On 9 March 2023, a webcam caught Iranian frigate IRIS Dena (F-75) underway departing Rio de Janeiro at the end of an extended port visit that began on 26 February 2023.
Forward support base IRINS Makran (441) was presumably in company with Dena. Although Iran’s leaders have threatened to send the two-ship flotilla through the Panama Canal on this “round the world” deployment, it has been a vexed question from the beginning where the ships are at a given time, and it isn’t clear if they’re headed for the canal now.
There is naturally speculation that the warships will stop in Venezuela next. If they do, they could already be off the coast from Caracas given their departure from Rio on Thursday. They are likely, however, to make the transit more slowly, in keeping with their deployment profile to date.
That deployment is what we’re here to ponder.
The story so far
Dena and Makran left Bandar Abbas naval base on 30 September 2022. In spite of the Iranian announcement, there was practically no coverage in Western media at the time. The announcement was vague about the flotilla’s intentions, other than “to sail azure waters across the globe” with a message of “peace and friendship.”
The ships turned up in Jakarta on 5 November 2022. It’s a good question where they were between their departure from Bandas Abbas and their arrival in Indonesia, but it isn’t the purpose here to dwell on that point. On the other hand, what we do look at will shed light on the possibilities.
A report on 14 November indicated the ships left Jakarta on the 10th, and were said to be heading home (i.e., to the Persian Gulf). A tweet associated with the Indonesian navy appeared to show a salute to Dena from the pier in Jakarta that day.
It’s conceivable that Dena and Makran went home immediately afterward. I doubt that, however, because there’s no evidence of it, and the next place the 86th Flotilla showed up was even further east, just outside the EEZ of French Polynesia on 24 December 2022.
The sighting appears to have been on Christmas Eve. The tweet is dated 24 December, Tahiti time (i.e., where the French military command and ground support for the surveillance assets are located). Tahiti time is GMT-10, or the same as Hawai’i time. No time of detection was given, but the images are in daylight, and the tweet no doubt had to percolate through an approval process of a few hours before release. I doubt it was sent during the surveillance flight of the French Falcon 200. It was probably posted after the flight recovered on Tahiti. (A spot report in military channels would have been sent immediately.)
Interestingly, and not incidentally, the French command reported a patrol aircraft sighting a Chinese destroyer, also approaching the EEZ of French Polynesia, on 22 December 2022, shortly before the Iranian warships came through.
The Iranian ships on 24 December responded to a hail from the French aircrew and stated that they intended to continue an easterly transit south of the Marquesas Islands, the northernmost island group of French Polynesia. (See below for tons of maps.)
User:Tintazul derivative work: Cruickshanks – Own work, derivative of Oceania_ISO_3166-1.svg
So maybe the Iranians turned around after that interaction and headed back for Iran. They had time, if they moved fast enough, to make a transit from that location back across the South Pacific Islands and the Indian Ocean, and still make a late February-ish date in Rio.
But again, I seriously doubt that. There’s no evidence of it at all. The Iranian ships aren’t likely to travel fast enough to pull it off, because they’re limited in how Makran can refuel and resupply Dena. They don’t have the capability to replenish alongside while underway in the open ocean at transit speed. They have to stop to do it, and there’s no place in the open ocean to just stop for such a purpose.
Moreover, the next data point we got was confirmation from Australia in early January that Dena and Makran were known to have headed north, “toward the Philippine Sea,” when they left Jakarta in November. Australian sources indicated to a New Zealand news outlet (link) that the two warships were in the Solomon Islands before their sighting by the French on 24 December.
The Australians also said the Iranian flotilla didn’t at any time enter the Australian EEZ, nor did it transit the Torres Strait between Papua New Guinea and Australia.
The significance of that, besides confirming that the 86th Flotilla didn’t go home between Jakarta and the Christmas sighting by the French (a period of some six weeks), is that the Iranians were making an effort to take a longer route, avoid detection by Australia, and no doubt facilitate the flotilla’s method of refueling and resupply.
