Particle system is seen as black from certain angles

Question

I created a particle system that should act as a spaceship's vehicle fire.

I've added it in a node loaded from a COLLADA file (made with Blender):

let engine = _spaceship.childNode(withName: "Engine", recursively: false)!

let engine_pSystem = SCNParticleSystem(named: "Engine", inDirectory: "art.scnassets")!
engine.addParticleSystem(engine_pSystem)

But the particle system looks black (literally like smoke) from certain angles, while from certain angles it looks normal (like in the scnp file of the image above). This video shows the problem: https://youtu.be/JvNe140C068

Answer 1

Try these settings, or similar to them...