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Flight International's Canada special was released today. Our cover story is about Canada's military aircraft procurements and focuses on that nation's quest to replace its ageing fleet of 78 Boeing CF-18 Hornet fighters with the Lockheed Martin F-35 Joint Strike Fighter.

Read the full story here. You actually will have to register for access to read the whole thing, but it's free and takes less than five minutes.

In recent months, the Canadian government has been saying it will review the program and potentially run a formal competition if need be. Basically, the consensus amongst Canadian defense experts is that any contest will boil down to the F-35 and the F/A-18E/F Super Hornet.

Anyways, here are some extras that had to be cut from the feature due to space constraints.

The within visual range combat capabilities of fighter aircraft relative to each other anyways draws significant interest on here. So this is what Dan McWilliams, who flew the CF-18 Hornet for 10 years with the Canadian Forces, has to say about the F-35's close in within visual range combat capabilities. The caveat here is that he's basing his opinion on what a military F-35 test pilot said--basically that the jet flies like a clean C-model Hornet.

I would assume the test pilot was comparing close combat performance based on the upgraded F/A-18 engines (EPEs), which produce about 20% more thrust than the CF-18's engines (non-EPE). If so, performing like a clean legacy Hornet puts it in an elite class of fighter, with very good performance. How important this is depends again on the role and the requirements. Some contenders like the Rafale and the Typhoon may have better performance when clean, but they degrade when loaded up with external stores (more drag and weight). Super Hornets are bigger and heavier than legacy Hornets, but some engine upgrades may allow them to perform nearly as well (again, when not loaded with external stores).

There is always a debate about how important this close-in turning performance is. With advanced data links and good teamwork, it becomes less critical, because identification of threats and targeting can be done well before close-in performance becomes necessary. Weapons also make a difference. A good sensor/weapon combination can make turning less important, since it can be launched many degrees off boresight. Imagine, in the fantasy world of James Bond, the ability to launch a weapon at a threat in the rear quarter; turning would become far less important in that theoretical case! Helmet-mounted sights and AESA, paired with other types of sensor, can make a fighter able to launch at threats well off the nose.

Here are McWilliams' thoughts on just how robust an airframe is needed for operations in the Canadian Arctic:

The airframe does not need to be particularly robust for NORAD ops. Missions are quite benign in terms of G loading, and runways are runways. What could matter is how well does the airframe handle icing conditions in cloud. Prolonged flight in icing conditions is not permitted with a CF-18, due to danger of ice ingestion into the engines, causing damage to engine compressor blades. A question for the JSF is how robust is the aircraft skin, especially when dealing with icing and runway contaminants in winter conditions? The recent question of arrestor hook is also germane - sometimes we depended on the cable to stop us when runways were short and icy, which is not likely to change.

Range is one area where the CF-18 is not very good for NORAD missions. Many of the candidates go further and/or have more time on station, thus are better suited to NORAD, as are JSFs. Air refueling support is essential for most NORAD wartime scenarios, and even for some peacetime intercepts. When the Bears are well off shore (as the cruise missile carrier variants are usually), the CF-18 is quite limited in the amount of time it can escort or shadow them before having to turn back to base.

After yesterday's China Daily story quoting Xian Y-20 design chief Tang Jun (also spelled Tang Changhong) about the type's export potential, the Ministry of National Defence has published another China Daily story based on his comments. The exuberant headline says it all: "Confidence sky-high over jumbo cargo plane."

"The country's first jumbo airfreighter is set for take-off into official service, its chief designer said weeks after its successful maiden test flight," reports China Daily.

"When fitted with Chinese-designed and manufactured engines, the Yun-20, or Transport-20, will have a greater take-off weight, longer fuselage and carry more cargo."　

Tang is reported as saying that the type will enter service in 2017.  Tantalisingly, the report also notes this: "[The Y-20] is currently powered by four Russian-made engines, but these will ultimately be replaced by engines designed and made in China."

It will be interesting to see how long it takes Beijing to get an indigenous engine flying on the Y-20, and if the engine will be ready for the 2017 target.

The report also gave a few details about the Y-20's dimensions: 45m wingspan (vs. 51.74m for C-17) ,  MTOW of 200 tonnes (vs. 265 tonnes for C-17) , and "load-carrying capacity of 66 tons" (vs. 77.5 tonnes for C-17).