It’s that method that we’re here to look at. Western analysts have been reflexively thinking of Iran sending the ships westward from a departure point in the Persian Gulf. But a study of the options for limited-capacity replenishment shows they could have gotten to Rio by going eastward across the South Pacific. And if they doubled Cape Horn, they didn’t have to go through the Panama Canal – and we would know if they had – to get to Rio de Janeiro on 26 February 2023.
In fact, even after a relatively slow transit across the South Pacific, the flotilla would have had several weeks to linger after arriving off South America, waiting for a mid-to-late-February date to be confirmed with Rio. That comports with the sense of the very vague reporting about what the ships were doing all that time, speculation that boils down to drilling around off the coasts of Argentina, Uruguay, and Brazil.
For what it’s worth, a number of social media posts (mainly from Brazil) in fact stated that the Iranian ships had crossed the Pacific before entering Rio de Janeiro on 26 February.
The Panama Caper
To flesh out the timeline after the New Zealand report in early January, based on Australian sources, we need to look at what got everyone saying “Panama” about the Iranian task group. The “Panama” theme kicked in in mid-January, after Admiral Amir Shahram Irani, commander of the Iranian navy, announced that Iran planned to “be present” in the Panama “Strait” in 2023.
Speculation about this naturally involved the 86th Flotilla, although there was no crescendo of noise about it until the Washington Free Beacon reported on 26 January 2023 that the two Iranian warships had been given diplomatic clearance by Brazil for a port visit in Rio de Janeiro from 23 to 30 January.
The two ships didn’t enter Rio in January at all, or even show up on any publicly-available radar until a month later. The delay was attributed to U.S. objections to the port visit, and Brazilian President Lula da Silva’s visit to Washington, D.C. at the time of the originally scheduled port call in late January.
In hindsight, it appears that the stray reference by Iran to the ships being in the “western waters of Latin America” (see the thread) was valid for at least some period of time, though probably not between late January and 26 February. For reasons outlined below, I consider the comment basically misleading. It’s unlikely the flotilla spent more than a handful of days, if that, in the “western waters” of South America.
At any rate, articles in the popular military-oriented media took notice, shortly after Admiral Shahram Irani’s statement, of the inaugural outside-CONUS flight – off South America’s northeast coast – of a special-purpose U.S. Air Force surveillance aircraft, the WC-135R Constant Phoenix. The airframe is the newest in a family of planes with a mission of radiological air-sampling (“nuke-sniffing”), and the 16 January 2023 flight profile was quite unusual.
The Drive points out: “This particular flight was a so-called ‘baseline’ collection mission to gather air samples that are then used to establish what atmospheric radiation levels should look like under normal conditions.”
The flight may or may not have had anything to do with the Iranian flotilla, but its occurrence five days after Shahram Irani’s announcement was arresting. It also served to solidify a mental image of the Iranian warships being east of South America in their approach to the Panama Canal.
The same WC-135R flew a profile 12 days later, however, that crossed Panama and headed down the northwest coast of South America as far as the border of Peru and Chile, before turning back.
The baseline collection objective thus seems to have encompassed the coastlines stretching down from both sides of the Panama Canal. If it was related to the Iranian warships, my best estimate would be that it was, in fact, about collecting a sampling baseline before the ships made any transit of the area. In the relevant time period, in other words, Dena and Makran had not yet moved through the sample area on either side of Panama.
In summary, the “Panama” reference in mid-January got Western media focused on Panama and the eastern approaches to Latin America. That didn’t mean that’s where the Iranian ships were.
Limited-capability round-the-worlding
How about the feasibility and likelihood of the South Pacific transit?
I’ve written before about Iran’s replenishment restrictions, and will refer readers to this older post (and here) from the Iranians’ 2021 excursion to the Baltic Sea. In the Iranian navy’s previous deployments to Western waters, the ships involved have typically sustained an overall speed of advance (SOA) of 7 or 8 knots (nautical miles per hour). That doesn’t mean they’re transiting underway consistently at such speeds. (Much more typical for warships is about 15kts, or depending on daily tasks and orders, between 12kts and 18kts.)
