Flightle
Flightle is a small-scale 2D sidescrolling flight simulator you play in your web browser. Your objective is to land safely as close to the destination as possible, within the scheduled arrival time, with minimal fuel consumption.
The game is in play testing of the basic concept, with an unlimited number of missions per day. A new mission is generated each time the page is loaded. Whenever I decide to polish the game further, it will receive a technical overhaul, more gameplay elements will be added, graphics and sound may get an improvement, and it will be limited to a fixed mission per day.
While the ui is designed such that it should be usable on mobile, touch input is currently not supported. If I get around to the technical overhaul, support for touch input is a high priority.
To get into the air, you need to do three things:
To land, do the opposite:
As simple as it sounds, you might find yourself crashing a fair bit before you get into it. It helps to be smooth with the controls, and be mindful that the primary threat is the ground.
It can be dangerous to fly low and visually look for when the destination is near. Fortunately, your plane is equipped with two instruments to help you navigate to the destination.
When you start, the destination is to the right. The dme window tells you how far to the right, in nautical miles. Note that dme is based on radio signals from a ground transmitter, meaning even if you're laterally right over the destination, if you're overflying it at 0.7 miles altitude the dme window will read 0.7 as its lowest value. Once the dme starts reading negative values, you have missed the destination.
When you are within one mile of the destination, the glideslope (papi) lights will become visible on your control panel. These give you an idea of how quickly you need to descend to arrive at the destination. If the lights are all white, you are too high and will need to descend faster. If the lights are all red, you are too low and will need to descend slower. If there are two white and two red lights, you are on a 5 degree glideslope and you should use pitch and throttle to try to maintain the same glide slope down to the destination, keeping the papi indication showing two white and two red.
The "Scheduled arrival" clock is not a distance indication, it just tells you how close you are to getting penalties for lateness.
If you pass the destination and the plane is in a safe condition (i.e. no unnatural pitch attitude, well clear of terrain, enough fuel remaining) the "Go around!" button becomes available.
Going around gives you a second chance at the landing, at the cost of some time and fuel. It does this by transporting you back to before the destination, and automatically configures your plane for a somewhat stable approach. (Though you might still need to make some adjustments, this hints at a way to make landing easier: deliberately pass the destination and then perform an automatic go-around. If you think the approach is difficult and you have time and fuel to spare, that's a completely valid way to make life simpler.)
If you have passed the destination but have insufficient fuel to go around, your best option is to try to land the plane on the ground as soon as safely possible. There is no penalty for landing in the wilderness other than the fact that you by definition have ended up further from the destination. (Except water. Water landings count as crashes.)
Your score is based on three things:
These are combined into a score between 0 and 10.
The window marked CAUTION can display two warnings:
STALL: You are going too slow for your wings to generate lift.
The recovery manoeuvre is to pitch down immediately to exchange altitude for speed and only when your airspeed has increased try pitching up again. If you stall very close to the ground, that's fine – it's called landing. If you stall somewhat close to the ground, you're probably screwed.
To prevent stalling, monitor your airspeed, always. Especially during low-speed flight.
TERRAIN: You are fewer than 20 seconds from flying into the ground.
The recovery manoeuvre is to pitch up and set throttles to 100 % immediately.
The airspeed of an airplane is, to a first approximation, controlled by pitch. Nose-up flight is slow flight, and nose-down flight is fast flight. The vertical speed (climb or descent rate) of an airplane is, to a first approximation, controlled by throttle. High throttle induces a climb, and low throttle causes the plane to descend.
To achieve stable level flight, maintain a pitch attitude that gives you the airspeed you desire, and then adjust the throttle to get close to zero vertical speed. To decrease speed, you may have to adjust pitch and throttle simultaneously to get back to level flight. This is because the efficiency of the wings change with varying airspeed. (Some airspeeds require less throttle to achieve the same degree of lift.)
You may notice that you sometimes have to fight against your airplane to keep its nose pointing where you want it. This is because the plane is trimmed for a specific airspeed, and it wants to return to that.
Use the Trim control to adjust which airspeed the plane wants to return to. (The unit of trim is degrees, which might surprise you, but this is because you're really trimming for a specific angle of attack, and airspeed is a good approximation for that. See "More Reading" if you want to understand this and not just use it.) Once you have trimmed your airplane for straight and level flight, you will basically be able to go make a coffee and come back to it and nothing should have changed. (But don't actually do that, because winds and other environmental changes can upset the trajectory you intended.)
If you want to learn more about how to fly – even if you're just a little curious – I strongly recommend See How It Flies by Denker. For this game in particular, chapters 1, 2, 4, and 5 are relevant. The flight model is not really advanced enough to make most of chapters 6 and 7 useful.