CRJ-700/900 Tailcone

[Check Airman]

Hello all,

To the CRJ pilots, or anyone else in the know, why do the 700 and 900 series aircraft have a black tailcone? What can't this area be painted?

http://www.airliners.net/open.file/1276639/L/

http://www.airliners.net/open.file/1276563/L/

[CRJ2]

On the CRJ700/900 the tailcone is also the APU-outlet!
This is the reason why the tailcone is not painted.
On the CRJ100/200 the APU-outlet is on the right side under the engine...

[Check Airman]

Thanks CRJ2.

Your answer seems obvious, but I'm still a bit puzzled. Other aircraft have a much smaller unpainted area back there. Thanks anyhow!

[sinkingship]

As stated it to do with the APU outlet exhaust, which is of a higher temp than the fuselage skin. Its to do with material spec, I'm sure if you look at other aircraft types the APU outlets are also unpainted, its just the CRJ stands out more.

[Check Airman]

OK. Thanks for the replies.