Here's a couple of articles I read on Boeing news about the B-52 the the JSF.
Boeing Pushing Engine Swap For '100-Year' Bomber
Momentum is building behind a propulsion upgrade of the 1960s-vintage, nuclear-armed Boeing B-52H Stratofortress, with Boeing proposing an eight-for-eight swap for engines designed to power regional jets in the 17,000-19,000 lb.-thrust range.
In the mid-2000s, the U.S. Air Force was tinkering with four engine options to replace the strategic bomber's aging Pratt & Whitney TF33s using Boeing 757 powerplants, the Rolls-Royce RB211 and Pratt PW2040 series. But that configuration would have taken too long and cost too much because of significant airflow changes, so the all wing-mounted weapons would need to be requalified for flight. Instead, Boeing is touting an eight-engine program that "avoids $10 billion" in operating, maintenance and sustainment costs compared to keeping the TF33 for the B-52's remaining 20-30 years of service life while extending unrefueled range by 40%.
Having lost the $80 billion Long-Range Strike Bomber contract to Northrop Grumman for 100 next-generation B-21 Raiders, the up-front investment required for a re-engining program would likely extend Boeing's B-52 business by another 20 or 30 years. Boeing delivered 102 of the newest H-models to Strategic Air Command from 1961-62 and they are capable of flying beyond 2060 based on 80,000 hr. of structural service life.
The Stratofortress has been a symbol of America's nuclear might since entering service in 1955, but more recently a symbol of decay. Three generations of airmen have already flown the B-52H, with President-elect Donald Trump pointing out during his election run that today's pilots are flying the same bomber as their grandfathers. Trump held up the B-52 as an example of the U.S. nuclear arsenal aging out as Russia and China race to modernize.
Adam Lowther, director of the School of Advanced Nuclear Deterrence Studies, echoed those concerns at a recent Heritage Foundation forum in Washington, saying Russia has already improved the propulsion systems and radars of its Tupolev Tu-95 "Bear" and Tu-160 "Blackjack" bombers' and introduced the Kh-102 cruise missile that can strike central America without leaving Russian airspace. "It's not just Alaska, and it's a very difficult missile to detect," he says.
Every heavy bomber program since the 1970s including the Rockwell B-1 and Northrop B-2 has been unable to fully supplant the B-52, and there are still no firm plans to retire the remaining 76 aircraft, even after Northrop's B-21 enters serial production in the 2020s.
In an interview, Boeing B-52 program executives Scot Oathout and Jim Kroening said the fleet remains in good health structurally and the avionics and weapons upgrades being delivered will keep the bomber viable for decades to come. They say the B-52 will remain operationally relevant alongside the B-21.
"It's a big, flexible truck," Oathout says. "Our Air Force is going to need a big, flexible truck for many, many years to come."
There have been several proposals to re-engine the B-52, but all were scrapped due to the technical challenge and cost. The most recent examination began in 2014 when the Air Force sought information on potential replacements for the 17,000-lb.-thrust TF33 that provides 10-25% less fuel consumption and at least 15-25 years of use between depot overhauls.
Former 8th Air Force bomber chief Maj. Gen. Richard Clark said in October that an engine replacement program is "critical" if the B-52 is to remain in service because it affords greater range, payload and electrical power while lowering operating and support costs. "I think it could really provide a good return on investment if we found a way to fund it," he says.
Boeing says using eight medium-thrust engines instead of four 757-class propulsors is a more "technically feasible, lower-risk approach." The company would not specify which engines were being considered because of the competitive nature of the program. It says each major manufacturer has an in-production engine to offer.
Proposed upgrade
Pratt has proposed a performance and reliability upgrade to the TF33, but it might otherwise offer a PurePower PW1000G series geared turbofan, which powers the Embraer E-Jet, Bombardier CSeries and Mitsubishi Regional Jet. GE Aviation's 18,000-lb.-thrust CF34-10A has entered service on the Chinese Comac ARJ21 regional jet and could be offered instead of the higher-power CFM International CFM56, which was used to re-engine the Boeing KC-135 Stratotanker but is not suitable for the bomber.
The firm could propose a high-power version of the GE Passport, developed with Safran for the Bombardier Global 7000/8000-series business jets. Rolls-Royce could propose the BR725, a 15,000-17,000-lb.-thust-class engine that powers Gulfstream's G650.
"We're really looking for that proven, technically feasible, low-risk engine with a lot of fuel efficiency," Oathout says. "The regional jet engines fit perfectly in terms of diameter, weight and thrust."
