The TWZ Newsletter
Weekly insights and analysis on the latest developments in military technology, strategy, and foreign policy.
Terms of Service and Privacy Policy
A U.S. Air Force challenge coin provides us with our best indication so far that the United States has brought nuclear bombs back to the United Kingdom after nearly two decades. As we have written about in the past, the move was long expected, with construction work at RAF Lakenheath in England already providing conclusive evidence that this was planned. More recently, a series of transatlantic flights by U.S. Air Force transport aircraft have also provided further indications of the movement of the bombs themselves to the United Kingdom.
Challenge coins, also known as ‘round metal objects,’ or RMOs, are a major part of military aviation culture and tradition, as you can read about here. Typically, these coins include features such as the unit designation, colors, mascot, nickname, mottos and slogans, symbology, and references to its history and lore. The coin in question is from the 493rd Fighter Generation Squadron (FGS), which is part of Lakenheath’s 48th Fighter Wing, and which was activated on June 9, 2023.
It would seem the B61s are back at #Lakenheath #RIAT2025 #RIAT pic.twitter.com/dT0U6MXjQ0
Tony Osborne, European Defense Editor at Aviation Week, photographed an example of the 493rd FGS challenge coin at the Royal International Air Tattoo airshow that took place over the weekend at RAF Fairford in England. On one side, the coin shows the grim reaper mascot of the 493rd Fighter Squadron, with its motto, “Prepare to meet thy maker.” In the center of the coin is the telltale shape of a B61 nuclear gravity bomb.
The entire shape of the coin makes very explicit one key aspect of the 493rd FGS mission, with a nuclear explosion and a mushroom cloud. The reverse of the coin provides a full-color depiction of the same explosion.
According to the Air Force, the 493rd FGS (and the sister 494th FGS) are the first fifth-generation squadrons of their kind in the European theater, replacing the 748th Aircraft Maintenance Squadron at Lakenheath.
“The idea to break large aircraft maintenance squadrons into smaller FGSs and pairing them up with their respective fighter squadrons aligns with the U.S. Air Force’s Combat Oriented Maintenance Organization (COMO) structure; aimed to foster unity of effort between maintenance and operations as well as enhance readiness of the squadrons,” the Air Force said in an official press release.
Now, each of the four fighter squadrons within the 48th Fighter Wing has a dedicated FGS assigned to it. In this case, the 493rd and 494th FGS correspond to the 493rd and 494th Fighter squadrons, both flying the F-35A. In 2021, Lakenheath became the first Air Force wing outside of the United States to operate the F-35A.
The other two fighter squadrons at Lakenheath still operate the F-15E — for now, at least.
Both the F-15E and F-35A are capable of carrying B61 series free-fall thermonuclear bombs and are therefore a critical part of the U.S. military posture in Europe. These aircraft can also make full use of the capabilities of the B61-12 version of the bomb, an advantage that doesn’t extend to all NATO aircraft cleared to carry the weapon, as we have discussed in the past.
Until recently, however, there were no nuclear bombs actually stored at Lakenheath.
Historically, Lakenheath had a nuclear mission, although the last nuclear weapons were removed from the base in 2008.
But there is no doubt that the weapons — or at the very least the related capabilities and infrastructure — are headed back to the base, if they are not there already.
When asked about the current status of nuclear weapons at Lakenheath, a U.S. Department of Defense official told TWZ: “Consistent with long-standing U.S. policy, we neither confirm nor deny the absence or presence of U.S. nuclear weapons at any specific location.”
Last week, open-source intelligence (OSINT) accounts on social media identified an Air Force C-17A transport flight that might have been connected with the movement of B61 nuclear bombs from the United States to Lakenheath. The callsign RCH4574 “followed the pattern of similar nuclear swaps,” according to the @TheIntelFrog. Of course, the Pentagon does not comment on whether such flights relate to the transport of U.S. nuclear weapons, although the 62nd Airlift Wing, to which the aircraft was assigned, is known to be the only one of its kind certified to ferry routine nuclear weapons shipments.
Today, 18 July, RCH4574 concluded it's mission and returned home to McChord AFB, WA. This would indicate that this was a drop off rather than a swap. During a swap, the aircraft returns to Kirtland and unloads on Pad 5 much like they loaded.
8/ pic.twitter.com/OIjaTWFAZs
The mission in question, on July 15, saw the C-17A arrive at Kirtland Air Force Base, New Mexico, from McChord Air Force Base, Washington. Once at Kirtland, it was noted in the area where nuclear weapons are loaded and unloaded by the resident Air Force Nuclear Weapons Center. The C-17A departed Kirtland on July 17 and arrived at Lakenheath the following day. Otherwise, the flight was more consistent with a nuclear weapons drop-off than a routine weapons swap.
The arrival of nuclear weapons at Lakenheath at this time wouldn’t be a surprise.
Earlier this year, we discussed the latest report on the subject from the Federation of American Scientists (FAS), which has been monitoring the topic since April 2022, when the first official evidence emerged suggesting the reactivation of the nuclear mission at Lakenheath.
As of February 2025, there was, according to FAS, “no known public indications that nuclear weapons have been deployed to RAF Lakenheath,” although it was abundantly clear that this was mostly a matter of time.
