Northrop Grumman B-21 Raider (LRS-B)

[dark sidius]

Photographer Captures Cool Shot Of B-21 Raider Stealth Bomber During Test Flight

The Northrop Grumman B-21 Raider was chased by an F-16 from Edwards Air Force Base during its test flight when it was caught on camera. Following its

theaviationist.com

Not bad fake but real test flight...

 

[F119Doctor]

Interesting that the two engine B-21 contrail appear significantly lighter / narrower than the F-16 chase plane. Since the contrail is formed from freezing water vapor from the burning fuel, does this mean the B-21 is burning less fuel than the F-16 at this flight condition? This assumes they are at the same altitude and contrail conditions, which can change rapidly.

It could also mean that the shape of the nozzle is flattening the exhaust stream, making the contrail thinner top to bottom turns less visible. but you would think this would result in a wider, if fainter, contrail

 

[TomcatViP]

@F119Doctor : I think this is more related to the the lift. The jet expansion is fairly local at subsonic speed but the DelatP in the trailing wake freeze the moisture into contrail. Hence why a higher loaded wing would contrail more white than another one.

 

[Scott Kenny]

Interesting that the two engine B-21 contrail appear significantly lighter / narrower than the F-16 chase plane. Since the contrail is formed from freezing water vapor from the burning fuel, does this mean the B-21 is burning less fuel than the F-16 at this flight condition? This assumes they are at the same altitude and contrail conditions, which can change rapidly.

It could also mean that the shape of the nozzle is flattening the exhaust stream, making the contrail thinner top to bottom turns less visible. but you would think this would result in a wider, if fainter, contrail

My initial guess would be nozzle shape.

 

[Foo Fighter]

Jet engine emissions and vapor contrail reduction through
increased combustion efficiency with the aim to mitigate greenhouse gas emissions.

https://digitalcommons.georgiasouthern.edu/cgi/viewcontent.cgi?article=1782&context=honors-theses

 

[dark sidius]

Jet engine emissions and vapor contrail reduction through
increased combustion efficiency with the aim to mitigate greenhouse gas emissions.

https://digitalcommons.georgiasouthern.edu/cgi/viewcontent.cgi?article=1782&context=honors-theses

We don't know what are the type of the engine on the B-21

 

[Foo Fighter]

Not saying I do.