Throughout the years, Boeing has made some of the best military transport aircraft in history. Among them is the Boeing C-40 Clipper, currently used by the USAF, USN and even the USMC!
To date, 28 Boeing C-40s have been built (with only the US Navy C-40s being referred to as “Clippers”) and all have been used for over a year by their respective militaries.
Pre-Boeing C-40
Throughout the Cold War, Boeing and McDonnell Douglas had consistently made “flying offices” for the US military. This was usually done through a militarized variant of one of their civilian airliners.
For the US Navy, McDonnell Douglas had used their DC-9 short-haul airliner. This aircraft was designated as the McDonnel Douglas C-9 Skytrain II (in reference to the Douglas C-47 Skytrain used in WWII).
The US Marine Corps had also used the C-9 Skytrain II, using them in tandem with the US Navy. Similarly to the US Navy, the USMC used the C-9 to transport sailors/soldiers cross-country as well as high ranking officers to the front.
For the USAF, they had chosen to use the much larger C-137 for a “flying office” and the C-130 Hercules as a troop transport. Two C-137s would also go on to serve as VC-137s, otherwise known as Air Force One.
The Air National Guard (USAF reserve) similarly used three Boeing C-22s (militarized Boeing 727-300) as both personnel transport and as so-called “flying offices”.
In the late 1990’s, these aircraft were all well over 30 years old, and were becoming too expensive to operate and maintain. As such, they were all (independently) searching for a new replacement aircraft.
Development
The aviation community was well aware of this, and were all independently contacted about a possible replacement. However, Boeing seemed to be the only company with real-life examples of their aircraft.
Boeing offered the US Navy and USAF several options, including a new variant of the 737-700 (later known as the 737-700C) as well as a smaller 747. Other options included militarized variants of the 757 and 767.
The US Navy and USAF initially rejected the 747 and 757, mostly because they were too large for the role they needed to do. Upon further examination, the 767 was also rejected for the same reasons.
However, the USAF in particular wasn’t set on the 737-700C. This was probably due to the 1996 Croatia USAF CT-43 crash still being relatively fresh in the minds of the USAF.
The US Navy was set on the 737-700C, although, wanted several design changes in order to support the C-40’s intended role. This saw the fuselage remain the same, but have the wings and landing gear of the heavier 737-800.
Eventually, the USAF set its sights on the 737-300, but this was through the 737-700 Boeing Business Jet (BBJ). This also saw similar modifications, hence the common military designation.
Service
Following this, Boeing began to test the aircraft for itself, conducting a series of test flights, starting in April 2000. Once these had been completed, the first Boeing C-40 was delivered to the US Navy in April 2001.
The C-40s were delivered to the US Navy Reserve, where they were designated “Clipper” in reference to the Boeing 314 Clipper, which served with the US Navy during WWII.
Since the US Navy Reserve’s inception (or at least since the end of WWII), the US Navy Reserve operates all of the US Navy’s medium and heavy airlift operations. This includes their cargo operations as well.
The USAF’s 737-700 BBJs were designated as the Boeing C-40B, however, they have no official name. The Boeing C-40B was first delivered to the 89th Airlift Wing in December 2002.
In October 2002, the Air National Guard (USAF reserve) and National Guard Bureau announced that they’d be acquiring troop transport variants of the Boeing C-40, these were designated as the Boeing C-40C.
Initially, the USMC had not approached aircraft manufacturers for a new aircraft, instead intending to see what the USAF and USN would acquire. With them both acquiring the Boeing C-40 Clipper, the decision was clear.
In December 2018, the USMC made it clear that they intended to purchase two C-40As for the same purpose as the Skytrain fleet. The USMC Skytrains were subsequently retired, and C-40As have been entered into service in 2020.
Variants
Due to being operated by three different military branches, it’s only fair to assume that there would be several different variants of the aircraft.
