[US Navy Vet]

Yep the F-22 yet ANOTHER GREAT Lockheed Martin Product, the USAF should have went w/ the F-23:
http://en.wikipedia.org/wiki/Northrop_YF-23

[GBA]

Would be an excellent true replacement for the F-14 and give the Navy their own 5th gen fighter.

Too good to let go to waste.

[tophat9000]

Ah the article is referring to potential an engine issues...so thats not Lockheed ...The AF chose the winning engine to put in the winning airframe so F-23 with same winning engine same problem....and if it is the oxygen system the from the F18 in large part a Northrup product

To be honest I do not see how this could be an engine issue...

But we could have a secret stealth fuel additive that they are not talking about that could be the real issue

In any jet exhaust you would have thing that would compromise stealth...smoke, heat, contrails...the left over exhaust gasses themself...all leave a trail to follow

These are all emission you would want to suppress in a "stealth" aircraft...

And that could be with a fuel additive and that could leave some poisonous exhaust gasses

[driftdiver]

It probably would have used the same oxygen generation system.

[mwilli20]

Hear, hear, from another YF-23 fan!!!

[fremont_steve]

This is better coverage of the topic - and more recent also from “Aviation Week and Space technology”

http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_07_2012_p31-454218.xml

Summary - They are now looking for other sources than air contaminants since the filters mentioned in the original poster’s article didn’t have anything glaring show up.