It’s unusual for me even to consider getting any watch that’s nothing like the traditional kind. So, when the opportunity presented itself to get something completely different from any watch I had before, I took it.
The result? A brilliant piece of engineering with an impressive list of features.
- Model – Promaster Sky CB5860-86E
- Material – 316L stainless steel
- Crystal – Flat sapphire with ARC
- Diameter (bezel/12-6 axis) – 43mm
- Lug to lug – 50.5mm
- Lug width – 23mm
- WR rating – 200m
- Movement type – solar-powered quartz
- Calibre – Citizen E660 (in-house)
- Complications – Chronograph, perpetual calendar, alarm, power reserve indicator, world time/quick time zone switching, Radio-Controlled.
- Additional features – Slide rule/unit conversion
History, the Eco-Drive, and more
Citizen doesn’t need an introduction. At this point, combined with all its subsidiaries, it’s the largest watch manufacturer in the world. Not to mention the production of various electronic instruments – calculators, scales, and so on.
It started its life as a Swiss-Japanese joint venture in 1918 and has since then steadily grown. It was – along with Seiko – the pioneer of quartz and the leader in light-powered watches. There doesn’t seem to be a horological invention or kind of watch that Citizen hasn’t at least given a shot at – automatic chronographs, peripheral rotors, you name it.
Since 1995, Citizen’s key feature was – and still is – the Eco-Drive, which consists of a solar cell in the dial, coupled with a rechargeable battery. The system, on a conservative estimate, has a minimum life expectancy of 15 years. However, I’ve seen an early Eco-Drive going for 24 years and it didn’t look like it was going to stop any time soon.
The Promaster line
Citizen introduced the Promaster line-up in 1989, as a collection of purpose-built sports models. This included field watches, pilot’s watches, and ISO-compliant dive watches.
The line-up is mostly popular for its dive watches, however, the other genres did have a number of great models as well. The Sky sub-collection is known for “collaboration models” with some of the most famous demonstration squadrons, such as the US Navy’s Blue Angels and the RAF’s Red Arrows.
The Land sub-collection is famous for more or less bulletproof field watches like the Tough “Ray Mears” and its current successor, simply known as the Tough.
The watch in question is – at least in terms of design – a continuation of the Promaster Nighthawk, a time-only Promaster Sky equipped with a slide rule/unit converter, much like what you’d find in the Breitling Navitimer or its Sinn sibling.
Currently, the Nighthawk name rests with the ref. CA0295-58E, which is, admittedly, of the rather uninspired kind. With the cal. B612, which is basically a Miyota base with the Eco-Drive assembly, it has all of the base calibre’s faults such as the unbelievably slow reset. The reset in Citizen chronographs is slow and gummy on principle, however, that’s not the case with the Radio-Controlled chronograph movements or the E210 in the Promaster Tsuno “bullhead” chronograph.
This particular model seems to be only available in Europe. It has been introduced earlier this year, as a replacement for the previous generation, the AS4020 series, which used the cal. E670. The new calibre E660 improves on some of the functionality of its predecessor, however, given that Citizen usually does its best with the Radio-Controlled chronographs, the changes most likely cosmetic only.
In this watch, the dial is the real star of the show. Citizen is among the best when it comes to getting “busy dials” right.
Sure, you’ve got the scale for the slide rule there. A mix of city abbreviations and IATA airport codes, for particular time zones. Red/orange tabs for radio-sync indication and an alarm setting. The subdial at 3 o’clock is busier than any other part of this watch because it serves as a power reserve indicator, DST setting indicator, weekday hand, and chrono minute counter.
However, once you get used to what’s where, it becomes intuitive and easy to read.
The photos on the Citizen website suggested that the dial would be black. In reality, it isn’t. The rotating rehaut with the slide rule is a matte jet black, but the dial itself is a deep slate color with a sunray finish. Presumably due to the solar cell showing through, the subdials have a glossy dark brown effect to them, with an oil-pressed pattern of concentric circles in black here and there.
The photos on the Citizen website seem unfair in one more respect – they miserably fail at showing how deep and three-dimensional this dial really is.
All of the printing, at sufficiently intense artificial lighting, will cast a slight shadow on the surface below, as ultimately this whole thing has a solar cell underneath it. They won’t show you the way the subdials are recessed, nor the finishing of the silver rings around them. They won’t show you the finishing of the frames of the hour markers.
Speaking of hour markers, due to the overload of features, some of them have been clipped here and there, in order for the scales to fit. As a result, the markers at 2 and 4 are missing a frame, they’re just…two white strips. When I saw that, I thought that they’ll be just dark blotches at night, as they’re likely not lumed at all… I was horribly wrong.
Citizen, even though having clipped them to a minimum, made sure they’re properly lumed.
The lume in this watch is really good. In the usual Citizen manner, the Super-LumiNova has a bright, greenish-blue glow to it. As the glow fades, it loses the blue tint to a more ordinary green. The hour markers and the sword hands on this one have been filled with it generously.