It means the ships stop a lot, between underway periods in the 12-18 kt range. From point A to point B, and then M, and then X, they average 7-8kts.
One big reason the Iranian ships have to stop is so they can safely execute replenishment of the frigate, which needs fuel, stores, and probably some amount of potable water on a regular basis. Again, for more discussion of the mechanics, see my earlier article.
But let’s check out a couple of visuals below. The first images are from the 2021 deployment and show Makran with a fuel line running from the stern to Mowj (Moudge) class frigate Sahand (F-74), and a separate shot of the two ships moored together at the bow.
These connections can’t be maintained safely underway. The ships would need to pull into weather-protected areas for them.
This image is from the current deployment, and shows Dena moored alongside Makran, with slack lines, no white wake, and a transfer line for liquids running from Makran’s deck to Dena.
(My guess on the liquids transfer is potable water, based on the container it’s coming from.)
The sea state is very calm in the image from the current deployment. We can’t see how close to shore the ships are, but it’s probably not far (though we also have no idea where the ships were on the map at the time). An anchor chain is visible off Makran’s port bow, so the ships are in an area where the depth is anchorable (probably less than about 200 fathoms, or 1200 feet).
Maritime access
The problem with this elaborate set-up is finding places to stop that are shallow enough, offer relatively calm waters – and, if you’re Iran, don’t require seeking permission to enter another nation’s territorial seas.
The area up to 12 nautical miles (12NM) offshore from a littoral nation is recognized under the UN Convention on the Law of the Sea (UNCLOS) as that nation’s territorial seas. That’s the area where foreign ships need to seek permission to enter. (The littoral nations also have privileges in the contiguous zone, which extends to 24NM offshore, and the recognized EEZ, which goes up to 200NM. But foreign ships may operate in those areas without permission, depending on that they’re there for, since they are international waters.)
The Pacific Ocean presents a particular challenge, because quite a bit of it drops off very quickly offshore. In many cases, including much of the island region of Oceania and the west coast of South America, offshore depths reach more than 200 fathoms inside the 12NM limit of territorial waters.
So if you’re Iran and not very popular in terms of global diplomacy, the miles from Jakarta to the coast of Chile could look like a really long stretch without a drink of water, for you or your little frigate.
The secrecy factor
Moreover, it’s not just that the Iranian navy may have difficulty finding diplomatic cooperation for refueling points.
Iran might find enough of them to keep a transit going. But every diplomatic interaction, and every stop attended by overtness and visibility, advertises where Iran’s warships are.
We’ve seen in the previous deployments since 2014 that the Iranian regime prefers to maintain deception and secrecy. (Note: there are links to just about all my previous articles, going back to 2014, in the links included in this one.)
There was evidence, even when the 2021 task group entered and left the busy, closely-observed Danish Straits that summer, that the Iranian ships sought to maintain an air of mystery by going silent and probably even making deceptive emissions. Prior to the warships popping up off Northern Europe, an Iranian admiral had briefed his nation on TV that the ships had gone through the middle of the South Atlantic – which it’s extremely unlikely they actually did.
A similar sequence of silences and surveillance-dodging attended a brief period of operations by the 2021 flotilla near the Strait of Gibraltar, which the Iranian warships feinted toward but may not have gone through at that particular time. Eventually one of them, Makran (which was deployed with the frigate Sahand), showed up in the Great Bitter Lake during a Suez Canal transit. No detections of either ship were reported in the Mediterranean, but collateral clues suggested that was, in fact, their homebound transit route.
In the current deployment, Iran conditioned foreign thinking with the announcement about going through the Panama Canal. Even after the visit to Jakarta in November, that turned eyes westward from Iran – by my calculation, just as the flotilla ships would have been showing up (in mid-January) off the southwestern coast of Chile. After the Jakarta port visit, it appears that another statement suggested the flotilla would go west toward home, when instead it went east and showed up in French Polynesia.
Later, whatever the Iranian flotilla was doing before it got to Rio, the regime was at pains to hide it.
