I’ve been mulling this around a lot. After writing 40 reviews of addons for Microsoft Flight Simulator and having been around this industry (and the gaming industry in general) for about 20 years, I’ve picked up a few things that can set apart great airport addons from the good and below.
So I decided to share that experience, hoping that it’s useful to someone. Of course, this is more targeted to the many less experienced developers out there, who perhaps have started with MSFS. If you’re FlyTampa, Drzewiecki Design, Flightbeam, or one of the other top-tier devs that have been around for a long time, I probably won’t say much that’ll sound new to you. You know better than I do. But hey, if you find anything that’s useful, great.
Of course, this is a personal point of view and nothing in my resume changes that, so it doesn’t have absolute value. If anyone else has any further feedback (or thinks I’m horribly wrong with something), feel free to add your own view below. The more we have, the more useful it’ll be for people working on airports.
I hope this doesn’t sound too pretentious or patronizing, but remember nothing here is mandatory. It’s simply feedback put together with the genuine aim of trying to help (I’m proud like the next simmer, but I wouldn’t spend 2 hours after an 11-hour work day writing this stuff just to make myself look like I know better, I promise), and by helping you make better products, I help myself (and hopefully other customers) enjoy better products. Everyone wins. 
- Don’t underestimate the importance of research
If your airport has superb modeling and texturing, but it’s out of date or incorrect in its reproduction, it loses half its value.
Too many times, while reviewing an airport, a couple of hours of research revealed bits that were out of date or simply not correct. If I can find it, you can as well.
This is true when converting scenery you have made for other flight simulators as well. The issue of outdated details is especially serious in this category. Too many developers just assume that in the months or years since the previous release the airport can’t have changed that much and they can get away with it.
This is a very risky assumption. Especially now with COVID reducing traffic, many airports have started extensive renovation projects, if they hadn’t already started before the pandemic due to the boom of air traffic. Always assume something relevant may have changed and refresh your research before you start the conversion.
- Don’t assume that Google Maps is up to date
Google Maps is certainly a decent resource to see the general layout of an airport, but it’s not always up to date. As a matter of fact, for many areas of the world, it can be years out of date.
At times (in my experience more or less half of the time) Bing is actually more up to date than Google Maps.
How do you find out? Unfortunately, finding the date of aerial photography on both Google and Bing has become really challenging. A trick is looking as what’s under construction. If something is being built, obviously the source with the building in a more advanced state (or completed) is more recent.
If no obvious hint is available, you need to cross-reference with other sources. Flight videos on Youtube and pictures on social media (Instagram, Twitter, and so forth) can help identify discrepancies and find out which source is the best.
- Don’t solely rely on Google and Bing anyway
While it may be tempting to use Google or Bing as your sole source of information, it’s risky, unless you can absolutely date the source and be sure that it’s very recent.
Again, flight videos on YouTube and pictures on social media are very useful, because they’re usually dated and they also offer extremely precious additional perspectives and angles on top of the top-down.
Of course, nothing is better than a direct visit (or many) to the airport if the possibility exists. If it doesn’t, trying to get in contact with a local enthusiast and send them to grab photos and footage is also a great option (you can offer them a percentage on sales or some other sort of compensation. They’ll save you a LOT of research time, and that’s worth money), and you can always call the airport itself. The worst that can happen is that they tell you they don’t have time for you. At least you tried.
- If you don’t understand the language, ask for help
As someone fluent in Japanese, I can’t count the times in which I’ve seen Japanese airports with incorrect signage (or skipped signage) because the developer could not read said signs.
The same goes with any other language that may be unfamiliar to you. Find someone fluent (or at least somewhat proficient) in the language to check your signage or simply to provide you with a transcript.
A transcript will help a ton to create legible signage (unlike simply photo sourcing, which is often hardly legible if at all), even more so for 3D signs.
