StrataWx vs Active Sky FS, row by row.
Two real-weather engines for Microsoft Flight Simulator 2024. Every row is either Active Sky FS's own published wording, attributed, or a statement that something is not in their published material. Where they are ahead, the second half of this page says so, at the same length.
The short version.
Three global models build every StrataWx column, a surface report is trusted by how far away it is rather than by whether it exists, Hybrid puts today's real winds under a sky you author, and Sandbox needs no connection at all. Their product page states that Active Sky FS cannot be used offline. They ship wake turbulence, voice weather and Navigraph, and theirs is the cheaper purchase.
Working offline
StrataWx
Sandbox flies with no connection at all.
Live and Historical read real observations, so they need the internet. Your licence renews online in the background, and if the connection drops, an activated PC keeps working for at least two days and up to seven.
Active Sky FS
Their product page states that it cannot be used offline.
Their requirements state that the online activation and login system requires an online connection. Check it on their page before you buy: it is the only place their terms are current.
Account and session terms
StrataWx
Three PCs at once.
One copy is active on up to three of your own PCs at the same time, managed from your StrataSim Shop library. Nothing in the app asks you to stay logged in while you fly.
Active Sky FS
Their product page states that one login per user account is permitted.
The same page states that you may install it on several machines, and that you may be logged in only once at a time. That is their published account policy, quoted as policy.
Hybrid
StrataWx
Today's real winds under a sky you author.
Hybrid lays the real wind, temperature and pressure under a ceiling, crosswind, chop and visibility you set by hand. Fly the approach you want, in the air that is actually out there.
Active Sky FS
Their product page lists Live, Custom and Historical weather, and a Passive depiction mode.
It does not list a mode that puts live winds under an authored sky. They do author weather: their page describes control of wind, cloud, precipitation, temperature and humidity in Preset mode, and custom weather areas drawn on a map.
Models behind a column
StrataWx
Three global models build every column.
GFS, ECMWF and ICON, at 11 pressure levels from 925 to 100 hPa, with their winds averaged as vectors. The app shows how closely the three agree.
Active Sky FS
Not published.
Their page describes weather built from METARs, TAFs, upper air data (GRIB), SIGMETs, AIRMETs and tropical storm data, without naming the models behind a column. That is a statement about their documentation, not their engine.
A field with no report
StrataWx
A METAR counts fully to 30 NM and fades to nothing by 140.
The fade is smooth, blending the reported surface wind into the models' surface wind as you leave the station behind, so a field with no report of its own never inherits a distant station's wind.
Active Sky FS
Not published.
No page or update post we have read documents how a surface report is trusted with distance from its station. Again: their documentation, not their engine.
Wind between grid points
StrataWx
The cruise wind drifts. It does not step.
Upper-air columns are blended between the surrounding grid points as wind vectors rather than as degrees, because averaging 350 and 010 as numbers gives 180, and blending them as vectors gives 000.
Active Sky FS
Not published.
Their material does not describe how columns are blended between grid points. This row makes no claim about their engine: it is a claim about ours, and you can check it in the sim.
Cloud transitions
StrataWx
Layers are tracked by identity.
A drifting base eases on the layer it already is, and a departing layer dissolves before it is dropped, at one of four speeds you choose, from Glacial to Fast.
Active Sky FS
Their notes for update 071726 describe improved cloud smoothing.
The same notes name edge cases where cloud layers may instantly transition or become corrupt, in a post dated 30 September 2026. They have smoothing of their own, so this is not a claim that we smooth and they do not.
Route files
StrataWx
Open a plan file you already have.
Load a SimBrief plan by username or Pilot ID, or open a .fms, .pln, .fpl, .lnmpln or .pnl file, and get the wind, temperature and hazards at every fix's planned altitude.
Active Sky FS
Their product page lists Navigraph data and SimBrief flight plan integration.
They integrate with more of the ecosystem than we do, and the next section says so. The narrow claim in this row is only that reading a file you already have needs no other account.
Every claim about Active Sky FS above is their own published wording, attributed, or a statement that something is not in their published material. Their pages were read on 6 November 2026. Every claim about StrataWx is a named mechanism in the shipping app.
Where Active Sky FS is ahead.
A comparison that only runs one way is an advertisement. Here is the other direction, at the same size. If one of these is the thing you need, buy theirs. We would rather you were happy than converted.
Wake turbulence
StrataWx
We do not ship it.
There is a wake model in our code with tests around it, and nothing in the shipping app uses it. Until that changes it is not a feature.
Active Sky FS
Their product page lists wake turbulence.
It describes customizable clear air turbulence, thermals, drafts and wake turbulence effects working in tandem with the simulator's own. That is shipping today.
Voice weather
StrataWx
Text, not voice.
StrataWx writes an ATIS for the field, with an information letter and a runway in use, and shows the real D-ATIS, VATSIM or IVAO broadcast where there is one. Nothing speaks it on the radio.
Active Sky FS
Voice briefings on your radio.
Their product page describes voice weather briefings and in-flight updates through a simulated ATIS, ASOS and Flight Watch service. We have no equivalent.
Second screen
StrataWx
No companion app on public release.