In the last few years, satellite imagery has confirmed upgrades being made to Lakenheath’s Protective Aircraft Shelters, which incorporate underground WS3 vaults for the storage of nuclear bombs. This work began in 2022, and, by early this year, around 28 of the 33 aircraft shelters had been upgraded, with construction continuing on six more.
Other infrastructure changes relate to the recently arrived F-35A squadrons. Specifically, the new tarmac infrastructure for these fighters mirror those found at other air bases in Europe that are known to host U.S. nuclear weapons.
At the same time, there have been various official references in Pentagon documents that connect construction work at the base with the Air Force’s nuclear mission.
For example, the NATO Security Investment Program (NSIP) budget for Fiscal Year 2023 includes the United Kingdom on a list of bases receiving upgrades to their “special storage” sites. The only candidate for this would be Lakenheath.
Furthermore, past U.S. Department of Defense procurement contracts describe plans for the “upcoming nuclear mission” for the Lakenheath-based 48th Security Forces Squadron (SFS).
As well as upgrades to facilities, Pentagon documents from 2023 reveal that specific training is now being given to nuclear weapons personnel at Lakenheath.
All of this, combined with the latest developments in terms of the 493rd FGS challenge coin and last week’s C-17A flight from Kirtland, strongly points to nuclear weapons having returned to Lakenheath.
It’s unclear, however, if the plan is for nuclear bombs to be permanently stationed at the base, with some suggestions in the past that the infrastructure there might be intended as a backup to other nuclear bases in Europe.
As of 2025, those other bases are Kleine Brogel in Belgium, Büchel in Germany, Aviano and Ghedi in Italy, Volkel in the Netherlands, and Incirlik in Turkey. Of these, the Netherlands notably declared its F-35As fully responsible for the nuclear strike role as of June 2024. Incirlik is meanwhile notable as the weapons here cannot actually be employed by Turkey, in contrast to the ‘dual-key’ arrangement with other nuclear-sharing nations.
As a backup base, Lakenheath could potentially receive nuclear weapons from other bases in Europe or even from the United States in a time of crisis. This would, to a limited degree, increase the flexibility of the nuclear mission in Europe. Perhaps, further C-17A flights might help confirm whether the base is intended as a permanent home of nuclear weapons, or if they will be rotated in and out on a temporary basis.
There is also the possibility that Lakenheath’s nuclear role might become more important in the future, should Washington decide on a drawdown of U.S.-owned nuclear weapons elsewhere in Europe, something that TWZ has also previously considered.
Then there is the question of how nuclear weapons at Lakenheath might overlap with the United Kingdom’s recently announced plans to buy F-35As as well as the short takeoff and vertical landing (STOVL) F-35B models it already uses. The U.K. Ministry of Defense has highlighted the F-35A’s nuclear mission, which would see the jets armed with U.S.-owned B61-12 bombs. Potentially, Royal Air Force F-35As could use these bombs too, and small detachments of British aircraft at the base might also be an option.
My understanding is that B61s hosted by the UK would not be stored at Marham, but at Lakenheath, which is already upgraded. Obviously that would mean that F-35As would need to go from one to the other. UK/NATO do not comment on nuclear storage. But watch budgets. https://t.co/yNpdxHgic6
Regardless, having another base capable of launching strikes involving B61-12 bombs is significant.
FAS estimates that around 100 U.S.-owned B61-12 gravity bombs are available across the aforementioned NATO air bases in Europe.
In the past, we have pointed out the specific new capabilities that the B61-12 brings:
Thanks to its precision-guidance system, which combines a new tail kit with an inertial navigation system package and rockets for spin stabilization, the B61-12 offers increased accuracy over older B61 versions. When combined with the F-35A, the B61-12 is increasingly being viewed as a strategic weapons-delivery system, as well as a tactical strike asset.
Since President Donald Trump took office, there has been some uncertainty among NATO’s leading European powers that Washington may dial back or even end the current nuclear-sharing program, something we have recently discussed. This has prompted some of those powers, notably France and the United Kingdom, to start to look at alternatives, including some kind of cooperative nuclear umbrella independent of the United States. All this is being played out against the backdrop of growing tensions between NATO and Russia in recent years.
With U.S.-owned nuclear weapons having arrived (or otherwise very soon to arrive) at an additional European base, those fears might be allayed somewhat, although it remains to be seen whether the bombs will be a permanent fixture at the base.
Contact the author: thomas@thewarzone.com
External fuel tanks for the F-35 have never materialized after past development efforts, but now they are back on program's to do list.
Reintroducing an air-launched nuclear capability is a big deal for the United Kingdom, but it will come with certain caveats.
Weekly insights and analysis on the latest developments in military technology, strategy, and foreign policy.
By signing up you agree to our Terms of Service and Privacy Policy.
Weekly insights and analysis on the latest developments in military technology, strategy, and foreign policy.
By signing up you agree to our Terms of Service and Privacy Policy.
© 2024 Recurrent Ventures. All Rights Reserved.
Articles may contain affiliate links which enable us to share in the revenue of any purchases made.