If these numbers are correct, there is a strong possibility the Y-20 (in its current state) is seriously under-powered compared with its US counterpart. Most pundits believe the Y-20 prototype is powered by the Soloviev D-30s used aboard Tupolev 154M airliner and the improved Il-76MD - an after burning version powers the MiG-31.  The D-30, however, produces maximum thrust of 23,150 lbf (103 kN), compared with the 40,440 lbf  (180kN) certified maximum performance of the Pratt & Whitney F117-PW-100 turbofan that powers the C-17.

For me, the most intriguing option for a future Y-20 power plant is a hypothetical military variant of the CJ-1000A, an indigenous power plant for the Comac C919 airliner that is being developed by AVIC Commercial Aircraft Engine.

In September 2011, Comac told Flightglobal that the high-bypass CJ-1000A will be capable of producing up to 44,000lb-thrust (196kN). This is considerably greater than the 28,000-30,000lb thrust of the C919's launch power plant, the CFM International Leap 1C. It also would exceed the F117's certificated maximum performance of 40,400lb.

Was there ever a YF-24? The US Air Force says no. "Our historians said there is no record of there ever having been a YF-24," says Lt Col Max Despain, an Air Force spokeswoman at the Pentagon. "Perhaps it's being mistaken for an X-24 which wasn't a fighter?"

That said, this old bio for a former test pilot, Colonel Joseph A. Lanni lists such an aircraft--which is curious. So there remains a small possibility a YF-24 might have been squirreled away somewhere out in the desert in Nevada. I say that because Lanni, according to his bio, commanded a classified flight test unit between July 1995 and June 1997.

While the entry in the bio might be a typo, it was certainly not the X-24 that Lanni flew. The Martin Marietta X-24A flew during 1963 to 1975, which was well before Lanni became an Air Force pilot. It's also not likely that Lanni flew the Northrop YF-23 either since he was assigned to Eglin AFB in Florida during the time those jets were flying.  

So, what exactly the YF-24 is or was is still kind of a mystery. Your guess is as good as mine.

But I did find this intriguing Boeing Multirole Fighter concept design called the Model-24F, which seems to have preceded the Joint Strike Fighter program. Certainly the design shares traits with earlier Boeing concepts from the Advanced Tactical Fighter program and with later efforts such as the ill-fated X-32 and more recent F/A-XX concepts the company has been showing-off.

From the specifications, it was clear that at the time the Model-24F was being examined, the USAF was looking for a much lighter and much faster aircraft than the current Lockheed Martin F-35. It's apparent from these diagrams that the Boeing Model-24F design was to be a much more slender aircraft than what eventually became the JSF.  It also looks like it was designed to be far more agile--it has provisions for two-dimensional thrust vectoring and some other interesting features. The design matches the Raptor's top speed of about Mach 2.2 though it doesn't cruise supersonically like the F-22.

Here is the full USAF report of the Model-24F.

GetTRDoc (1).pdf by

The US Air Force hopes to keep its fleet of Boeing F-15E Strike Eagle multirole fighters in service into the 2030s, but it has no definitive plan to eventually replace those aircraft.

Read the full article here

The Strike Eagle is arguably the best multirole combat aircraft in the USAF's inventory. No other fighter offers the range, payload or breadth or depth of capability as the F-15E. The Lockheed Martin F-22 Raptor was designed to replace the Boeing F-15C, but not the Strike Eagle. The Lockheed F-35, meanwhile, is designed to replace the Fairchild Republic A-10 and Lockheed F-16, but it does not have the range or payload to take on the Strike Eagle's role. At some point, the USAF will have to make a decision on what, if anything, will eventually fill the F-15E's mission space in the 2030s as those airframes inevitably wear out.

Industry sources are confident that a variant of the F-35 could one day replace the F-15E.  An extended range version of the F-35 can be built; it's already been studied. It would be particularly helpful if the Air Force Research Laboratory's Adaptive Engine Technology Development (AETD) program pays off with an engine that yields 35% or better fuel efficiency over the Pratt & Whitney F135. The same is true of a two-seat F-35 variant, industry sources say that it can be done--that is, if in fact, two-seats are needed. And there are options to increase the jet's payload. 

But analysts are less sure. They say that modifying the F-35 is going to require a lot of effort and it will be costly. The old Lockheed FB-22 concept that was based on the Raptor would have practically required a redesign of the entire aircraft (and there are questions about what kind of range the FB-22 could have yielded--the F-22's Achilles' heel is its range--only slightly better than an F-16). Another example is the Boeing F/A-18E/F, the Super Hornet is for all intents and purposes an entirely new airframe compared to the original A through D-model jets.