We've calculated over $10 billion in cost avoidance" over and above the cost of the re-engining, Kroening adds. "From a hydrocarbon perspective, it's about 2-3% of emissions relative to the current TF-33. The noise reduction is also significant."
In terms of avionics and weapons, the B-52 is slowly but surely being brought into the digital age. The Combat Network Communications Technology (Conect) upgrade achieved initial operational capability earlier this year with the first dozen modified aircraft now returned to service. Boeing is working on the second tranche of Conect kits, which are installed during depot maintenance at Tinker AFB in Oklahoma. It is the most significant computing upgrade in the aircraft's storied history, with the five modernized crew stations now connected to via a gigabit ethernet cable to a centralized computer with new processors, color liquid crystal displays, modems and radios for line-of-sight and beyond-line-of-sight information exchanges. A Link 16 datalink will provide "latency-free, real-time" communications with other U.S. and allied aircraft operating together in training exercises and war.
New conops
These types of networking upgrades are enabling new concepts of operation for the B-52 in conventional and nuclear war. The Air Force has begun stationing B-52s in the Middle East to conduct strikes against the Islamic State terrorist group in Iraq and Syria as well as provide close air support for allied troops on the ground. In the past, strike coordinates have been provided by voice radio and entered manually, or "fat fingering," into the bomb navigation system. Now that process is automatic.
The B-52 can carry 70,000 lb. (32 tons) of ordnance, most of which was freefall or "dumb" bombs in the past. The 1760 interface upgrade allows it to carry smart munitions, including precision-guided Boeing Joint Direct Attack Munitions (JDAMs), extended-range Lockheed Martin Joint Air-to-Surface Standoff Missiles (Jassms) and Raytheon Miniature Air-Launched Decoy/Jammers (MALDs) on its wings. The bomber retains its ability to carry strategic nuclear and non-nuclear AGM-86 Air-Launched Cruise Missiles (ALCMs).
Boeing has also begun upgrading spare Common Strategic Rotary Launchers to carry smart munitions internally, with six conventional "CRLs" already delivered. Boeing has begun full-rate production of the first increment, which allows each B-52 to carry as many as eight satellite-guided, 2,000-lb. JDAMs internally. The second increment, due in 2017, is an interim capability that supports a limited number of internal Jassms and MALDs due to electrical power limitation. "That's in development and is going through test right now," Oathout says. Full capability will be provided in 2018 when the aircraft's electrical power system is modified to support a full complement of Jassms and MALDs: eight carried internally and six per wing pylon.
Boeing says the first unpowered jettison of a JASSM from the rotary launcher occurred on July 28. The first MALD drop took place on Nov. 9, with both weapons showing good clearance through the bomb bay doors. The company will eventually retrofit all rotary launchers and aircraft to a common configuration.
The Air Force also is finalizing an acquisition strategy to replace the B-52's outdated and unreliable APQ-166 strategic radar. It has not settled on a mechanically steered or electronically scanned array, but any such an upgrade will vastly improve the aircraft's targeting ability both for air-to-ground and likely air-to-air modes. Radar suppliers have been providing information to the program office at Wright-Patterson AFB in Ohio ahead of a competitive tender funded for fiscal 2017.
The B-52 has been selected as the initial carrier of the Air Force's next strategic cruise missile, the Long-Range Standoff Weapon (LRSO). That ALCM replacement will also arm the B-2 and B-21. A competition to build the classified next-generation nuclear missile was launched in July and the B-52 will support flight testing. Boeing already is engaged with the LRSO program office at Eglin AFB in Florida to ensure a smooth flight test program.
"The weapon side is in competition, but the B-52 is the carrier platform for that weapon," the company says.
What's Left To Fix On Lockheed Martin's F-35?
2016 was a milestone year for Lockheed Martin's F-35, marking the aircraft's first international deployment as well as the U.S. Air Force's decision to declare its first squadron ready for war. Meanwhile, the cost per aircraft continues to come down year after year, and the Pentagon expects the price tag to drop significantly in the near future.
But 2016 was not without setbacks for the controversial program. After failing to come to an agreement with Lockheed on the long-awaited ninth batch of aircraft, the government in a rare move unilaterally issued a contract valued at $6.1 billion for 57 jets. The two parties are still working on a handshake agreement for Lot 10, which they had hoped to reach this fall. Meanwhile, although many of the international partners will move forward with a three-year bulk purchase of the aircraft starting in 2018, the U.S. military will not join in.