StrataWx is a desktop app and an in-sim panel. There is no phone or browser companion you can install today.
Active Sky FS
A web companion app.
Their product page lists a web companion app among the features that keep working in Passive mode.
An ecosystem around it
StrataWx
A local API, and nobody building on it yet.
StrataWx serves weather, the ATIS and route briefings on your own PC, and sends winds to a PMDG or iFly FMC. Apart from our own StrataFx, no product has been built against it.
Active Sky FS
An API other developers integrate with.
Their page states that advanced API features are available to everyone to integrate with Active Sky FS, and describes a PMDG wind data export and a universal common data export that other add-ons use.
Navigraph
StrataWx
No Navigraph integration.
StrataWx carries its own offline airport and runway database, so ICAO lookup, METAR placement and the runway in use need no data account. A different trade, not a better one.
Active Sky FS
Their product page lists Navigraph data integration.
If your flight bag is built around Navigraph, that is a convenience we do not offer.
Simulators covered
StrataWx
MSFS 2024 and MSFS 2020, and X-Plane 12 apart.
Each MSFS simulator has its own app, and StrataWx for X-Plane 12 is a separate product that is not compared on this page. Nothing for Prepar3D.
Active Sky FS
MSFS, plus products for X-Plane 12 and Prepar3D v6.
Their update posts cover Active Sky FS alongside Active Sky for X-Plane 12 and Active Sky for Prepar3D v6.
Years of history
StrataWx
Historical, from ERA5.
Historical rebuilds a past day from the ERA5 reanalysis archive, which trails real time by about five days. We make no claim here about how far back it reaches.
Active Sky FS
Hourly archives going back years.
Their product page describes Historical mode with hourly global archives for the past several years, currently seven and more, with playback.
The purchase
StrataWx
One time, priced per simulator.
Every update to a simulator you own is free, and adding the other MSFS simulator later is a cross-grade, never a second full purchase. What the difference buys is the eight rows above.
Active Sky FS
Theirs is the cheaper purchase.
One Active Sky FS covers MSFS 2020 or 2024, as their requirements list it. We do not print their price, because their store is the only place it is current.
What StrataWx cannot do in MSFS.
Three limits come from the simulator rather than from us. We have not checked how Active Sky FS handles any of them, so this section is about StrataWx only.
The sky is one preset.
Microsoft Flight Simulator exposes no writable weather, so StrataWx works by writing one weather state for the whole world: the sky over your wing is the sky two states away. How Active Sky FS depicts weather inside the simulator is not documented anywhere we have checked, and we make no claim about it.
Onboard radar cannot paint our cells.
No cell shape or position reaches the simulator: StrataWx sends one precipitation value for the whole sky. Some add-on aircraft respond to injected rain as a uniform intensity, and pilots have told us so, but we have not verified what any particular radar reads.
You can step back to the simulator's sky.
Set depiction to MSFS Live and StrataWx sends nothing, showing the real weather beside a sky the simulator draws itself. Their product page lists a Passive mode, so this is not a difference in either direction.
Is StrataWx cheaper than Active Sky FS?
No. Active Sky FS is the cheaper purchase, and one Active Sky FS covers both MSFS simulators. We do not print their price here, because their store is the only place it is current. What the difference buys: Hybrid, three named global models behind every column, a surface report trusted by its distance from the station, and Sandbox with no connection at all.
Can I run StrataWx and Active Sky FS at the same time?
Not at the same time. Two weather engines driving one simulator fight over its weather. You can keep both installed: StrataWx does not start while Active Sky FS is running, and if Active Sky FS starts afterwards, StrataWx warns you and offers to close it.
What does StrataWx do that Active Sky FS does not publish?
Four things. Hybrid, which lays today's real winds, temperature and pressure under a sky you author. Three named global models, GFS, ECMWF and ICON, behind every column. A METAR that counts fully within 30 NM and fades to nothing by 140, so a field with no report never inherits a distant station's wind. And Sandbox that flies with no connection, where their product page states that Active Sky FS cannot be used offline.
What does Active Sky FS do that StrataWx does not?
Wake turbulence, which they ship and we do not. Voice weather on the radio, where ours is written. A web companion app, and an API other developers integrate with. Navigraph. Products for X-Plane 12 and Prepar3D v6 as well as MSFS. Years of hourly historical archives. And theirs is the cheaper purchase. That list is here because you would find it anyway.
Sources and terms.
There is no numbered reference list on purpose: every row states its source inside the sentence. What Active Sky FS does comes from HiFi's own published pages, at hifisimtech.com, and what StrataWx does is a named mechanism in the shipping app.
Active Sky and Active Sky FS are trademarks of HiFi Technologies, Inc. StrataWx is an independent product, not affiliated with or endorsed by HiFi Technologies, Inc., Microsoft or Asobo Studio. Comparisons on this page are our reading of HiFi's published pages on the date shown, and either product's features and pricing can change: check their store before you buy. Last verified 6 November 2026.
Decided to try it?
From $29.99, once, on StrataSim Shop, and every update to a simulator you own is free. For Microsoft Flight Simulator 2024 or 2020, or X-Plane 12, on 64-bit Windows 10 or 11.