The South Pacific is actually a pretty good place to bring that off. But it would depend on not leaving a trail of diplomatic clearances across the region for frequent replenishment stops in sheltered waters. Nations and media would all know about that within days of the first event.
So we can reasonably assume Iran didn’t want to advertise with a series of diplomatic concurrences, if it wasn’t necessary.
But Iran also wouldn’t want to set off alarm bells and noise by being chased from one unauthorized comfort stop to the next.
Regarding secrecy, this is a good time to take a look at the flow and heaviness of maritime traffic across the region. That would affect Iran’s route choices. The area being traversed and its proximity to the haunts of U.S. and U.S.-friendly surveillance assets would also factor in.
That makes a significant difference coming out of Jakarta, for example. My opinion is that the warships probably didn’t go as far north as the Philippine Sea. The South China Sea area to be crossed is under heavy surveillance by the assets of multiple nations, including the U.S. The likelihood of being detected there is very high. It’s possible to stay east of the most heavily-trafficked shipping lane, but doing so means wandering among the disputed South China Sea islands, and becoming famous on TV screens all around the littoral.
Since we know from the Australians that the flotilla didn’t do this leg by going south of Papua New Guinea, the brown-shaded transit route to the Solomons appears more likely to me.
The secret sauce?
With all that in mind, I posit that Iran may have used a couple of methods to get across the Pacific with enough replenishment stops to meet the need.
The first is suggested by the Australian report that the Iranian flotilla was known to have been in the Solomon Islands before showing up in French Polynesia. It’s conceivable that Iran’s ships stopped, unauthorized, in one or more remote areas of the Solomons, hoping not to be seen. That wouldn’t be impossible, per se. See some options depicted on the maps below, for which the key is that the islands are uninhabited.
In the Solomons, I don’t think those options are all that good. Even though some of the potential rest stops are fairly remote, and offer seaward-facing venues, the Solomons are relatively busy as Pacific islands go. The inhabited islands aren’t all that far away, and sightseeing flights and dive tours are regular occurrences.
But think back to our French sighting of the Chinese destroyer preceding the Iranian flotilla into the French Polynesian EEZ by a couple of days in December 2022.
China has been working overtime to develop strategic relationships with two archipelagic island nations in the kingdom of Oceania. One is the Solomon Islands. The other is Kiribati, east of the Solomons.
It’s by no means unthinkable that China could grease a little off-the-books rest-stop time for the Iranian navy, at the remoter, and especially uninhabited, islands those nations are afforded with.
The Solomon Islands’ remote locations may not be all that remote, in relative terms. But those of Kiribati are.
See the Phoenix Islands group, the central group in the vast Kiribati chain that runs from west to east. Most of the population is in the Gilbert Islands to the west, but the Phoenix Islands have only one inhabited island, Kanton.
The Phoenix Islands look like the prime spot to me, even though the Line Islands further east also have a nice selection of uninhabited locations. The uninhabited Line Islands aren’t to be sneezed at, but they are relatively close to some island real estate held by the United States. And they’re just at the edge of the French Polynesian EEZ, where the French surveillance patrol picked up the Iranians in transit, as it presumably picks up maritime traffic regularly in the execution of its mission.
Kiribati itself probably doesn’t keep the Line Islands under a rigorous watch. But we can assume dedicated French assets know pretty well what’s coming from the Line Islands heading southeast. We don’t know how far the French patrol aircraft look into the Line Islands, but we can guess that uninhabited Caroline, Flint, and even Vostok may not be where you’d want to shoot for secrecy.
The second method would be stopping around an uninhabited island or island group even without grease from China.
The flow of maritime movement in the Southeastern Pacific shows a considerable lightening of traffic east of the islands closer to Australia and Southeast Asia.
And the most interesting prospect for furtive, ungreased use of near-land waters, without the nicety of diplomatic clearance, is the Pitcairn Islands group.