While it doesn’t stay torch-like for too long, the glow lasts through the night, and in the absence of artificial light, you’re unlikely to not being able to read the time.
This watch is a pleasure to operate. The E660 has more features than I could possibly need, although if not for the quick time zone switching, it wouldn’t have more than I could actually use. Oddly enough, even the 24h display at 9 o’clock is useful here.
The subdial at 6 o’clock indicates the currently selected mode/complication. TME is the basic time and date display, CHR – chronograph, ALM – alarm, and SET – well, that’s just the mode for adjusting the time and date manually. Assuming that the watch won’t be kept in the dark long enough for it to run short on power, you’re unlikely to need the SET mode more than once.
While the chronograph is a useful tool, especially in the kitchen, I’d say the most practical feature of this one is the perpetual calendar. Reckon that’s what makes it the true “set and forget” kind of watch.
The subdial at 3 o’clock happens to be the 60-minute chrono counter, power reserve display, day of the week, or it tells you the current summertime (SMT/DST) setting.
The way the chrono works here is really good. The reset is slower than the current generation of Swiss ETA quartz chronographs, but it beats the Miyota-based B6XX series by a mile. Seeing the chrono seconds hand crawl back to 12 in the B6XX series is annoying, that’s not to say depressing.
If I had to name any flaw here, it’s that it operates for 60 minutes only, and lacks an hour counter. Once 60 minutes have passed, the chronograph will automatically stop and reset. No good if you’re timing some dish that takes more than that to cook. You’d be better off using the alarm function.
The chronograph here also serves as a kind of power-saving mode. Once the watch is in CHR mode, the seconds hand just stands still, the alarm’s off, and the watch does not attempt to synchronize. If you intend to leave the watch in a drawer for months (why’d you want to, though?), you want to leave it in that mode.
The alarm complication takes time to operate. When you activate the function, the hour and minute hands will set themselves to the last alarm setting, which means that sometimes they’ll have to cycle more than 23 hours forward. You can’t start setting the alarm before they complete that move to the last alarm setting.
Perhaps it could be better, but it’s not bad. I’ve used this one to wake myself up. It worked. That’s all an alarm needs to do.
Once you’ve activated the alarm, it repeats itself every day, except if the watch is in CHR mode. I wouldn’t rely too much on it as something to wake you up, though. It works for me, but I’m a light sleeper. For those sleeping like a log, this might be too quiet.
The alarm, as well as the SET mode, are where the 24h indicator comes in handy. I never thought I’d ever say that of this complication, which on principle I consider beyond useless. With time zone switching, there’s some use for it after all. I guess it’s a matter of what complications the 24h display is coupled with.
The finicky Radio-Control
As long as you’re within range of any of the atomic clocks with a radio transmitter, the Radio-Controlled feature will take care of any inaccuracies, setting the watch automatically to the most accurate reference time, twice per day.
One thing I don’t like about how the Radio-Controlled feature operates is that when it engages at 2AM and 2PM, the watch enters something of a bizarre power-saving mode, and the minute hand moves in substantially larger (2-minute) increments. When the signal has been received, the seconds hand will point at the OK position on the dial, the watch will do a slight wiggle of the hands, and set itself to the time received via the radio signal. When the signal hasn’t been received, it’ll point at NO, and set itself to the time it’s been keeping so far.
If you’re not sure the watch has successfully received the radio signal, it only takes pressing one button for the seconds hand to tell you that. If it’s a NO, you can synchronize it manually. You’ll probably need that – the Radio-Controlled system can be picky about the signal strength at the time of synchronization. If the watch is near an active stereo, mobile phone, or a Wi-Fi router, chances are high that the watch won’t sync because of interference.
One massive limitation of the Radio-Controlled feature is its range. The signal station chart in the manual shows how little places there are, where the watch can pick up a signal.
So, like all radio-sync watches, this one doesn’t like Australia and New Zealand. No reception there. Most of Europe is covered, but the signal supposedly won’t reach Athens. So, you’re in a sync signal black hole if you’re anywhere between the eastern edge of Belarus and the edge of a 1500 km radius from Beijing. That sucks!
Furthermore, if you’re in the middle of the USA, your watch – in theory – won’t pick up the signal from the atomic clocks on either coast. If you live on Midway, or in Honolulu, your Citizen won’t have anything to sync with, either.
If you’re in Anchorage, Alaska, you’re out of luck.
South America? Nope.
Africa? Out of any range. Azores or the Canary Islands? Nada.
But hey, Japan’s got bullet trains. So, Japan’s covered.
It’s not Citizen’s fault, they can’t possibly compensate for the range of the atomic clocks’ transmitters.
The issue of atomic clocks’ signal range is the same for any radio-sync watch – it doesn’t matter if we’re talking about Citizen, Seiko, Casio, or Junghans. Citizen’s Radio-Controlled tech isn’t at fault here.
The only downside that you might experience is that you can’t get it to stop in order to have it synchronized to a reference time of choice.
