TUAW Review: X-Plane 9 for iPhone / iPod touch

Flight simulator applications are not only great entertainment, but a good way for would-be pilots to hone their skills without burning fuel or booking time in a "real" flight simulator. X-Plane 9 from Laminar Research is currently the most impressive flight simulator for Mac, with hundreds of different types of planes, thousands of airports, and very realistic weather.

Laminar Research recently ported X-Plane 9 to the iPhone and iPod touch (click opens iTunes). While it doesn't have the extensive feature set of the Mac version, X-Plane 9 for iPhone and iPod touch is an impressive effort that shows off the sheer power of the iPhone and iPod touch both computationally and graphically.

The app is a slender 7 MB and as you'd guess, you're giving up a bit of the Mac version's capabilities with the iPhone port. Instead of the entire world, you now have a 1,600 square mile area centered near Innsbruck, Austria to fly around in. There's only one airport, four aircraft types, less accuracy in terms of the flight models, no cities to fly over, and no navigation aids such as VORs. Is X-Plane 9 still a worthy iPhone app? Read on...

Easy to fly

Even if you've never "flown" a flight simulator before, you can get the hang of flying X-Plane 9 for iPhone very quickly. The view is always in landscape mode, and the screen has a slider on either side of the screen to control the throttle (left) and flaps (right). For aircraft with retractable landing gear, two buttons appear in the center of the screen to raise/lower the gear and engage/disengage the brakes. With the Cessna 172, which has fixed landing gear, only the brake button appears.

Across the top of the screen is a row of buttons for controlling the view and set up the simulator (see screenshot below). The left-most button shows the heads-up display that you use to control your view important information, such as your throttle and flap settings, The next three buttons show external views of your aircraft in flight, while the right-most button provides access to settings. In case you're thinking that all of these buttons are going to block the view out of your virtual windshield, you're wrong -- they fade out of view and can be brought back up with a single tap on the screen.

Settings

What can you configure with the settings button (see screenshot below)? A lot. If you want to practice random flights, you can start off in the air cruising along in a fairly stable attitude. Want to practice takeoffs or landings? You can start X-Plane 9 on the runway, or in the air heading towards the runway on short or long final. The time of day can be set to daytime, sunset, sunrise, or night. Want to make flying a challenge? Dial up the wind speed, change the wind direction, and throw in some turbulence for fun. You can practice flying in various cloud conditions as well, vary the cloud base, turn on the rain, and take the visibility from clear to socked-in. Finally, you can vary the weight and location of the center of gravity for the aircraft to make it easier or more difficult to fly.

As the pilot, you have a choice of four aircraft -- the venerable Cessna 172, the sweet Columbia 400 (now a Cessna product), the Cirrus Vision single-engine jet, and the Ferrari of the skies, the Piaggio Avanti. Notice the aircraft that are grayed-out in the screenshot below? They're your other choices, while the Cirrus Vision is the current aircraft being flown.

You've picked your plane, set up the flying conditions, and you're ready to go. As you can imagine, X-Plane uses the iPhone's accelerometers to control the flight (I'm wishing that someone would come up with a "control yoke" that you could mount the iPhone in the middle of). If you're doing a takeoff simulation, you move your throttle slider up (indicating more power), give the aircraft some flaps if you'd like by moving the flap slider down, and then release the brakes. Once the airplane has picked up enough velocity, tilt your iPhone toward you to "pull back the stick" and bring the nose up. After your aircraft is climbing, you can raise the landing gear (if it has retractable gear), bring the flaps back to zero, and then start flying the aircraft around in the virtual world.

In flight

As you're flying, you tip the iPhone left or right to turn. Your heads-up display (see below) shows your airspeed, altitude, an artificial horizon with a flight path indicator, throttle and flap position indicators, and a compass. Some early users complained that they could never find the airport after taking off; there's a needle on the compass which always points to the airport so you can return for landing.

The external views that are available are a lot of fun. You can see things like your gear or flaps going up or down, and I like the chase view that allows you to move a virtual camera around the aircraft by dragging the screen or using the pinch in/out gestures to zoom in or out (see below).

When you're flying, the graphics are wonderful. The scenery looks very realistic as you fly over and around it, the landing lights next to the runway work as they should, and flying through a cloud layer is surprisingly similar to the actual experience. Of course, Laminar Research had to make this app as small as possible, so you can do things like make high-G maneuvers that would destroy a real airplane in flight.

Reviewer's Comments

The application doesn't appear to use too much of the iPhone's power, as I've flown the simulator for hours a few times without draining the battery. There are a few issues in this original 9.0 release (9.01 is apparently on the way). Those issues include not being able to put the iPhone to sleep while X-Plane is running, not remembering the conditions of your flight when interrupted by a phone call or when you want to stop using the sim for a while, program crashes while I was moving the camera around in an external view, and even the occasional crash (application, not aircraft) while starting the app that required a device reboot to fix.

As an interesting side note, I demonstrated X-Plane 9 to two people; a friend who is a professor of Aerospace Engineering and aircraft design, and my father, who was a flight simulator engineer for United Airlines for many years. Both of them agreed that for an application that is running on a phone, X-Plane 9 is amazing. It's a fun simulation, and can let you practice basic flying skills at any time and any place. Both were amazed with the graphics capabilities that Laminar Research built into X-Plane 9, and they felt that using the accelerometers in the iPhone to control the aircraft was brilliant.

Another fascinating thing about X-Plane 9 is that it was ported from the Mac version in about two weeks. Apple asked Laminar Research developer Austin Meyer if he could port the Mac app to iPhone before the September iPod event. The app was done in time, although it wasn't used at the event.

Conclusion

X-Plane 9 for iPhone / iPod touch isn't for everyone. If you're looking for a high-action game, look elsewhere. But if you are a fan of flight simulation software and would like to have the opportunity to "fly" anywhere you happen to be, X-Plane 9 is definitely worth the US$9.99 price tag. Austin Meyer has a reputation for constantly improving X-Plane 9 for Mac, so I'm confident that we'll see significant upgrades and bug fixes in the very near future.

I would like to see one addition to the application or the Laminar Research website, and that's a help file. There are some items on the heads-up display that don't have explanations anywhere -- I'm assuming that the Mach number is listed below the throttle setting and that the number under the flap setting indicates climb rate, but I'd rather know for sure. It would also be nice to have an auto-pilot "return to airport" feature that would fly you to the correct location and altitude to begin a safe landing.

My biggest problem with X-Plane 9 was that it was hard to put the iPhone down and write this review! It is a very addictive app for flight simulation enthusiasts and pilots. I'm also interested in getting the Mac version of the app now, as I'd really like to get better at my "flying". Well done, Laminar Research!

Update: X-Plane 9.01 showed up as an update within minutes of this post. Frame rates are about 25% higher to make for smoother animation, there's a calibration screen for the iPhone / iPod touch accelerometers, the interface has been made more readable and reorganized for more usability, and a quick reminder in the middle of the screen tells you to tap anywhere on the screen to see view and settings controls.