This will save you a lot of time and headaches. It’s a lot easier to have someone sending you “那覇空港 国内線” neatly written so that you can copy and paste it on Photoshop than having to squint on photographic reference and possibly getting it wrong. If you really love photo sourcing your signs, you can at least use the transcript to clean things up and improve legibility.
On top of that, a translator (doesn’t need to be a professional) can also help you find and read sources in the native language.
If you search “那覇空港” you’ll find a ton of sources that you’d never find simply by searching “Naha Airport.” If anyone is wondering, I’m not aware of anyone doing Naha Airport. I’m just using it as a random example (and wishful thinking 
). Incidentally, if you do need help with Japanese, feel free to drop me a line. I’ll gladly help you for free.
Of course, if you really can’t find anyone who knows the language, at least doing your own research in that language (Wikipedia will usually tell you the name of an airport in its native language) helps.
- Get yourself a Navigraph subscription
… Or a similar source of detailed charts. Having the detailed charts of the airport you’re working on helps enormously. This isn’t just related to approaches, SIDs and STARS (incidentally, make sure those are correct, especially if you’re relying on default data), but Navigraph also provides you with important information about parking positions/gates, taxiways (and their labels), lighting systems, and even construction and renovation work.
I can understand it’s not free (unless you can find a free alternative) but time is money, and this saves you a lot of time.
- Test your approaches
Few things leave a bad impression as setting yourself on an ILS and discovering that it’s offset by tens of feet, and it happens way too much. At times it makes you wonder whether the airport creator actually tested it at all, or they simply made sure it looked good.
Of course, this extends to the fact that you should test everything, from taxiways to ATC. If you can, get yourself a group of beta testers. Even just 2-3 can help a starting developer a lot, but of course, the more you can get, the better.
Incidentally, while testing your approaches, also make sure that the PAPI/VASI are correctly calibrated.
- Include custom jetways
The cases in which the real jetways of an airport are absolutely identical to the default jetways provided by Microsoft Flight Simulator are very, very rare.
I’m aware that custom jetways can be daunting for starting developers, but I can guarantee this is something many of your customers will immediately look at.
When they see an airport listed on SimMarket and you have “custom jetways” listed and they’re visible (and good looking) in the pictures, that immediately puts said airport in a higher tier compared to those made with default jetways. It’s inevitable, so it’s very much worth the additional effort.
- Don’t use default assets unless you really, really have to
Microsoft Flight Simulator comes with decent default assets, but they’re not great. They also very seldom really fit the real look of most airports.
Using them can help you cut corners, but won’t help your airport look good. They immediately stand out.
The exception to this is very small details like runway and taxiway lights, but at least, make sure the real ones don’t look completely different. If the discrepancy is too big, consider a custom model. I know, it’s tedious, but this kind of thing can, once more, set your airport aside from the average.
- Don’t focus exclusively on the main terminals
Quite a few times, I’ve noticed airports with great terminals and poor (or even default) hangars, fire stations, hotels, warehouses, and additional buildings.
While the terminals will likely be the focal point of your airports, remember that people will have to taxi around near the rest of the buildings as well.
Shifting one’s view from a beautiful terminal to mediocre buildings as you taxi around is rather off-putting.
- Textures for aprons, taxiways, and runways are important
This is again partly about not using default assets. The default textures for the ground are pretty awful and cartoony, so make your own.
Make sure your tarmac/asphalt textures are detailed and not repetitive, and that you apply the right weathering, patchwork, and staining to convey the age and real layout of the airport, and the many renovation works it has undergone.
Lines should not be too whole, bright, or cartoony (unless they’re very new in real life). They also should be weathered according to their age.
Pay attention to the rubber markings on the aiming zones of each runway. Some runways are used almost exclusively for take-offs, so they’ll have much fewer (or nearly none) markings because no aircraft is landing and braking on them.
If you’re using photosourced textures, make sure you don’t leave aircraft-shaped smudges in the places where you delete them, because they’re very noticeable, and they’re definitely not pretty.
