Platform:
Android
Game Version:
3.7.0
Airport:
GRU & MCT
Description of the Bug:
TL;DR - At GRU, MCT & ZRH, DHC6F (and some STOL planes) take off too early and skip getting checked by the game to allow other aircraft to line up and take off.
With the introduction of the DHC6F in the recent 3.7.0 update, it became the aircraft with the shortest takeoff distance in the whole game, rotating only after 350m compared to the previous record holder, DHC6, at 800m. At GRU, unfortunately this short distance means that runway 10L becomes broken after DHC6F takes off from the runway.
Suppose the start point to be the point on the runway where the aircraft lines up and waits for takeoff clearance, the point of climb to be the point where the aircraft rotates and gains altitude (where then other aircraft on runway 10L can line up and takeoff, or aircraft can land on runway 10R), and the point of lineup to be the point passed by the aircraft taking off which then allows other aircraft to line up (but not takeoff).
As has been implemented in the game, the point of lineup must be positioned in front of all runway entrances, so that taxiways closer to the start point do not gain a time advantage and allow planes there to line up earlier, preventing farther entrances from building a departure queue.
The distance between the start point and the point of climb will hereafter be referred to as the takeoff distance, and the distance between the start point and the point of lineup will be referred to as the lineup distance.
In almost all cases at any airport, the lineup distance is shorter than the takeoff distance mostly because most aircraft require a relatively long distance before climbing. Furthermore, a good majority of airports enter the runway from one taxiway or otherwise taxiways that are adjacent and close to each other, and these taxiways are positioned near the threshold of the runway, so the point of lineup is not very far from the start point.
However at GRU, there are 2 taxiways being used for takeoff. Typically planes use taxiway G (the west/left one), but planes with runway category A & B use taxiway H (the east/right one). This means the point of lineup is positioned east of taxiway H farther away from the threshold.
However, taxiway H is not used for category A & B aircraft if they are parked at terminal 1, terminal cargo, or the west side of terminal 2A. Unfortunately DHC6F can only park at the mentioned terminals because they host the only cargo stands at the airport. This means DHC6F always needs to take off from taxiway G, resulting in a longer lineup distance.
Hence the lineup distance is longer than the takeoff distance. This is an exception to the typical behaviour of the other way around. Since the game only checks if other aircraft can line up after the point of lineup, DHC6F taking off so early means it never passes through the point of lineup on the surface of the runway. This results in the planes waiting to line up to be deadlocked, with the statuses still being “Runway occupied” even after the aircraft has disappeared after flying long enough.
Multiple ways to change the occupied status have been attempted but have failed, ultimately requiring a reloading of the airport. These ways include hiring and activating the departure controller, allowing planes from runway 10R to cross runway 10L, and landing a plane on runway 10R.
This could potentially be fixed if the code allows all waiting planes to line up after takeoff instead of after passing through the point of lineup. Alternatively though less desirably, the waiting planes should be allowed to line up after the departing plane has disappeared from the map.
This behaviour is also observed at MCT runway 26L, though this runway does not get softlocked because it is also used for landings unlike GRU runway 10L.
Steps to Reproduce:
This behaviour requires three preconditions:
- Multiple runway entry points for the runway, one located near the threshold, and the other(s) located relatively far away. These are GRU runway 10L and MCT runway 26L;
- Aircraft with a short takeoff distance. These are DHC6F (only aircraft for GRU) and L-410, DHC6 (unsure) & DH8A+DH8B (unsure) (for MCT);
- Said aircraft types are allowed to enter the runway from the entry near the threshold. These are taxiway G at GRU and taxiway E8 at MCT.
- Let the target aircraft pushback and taxi to the taxiways mentioned above, so that they may take off from the respective runways.
- Let any other aircraft go to the other entry taxiways, such as taxiway H at GRU and taxiway D7 at MCT. Preferably, there should be one aircraft behind the target aircraft so that it may wait at the same entry taxiway after the target aircraft has lined up on the runway.
- Let the targetaircraft take off from the runway.
- Observe the waiting planes at other taxiways after the target aircraft begins climbing, and also after the aircraft has disappeared after flying for long enough.
The waiting planes should not be able to have the option to line up on the runway indefinitely (once again except for MCT where 26L allows a plane to land which solves the softlock).
Screenshots or Videos (if available):
The video below shows DHC6F at GRU runway 10L taking off from the runway. Towards the end of the video (01:00), both the L410NGF (at taxiway G) and L410 (at taxiway H) are not given the option to line up and takeoff because the runway is falsely presumably occupied.
The video below shows DHC6F at MCT runway 26L taking off from the runway. At 00:46, the CRJ2 (at taxiway E8) does not have the option to takeoff for the same reasons above, even despite the DHC6F going past the point of lineup. Only after a plane is landed in the second half of the video, the planes were once again allowed to line up on the runway.
This video shows a DHC6F taking off from runway 32 by entering from taxiway H3. At 01:26, the E290 waiting to line up with the runway is unable to do so because of this bug. At 01:37, an AT43 attempting to line up from taxiway H2 is also unable to go ahead despite not being there during the DHC6F’s takeoff.
Additional Notes:
There is another bug with STOL aircraft passing taxiways where other aircraft cross the runway, and the crossing aircraft not being given the option to cross afterwards. The difference is that the crossing aircraft get the prompt to cross only after the STOL aircraft has disappeared from the map.