Asynchronous Loadout / Inverted Flight / Roll

[FoxxyTrotty]

Hi,

 

This is a physics issue, nothing major, and hopefully easy to resolve in a future patch. It is likely something people have noticed when doing various bombing missions, especially in the harrier and F18, where straight and level flight and lazy turnarounds are not possible.

 

I have attached an simple diagram to showcase a typical example, and this physics issue does affect all DCS modules (afaik).

 

When flying straight/level and balanced, all is well, then if you drop a bomb off the eg right pod, the heavier loadout on the left pod, and increased air friction on the left pod, will cause a force to roll the aircraft to the left. To prevent this from happening, the pilot adds some pressure right, to the aileron controls, and the forces are cancelled and level flight can continue. (a seasoned player would likely "trim this out" if the opposite munition were not moments from being fired/dropped).

 

(so far so good)

 

Often when over groups of targets, certain aircrafts and terrain, inverted flight may occur to line up for another shot, evade AAA/SAM and keeping within G limits, terrain masking etcetc

 

(here is where the issue is)

 

If aircraft were to fly completely inverted, the right pylon that dropped the bomb, is now on the left side, and the left, heavier pylon with remaining bomb, is now on the right (relative to the direction of travel). The heavier wing (bomb), with increased drag, should now create a downwards (gravity & air friction) force, causing the aircraft to roll the opposite way (as it's inverted).... The neutral point (where the forces cancel out, without pilot input) would be somewhere close to a 90' roll, with the heavier side of the aircraft leaning appx 90' into the ground.

 

(i get it, the exact angle would depend on centre of gravity and entire aerodynamic situation, speed, pressure etc probably too complex to be simulated in DCS, but 90' down would be an easy "close enough" solution)

 

shared image below - the arrows indicate direction of force (roll axis only)

 

 

I hope people can understand what I have attempted to describe and showcase here, my bad if not!

[Frederf]

You may think I'm crazy but it's possible that it's correct to always have a roll tendency in the same direction all the time. I remember reading such a discussion and while it didn't seem right at first.

 

I think I sort of remember. Lift is always pulling up from the middle of the plane and the mass is not equal. So the natural tendency is for the airplane to rotate around this center of mass.

 

So inverted doesn't matter but it must depend on the lift vector direction. If you fly -1G inverted level flight yes the tendency is for the heavy wing to sink. But with 1G flight where lift vector is directed toward the top side of the airplane it will fly a spiral corkscrew forever even if it turns upside down.