- Consider using good ortophotos as your airport’s base
This isn’t always needed depending on where your airport is and the quality of Asobo’s aerials in the area, but more often than not, it really helps.
This is especially true in the not-so-rare cases in which there are discrepancies in the original aerials. I’ve seen airports in which there’s an obvious border line between aerials taken at different times literally crossing the runway. Don’t be that guy. 
- Terminal interiors yes or no?
Generally speaking, most of the feedback I see is that good terminal interiors help airports sell better. Nowadays, they’re considered almost a must by a large part of the audience.
You don’t need them to be incredibly fancy at the cost of performance (but if you can make them fancy and performing, why not?) and they don’t need to cover the whole airport, but strategically placed interiors help a lot.
If you do them, pay attention to possible discrepancies with opaque windows (it’s likely impossible to completely avoid this, but you can at least mitigate it), especially at night.
Alternatively, you can also use parallax shaders (also in combination with actually modeled interior), but make sure that those are placed in areas that don’t create weird effects if the camera moves. Usually, the farther from the ramps, the better.
- Tint your windows, but not too much
If you model terminal interiors, you’ll have to tint your windows slightly in order not to make them look unnatural. That being said, I’ve seen tints that ended up being really exaggerated. Try to keep the tint natural. You’re not making a church with stained glass.
A corollary of this is to look at how your transparent textures look in the mist. If they stand out too much, you may want to try to mitigate it. It’s not possible (I think) to completely remove this alpha issue, but you can help a bit. This applies to all textures with transparency, including some used for vegetation and more, so pay attention to those as well.
- Include the model for the VDGS
Whether MSFS supports the visual docking guidance systems (it does and it doesn’t. It requires going through loops to get it semi-functional, I guess) or not, you should still include the models of the VDGS in your airport. It looks a lot worse if you simply omit it.
- Modeled passengers yes or no?
This is an element that can enrich an airport, but isn’t exactly required. If you decide to use modeled passengers, make sure they don’t negatively influence performance.
If you can animate them, it’d be better, because static passengers can be a turnoff for some. If you can’t, at least place them in believable “scenes” and not just randomly. Make up stories as to why they would be there and what they’d be doing, and position your “people” according to that narrative.
- Static aircraft yes or no?
This is a contentious point. Some like them, some hate them. I’m of two minds.
First of all, do NOT use static aircraft if they don’t look good. Using poorly-textured free statics for FSX just to fill your apron isn’t going to be pretty.
If you have good static aircraft, first of all, don’t go overboard. I’ve seen a major international airport with literally 100 statics. I’ve counted them. That is way, way too many.
Secondly, make them an option. While we don’t have great AI traffic solutions right now, we’ll have them, and it’s easier to give the option to the get-go. On top of that, people who fly on VATSIM won’t love you if they’re instructed to go park inside one of your statics that they can’t remove.
I’m aware that the official marketplace does not allow options, but I hope it will one day soon. That being said, other vendors do allow for options, so please use them.
Static aircraft that wouldn’t be included in AI traffic and don’t occupy commonly used apron real estate are a much less controversial idea. Military aircraft are a good example, as they can give your mixed-use airport a more detailed look (similarly to coast guard, fire dept. and so forth).
- Don’t leave aircraft and vehicles painted on the ground
Many times you’ll see a good airport marred by aircraft and vehicles simply painted on the ortho used as the base. That’s incredibly off-putting. Cover them up with a texture and/or possibly similar parked vehicles.
- Don’t forget the fence!
Too many good airport developers forget the fence. Airports are high-security environments, so they’re fully fenced. The complete lack of a fence is a bit of a turn off for many.
If you have to, this is one of the fields in which you can resort to default assets, but I’d advise at least to use custom gates. Yes. Fences have gates. That’s another detail that shouldn’t be forgotten.