C-40A
Of the three Boeing C-40 Clipper variants, the C-40A is the most common, with seventeen having been built. 15 of these aircraft are in service with the US Navy Reserve, whilst the rest are in service with the USMC.
The USN’s C-40s are certified to carry both cargo and passengers, as well as carrying both (known as a “combi”). Many of the former C-9 Skytrain crews retrained to fly the 737-derived C-40.
Due to the US Navy and US Marine Corps being very closely linked, the USMC also operates two C-40As. Prior to this, and after retiring their C-9 fleet in 2017, USMC crews worked on US Navy Clippers.
Upon Boeing delivering the USMC’s two C-40As, the USMC crews worked once again on their own aircraft, operating them as passenger aircraft, rather than cargo or combi aircraft.
C-40B
The C-40B is the least common variant, with only four having been built. For the most part, they serve as “flying offices”. They are mostly used by high ranking USAF and military officials, as well as politicians.
Due to this, the C-40B is laid out in a business class configuration with built in work stations at the front of the aircraft. At the rear, there is a “distinguished visitor” compartment, which contains sleeping quarters and a galley.
As a flying office, the C-40B is equipped with high speed internet, secure communications and satellite phones. There is even a large printer and photocopier onboard in case they need it!
On top of this, the aircraft also contains a conference room, otherwise known as a command room. This allows high ranking government and military leaders to discuss military and political matters.
C-40C
The C-40C is the second most common C-40 variant, with seven having been built. Where the C-40B is the flying office for the USAF (and other branches of the government), the C-40C is the passenger aircraft for the USAF (Reserve).
Due to this role, it is the first passenger aircraft in US military history to be “off the shelf”, being bought exactly the same way a Boeing 737-700 (BBJ) would be bought, as well as being built as just another 737-700.
For the most part, the aircraft will be used to transport officers and high ranking NCOs on longer distances. Depending on the configuration, the C-40C can carry between 42 and 111 passengers.
It is mostly used on routes that aircraft like the C-130 are too small to accommodate. Alternatively, they are used on routes when C-130s are busy transporting other things, such as tanks and other military equipment.
Specifications
Despite being used by three different US military branches for different roles, and three different Clipper variants existing, there isn’t actually any difference between them. At least in terms of specs.
This means, that if push comes to shove, all USAF, USN and USMC Clippers could be used in the same capacities, just down to their specs!
| Specifications | Boeing C-40 Clipper |
|---|---|
| Length | 110 ft 4 in (33.63 m) |
| Wingspan | 112 ft 7 in (34.3 m) |
| Height | 41 ft 2 in (12.55 m) |
| Crew | 6 (two pilots; one crew chief; one loadmaster and two second loadmasters) |
| Seats | 121 |
| Cargo | 8 pallets |
| Combi | 3 pallets; 70 passengers |
| Cruise Speed | Mach 0.781 (834 km/h; 600 mph; 450 kn) |
| Range | 5,000 nmi (9,300 km; 5,800 mi) |
| Service Ceiling | 41,000 ft (13,000 m) |
| MTOW | 171,000 lbs (77,600 kg) |
How Safe is The Boeing C-40 Clipper?
The C-40 is a military aircraft first, and a transport aircraft second. When a C-40 is flying, it is quite often a flying target, especially if it is being used to transport high-level officers from any of the three operators.
Despite having been in service since April 2001, often flying to and from warzones, the C-40 has never once had a crash. On top of this, there have never been any reported incidents with the type either.
However, these aircraft will likely be in service for several more years, serving in whatever wars and conflicts America gets itself into. So, future crashes and/or incidents may be in store.
The C-40 is a military variant of the Boeing 737-700 BBJ. To date, there have been no crashes and/or incidents involving a 737-700 BBJ, making it among the safest private jets.
The 737-700 BBJ itself is a variant of the Boeing 737-700 airliner. In recent years, the 737 MAX, and by extension the entire 737 family, has gotten a bad reputation for the two high profile 737 MAX crashes.
