December 25, 2021: In late 2021 the United States halted its efforts to get Israel two KC-46A aerial tankers as soon as possible. The reason given was the growing backlog of late deliveries to the U.S. Air Force. Israel suspects the Americans are also trying to make it more difficult for the Israelis to carry out a massive air attack on Iranian nuclear facilities.

This all began in late 2019 when the Israeli Air Force (IAF) asked the United States to supply them with two new KC-46A tankers as soon as possible. While the KC-46A has had some manufacturing problems, once checked over carefully it is good to go as a modern aerial tanker and transport. Israel is getting somewhat desperate in this area. Although a small country with no imminent threat from a neighboring military, Israel has long maintained a large force of aerial tankers. Nine of those are Boeing 707 airliners purchased second-hand decades ago and converted to tankers like the American KC-135. There are also four KC-130H turboprop tankers like those used by the United States and are better suited to refueling helicopters. Most Israeli combat and transport helicopters are equipped for aerial refueling. In most instances, the refueling enables aircraft to stay in the air longer when that is needed to deal with an uncertain situation that requires prompt attention from aircraft already in the air. The big problem is the age and heavy maintenance requirements for these elderly Israeli B-707 tankers. Making a long-range airstrike against Iran is a lot riskier because tanker availability and reliability is less certain.

Boeing, the manufacturer of the 707, KC-135s and the new KC46A was amenable to giving Israel two 46As right away but the U.S. Air Force had to cooperate and allow two of theirs to be diverted to Israel. This would be good for Boeing because Israel would put the KC-46As to work right away and thereby foster more Boeing export sales. The pitch to the U.S. Air Force is that the Israeli experience would be valuable in ongoing efforts to improve the quality of production and implementation of needed or suggested improvements.

Israel wants to buy up to eight KC-46As, for about a billion dollars. Growing problems with the elderly Israeli 707 tankers and production problems with the KC-46As, plus the Israeli resistance to buying expensive new support aircraft, further complicated matters. That need for KC-46As became more urgent as the 707 situation got worse faster than expected while the KC-46A finally entered service in 2019 and long-distance strikes against Iran became more likely. Israel is trying to work through all this and solve its escalating aerial refueling crises. By 2021 the KC-46A looked less attractive because additional manufacturing and design problems continued to show up.

Earlier in 2019, the U.S. air force resumed, after a two-month delay, accepting new KC-46As. That two-month delay was because of FOD (Foreign Object Debris), including tools and other metal objects, still showing up in various parts of the aircraft. This indicated a serious lapse in the management of assembly and quality control while producing these aircraft. By March 2019, after nearly a month of effort to check out aircraft nearly ready for delivery as well as factory inspection procedures, the air force agreed to begin accepting KC-46s once more. Deliveries continued despite a recently discovered cargo lock (unreliable cargo tie-down latches) problem. The Americans are now concerned about Boeing, the manufacturer, while also needing the KC-46As as soon as possible. This is the same firm that is having worse problems with its new 737 Max commercial airliner.

In mid-2019 Boeing planned to deliver 36 KC-46As by the end of 2019 and later expected to meet that goal even though only 19 had been delivered by early September. At the end of the year, the goal of 36 was missed but Boeing did fix the cargo lock problem and this allowed cargo to again be carried. There was one problem left with the accuracy of the remote viewing system used by the 46A boom operator. That does not prevent the operation of the aircraft, it just slows down refueling in some cases. The latest (early 2021) problem is leaky toilets. Most tankers are based on commercial freight transports, with the addition of more onboard fuel and aerial refueling equipment. There is a lot of space left for passengers and cargo. The KC-46 can carry over a hundred passengers and when it does the crew toilet is not sufficient. There was already a cargo pallet based ATGL (Air Transportable Galley-Lavatory) in use with the C-17 and C-130 transports. These aircraft alternate between carrying all cargo, mixed (cargo/passenger) and all-passenger modes. Boeing, the developer of the KC-46 was told to make sure the KC-46 could easily handle the ATGL. It was a simple request for a simple task; just note the ATGL specs and their use on the other transports and the job is done. Like so many other simple design and construction tasks on the KC-46, Boeing got it wrong. They moved the orientation of the ATGL 90 degrees to fit into the KC-46 and did not note that the ATGL anti-spill valve did not work reliably in the new orientation. Boeing did not discover that until the ATGL underwent testing on the KC-46 and the leak problem became obvious. Now a new valve must be developed and tested, and there is no certainty when that will get done. Based on the many past problems with the KC-46, these avoidable problems take longer than anticipated to fix. Some problems discovered several years ago are still unresolved.

Boeing was in a hurry to deliver nearly 200 KC-46As to the air force and was telling Israel that once an order is approved it can take two or three years to deliver the KC-46As. Israel apparently no longer has that much time, especially with the Iranian crisis getting worse.