At the same time, the program still faces a host of technological challenges. The latest version of the aircraft's internal logistics system is delayed by several months, and operational test pilots are still seeing stability issues with the final warfighting software. The Joint Program Office (JPO) has resolved a quality issue with the avionics cooling lines that temporarily grounded 15 operational aircraft, but Lockheed is now racing to fix the 42 in-production aircraft that were affected. Further, the services are still dealing with fallout from two aircraft fires this year, and adjusting to technical issues discovered during recent testing.
Designing the world's most advanced fighter does not come cheap. The JPO is racing to finish the F-35's development phase--already at $14 billion since the 2011 program restructuring--but the Pentagon is preparing for a delay of up to seven months past the planned completion date and projecting additional cost growth of $530 million. And the $14 billion is only a fraction of the full bill to develop the aircraft. A July 2016 report from the Congressional Research Service pegged the research and development cost at $59.2 billion in fiscal 2012 dollars since the program's inception.
Here's a guide to the remaining challenges in Lockheed's F-35 program:
* Stalled contract negotiations
After 14 months of negotiating Low-Rate Initial Production (LRIP) lots 9 and 10, the government unilaterally issued Lockheed a contract for the ninth batch of F-35s. The decision to definitize the contract without first securing an agreement from Lockheed is an exceptional move rarely seen in Pentagon contracting actions, but may set a new precedent.
"I think the unilateral action came as a result of what had become a very, very prolonged period of negotiation, and it was the feeling where there just wasn't any more progress to be made," said Air Force Secretary Deborah Lee James during a Dec. 19 event in Washington. "That's a fairly unusual thing, it's not done all that much, so I wouldn't say that it might be more or less in the future, I think it really depends, and it was a unique set of circumstances in this particular case."
The government could move forward with a similar unilateral action on the anticipated Lot 10 contract, JPO Chief Lt. Gen. Christopher Bogdan acknowledged during a Dec. 19 media briefing. However, Bogdan said he hopes the two parties can come to a mutual agreement this time around.
The good news is the Lot 9 contract represents an overall drop in the average unit price of the aircraft, Bogdan stressed. Including the engine and Lockheed's fee, an Air Force F-35A now goes for $102.1 million, a 5.5% drop from Lot 8; a U.S. Marine Corps F-35B is down to $131.6 million, a 1.8% reduction; while a U.S. Navy F-35 is up to $132.2 million, a 2.5% increase, due to a decrease in Navy procurement quantities.
* No block buy for the U.S. services
As has long been expected, most of the international F-35 partners will move forward with a three-year bulk purchase, or "block buy," of aircraft in Lots 12, 13 and 14 beginning in 2018, Bogdan said. As recently as September, Bogdan expressed confidence that the U.S. services would join in the block buy in its second year. However, Bogdan said Dec. 19 that the JPO made a "strategic communication mistake" in characterizing the services' plan as a block buy, explaining that the U.S. will instead contribute money to buy long-lead parts in bulk during all three of those years.
The services have already budgeted for the additional funding, called an "economic order quantity" (EOQ), in their fiscal 2018 budget blueprints, but must ask Congress to authorize the transactions each year, Bogdan said.
The block buy will cover 451 aircraft and save about $2 billion altogether, Bogdan said.
* ALIS delays
Lockheed had hoped to deliver the latest version of the F-35's critical logistics system, the Autonomic Logistics Information System (ALIS), by the end of November. But now that date has been delayed yet again to February or March due to challenges with integrating the Pratt & Whitney F135 engine into the system, Bogdan said.
An internal diagnostic system that tracks each part of each plane worldwide, ALIS is crucial to efficiently maintaining and managing the fleet. The most updated version, ALIS 2.0.2, is planned to automatically include maintenance data from each aircraft's engine. This will ease a burden on maintainers, who currently have to get that data transferred manually from Pratt specialists, who first pull that information off the aircraft.
"This is a big deal for the maintainers because they don't have to do two steps to maintain the airplane, they can just do one," Bogdan said.
However, this capability will not be delivered to the warfighter for a few more months because of software difficulties in migrating Lockheed and Pratt data at the supply chain level, Bogdan explained.
The F-35 can still fly without the latest version of ALIS--even into combat. ALIS is a ground-based system that provides sustainment and support, but not combat capabilities, Lockheed has stressed.
* Ongoing software challenges
The JPO and Lockheed spent months in 2016 resolving a bug with the F-35's interim software load, Block 3i, that caused the aircraft's system to stall out mid-flight and have to be re-booted. Now the test team is seeing the same problem with the fighter's final warfighting software, Block 3F, which will enable the full-up aircraft to deploy critical weapons.
