Active Sky 2016 FSX: finished is not the same as abandoned

On 19 June 2026 a user called Kalorien posted on HiFi's own forum that his Active Sky window kept freezing on Windows 11 — no minimise, no close, nothing clickable, kill it in Task Manager and start again. He was running build 7968 of a weather engine released in July 2016, hooked to a simulator Microsoft shipped in 2006. One hour and forty-two minutes later HiFi's Daveo answered him. They went back and forth the next morning about firewall exclusions and ended with an invitation to open a support ticket.

Buried in that first post is the sentence that decides whether any of this matters: "The weather seems to be working." A weather engine is only a licence to talk to somebody else's servers. Switch the servers off and the box on your desktop becomes a very sophisticated way of displaying nothing. In June 2026, and again on AVSIM on 12 August 2026 when another user described AS16 on FSX:Steam Edition as making his flying "more accurate", HiFi's data was still arriving.

Now the part that matters more than the review. This is the FSX one. HiFi has, over the years, sold products called Active Sky Next, Active Sky 2016, Active Sky Cloud Art, Active Sky for P3Dv4, Active Sky P3D, Active Sky P3D v6, Active Sky XP, Active Sky XP 12 and Active Sky FS, and a person browsing a store in a hurry will buy the wrong one. Active Sky 2016 for FSX runs Microsoft Flight Simulator X — boxed with SP2 or Acceleration — and FSX:Steam Edition. That is the entire list. It does not run Prepar3D of any version; HiFi sold a separate AS16 for P3D v3, and everything from P3D v4 onward needs ASP3D or ASP6, which are different products with different licences. It does not touch X-Plane, which is Active Sky XP's job, and it has nothing to do with Active Sky FS, the MSFS 2020/2024 engine. It is not Active Sky Cloud Art either — that is the texture pack AS16 talks to, and it is sold separately. If you are on anything newer than FSX, close this tab; you want a different review.

Which leaves the actual question. HiFi last built AS16 for FSX on 25 October 2021. The trial site the developer's own 2016 announcement still tells you to visit, activesky16.com, no longer resolves in DNS. The AVSIM support forum for the product has seen two new threads since November 2024. Every visible signal says abandoned. And yet the servers run, the developer replies in under two hours, and simMarket has it at #14 on its all-time bestseller list. Finished and abandoned are not the same word, and the gap between them is worth exactly €29.99 to a very specific person.

This review reads 22 public sources: the developer's product, download, announcement and support pages, its own forum threads, four AVSIM threads spanning 2021 to August 2026, four store listings, three pieces of written coverage, one video walkthrough and simMarket's rating breakdown. Reddit is refused by everything in this environment, so the usual sentiment-at-a-glance check is missing; on a ten-year-old FSX add-on that matters less than it would on a new release, but it is missing all the same.

What you are actually buying

One SKU, one simulator family, one build. There is no boxed version, no upgrade path and no subscription.

Product	Active Sky 2016 (AS16) for FSX
Simulators	FSX with SP2 or Acceleration; FSX:Steam Edition. Nothing else
Current build	7968, dated 25 October 2021
Download	237.69 MB (simMarket), 235 MB (Just Flight)
Licence	One machine, mandatory online activation, ten automatic reactivations
Connection	Permanent internet connection required in normal use

Prices, on the day of writing:

Store	Price	Note
simMarket	€29.99	Terms state displayed prices "include the respectively applicable value added tax", which for an unresolved session is 0%. Shows USD 34.80 / GBP 25.67 as reference only
Just Flight	US$34.99	In stock
Flight1	US$34.99
Aerosoft	US$34.99	Shown "excl. VAT"
HiFi's own site	€29.99 listed	HiFi does not sell direct — the page links out to the four resellers above and warns that "Resellers may offer different base currency, policies and effective pricing"

Do not read that table as a price comparison. HiFi's €29.99 is a listed figure on a page with no checkout behind it, simMarket's €29.99 is tax-inclusive at whatever rate your session resolves to, and Aerosoft's $34.99 is explicitly before VAT. Nobody here is demonstrably cheaper than anybody else until you reach a checkout with your own country attached. What the table does show is that the price is uniform and has been for years — nobody is discounting this to clear it.

It is worth knowing where €29.99 sits historically. FSElite reported HiFi's launch pricing on 8 July 2016: €45.99 + VAT for AS16 FSX full, €27.99 + VAT as the upgrade for Active Sky Next owners. So today's full price is a third off launch, and roughly what an upgrade cost in 2016. That is a real reduction. It is also the only one you are getting.

