KC-46 Pegasus fueling an F-15

Aerial refueling is nothing new.

In theory, aerial refueling is a simple concept.  Take one, preferably large, aircraft with the ability to carry much fuel as possible.  Then modify that aircraft with some sort of umbilical that can connect to another aircraft while both are mid-air, allowing fuel to be transferred from the tanker aircraft to the other.  This allows the freshly refueled aircraft carry on with its mission when landing would not be possible or otherwise inconvenient.

The first successful aerial refueling happened almost 100 years ago, only a scant 19 years after the first powered flight.  The concept began more widespread military use in the early days of the Cold War following World War II.  Since then, the ability to provide in-air refueling has become a core capability for almost every modern major air force.

For the United States Airforce (USAF), aerial refueling has become a vital asset.  The United States military depends on its tanker fleet for "force projection".  Without it, getting needed bombers, fighters, and transports to a global "hotspot" would take days or weeks, instead of mere hours.  To classify tankers as "vital" is an understatement.

A KC-10 (left) is refueled by a KC-135 (right)
For years, the bulk of America's aerial refueling needs have been met by two aircraft, the KC-135 Stratotanker and the KC-10 Extender.  These aircraft share similar design concepts; take an existing airliner and outfit with refueling gear.  The most obvious modification being the refueling boom under each aircraft's tail.  Both aircraft are also equipped with a "probe-and-drogue" type system.

Both of these aircraft have acted as reliable workhorses for not only the USAF, but the entirety of American airpower, NATO, NORAD, and other allies.

Unfortunately, both of these aircraft are getting on in years and due for replacement.  The airliners that they are based on, Boeing 707 (KC-135) and McDonnell Douglas DC-10 (KC-10), have not been  manufactured for decades, making parts availability challenging and expensive.

In theory, finding a replacement for the two tankers should be easy, just replicate the design philosophy of the KC-10 and KC-135 with a newer airliner platform.  By rights, this should have been one of the simplest research and development tasks followed by a smooth procurement and implementation.

Instead, they got the unmitigated disaster of the KC-X program followed by the epic failure that is the KC-46 Pegasus.

Airbus A330 MRTT
Almost 20 years ago, the plan was for the USAF to adopt the Boeing 767 into a new tanker aircraft.  This became politically problematic, as decision to do so came without any sort of bidding process.  Worse still, the initial deal was to lease the aircraft from Boeing.  This was deemed fiscally irresponsible.  After investigation, it was found that the deal involved outright fraud, with several of those involved seeing actual prison time.  Naturally, this led to a complete reset of the tanker replacement program.

When KC-X program (re)started, Boeing was ready with is 767 derivative. Airbus, partnered with Northrop Grumman, put its A330 MRTT (Multi-Role-Tanker-Transport) on offer.  Despite being viewed as the underdog, Airbus's bid was selected.  Boeing, of course, protested the decision, resulting in yet another restart of the competition with rewritten requirements.   Northrop Grumman concluded that the specs were written in Boeing's favor and dropped out of the program, leaving Airbus to go it alone against Boeing.

Boeing's was ultimately selected, being seen as "very, very, very aggressive" in a fixed-price contract award that ensures extra costs will be paid for by Boeing.  One cannot stress enough how much financial stress this places Boeing if things do not go according to plan.

If they only knew...

"Okay Boomer"-View from the KC-10 Boom Operator's station.
With all the political maneuvering out of the way, the development of the aircraft that would become the KC-46 Pegasus should have been rather simple.  Take an existing airliner (767-200) and add the requisite equipment to enable it to transfer fuel.

Converting existing aircraft to tankers can be simple task.  "Probe and drogue" systems can be added to existing aircraft with relative ease.  Such is the case with Canada's own CC-150T Polaris, C-130 Hercules, or even the F/A-18E/F Super Hornet.

Unfortunately for the USAF, merely adding "probe-and-drogue" pods to an existing design is not enough.  While probe-and-drogue works fine for smaller aircraft, it transfers fuel too slowly for big transports and strategic bombers.  That is why the USAF prefers "flying boom" method.  This requires much more specialized equipment.  While more complicated than probe-and-drogue, flying boom tankers have been in use since the 50s'.

There was no need to reinvent the wheel...  Yet for some reason, they did.

Tankers like the KC-10 and KC-135 utilize a "boom operator" that sits in a station located at the ventral rear of the aircraft.  The "boomer" has an unobstructed view behind and below and is able to "fly" the boom to a receptacle located on the receiving aircraft.

For some reason, it was decided that the "Mark I Eyeball" was not sufficient enough for 21st Century tankers.  Instead the KC-46 utilizes a "fully digitalized" system that moves the boom operator station to the main deck.  Instead of merely looking out a window, the boom operator utilizes a remote viewing system (RVS) that uses cameras, video screens, and special goggles to project a three-dimensional image.  Kind of like a backup camera in a car mixed with a 3D movie.  Perhaps they took inspiration from a certain blockbuster...

