RogerBW's Blog

I've been playing with Flightgear again, now with a decent joystick and rudder pedals.

(I got my hardware purchase in just before all joysticks and pedals vanished from Amazon because of the new MS Flight Simulator release, which is nice.)

Given that I'm running Linux, MS Flight Simulator isn't an option (and given how much of the new version has to be rendered by remote machines it's effectively spyware too, if only in terms of the general area you're flying in, though I suppose most gamers are used to much worse). X-Plane is still going and available for Linux, and I think I technically still own a copy, but it's still commercial, and many of the interesting aircraft are payware too. Flightgear is entirely free and open source, and so are all its add-ons.

Flightgear aims for realism in its flight models first, prettiness later, which suits me very well.

Here's an approach to Rayne Hall Farm airfield, near Braintree.

Not pretty. Nor is the modelling desperately precise; the airfield isn't really on a little lump of ground like that, but the modeller assumes that all airfields are flat. Here is what it actually looks like (looking from the other end, and with snow).

On the other hand, the aircraft cockpit is an accurate 3d model of the Cessna 337 I'm sim-flying, almost all of the switches work as they should, the flight dynamics are pretty faithful, and – OK, note where the plane is facing compared with the runway. That's not because I'm incompetent. Down near the base of the propeller disc, directly above the altimeter, you can see the windsock near this end of the runway. At this point my aircraft is actually moving directly towards the runway; the skewed angle is because I'm compensating for the crosswind, and I'm going to touch the runway at that same angle and have to put on a hard left rudder as the wheel contact changes my direction. That's the sort of thing I care about more than how accurate the airfield looks.

And that's the actual weather (not exact modelling but with the right wind, cloud cover, etc.) that was happening there on the morning when I was simming the flight.

FlightGear is also remarkably open and easy to interface with. I've been writing code to read the scenery files for airports, navigational aids, etc., and make them into overlays in the Viking GIS software, as well as to talk directly to the simulator and track my progress. So here's the track from that flight, overlaid with basic runway information (details taken from the simulator's database rather than OpenStreetMap that I'm using for orientation, so they don't quite match):

I was able to pick up the A120 on my way out of Andrewsfield, the previous airfield, then follow it by eye to the major road junction in Braintree, turn north, and look around for the Rayne Farm strip.

For something a bit more complex, here I'm about to start my descent across New Brunswick in a Cessna Citation X (I prefer the light business jets to the big airliners, because they can go to more interesting airfields) on my way into Boston. Black lines are high altitude airway routes, the labels are intersections and navigational transmitters, and the red line is my planned route. The code which generates my flightplan can dump it in Flightgear's native format for use by its routeing engine as well as in something that Viking can read.

This is a simulator, not a game – by which I don't mean to deprecate either, but simply to say that any challenges are ones you set yourself. There's no standard ladder of things to try; there's just you, the aircraft, and the world. (Yes, all right, multi-player flights are possible, but not on the big networks like VATSIM – essentially because Flightgear is open and everything else that talks to the VATSIM communications system is closed, so anything that would work with both Flightgear and VATSIM would allow bad actors to inject spurious data into VATSIM by means of a "fake" Flightgear.)

So my personal rules for keeping things interesting are:

• that I start at the nearest airport to where I live (which used to be London City, but is now Wycombe Air Park) and expand my range from there. I don't fly out of an airport until I've flown into it, though not necessarily in the same aircraft or always starting from the last place I landed.
• that I use current real time (though I'll allow myself some time acceleration on long flights while I'm basically just waiting for the autopilot to take me from waypoint to waypoint), and real weather unless I'm deliberately making it worse.
• that as far as I can find out about them I obey real-world airspace restrictions and procedures.