Despite this, the 737-700 isn’t related to the 737 MAX (at least not for the systems that caused the crashes). In fact, the 737-700 is among the safest aircraft to fly!
What’s it Like to Fly (on) a Boeing C-40 Clipper?
Rather unusually, I have been able to interview several people who’ve flown on the Boeing C-40 Clipper in various different capacities.
I was actually able to interview an ex-Navy C-40 pilot, who now flies for United (737-700). Here is what he had to say:
The Boeing C-40 Clipper is noticeably heavier than the standard 737-700. This results in a higher speed before I can takeoff, which I still haven’t fully adjusted to, even after a few years of flying with the airline.
I also find that the Clipper is much smoother. I can’t really explain why, but, at least to me anyway, the Clipper seems to just glide through the air, whilst the -700 seems to judder almost.
However, this may just be that the routes I am flying on are way different than the routes I flew on for the Navy in the Boeing C-40 Clipper!
On top of this, I was also able to interview an aide to a high level politician, who regularly flies on the C-40 (the interviewee requested that we keep them anonymous). Here is what they had to say:
I fly with [the politician] quite a bit. I’ve flown with them on quite a few aircraft, ranging from small private jets to rented out 747s to military aircraft like the C-40.
When it comes to working on them, I find the Clipper to be more like an office than any other aircraft. For many of the aircraft, the internet, whilst fast, is a little bit choppy, and the satellite phones are horrendous!
However, the Clipper has a large conference room, printers and photocopiers as well as places to sit and relax. You don’t get them on a small Cessna!
Legacy
Despite the Boeing C-40 Clipper only recently being withdrawn from production, it is still in service with three US military branches. As such, it is leaving a legacy on the industry as a whole, everyday it is in service!
Military Aviation
Although it is still in service, the Clipper has already proven itself to have left a rather large impact on military aviation. Chief among these is the continuation of “flying offices”.
Prior to the C-40, they were very common, with the US and other allied militaries having them. However, with the turn of the century, many military analysts wondered if it would continue. The C-40 proved it would.
And the US aren’t alone in this. The Europeans have converted a series of A330 MRTTs (otherwise known as Voyagers) into “flying offices”. As have the Russians with the Il-96.
Despite being almost 20 years old, the USAF, USMC and US Navy currently have no intention to replace it. By most estimates, it looks as though the C-40 will be in service for another 20 years or so.
Boeing 737
In recent years, the 737 family has gotten a bit of a bad reputation. The grounding of the 737 MAX in particular has sent shock waves throughout the industry, and has forever tarnished the 737 brand.
However, for many people in the military who’ve flown on a 737-derived Boeing C-40, it reinforces that the 737 MAX was just a bad apple. It wasn’t the aircraft itself that failed, but the subsequent engineering that did.
When it came to designing the 737 MAX, Boeing revisited several of the design ideas regarding the C-40. Thanks to modern technology these design applications were now much easier, and didn’t impact too much on weight.
As such, many of them were included on the 737 MAX family. This has helped to make it quite successful, even if it has been grounded for well over a year…
Boeing-Military Relations
US Military and Boeing relations have been somewhat distant for much of the 21st Century. Yes, both the US Military and Boeing have collaborated on several projects, but often, these contracts have gone to Lockheed Martin.
Think about aircraft like the Boeing X-32, which was cheaper than the Lockheed Martin X-35, yet the latter still won.
However, the C-40 is one of the few aircraft that the US military has actually accepted from Boeing. This has helped to keep US Military-Boeing relations alive, with the latter continuing to research new types of military aircraft.
Thanks in part to the success of the Boeing C-40 Clipper as well as previous Boeing transport aircraft, the US Military will likely continue to use Boeing for their future long-haul transport aircraft!
What do you think of the Boeing C-40 Clipper? Have ever flown (on) one? Tell me in the comments!