Although the operational aircraft outfitted with the fixed 3i software are seeing shutdown events, or glitches, only every 15 to 20 hr., the test aircraft are experiencing the problem after less than 10 hr., Bogdan said. This "choking effect" is caused, in essence, by a timing misalignment between the software of the aircraft's sensors and the software of its main computers.
These glitches do not cause the aircraft to fall out of the sky, Bogdan stressed, as most of the systems on the F-35 are "triple redundant." Instead, the pilot must re-cycle the individual systems until they begin working again.
This kind of problem happens "all the time" with any software-intensive aircraft, Bogdan emphasized.
"That's why you flight test, that's why you integrate software, that's why you lab test, to get it better," Bogdan said. "So the fact that 3F has started off poorly doesn't mean it's going to end up poorly, it just means it started off about where 3i and 2B were. We will get it better as we move along."
* Challenges with weapons integration
Weapons integration, including external weapons such as the short-range air-to-air AIM-9X Sidewinder missile, is central to the final Block 3F software load. But the program is running into challenges with integrating the AIM-9X, with recent testing revealing "load exceedances," or excess stress on the F-35C variant's wing structure during landings or certain maneuvers.
This is a serious issue, Bogdan acknowledged, but it is being resolved. The JPO has engineered and ground-tested a fix, which involves beefing up the structure on the inside portion of the wing, and will flight test the solution in January, he said.
Retrofitting the fix onto the aircraft is "simple," Bogdan said, because the outer wing of the C variant comes off "like a piece of Lego." This makes it relatively easy for maintainers to remove the faulty portion of the wing and install a new part.
"The point here is you don't have to do it on the airplane," Bogdan said.
* Putting out fires
The danger with beginning to buy and use an aircraft as it is still being developed--so-called "concurrency"--is that unexpected problems can crop up during operations. The JPO is still dealing with fallout from two operational aircraft fires this year, as well as an isolated quality escape system issue with the fighter's avionics cooling lines that grounded 15 F-35As this fall.
The most recent mishap occurred Oct. 27 when a fire broke out on a Marine Corps F-35B during a training flight at Marine Corps Air Station Beaufort in South Carolina. The root cause of the fire was a loose bracket designed to hold the electrical wires in the bay, Bogdan said. As a result of that loose bracket, the electrical wires began to chafe, and set off the spark that caused the fire. The incident was reportedly a Class A mishap, which involves damage of more than $2 million.
The JPO has known about this potential problem for a while now, and is currently retrofitting the fleet with a new, redesigned bracket, Bogdan said. Because not all B-model aircraft have been modified with the fix, pilots are flying with increased levels of risk, he acknowledged.
"Yes there are acknowledged risks," Bogdan said. "Until you fix that airplane, every airplane in the B model that doesn't have that bracket is going to have to be inspected and hopefully that bracket remains in place when it is flown."
Just a month earlier, an F-35A also caught fire as it was preparing for a training mission at Mountain Home Air Force Base, Idaho. The fire was quickly extinguished and no serious injuries occurred. The service is still investigating the root cause of the incident, but initial assessments point to a tailpipe fire due to strong tailwinds as the engine was starting, Aviation Week reported at the time.
Meanwhile, all 15 F-35As that were grounded in September due to loose insulation discovered in the wing fuel tanks have successfully returned to the skies. However, Lockheed is still fixing the 42 in-production aircraft that were impacted by the problem, an effort that has slowed down progress on the production line. The company had planned to deliver 53 aircraft this year, but will deliver just 45 as a result of this delay, Bogdan said. Production will catch up to planned contract delivery dates by August of 2017, he noted.
* Discoveries during at-sea testing
Finally, the program also is making adjustments due to discoveries during several recent periods of at-sea testing of the F-35B and F-35C variants, Bogdan said. Marine Corps and Navy operators still are experiencing problems with the helmet during night flights in which the symbols on the screen are too bright and can blind the pilot. The JPO does not yet have a permanent fix to the issue, and in may need to make some "operational changes" in the short term while pilots wait for a long-term solution.
The JPO also is working through a problem with the Navy F-35C variant in which the aircraft's nose appears to bounce up and down as it catapults off the aircraft carrier. This is primarily because the mechanism in the nose gear is not "damping out" the oscillations from the cable release quickly enough, Bogdan explained. This problem only occurs with aircraft at very light takeoff weights, he stressed.