On the plus side, the elderly U.S. KC-135 tanker fleet is in much better shape than Israeli B-707 tankers. The main problem Israel has is that the 707 based aircraft are very old. The oldest 707 was built in 1958 and the youngest ones are from the 1970s. Most commercial 707s retired decades ago. Obtaining spare parts has become increasingly difficult. In 2018 the IAF paid Brazil $400,000 for a 707 retired in 2008, plus a stock of 707 spare parts. The Brazilian 707 was then taken apart for spares. All IAF tankers were grounded for more than a month in 2019 because inexperienced civilian maintainers caused an accident that had to be investigated to ensure that there was not a more fundamental problem with the aircraft. Production of civilian 707s ended in 1978 but the production of military versions, which mainly went to the U.S. Air Force, continued into the early 1990s. The United States used to be a primary source of spare parts but now those spares are needed to keep dozens of American military 707s operational.

Israel had closely followed the American search for a new tanker to replace the elderly KC-135 because they realized that Israeli tankers were older than the American ones. The Boeing 707 became obsolete at the end of the 20th century, as most countries adopted new jet engine noise regulations that barred the use of 707s at major airports and many minor ones. You could upgrade the 707, with new engines, to comply, but it was cheaper to buy a new aircraft that was cheaper and safer to operate than the elderly 707. Only 1,010 707s were built from 1958 to 1979 and it was a sturdy and reliable carrier of freight, as well as passengers, and continued in use for decades before rising fuel prices and maintenance costs made it too expensive for commercial use.

The Boeing 707 commercial transport is a civilian version of the original KC-135 of which 732 were built between 1956 and 1965. The KC-135 evolved from the World War II B-29 heavy bomber. The U.S. Air Force used to be a major player in the second-hand 707 market as the military was, until a decade ago, converting them to military uses (AWACS and J-STARS), but even that has shifted to more modern aircraft designs. By the early 2000s, you would buy an old 707 for less than a million bucks, then spend $25 million turning it into an aerial tanker or several times that to produce an AWACs. These days, the Boeing 737 is preferred for this sort of thing.

That led to the new U.S. Air Force KC-46A tanker aircraft. There were a lot of problems converting 767s to the KC-46, but most were caused by sloppiness at Boeing manufacturing plants. Like the 707 tankers, the KC-46 can also carry cargo, a lot of it. The KC-46A can carry 29.5 tons of cargo in up to 18 pallets. The KC-46A can also carry up to 114 passengers or 58 patients (plus medical personnel).

The total value of the project, to replace the aging fleet of KC-135 and KC-10 tankers, could be as high as $44 billion. The initial order was for 18 aircraft at about $150 million each. That initial order also came with about a billion dollars for development work plus $4 billion in additional development costs that the manufacturer absorbed. The air force might order over a hundred KC-46As, but the exact number depends on what kind of future aircraft the air force will be using. If there are a lot of unmanned aircraft (UAVs), fewer tankers will be needed because UAVs are smaller, and need less fuel.

The competition between the American (Boeing) and European (AirBus) candidates was quite close. The KC-330 carries 20 percent more fuel than the KC-767, plus 37 percent more cargo pallets and passengers. But this apparently worked against the KC-330, as the KC-767 is closer in size to the KC-135, and thus will not require as many new maintenance facilities. The KC-767 is also considered easier and cheaper to maintain. The KC-330/45A was to have cost about $175 million each, 17 percent more than the KC-46A.

The KC-46A is based on the Boeing 767-200 airliner, which sells for about $120 million. The 767 has been in service since 1982, and over 1,100 have been manufactured so far. Boeing developed the KC-46A on its own, at a cost of nearly a billion dollars. Boeing also developed the original KC-135 tanker in the 1950s and has since built over 2,000 of these.

The two engine KC-330 (KC-45A) was based on the AirBus 330, which costs about $160 million each. Over 1,400 330s have been produced since the aircraft entered service in 1994. Both candidates were selected for their ability to replace the four-engine KC-135. This older aircraft carries 90 tons of fuel and can transfer up to 68 tons. Typically, aerial tankers service B-52s (which carry over 140 tons of jet fuel) and fighters like the F-15 (over five tons). The KC-135 has long made itself useful carrying cargo and passengers, as well as fuel, and both the KC-767 and KC-30 have more capacity for this. The KC-46A can pump 1,200 gallons (4,900 liters) a minute total while each of the underwing pods can deliver a third of that per minute.

With the continued KC-46A delays most export sales went to the KC-330s, now called the A330 MRTT or KC-30A. So far, 50 of these have been ordered by or delivered to Australia, France, NATO, Saudi Arabia, the United Arab Emirates, Singapore, South Korea, and Britain. The KC-46A has two export customers so far; Israel (8 KC-46As) and Japan (2). Several other nations are considering the KC-46A, but all these problems don’t help with turning consideration into orders.