There could be a sixth-generation option--the USAF and US Navy have started looking at what an F-X and F/A-XX would look like. Or there could be other options like an unmanned aircraft tethered (line-of-sight data-links, possibly laser-based) to a manned platform such as a Long Range Strike Bomber (LRS-B). That would mitigate some of the comms issues inside an anti-access/area-denial environment. 

But any decision would have to be taken by the end of the decade at the very latest--it takes a very long time to develop and field a modern combat aircraft. However, given that there are so many competing resource priorities for the USAF, there must be serious consideration given to simply increasing the number of LRS-Bs to take over some of that mission space. It could be argued that if the LRS-B program were extended from 80-100 aircraft to a production run of 250-300 aircraft, one could recapitalize the entire USAF bomber fleet and forego an F-15E replacement.

There is, of course, a potential wild card. I suppose whatever the USAF is building out at Groom Lake could partially fill the deep interdiction role--if it exists and is designed as a penetrating strike/ISR platform. But as the Lexington Institute's Dan Goure points out, aircraft developed in the black world tend to be extremely high tech and extremely expensive boutique items. So, that's probably not a likely scenario.

In any case, if there is eventually a program to replace the Strike Eagle, it must be built in some numbers. It seems that every time the USAF embarks on a program, far fewer aircraft than expected hit the ramp at the end of the day (or two-and-a-half decades!). If the trend continues, the USAF's fleet of modern frontline combat aircraft will continue to shrink to potentially dangerous low levels, leaving a force of antiquated jets to face off against ever more capable foes.

Anyways, I'm off to Canada for the holiday season, so DEW Line posts will be sporadic (at best) until the New Year. So I'll leave you all this to ponder--it's an MIT Technology Review article on a potentially unjammable radar based on the quantum properties of photons.

Happy Holidays!

The US Air Force's new ultra-stealthy Long Range Strike-Bomber will be optionally manned when it enters service in the mid-2020s, the service says.

The aircraft will need a crew, particularly when operating inside a comms degraded/comms denied environment deep inside hostile airspace. Moreover, unmanned aircraft just don't have the reaction times and the on-site judgment offered by on-board human pilots.

But crews are mere humans, and as such need food, water, rest, latrines... Unmanned aircraft don't have such frailties, they have enormous persistence. The USAF is hoping to leverage the best of both worlds in the LRS-B.

My acquaintance USAF Lt Col Peter Garretson argues the case for an optionally manned LRS-B in an article he wrote for Armed Force Journal, edited by my former editor and friend Brad Peniston. Read it here.

The US Air Force's new Long Range Strike-Bomber (LRS-B) program is entirely classified. The USAF isn't just withholding technical data, the service won't even share programmatic details such as if there is a system program office in place or a competition or anything else. "Specific LRS programmatic details are protected with enhanced security measures," says Air Force spokeswoman Jennifer Cassidy.

Northrop Grumman Photo

All we know for sure is that there is some money allocated for the program in the budget--about $300 million in fiscal year 2013 and total of  $6.3 billion from fiscal years 2013 to 2017--and what few details the USAF is willing to release. We know that the new bomber will be a stealthy, optionally-manned, long-range penetrating strike aircraft that will be part of a "family of systems" from the service's budget documents. Those same documents say the service is aiming for a price tag of around $550 million per aircraft--and it wants the plane operational by the mid-2020s. Ultimately, the Air Force hopes to buy anywhere from 80 to 100 aircraft.

That's all pretty optimistic, of course... Delays and cost overruns tend to be almost inevitable when developing a sophisticated new weapons system--even if that system uses "mature technologies" as the Air Force says the LRS-B will. But with the US defense budget sure to come down over the next few years, it's not clear what the future holds for the new bomber.

But the LRS-B does enjoy high level support in the Pentagon and the Whitehouse (it was the only program that US President Barack Obama specifically referred to during the budget roll-out earlier in the year). But then there is the whole sequestration issue coming up in January, so we'll see what happens...

Kremlin Photo Tupolev Tu-160 Blackjack.

Meanwhile, Russia is also developing a new bomber called the PAK-DA. According to press reports in that country, it's being developed by Tupolev... Which makes sense--Tupolev did develop the Tu-95 Bear, Tu-16 Badger, Tu-22 Blinder, Tu-22M Backfire and finally the Tu-160 Blackjack.