Unfortunately, the KC-46's RVS just plain does not work as it should.  Under certain lighting conditions, the image can appear warped.  It is bad enough that it could potentially cause damage to other aircraft, possibly scraping off valuable stealth coating or even worse.  A complete redesign has been ordered that utilizes laser range-finders, color screens, and improved computing power.  This will take years to implement.

KC-46 refueling boom

While new technology can, and often does run into teething problems, there is less of an excuse for faulty hardware that has been perfected for over half-a-century.  Especially when that item is the entire raison d'├¬tre.  The KC-46's defining characteristic, its "flying boom", has also been found faulty.

The KC-46's boom has been described as "too stiff" for smaller aircraft (fighters), requiring the need for extra thrust to "push" against it, creating a flight hazard.  There is also an issue of "inadvertent boom loads" in which the boom operator may unintentionally place stress on the receiving aircraft without even knowing it.

Even something as basic as as the way the KC-46 secures cargo has been deemed a "Category I" deficiency.  The Pegasus has been indefinitely restricted from carrying cargo or passengers due to faulty cargo restraints that could lead to damage, injury, or death.

The KC-46 Pegasus has been restricted from day-to-day operations until this mess is all sorted.

But wait...  There's more.

I...  I got nothin.

For those of you keeping score, the KC-46 is a multi-role tanker transport (MRTT) that not only poses a risk to the aircraft it refuels, but the personnel inside it.  If that was not enough, the KC-46 could potentially be a danger before it even leaves the ground.  

The KC-46 leaks fuel...

Not in the cool way that the SR-71 did in which there simply no sealants that can withstand Mach 3 heat, either.  The KC-46 leaks fuel between its redundant fuel protection layers.

All of these issues will take years to fix, not to mention millions of dollars.  Unfortunately for Boeing, it is on the hook for the millions (possibly billions) of dollars.  This is a bit of a problem right now as they are still reeling from the 737 MAX (Did I mention that the KC-46 uses the same MCAS system?).  Boeing is also reeling from the Coronavirus pandemic, as air travel comes to a near halt seemingly overnight.  Do not be surprised if Boeing looks for some concessions from the government for its $3 billion losses involved in the KC-46.

CC-150 Polaris

So what does all this have to do with Canada?

For one, the KC-46 is an obvious candidate to replace Canada's CC-150 Polaris.  Given the current state of Canadian defence procurement, that will not be an issue for years to come, possibly not until the 2030s.  This, despite a replacement being needed sooner rather than later.

At the very least, the decision would have to come after the results of the FFCP to ensure compatibility to our new fighters.  Selection the the F-35A would require a tanker with flying boom capability.  Both the Saab Gripen and Boeing Super Hornet use the simpler probe-and-drogue system used by the CC-150, making its replacement less of a pressing issue.

In the shorter term, the failure of the KC-46 has caused a shortage of refueling capability for not only the USAF, but NATO and NORAD as a whole.  In an alternate timeline in which Canada sole-sourced the F-35 as initially planned, Canada would depend on the USAF and private aerial tanker firms...  The same firms the USAF is now considering to fulfill the capability gap caused by a faulty KC-46 fleet.  This would leave the RCAF completely beholden to others for a core capability that is now in much higher demand.

F-35A aerial refueling
As Canada mulls over which fighter to replace the CF-18, it must acknowledge the challenge in integrating that fighter into our existing infrastructure.  Oddly enough, the failure of a Boeing product (the KC-46) poses serious ramifications for a Lockheed Martin product.  Of the aircraft under consideration, only the F-35A is incompatible with Canada's existing aerial refueling infrastructure.  Its selection would result in the immediate need to replace our existing tanker fleet at the cost of billions...  In which the KC-46 would be a likely option.  It would also require the short term use of a USAF tanker fleet and private tankers that have become stretched thin thanks to the deficiencies of the KC-46.  It is a good thing the USA is so willing to share when times get tough.

It is almost poetic that both the F-35 and KC-46 are linked together.  Both projects have been deeply mired and controversy.  Cost overruns, missed milestones, and seemingly endless bugs seem to be the norm when it comes American military product development.  At least the JSF program could be excused somewhat thanks to its ambition.  After all, one could not expect developing a fighter to be so many things to so many people to be an easy task.

The KC-46 Pegasus, on the other hand, should have been an easy slam dunk.  It has instead become a comedy of errors.  Somehow, Boeing managed to mess up something that it damn near perfected almost 70 years ago.  Then again, Boeing seems to be doing that a lot lately.


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