Over the last decade, the Royal Air Force has made some very deep budget cuts while also trying to modernize its much smaller aircraft fleet. Part of this plan saw its Lockheed L-1011 based TriStars being retired. Not to worry,

Offered for sale by , an international aircraft sales and leasing outfit out of Palos Verdes, CA, the TriStar tanker in question is a mult-irole leviathan of the skies. She can seat 266 passengers and can carry a whopping 300,000lbs of jet fuel that can be passed to any aircraft that can keep up with her and is equipped with a standard "hose and drogue" refueling probe.

If you are not interested in refueling everything from Super Hornets to RAF E-3 Sentries, or taking 266 of your friends a third of the way around the world, then you can use the TriStar for hauling outsized cargo, as its massive clam-shell cargo door can swallow anything from cargo containers to Humvees.

Originally, the TriStar for sale served with out of RAF Brize Norton, and was one of a fleet of 9 similar aircraft, of which there were four unique configurations. These aircraft were all L-1011-500 variants and came second hand from Pan Am and British Airways surplus stocks in the mid 1980s before being converted for their various roles.

The TriStar K1 was a passenger-tanker configuration without a cargo door, two of which were procured. Four KC1s could operate as either a passenger aircraft, a cargo hauler or a tanker. The remaining three aircraft were passenger configured with some cargo hauling ability, known the TriStar C2 and C2A. The TriStar C2 could also be used in an aeromedical format for medical transport and surgery, while the C2A had a modernized passenger interior and some militarized avionics that the other aircraft in the fleet lacked.

The RAF originally pursued the aircraft after the Falklands War highlighted the need for a long-range heavy tanker capability, as the tankers were rapidly reaching the end of their design life and only had a fraction of the TriStar's fuel off-loading capability. Also, the TriStar's added cargo and passenger carrying ability was seen as a major plus for the RAF in comparison to a dedicated tanker.

Lockheed TriStars saw action in every major conflict NATO or the RAF were a part of from the late 1980s on, with its last combat operation being the UK's airstrikes on Libya in 2011. During this operation, the RAFs TriStars were were key in ferrying carrying Tornadoes from their home bases in the UK to their launching positions high above the Mediterranean.

RAF's tanker TriStars had a unique 'dual basket' hose and drogue installation located at the rear centerline of the aircraft. Only one basket could be used at a time, but having two available should one fail, or break away during refueling, would make it so such an occurrence would not result in a mission fail. Some of the RAF's TriStar tankers also have refueling probes of their own, mounted above the cockpit in a streamlined fairing. This would allow for a TriStar coming off station to pass its extra gas to the one taking its place, which was much appreciated during high-temp combat operations.

There was some talk that a couple of the TriStars would get a multiple point refueling style system (MPRS), with the addition of hose and drogue pods on the wings, but nothing every came of this as the jets were slated for retirement shortly after this modification was being debated.

The TriStar was replaced in RAF service under the program, that would see the take the place of not just the RAF's TriStars but also their smaller

Although the MRTTs, known as "Voyagers" in RAF service, would cost less to operate than the TriStars they were replacing, and they would be more reliable, the financial agreement that the aircraft were procured under was seen as suspect by many. RAF leases nine core aircraft via a 'private finance initiative,' while another five Voyagers will be used for commercial operations, such as contracted passenger flights and for providing tanker capabilities for other NATO nations. This hybrid scheme sees the aircraft maintained, and partially crewed, by private contractors, not RAF personnel, which was not the case with the TriStar or the VC10 fleet.

As far as a market for this third-hand TriStar tanker, well it has just under 32,000 hours, which sounds like a lot, but it is not nearly as high as many airliners and transport aircraft flying today. The TriStars have been out of production for 30 years, and there serviceability is more challenging than their modern twin-engine equivalents, yet seeing as so few are in service, spare parts are still available from recently retired airframes.

The fact that the big jet can do so many things, hauling cargo, flying passengers, and especially passing fuel to hungry fighters, makes it an attractive option for the commercial air service provider market. Companies like Air Refueling, and even the TriStar's replacement MRTT holding companyitself, are heavily tasked and expanding, especially under the budget crunch of the last half decade.

Many nations need aerial refueling training and long-range tanker-transport capabilities but simply cannot afford to own and operate their own aircraft. So instead, they seek on-demand services that don't have the associated overhead of operating a fleet of these giants. As tactical aircraft, such as the F-35, continue to be more and more expensive to buy and operate, even less money will be available for support assets like tankers, so just like , the commercial air tanker marketplace is set to explode.

Seeing as the RAF's TriStar fleet was updated with modern to defend itself against advanced shoulder-fired missiles while operating in hostile territories, the ability to operate out of contested areas is also a huge plus. Even if this equipment has been stripped from the aircraft, the modifications to its structure are there and it could be re-installed, albeit at about the same cost as the entire aircraft itself. Still, militaries will be willing to pay a premium for such a service, as they will really have no other choice during high-tempo combat operations.

The RAF's ex-TriStars are in need of a cockpit update so that they can be compliant with the latest international air traffic and navigational standards. An upgrade was planned for the jets but it was cancelled due to their impending retirement. This would not be a cheap modification, but it would allow the TriStar to operate in virtually any airspace without additional approval or cost.

Just in case one TriStar is not enough, CSDS , although this one has an additional 20k hours on it and it appears to be a C2 version that is not tanker capable. It does have the ability to be turned into an advanced aeromedical facility, and as we recently saw with the Ebola outbreak in Western Africa, , and some NGOs have also deployed

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In any case, the availability of a second RAF TriStar, and for less than half the price of the tanker version at $700k, means that a buyer could have a spare parts aircraft of their own, including an extra trio of Rolls-Royce RB.211-524B turbofan engines.

So if you have a few million bucks burning a hole in your pocket, and you have always wanted to start your own aerial tanking business, or you are someone that already has a fleet of your own tanker capable commercial adversary aircraft, give the guys as CSDS a call. Who knows, with a little luck and a lot of green you will be topping off thirsty Super Hornets and Typhoons in no time.