There appears to have been a debate as to whether Russia actually needs a new bomber--though Russian policy-makers appear to have decided to go ahead with the project. Earlier in the year Russian deputy Prime Minister Dmitry Rogozin told Izvestia that bombers probably wouldn't remain a part of the Russian Federation's strategic nuclear deterrent in the future. "Look at the level of development of anti-aircraft and anti-missile defenses: all these planes will never get near their targets," he said.

But Rogozin appears to have been overruled by Russian President Vladimir Putin. "We have to develop work on the new PAK-DA long-range bomber aircraft for Long-Range Aviation. I know how expensive and complex this is. We have talked about this many times with ministers, and with the head of the General Staff. The task is not easy from a scientific-technical standpoint, but we need to start work," Putin said, according to RIA Novosti in June. The Russians, like the USAF, hope to have their new bomber operational by the mid-2020s.

A Xian H-6, photo by Aquatiger127, Wikimedia Commons

One country that doesn't appear to have any immediate interest in building a new strategic bomber is China... They have fairly recently modernized their Xian H-6 fleet to the new H-6K variant. The new variant entered service in 2009 apparently with updated avionics, engines and aircraft--though at the end of the day, it's still an antique Tu-16 Badger copy. The aircraft is also reportedly equipped with new cruise missiles, which could potentially threaten US aircraft carriers and outlying US territories and bases--in keeping with the anti-access/area denial strategy. But there doesn't appear to be another Chinese bomber project right now that's been observed, but who knows?

50 years ago today, the US Army received its first CH-47A Chinook tandem-rotor helicopter. It's probably not likely that anyone that day could have foreseen that exact same helicopter would not only be flying, but also receiving upgrades so that it can continue to fly for the foreseeable future. Moreover, it's entirely possible that the Chinook could still be flying for another 50 years...  I'd put money down on it.

Here is my retrospective on the Chinook.

Here is Flight's editorial from the 14 August issue.

Boeing's CH-47 Chinook might become the first rotorcraft to fly for a century. Its success is due to innovative design and prodigious power margins.

It is fast, agile and has outstanding high altitude performance. It can also be quickly and easily upgraded - and will continue to evolve for the foreseeable future.

But the Chinook's success and longevity also highlights a quandary in the helicopter design world.

Since the introduction of gas turbine engines, there had not been a real technological breakthrough until the advent of Sikorsky's X-2 compound helicopter prototype. But while the X-2 shattered speed records - thumbing its nose at retreating blade stall - it is unclear if it will ever find a buyer.

Nor is it clear if Eurocopter's X3 high-speed compound helicopter is on any better a footing.

Meanwhile, tilt-rotor technology increasingly looks to be an evolutionary dead end. The compromises to hover performances imposed by that design do not appear to be acceptable to most potential customers. Nor is the high price of such aircraft something many customers are willing to pay.

The bottom line is that while speed is always nice to have, the market does not appear to be willing to pay a premium for that added performance. This means that aircraft like the Chinook will probably soldier on decade after decade.

The United States doesn't have a monopoly (anymore) on developing fifth-generation fighters, Russia seems to be making good progress on its next-generation Sukhoi T-50 PAK-FA stealth fighter--a version of which will also serve with the Indian Air Force. PAK-FA apparently stands for Perspektivny Aviatsionny Kompleks-Frontovoy Aviatsii--if anyone cares. It is amazing that the Russians managed to preserve so many of the skill-sets needed to develop an advanced fighter aircraft (and other parts of the defense industrial base) even as their entire society basically disintegrated around them after the fall of the Soviet Union.

Sukhoi Photo

My colleague Valdimir Karnozov in Moscow is reporting that Sukhoi has started flight testing a new Active Electronically Scanned Array (AESA) radar on the third flying prototype for the PAK-FA. The Russian AESA, from what Sukhoi says, seems to feature most of the same modes that one might expect from a US-developed set. That includes simultaneous operations of air-to-air and air-to-surface modes among other features.  The Russians are also testing what they call "optical channels" on the aircraft--which sounds like it might be some sort of electro-optical or infrared camera system. I suspect something is being lost in the translation.

Read Valdimir's story here

Sukhoi Photo

Sukhoi is apparently gearing up to fly the fourth PAK-FA prototype in the near future. I will say that the PAK-FA, like a lot of Russian and Soviet aircraft that have come before it, is one sharp looking jet. But, up close, these aircraft don't have the fit and finish that one might find on a Western aircraft. While there remains little doubt that Sukhoi can design a fifth-generation fighter, whether they can manufacture one is yet to be proven. Extremely precise manufacturing is a key tenet of building a stealth aircraft... so we'll see.