- Don’t neglect the landside
The landside portion of your airport may be much less visible from the aprons, bur it helps your creation by giving it character and creating iconic angles that people familiar with the real airport see a lot. A good landside is an added value that your customers will notice.
Also, make sure the roads at your entrance look like paved roads. Too many leave the base aerials for the sim without covering them with textures, with the results that they look more like dirt roads than an entrance to an airport. Not many (major) airports are served by dirt roads, so put some decent asphalt in there.
- Populate the area around the airport with scenery if possible
The experience with your airport isn’t limited to parking and taxiing within its borders. Approaches and departures are a thing as well, and reproducing the most visible buildings and landmarks under those routes is very important and a great added value for your airport, especially if you’re surrounded by autogen.
Highways, bridges, billboards, hotels, warehouses, malls, skyscrapers, monuments, public transportation, and more are all good examples.
Many airports have nearby warehouses and similar buildings with massive logos and writings on the roof. Those are iconic views on approach and shouldn’t be missed.
It’s always good practice to watch a few landing videos and try to identify what makes each approach unique and try to include that.
The more you add to your package, the more value it has.
On the other hand, please include all additional scenery (especially if it extends far away from the airport) in a separate installation folder. I know it’s sad if your customers may decide to not use some of your work, because of performance reasons or because they prefer to use a more extensive city pack, or whatever other reason. Yet, it’s good not to put them in the position of having to choose between using everything you offer and using nothing.
- Terraforming shouldn’t be optional
Aiprorts are rarely built on completely flat land, but chances are that your base will be a lot flatter than it should be.
Sloped runways are the obvious examples, but you should definitely make an effort to model things like mounds, ditches, underpasses, and so forth.
Another big example is airports on reclaimed land or artificial islands. The default ones are pretty flat, with the water at the same level as the terrain. This looks really bad and unrealistic.
Make sure your land is appropriately higher than the surrounding water and model the edge correctly. Add 3D rocks, concrete, and breakwaters to complete the effect and your airport will look 100% more impressive.
- Lighting is important
Make sure you try to reproduce the lighting of you airport as well as possible. Often airports will have older lights paired with newer ones, and those stand out. They also contribute to make the view more scenic at night.
Another element that is often forgotten are the red anti-collision lights on taller buildings. Don’t forget them if they’re present.
- Test your taxiways and runways with live AI
Again, while we don’t have good AI traffic solutions widespread at the moment, they’ll come, and preparing your airport for them is important (besides, it helps with default traffic as well).
Make sure Aircraft can land, take off, and taxi correctly to and from the gates and ramps. Common issues is aircraft reaching the runways and simply staying there until they disappear, airIrcraft disappearing on landing (usually means there’s an issue connecting the runways with the taxiways or that the ramps aren’t able to accommodate the aircraft’s size), aircraft getting stuck while taxiing, aircraft entering a runway when they should instead using taxiways, and aircraft not managing to land.
While AI traffic is not an exact science right now and a lot needs to be fixed by Asobo, there’s a lot that you can fo to make sure that at least the basic functionality is there.
- Don’t forget to test snow coverage and weather
If your airport is in a location where it snows at all, you should make sure snow coverage is good. It’s a turnoff when you approach an airport in the winter and it looks like it has a white pox.
On top of that, making sure your airport is prepared for the weather helps. Advanced things like not snowing/raining inside, droplets on the glass, and more, add value to your airport. I know it isn’t easy, but at least consider it. If that’s too much, at least avoid snow accumulation inside.
- Weathering is important
Speaking of weather, don’t forget weathering. If your textures are too clean, the airport will look like it’s made of plastic. Make sure surfaces show use, stains, and wear. This will help a lot in making your airport look natural and realistic, and less cartoony.
Good weathering paired with skillfully use of PBR can really help to make your airport look realistic.