Any due-diligence level of research confirms that there’s hardly any ocean-going traffic to and from the Pitcairn group. Only one of four islands – Pitcairn itself – is inhabited. The nearest other islands in the group, Oeno and Henderson, are beyond line of sight from Pitcairn. And the three uninhabited islands appear to afford a few spots where it remains shallow enough to anchor even outside the 12NM limit. (The UK owns the Pitcairn group.)
East of the Pitcairn Islands, sheltered anchorage stops would involve permission from the nations of South America (e.g., Easter Island and the Juan Fernandez volcanic islands, which belong to Chile, and further north, the Galapagos Islands of Ecuador). In that regard, it’s interesting to note another odd data point from this Iranian deployment.
The data point is a report at an Italian outlet that mentions Iran seeking clearance for Chile’s territorial waters, and not receiving it. It’s only a brief mention (citing Spanish news source ABC Internacional; paywall) and doesn’t state where Iran was seeking entry to Chilean territorial seas. It could have been the mainland coast, or Chile’s Pacific islands.
One thing that seems very unlikely is that Iran would have sought access to Chile’s mainland coast if the flotilla approached the continent from the eastern side. But when approaching it from the west, any of Chile’s waters would have been a natural place to try for a comfort stop.
Note, on this map, the inhospitable bottom topography of South America’s western coastline. Virtually all of it features the plunge into a trench just off the coast. There is hardly any spot where ships could come to rest outside the territorial seas of the littoral nations. It’s just too deep, too fast.
But on the eastern side of South America, relative shallows offshore afford better prospects.
The final sprint
If the Iranian transit looked something like the summary map above, there would have been a comfortable number of opportunities for sheltered replenishment between Jakarta and the Pitcairn Islands. Even assuming Iran was determined not to be seen, there are several well-placed locations for that, especially if replenishment is done at night.
The flotilla pair could even move around and linger in a good area rather than hastening through the island chains expeditiously. Lingering risked more notoriety than necessary in the Solomons, even with China’s grease to hold the diplomatic noise down. But it might have been possible to go to and fro in Kiribati, and walk up and down in it, for a week or more without risking too much. The same might have been the case with the Pitcairn group.
Jumping off from the Pitcairn Islands was the risky move from a mariner’s perspective. Without a guarantee of access to hospitable waters in Chile (or further north, though for secrecy’s sake I doubt that was on the table), Dena’s fuel state was going to run pretty far down.
The Iranian Mowj (or Moudge) class frigates, of which Dena is a specimen, were built largely copying the UK-made Vosper Mk 5 frigates (Alvand, Alborz, Sabalan, the now-defunct Sahand/ex-Faramarz) that for years formed the core of the Iranian navy. The Vosper Mk 5s have an unrefueled endurance of 5000NM at 15kts.
If the flotilla “sprinted” from the Pitcairns to the eastern side of Cape Horn at 12-14kts, it would take about 10-12 days to complete the leg, depending on route, and leave Dena between 30% and 40% on fuel. That wouldn’t be my condition of choice in which to double Cape Horn, even in the summer months. But it would be feasible, if the risk were accepted.
In the waiting room
Once we get the Iranian flotilla to the waters off Argentina, the main question that arises is how no one apparently saw the two ships in a period that, by my calculations, extended for some 35-48 days.
The question is there even if the ships (against all the evidence) approached from Africa instead of the South Pacific. They still had to remain undetected, or at least unreported, for some 5-6 weeks, while remaining close enough to the coast to nip in for a replenishment when necessary.
It’s worth pondering, given that neither Argentina nor Uruguay leaves its offshore area unpatrolled. Both nations have maritime boundary disputes, and are as assiduous as other nations with the same issues about watching their marine frontiers. Remaining unreported between Argentina and the Falklands, for example, is not something I’d expect to get away with for very long.
That said, the question isn’t that pressing for our purposes here. The consensus is that the Iranian ships did linger in the area in question, and no facts seem to contradict that. For completeness, I append a couple of maps showing – for the curious – what a few remote islands off South America and Antarctica seem to offer.
I consider it unlikely that the Iranian flotilla availed itself of these islands, although they’re generally uninhabited and would be at their most complaisant in the summer. The prevailing temperatures, winds, and seas wouldn’t be as bad as you might think.