Sukhoi Photo

Meanwhile, the Russians have not given up on fourth-generation fighters. The new Su-35 Flanker-E is scheduled to enter full production in 2013. It's already in limited production with six aircraft scheduled to be delivered to the Russian Federation Air Force this year. And, according the Russia's United Aircraft Corporation boss Mikhail Pogosyan, Russia will continue to build Su-35s alongside the T-50 for the export market.

Sukhoi Photo

They might also retrofit the PAK-FA AESA onto the Su-35... It currently has a passive electronically scanned array installed.

Sukhoi Photo

The Boeing CH-47 Chinook entered into service 50 years ago. Though its subsystems have evolved over the years, the basic design remains the same. Given the US Army's current plans, the venerable Chinook might well be the first 100 year rotorcraft design... I'm willing to bet there will be at least a few of these magnificent machines still flying in 2062. Possibly even some of the very same aircraft that are flying right now... After all, the very first Chinook ever built is still in service and has seen multiple tours in Afghanistan. It's likely that the Vertol--before Boeing bought the company in 1960--engineers who were developing this aircraft back in the late 1950s couldn't have imagined their creation still being in service 50 years--let alone 100 years-down the line.

Here is a video from earlier in the year--it shows off some of the awesome capabilities of this machine.

Yesterday, my friend and colleague Greg Waldron, our defense reporter for Asia, reported that Boeing has integrated a new version of the Joint Helmet-Mounted Cueing System (JHMCS) onto its F-15SE Silent Eagle demonstrator aircraft.  The new helmet is called the JHMCS II/h--and it is designed to be lighter and better balanced.

Read his story here

Boeing's Silent Eagle demonstrator-Boeing photo

"Both pilots who flew with the JHMCS II/h system immediately noticed that the helmet was more balanced and the smaller, lighter interface cable was less restrictive," says Greg Hardy, Boeing JHMCS program manager.

It took Boeing less than three months to integrate the helmet onto the aircraft.

The F-15E Strike Eagle is arguably the best multi-role fighter in the US Air Force's inventory. The Silent Eagle improves upon that by adding an active electronically scanned array (AESA) radar--specifically the Raytheon APG-63 (v) 3. It also has a decoupled cockpit design--modeled on the US Navy's Block II Super Hornet--that would allow the pilot and weapons systems officer to simultaneously conduct air-to-air and air-to-surface missions at their respective stations. It will also have a new large area display similar to what is currently installed in the Lockheed Martin F-35. Boeing also says that the aircraft will have a degree of frontal sector stealth--it has airframe modifications and conformal weapons bays which can be added or removed as needed to accomplish that (but if the CFTs on the F-15E are any indication, it'll be kind of a pain in the posterior for the maintainers).

South Korea is probably the last chance for Boeing to sell the F-15SE while going head to head with the F-35, says Richard Aboulafia of the Teal Group. "That's going to be intriguing to watch."

While Boeing has kept the USAF in the loop on developments on its international F-15E derivatives, the service hasn't committed to fielding any of those modifications just yet. But the USAF is making progress on adding a new Raytheon APG-82 AESA radar to its fleet of Strike Eagles. Since the aircraft will remain in service till at least 2025, it is likely there will a host of upgrades coming at some point.

Incidentally, a clean--with no conformal tanks mounted-- F-15E powered by twin Pratt and Whitney F100 PW-229 engines is a stellar  performer according to USAF and Boeing pilots who have flown in that configuration. One Boeing pilot says that with the 29, 100lbs 229 motors, the clean jet climbs like a rocket--potentially giving even the F-22 Raptor a run for its money. It will also easily cruise supersonically. "It's a monster," another pilot says.

But the USAF (or other air forces flying Strike Eagle derivatives) does not normally fly the F-15E in a clean configuration--it's a pain for the maintainers to constantly load and unload the CFTs. One also losses a good 10,000lbs in gas and a number of weapons stations when the CFTs are not loaded.

Given that the USAF's front line fighter force in 10 years is going to consist of only 185 Lockheed Martin F-22s and about 400 or so F-35As along with a fairly large number of aging F-16s and F-15s, it could be argued that the service should have considered buying some modernized fourth-generation machines--like the Block 60 F-16s or advanced F-15s derivatives--during the 1990s. But money was tight then as it is now.

The Navy seems to have done very well with the F/A-18E/F Super Hornet, however. Of course, hindsight is 20/20.