- Research and add vehicle-only lanes
Vehicles speeding around the taxiways are a common plague. Many airports have vehicle-only lanes and you can definitely reproduce those in your scenery, much lessening the impact of stray vehicles on operations.
- Correctly label parking
Gates and ramps should be labeled accordingly. If you expect airliners to use a parking slot, call it a Gate (otherwise it won’t be used at all by ATC when the pilot asks taxi to the gate), if not, call it a ramp.
Also, label cargo and military ramps correctly. At the moment, this isn’t very much used, but it’s good to set your airport up correctly from the get go.
Research which kind of aircraft operate at the real airport and make sure you add gates sized to accommodate them. If your airport hists Airbus A380s but has no heavy gates, you have a problem.
- Add ground services
Make sure all ground services are available at every parking ramp that allows them. This includes the fuel trucks, that are so much neglected by developers. I know they’re basically cosmetic, but many of your customers enjoy immersion. That’s why they buy bespoke aiports to begin with.
- Be careful about vegetation
Make sure you place 3D grass where appropriate and that it doesn’t have too many pop-in issues. Study where vegetation is in the real airport, and for goodness’ sake, remove those spurious trees from the glideslope (or replace them with appropriately smaller ones). I guarantee they’re not there or they’re not that big in the real world.
- Pricing
This is, of course, a delicate topic, but I’ll still cover it in passing. Obviously, everyone should be compensated for their work (unless they feel very generous, but that’s a discussion for another day), so ultimately you should price an airport what you think your work is worth.
That being said, it helps to try to set yourself a units sales target and an hourly “wage” (or wages if more developers are involved).
Multiply that hourly wage for the hours you’ve worked (Yes. You should log them), and then divide them by the number of copies you expect to sell. That’s the minimum price you can ask to “break even” (in case you manage to match your sales target, of course).
For instance, if I decide I should pay myself $15 an hour, and I worked on an airport 100 hours, my “budget” is $1,800. If I expect to sell 150 copies of my airport, that means I’ll break even by charging $17.2 or more (factoring in the 30% markup that’s gonna be charged by a lot of marketplaces. Of course, you need to adapt this depending on where you sell and how much they want of your gains)
This doesn’t mean you should necessarily charge that. But it’ll give you a baseline to decide your pricing.
I know it’s tempting to look at other airport and simply do what they do, but in my experience talking to a lot of developers, trying to undercut the competition at least a bit helps a lot in achieving semi-esponential growth in sales.
Microsoft Flight Simulator is a popular sim, so there’s definitely room for charging a bit less to sell much more.
Especially, pay attention to psychological barriers. $9.99 is a good one for small airports, and $19.99 is good for bigger airports. I personally wouldn’t charge more than that unless it’s a very special case, but your mileage may vary. If you’re looking at $29.99, you’re pretty much locking yourself out of a LOT of sales and I would steer very clear from that kind of pricing.
On the flipside, while you may want to try to undercut the competition a bit, don’t undercut yourself. Always charge what makes you feel that your product isn’t valueless and what makes you feel happy. There’s always room for price drops and sales, but not much for price hikes.
Trying to sell your airport on as much popular stores as possible certainly helps. Seeking a partnership with Orbx, Aerosoft, or Contrail (or all of them) on top of selling on simmarket will definitely help you get your name out. On top of that, especially if you’re a new-ish developer, it’ll prompt more experienced peers to look at your add-on (they have to sell it, after all) and likely give you advice on where you should improve.
On top of that, they also provide you with installers and updating support that will save you some headaches.
Of course, the official marketplace is a great option if you manage to achieve partner status with MIcrosoft. It may take a long while to get it, but applying costs nothing.
This doesn’t mean you shouldn’t consider adding your own store where you don’t have to pay anyone a hosting fee, but a variety of sales environments will help a lot, and as you achieve a growing fanbase thanks to the visibility provided by other stores, more and more will buy on yours to support you.
Now, everyone else, the floor is yours, feel free to add whatever else you think can help 