The successor to the Radio-Controlled system, the Satellite Wave, works just about everywhere – at least if you’re in range of a GPS satellite because the SW Citizens are synced via a satellite signal from the GPS satellite grid. The downside? Satellite Wave models cost two or three times what a Radio-Controlled one does.
The case (and how it wears)
The first thing I can say of this Promaster’s case is that it’s bulky. For one, it’s thick, at 14mm. A lot of that is due to the tall slide rule rehaut, although the handstack is on the tall side as well. The thickness and heft of this massive chunk of steel are nicely distributed by the flat and broad case back, which does a good job of bringing the center of gravity slightly lower.
About the general dimensions, I saw that the AS4020 and the CB5860 are listed as 46mm…which they are and aren’t. The bezel, and therefore the measurement along the 12-6 o’clock axis is 43mm. You’ll measure 46mm if you measure it across, from the crown and pusher guards at 1-3 o’clock to the slide rule’s crown guards at 4.
From lug to lug, it’s about 50.5mm, which isn’t little, but by my standards, that’s far from too much.
The broad stance of the case also has something to do with the lug width, which in this case is a horribly impractical 23mm.
Most of the case is finely brushed, except for the matte/sandblasted pushers and their tubes. And, of course, the polished bezel with a checkered pattern on the side, which goes along well with the barleycorn surface of the crowns. The main crown is signed with a polished symbol of the Promaster line on a matte background.
The edges of the case are beautifully finished. It could perhaps be nicer where the lugs meet the crown and pusher guards. However, with all that this watch has to offer, I can’t complain.
The case has a WR rating of 200m. None of the crowns are screw-down, the case back’s a press-in, so I wish I knew how they managed that. However, the Big Three of Japanese watch holdings – Seiko-Epson, Citizen, and Casio – are known for over-delivering in terms of WR. So I’m going to trust Citizen on that.
The thing that I immediately noticed – it’s heavy. Solid end links, and thick, full links.
Even though the structure of the bracelet appears complex, it isn’t. It’s made of one-piece links, held together by split-end pins. Speaking of split-end pins, I can’t possibly thank Citizen enough for that. Their bracelets usually have the old pin-and-sleeve system, which isn’t bad, but it’s a nightmare to adjust it.
The finishing is really good here – mostly brushed, but the thinner rows have each faux-link decorated with a contrast finish, with the line between the brushing and polishing being at the peak of each. So, it’s brushed, but with a subtle glint of polishing here and there. It looks great.
I wish the links were a bit tighter, because they’ve pulled a hair from my wrist.
On the outside, the clasp is a bit uninspired – however, inside it’s a well-designed, milled clasp. The twin-trigger release works smoothly. The safety latch closes up tightly, not allowing for opening the clasp accidentally.
If you don’t like the bracelet, this watch also comes in two versions on a leather strap with a deployant clasp. However, if you want this particular dial paired with a strap, you’d have to order a strap from one of the other references, as they have an entirely different color scheme of the dial. This particular dial only comes in versions on a bracelet, either in steel or Citizen’s exclusive Super-Titanium alloy.
The one thing I really don’t like about this watch is the lug width. There are more and more straps for odd lug widths out there, but 23mm is so very uncommon that aftermarket suppliers don’t bother to make straps for it. Some do, but you hardly have any choice. If you’d want to wear it on a canvas strap, a NATO, or a “Marine Nationale,” you’ll need to squeeze in a 24mm strap. That’s just the way it is.
All in all…
This is simply a reliable daily beater. Unfortunately, it has its limitations. Its capacity for synchronizing with atomic clocks is limited to just a few areas in the world. Each area has a radius of about 1500 km. Anywhere else, it’s as accurate as any ordinary quartz.
The complications that it has are useful. The alarm, the chrono, and most importantly, the perpetual calendar. If you don’t let this watch run out of energy, you’re in no need of setting the calendar as long as the Eco-Drive assembly keeps charging and powering the watch. Which is at least 15 years of not bothering to set it. That’s seriously hard to beat.
Of course, if not for the slide rule, which you’re probably not going to use unless you’re a pilot, the same functions can be found in the Casio G-Shock GW-M5610 series. However, that’s a completely different kind of watch, so it might not be an attractive alternative.
This watch would really make sense in titanium, not that it doesn’t in steel. Of course, there is such a version, but I chose the one that was available to me, the steel one. There’s nothing wrong with this one in steel, but I’d strongly advise trying on both steel and titanium before you buy it.
If your only shot at owning one of these is finding one online from the EU, titanium is probably your safest bet. I’m OK with the size and heft of this watch in its steel version, but that doesn’t mean that you’ll find it comfortable. The steel version retails for 499 EUR, which isn’t that much for what it has to offer.
The titanium version, CB5850-80E, has a retail price of 595 EUR. If capabilities and specs are your focus, and you don’t care about all the Switzerland vs. Japan nonsense, this one’s a good option.
These models are available at most ADs in the EU. I suppose that if you live in the US, your best bet is to find a deal on it on Chrono24.
What do you think of this Citizen Promaster Sky? Let me know in the comments below.
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