4. Flying: aircraft profile A, flight modes, RTH, battery
Translated from the Finnish manual (manual/fi); the Finnish text is authoritative.
Matches version: 0.1-dev (phase 1, 2026-10-26). Status: works; the figures come from the profile file game/aircraft/profile_a.tres and are being tuned with pilots.
Course of a flight
- Motors on (X or the radio switch): announcement Flight operations start, the home point is set at the aircraft's position.
- Take-off: throttle above the midpoint lifts the aircraft, or T does an automatic take-off to a hover at about 1.2 m. Announcement Take-off.
- Flight with the sticks (chapter 2). With the sticks centred the aircraft brakes and holds its position and height.
- Landing: throttle down over the home point or anywhere else. When descending below 10 m, announcement Landing; below 3 m the descent slows to 1 m/s; on touchdown, throttle down stops the motors (Landed, Flight operations end).
- Esc ends the flight and shows the summary (chapter 12 coming).
Flight modes
| Mode | Horizontal speed | Acceleration / braking | Tilt | Use |
|---|---|---|---|---|
| N (normal) | 16.8 m/s | 4 / 6 m/s² | 25° | default, search |
| S (sport) | 23 m/s | 7 / 9 m/s² | 35° | transits |
| C (cine) | 5 m/s | gentle | small | close observation |
Climb at most 6 m/s, descent 5 m/s, yaw 100°/s at full stick. Switch with F1/F2/F3 or the radio's three-position switch.
Limits
- Maximum altitude 100 m above the take-off point (the open category's 120 m is a hard ceiling). At the limit the climb stops gently and the HUD warns.
- Maximum distance 500 m from the home point; the same gentle stop. The limit is deliberately the same as the VLOS circle (chapter 6).
- The limits are scenario parameters; the instructor will be able to change them in a later version.
Return to home (RTH)
H starts it: the aircraft climbs to RTH altitude (60 m above the home point) if it is lower, flies home at no more than 12 m/s, lands on the home point and stops the motors. H again cancels the return and the aircraft stays hovering. RTH does not yet avoid obstacles: choose the altitude so that there are no trees higher than it on the route.
Battery
A full battery gives 36 minutes of hover in calm air. Flying forward, the body gives a little lift: at about 10 m/s the flight time is longest, 41 minutes; at the top speed of 23 m/s about 22 minutes. Climbing and wind use more (below). The HUD shows the percentage and an estimate of the remaining time at the current consumption. At 20 % the warning BATTERY LOW, RETURN, at 10 % BATTERY CRITICAL. With an empty battery the aircraft lands by itself. The effect of cold is not modelled yet.
Wind
The wind comes from the weather (FMI or set by hand, chapter 10) with its gusts and grows with height. The aircraft is heavy and stabilised: in GPS mode it holds its position in winds up to 15 m/s in every flight mode; only the part above that makes it drift, and even then the position hold slows the drift. In ATTI mode (below) the wind carries it fully.
| Wind at the aircraft | What happens |
|---|---|
| under 8 m/s | a steady ride |
| from 8 m/s | a bumpier ride: the hull rocks and bobs (up to about 4° and 0.3 m at 15 m/s); the gimbal keeps the camera steady, so the picture shows only the bobbing |
| from 10 m/s | warning high wind (the maker advises avoiding winds over 7–10 m/s) |
| from 12 m/s | the take-off and landing limit: land immediately and stop flying, repeated every minute; a take-off in such wind warns but is not blocked |
| from 15 m/s | the airframe's technical limit is exceeded: land immediately; the position hold starts to give |
Wind eats battery: in a 12 m/s wind the flight time is about 15–25 minutes depending on heading. Holding position about 20 min, downwind about 24 min, into the wind at 5 m/s ground speed about 16 min and at 8 m/s about 13 min. In a 5 m/s wind the difference is small (about 33 min of hover).
Other limits: operating temperature −20…50 °C (a warning at take-off and once in flight when the air is outside the range); protection IP55, so rain or sleet does not stop flying. Descending straight down at most 5 m/s, while flying forward 7 m/s. In calm air the aircraft holds its position with GPS to about ±1.5 m horizontally and ±0.5 m vertically, below 33 m with the downward vision system ±0.3 m / ±0.1 m.
Battery changes and flights (phase 4a)
A mission often takes more than one battery. Land at the launch site (no more than 12 m from the home point), stop the motors (X) and press B: the battery change takes 75 seconds of mission clock — a practised crew takes 60–90 s — and after that the battery is full. The motors cannot be started during the change. Every motor start opens a new numbered flight (Flight 1, Flight 2, …); take-offs, landings and battery changes are logged in the GPX as waypoints.
The mission clock does not stop for a battery change. The summary shows separately flight time (motors) and the operation span: from the first "Flight operations start" moment to the last "end" moment, battery changes included. The operation span is the time reported to the authority for compensation — a battery change does not break it. Pausing from the Esc menu, on the other hand, stops the clock, because pausing the exercise is not flight operations.
GPS interference and ATTI mode (phase 4d, drill switched on)
Satellite positioning can be disrupted — in Finland especially near the eastern border — and then the aircraft falls back to ATTI mode: it holds its height from air pressure, but not its position. In the simulator the interference is a drill that is off by default: on the planning map G switches it on, and then GPS is lost 3–8 minutes after the first take-off for 2–4 minutes (the moment is drawn from the scenario seed, so the same seed gives the same interference).
In ATTI mode: the HUD mode indicator turns into a red ATTI and a warning is shown on screen; with the sticks centred the aircraft does not hold its position but drifts with the wind (2–4 m/s blows during the interference); the distance limit does not work; RTH is not available — the aircraft must be flown home by sight (the home point H mark and the edge arrow help). Height hold works. When the interference ends, position hold returns ("GPS restored").
The purpose of the drill is the same as in real operations: notice the interference in time, stop the search, fly the aircraft back safely and report it.