Two alternatives a buyer should know about before committing. Active Sky Next, the previous generation, was sold as a Steam DLC for FSX:SE — that store page now reads "no longer available on the Steam store", so the cheap Steam route is closed, though HiFi still hosts an external B7968 update for anyone who owns it, noting that "Dovetail no longer supports FSX:SE addon/DLC updates". And Active Sky Cloud Art, €19.99, is the texture half of the pair; AS16 works with any cloud textures, but the real-time weather-driven texture swapping only happens with both installed. Budget for that if the screenshots are what sold you.

What the community consistently praises

The thing AS16 is repeatedly credited with is not prettiness. It is that it stops guessing. HiFi's own description of the data is the honest one — "global gridded weather data, global sigmets and airmets, global surface data and global aloft data … without relying strictly on METAR reports" — and users describe the result the same way across ten years. Murat on simMarket in June 2018: "Realistic and accurate weather simulation … It has no negative effect on simulation (freeze etc)." Artur in October 2019 called it the best weather engine for FSX and singled out its ability to push its weather data into PFPX and other planning tools. David in October 2020 said it "completely changes the sim". Charalampos, reviewing in October 2023, went further than most would: "The weather even better than MSFS2020."

The interpolation is the specific technical praise. FSX's own weather model snaps between stations; AS16 smooths cloud layers, wind, temperature and visibility between them, and that is what people mean when they say the sim stopped feeling like a slideshow of weather states. The turbulence modelling — jet-stream shear, wind-layer shear, wake turbulence, terrain-driven drafts — arrived properly with SP1 on 20 December 2016 and is the feature owners bring up unprompted.

Then the extras that were unusual for 2016 and are still not universal. XGauge WX gives you a working airborne weather radar in a sim that never had one. The historical playback lets you fly any date and time in the previous two years with the weather updating hour by hour as you go. The web companion app puts the whole interface on a tablet over your LAN. The API is why third-party aircraft and Roland's radar gauges could hook into it at all.

Performance is the quiet win. On a 2006-era simulator with a hard 32-bit memory ceiling, a weather engine that adds visible cost is a weather engine you uninstall. Guillermo in March 2019: "I have no LAG AT ALL." That complaint is conspicuously absent from the record.

What keeps coming up as a problem

The SimConnect bootstrap. Still open. AS16 injects into FSX through as_btstrp.dll, and when it goes wrong the sim closes. A buyer posted on AVSIM on 28 March 2024 that he had bought AS16 a month earlier and had not completed a single flight — "failed to send pws info: error reading from pipe. Internal error: 233" — after a clean Windows reinstall, a clean FSX reinstall, firewall exclusions and open ports. HiFi's Damian Clark replied three weeks later, pointed at the networked-PC setup as the likely cause, and drew a line: "We cannot provide networking technical support directly as it's outside the scope of our product." That is a defensible position and it is also a customer who paid and never flew. If you run FSX and Active Sky on separate machines, budget an evening.

The always-online dependency. Still open, and by design. AS16 will not work offline. A user in China posted on AVSIM on 26 March 2023 that without a VPN the application shows a no-connection message and closes itself; with a paid VPN it connects, and if the connection later drops, it warns and gives up. He asked whether AS16 could be made to work without internet. Nobody answered. The answer is no. Combined with one-machine activation and ten reactivations, this is a product that assumes HiFi will always be there.

The interface has not aged, and now it freezes. Still open. The map was criticised on the day of release — a Mudspike thread in early October 2016 had an ASN upgrader calling the new map "actually harder to interpret and read" than the one it replaced, and finding the overcast depiction overdone, "a wall of nothing" too often. Ten years later the UI complaint is that it locks up: Kalorien's 19 June 2026 report of a frozen, unclickable window on Windows 11 Pro requiring Task Manager. HiFi's Daveo said he had not had reports of it "for many many years" and suspected antivirus scanning. It remains untested and unresolved on the public record.

Weather at the wrong place when no flight plan is loaded. Mitigated. On 12 August 2026 an AVSIM user described AS16 repeatedly nagging him to load a flight plan mid-flight despite having loaded one. He got no replies. HiFi's own knowledge base carries an article on exactly this behaviour — weather at departure or destination not matching when a flight plan is not loaded — so the mechanism is documented even if the individual case never got an answer.

