delivered fuel cost $17.50 per gallon, 14 times the cost of fuel on the ground. The DSB task force “unanimously recommend[ed] the Air Force proceed with B-52H re-engining without delay,” but no action was taken.
GE’s eight-CF34-10 option could deliver more thrust than the current engines (variants are rated at 17,640-20,360-lb. thrust) and would avoid engine-out handling issues. Pratt & Whitney announced in May that it was launching the PW1135G-JM, aimed initially at the A321neo and rated at a 35,000-lb. thrust class, slightly more than two TF33s. The new engines would deliver an even greater performance and efficiency improvement than the engines proposed in 1996. The RB211-535 has been out of production since the end of the Boeing 757 line in 2004, and the last F117s (military PW2000s) are being delivered with the final C-17s, so neither engine was a strong candidate.
The USAF was examining 'creative concepts' under which it could re-engine its fleet of 74 ever evolving B-52H Stratofortresses. With the bombers remaining in front-line service until at least 2040, and considering that flying with eight 1960s vintage TF33 engines was far from fuel efficient (burning 3k gallons an hour), re-engined B-52s should make great financial sense.
Defensenews.com quoted Lt. Gen Mike Holmes, deputy chief of staff for Strategic Plans and Requirements, telling reporters at an 06 February 2015 event: "To go out and buy new engines for the B-52, you'd have a really hard time fitting that into our program, but that's why we're interested in a public-private partnership, which would be a different way to amortize those engines over time and pay for them in the savings that they actually generate, instead of paying for them out of savings that you hope for.... The idea is in a public-private partnership, somebody funds the engine and then we pay them back over time out of the fuel savings, which are generated out of the new engines. Our government has a way to do that with facilities. We don't have a way to do that with airplanes, and we are exploring whether there are alternative ways that would let us do that... Look at what the airline industry is doing — they're all re-engining. Why? Because it saves you a lot of money. If there is a commercially available engine which can give a 25-30 percent increase in either range or loiter, you have my attention."
The Air Force has multiple legacy aircraft that would benefit from capital improvements to improve mission capability and reduce lifecycle costs. However, it was difficult to budget for all capital improvements when such projects commonly only realize savings over multiple decades. It was particularly challenging to budget for capital improvements in times of government austerity, such as that imposed by the current sequester. Financing of capital improvements was generally not favored in DoD acquisitions, because it was perceived as a financial risk and financing usually costs more than an outright purchase of equipment and services. So, even in circumstances where financing will result in a net savings to the Air Force over time, it was difficult to meet all regulatory requirements for financing in favor of direct procurement. The result was a general inability to secure funds to execute numerous cost-saving measures.
The B-52 provides a typical example of the challenges of financing capital improvements for a major weapon system. For nearly 20 years, numerous organizations have studied the cost-effectiveness of replacing the B-52’s engines. The current engines have been in use since the 1960’s, whereas modern commercially-available engines would result in a $100+ million reduction in sustainment costs and a 25+% improvement in fuel efficiency – not to mention providing significant improvements to mission capabilities. However, the cost savings would only achieve a financial payback in ~20 years. So, it was difficult to justify the upfront expense relative to other immediate priorities. If this and other similar long-term investments are to be realized, a means of financing the investments must be identified.
Using the B-52 re-engining effort as a model for other potential future efforts, the Air Force Office of Transformational Innovation was collaborating with Air Force Global Strike Command (AFGSC), the Air Force Program Executive Office for Fighter/Bomber (PEO-F/B), the Office of the Assistant Secretary of the Air Force (Installations, Environment & Energy), and others to assess financing options to replace engines on the B-52 fleet. Part of this effort includes navigating more than a dozen studies over the last 20 years that offer conflicting assumptions and results to establish a consensus business case analysis that will form the basis for future acquisition decisions. In parallel, current acquisition authorities and regulatory restrictions are being explored to identify permissible business arrangements that could lead to an affirmative decision to finance B-52 re-engining. Of particular interest are the use of operating leases and Energy Savings Performance Contracts (ESPCs) as general constructs to reach a financing solution, though it was understood that additional authorities may be necessary to practically implement either such construct. Other acquisition strategies are also under consideration to include all activities that must occur to integrate new engines on the B-52 airframe.
|
NEWSLETTER
|
| Join the GlobalSecurity.org mailing list |
|
|
|