But again, that’s just for completeness. I doubt the Iranians made use of them.
Parting thoughts
A few comments in conclusion.
One is that U.S. intelligence has the means to know where the Iranian ships were, at least most of the time.
From the appearance of the 2021 Iranian deployment, which seemed to be attended by surprise for NATO when the warships showed up off France instead of proceeding across the Atlantic as the public expected, it may be that the Iranians do succeed at masking their location for at least some intervals.
If Australia knew where the 86th Flotilla was after Jakarta, however, and then the French in Polynesia, we were aware of that information from our allies. Such cueing should have been enough to energize the appropriate surveillance.
When the Iranian admiral tweeted about the Panama Canal on 11 January, we should have had a good idea that the flotilla would be approaching South America from the west, across the South Pacific.
I’m not sure I see an upside to basically cooperating with Iran’s desire for secrecy, by leaving those details on the cutting-room floor in disclosures (or lack thereof) to the American public.
Iran’s desire to creep around the globe undetected, meanwhile – in fact, to drop misleading hints about the navy’s intentions and then do something else – is disquieting. There’s no good reason for it. It’s not a standard way of operating a blue-water navy in the modern world and peacetime seas. Even China is more conventional. The global navies don’t as a rule trumpet their tactical schedules well in advance, but that’s more for operational security (OPSEC) and good defense than it is for the offensive goal of springing surprises on others.
The profile of Iran’s current deployment has more in common with the desire of the Chinese Communist Party – lately discussed – to surprise the world with container missiles in foreign ports than it has with standard navy OPSEC.
Alert readers know that Iran has been playing hide-and-seek with her merchant fleet for years. Operating a navy that way brings nothing but downside for the high seas, foreign adversaries, and the rest of the planet.
Feature image: Iranian frigate IRIS Dena (F-75) arrives in Rio de Janeiro 26 Feb 2023. Video via Twitter.
The Optimistic Conservative 
Thank you for this analysis and for the information: interesting indeed!
While I have no doubts that China is clearly seeking to establish “forward positions” around the globe, as you so well describe in your previous item, I am less convinced that Iran has the capacity to do so, though, like all independent navies, it must consider it’s ability to reach around the globe.
On a personal note, I was in Iran at the back end of ’79 (you remember that time?), and found it quite divided then, as it has remained since. But I also accept that the UK and USA had seriously negative impacts on Iran previously, leading to the Shah’s reign and to a saddistic security force (Savak). The result was that Ayatollah Khomenei had massive public support. But there has remained an antagonism between the USA and Iran that is simply not healthy for either. One could even argue that Iran is more sinned against, than sinning (the list is long).
If you were “them”, wouldn’t you be doing exactly what they are doing? (or have done it 10 years ago!)
Or is “One-frigate-and-its-support-ship” just one more example of perceptual overreach (a FLOTILLA!).
Welcome, Colin Bell, and my apologies for the delay in “approving” your comment.
One “approval” should make you good to go for future comments without the need for a delay.
Regarding “flotilla,” I’ve considered coining “flotilletta,” as it would be more accurately evocative. 🙂
However, “flotilla” has become pretty standardized in Western media for translating what Iran calls the numbered two-ship deployments, and it’s an editorial call to just go with that.
In naval operations terms, it’s of great interest that Iran pulled off a South Pacific transit to Brazil, without attracting more notoriety. Other navies with equally limited blue-water capabilities haven’t performed such a feat. There’s no good comparison to say what I’d be doing in Iran’s place, as blue-water navies have been setting up prior infrastructures to support global deployments for the last 200 years, rather than traveling like explorers in the age of sail. (E.g., contracting coaling stations across the globe in the steam age, as the Royal Navy, USN, Dutch, French, etc did.)
The current Iranian navy has just done the outbound leg of a global deployment on a different basis, and in general is evidently seeking to maintain secrecy and misdirection about it. Probably had help from China with it (buying fuel and stores somewhere between Jakarta and Rio). Data points to think with.