Third-party radar integration is inconsistent. Still open. Cathirame's simMarket review of 3 June 2021 rated it five stars and still noted "the PMDG's WXR seems not woring with this product, still troubleshooting". No public resolution exists.

The Windows 11 HTTP crash of autumn 2025. Fixed, and not HiFi's fault. Microsoft updates KB5065789 and KB5066835 broke network HTTP functionality for "all AS products". HiFi confirmed it publicly and posted on 18 October 2025 that Microsoft had pushed a corrected KB5066835 which resolved it. Assign the blame accurately: that one was Redmond's.

Performance and stability

The frame-rate question barely arises. Ten years of owner reports on a 32-bit simulator with no headroom to spare contain almost no complaints about AS16 costing performance, which for a weather engine is close to the highest praise available.

Stability is a different picture, and it splits cleanly. Where AS16 runs on one machine with FSX, exclusions set and antivirus told to leave it alone, it is boring in the way infrastructure should be. Where it is networked, or fighting a security suite, or on a Windows build Microsoft has just changed, it fails in ways that end flights: sim closures on as_btstrp.dll, a frozen interface, a self-terminating application when the connection drops.

The pattern in the record is that almost every current AS16 failure is an environment failure rather than a code failure — and that is precisely the problem with a build frozen on 25 October 2021. Environments keep moving. Windows 11 shipped its HTTP regression in 2025 and the fix came from Microsoft, not from HiFi, because there is no longer an AS16 team to ship one. HiFi did make a build specifically for FSX:SE's last public beta in October 2021, which was more than Dovetail managed. But that was the last time.

Who should buy it

The FSX or FSX:SE simmer who still flies weekly and has never had a proper weather engine. Buy it. Nothing else available for FSX in 2026 does what this does, the servers are demonstrably feeding it, and €29.99 for the difference between FSX's native weather and this is not a hard sum. Set your firewall exclusions before you fly, not after.

The Active Sky Next owner wondering whether to move up. Marginal, and it was marginal in 2016 — the Mudspike thread's most detailed assessment concluded the upgrade was worth it mainly to support the developer. The gains are real (SP1's shear turbulence, the radar gauge, historical playback) but you already have a working engine. If your ASN install is stable, keep it.

The offline flyer, or anyone on a locked-down or air-gapped machine. Do not buy it. This is the profile the product actively excludes. AS16 requires a live connection in normal use and shuts itself down without one, activation is mandatory and machine-bound, and there is no offline mode to negotiate for.

Anyone on Prepar3D, X-Plane or MSFS. Do not buy this SKU. It will not install into your simulator. You want ASP3D or ASP6, Active Sky XP 12, or Active Sky FS, and buying this one by mistake is the single most likely way to waste €29.99 on the HiFi catalogue.

The cautious buyer who wants to try before paying. You cannot, and you should factor that in. The 7-day trial HiFi advertised is gone — activesky16.com does not resolve — and simMarket's listing says in capitals "FSX VERSION ONLY - NO REFUNDS". Thirty euros, sight unseen, no way back. If that is intolerable, walk away; the product is good but the purchase is genuinely blind.

Where it stands today

The record on this product is unusually clean and unusually one-sided. simMarket shows twenty ratings: eighteen at five stars, one at four, one at three, nothing lower — a true mean of 4.85 against a displayed 5, and the most recent of them dated 2 January 2026. It sits at #14 on simMarket's all-time bestseller list. That is what a decade of quiet satisfaction looks like, and it is the reason the score below is not higher: a product this well-liked would ordinarily clear four.

It does not, because the score has to price in what a 2026 buyer is actually taking on. A build frozen since October 2021. A mandatory permanent connection to servers nobody has promised to keep running. A machine-bound licence with a finite reactivation count. No trial, no refund, and no successor to migrate to if FSX finally becomes unrunnable — HiFi's line moved to P3D, X-Plane and MSFS and left FSX behind, which is honest, but it means AS16 is a terminus rather than a step.

Against that, the two things that would actually kill it are not happening. HiFi shipped an ASFS beta on 12 August 2026 and answered an AS16 question on its own forum on 20 June 2026, and in January 2025 HiFi's founder personally read a customer's AS16 log export and replied inside 48 hours. The weather data is arriving. This is not a dead product being sold to the unwary. It is a finished product being sold at a fair price to a shrinking audience by a developer who still picks up the phone — and the honest advice is to buy it now, while all three of those remain true, or not at all.