F-15 nozzles - dissimilar when shut down?

[LanceB]

Apologies if this was covered somewhere and I just can't find it, but I was looking at this set:

 

http://www.armahobby.com/f-16-pw229-engine-nozzle.html

 

And the thought occurred to me - we all know that F-14 nozzles are normally seen in "closed" and "open" positions when parked, from my limited experience usually port closed and starboard open, due to the effects of shutting down one engine while taxiing in from the runway on the other and then the hydraulics not having time to close the starboard nozzle before losing pressure on shutdown.  Does this happen on F-15s as well, so that this Arma Hobby set would be good for a set of nozzles for 1 F-15 with turkey feathers?  And if so, is there any general rule of thumb about which afterburner can is the more "relaxed" on shut-down?

[habu2]

I have photos of parked F-15s with one nozzle open, the other closed.  Not at home to upload them right now....

[Parabat]

Indeed, not the typical state, but not unheard of or impossible.

[Falconxlvi]

Normal shutdown leaves both nozzles fully open.   Usually there was a problem with the DEEC if the nozzle was still closed after shutdown.   

[Ol Crew Dog]

The nozzles would not normally be dissimilar, unless an emergency shutdown, out of rig or malfunction with the EEC, DEEC, nozzle actuator or any linkage cabling controlling the nozzle. Hopefully this occurs during a ground run due to if it happens inflight there would be a chance of a burn threw or blow out occurring. We had to scavenge the engines on ground runs  to prevent oil leakage in the bearings, depending on how this is done by the operator could leave the nozzles in an asymmetric state as the are actuated through fuel and mechanical means. A scavenge is pushing the throttle to close to mil power and holding for 5 seconds and snap the throttle to cut off. The nozzles are rigged to go to a default open position so when shutdown they should automatically go to open position. Sorry about the drawn out answer but hope it  Helps. 

[habu2]

Taken at Scott AFB, circa 2003, jet was either 75-0065 or 76-0112

 

 

 

 

 

 

Edited January 6, 2017 by habu2

[DonSS3]

[Ol Crew Dog]

You can tell that #1 was shutdoen first and number 2 was above idle prior to shutdown in the first three pictures. They all have EECs and not DEECs, EECs are Electronis Exhaust Controllers and the DEEC was the Digital fitted on later model engines and E models. DEECs have allot faster reaction to throttle movement, EECs are not the fast and thus on shutdown it would reflect that. If both engines were shutdown straight from idle and with gravity affecting the Div and Con  seals they would be slightly different.

[LanceB]

Thanks for all the detailed replies - so the takeaway is "not really normal, but not really wrong".  Seeing as this set has nicely-detailed nozzles with feathers, which is just what I need for an F-15A project, and using them is a WHOLE lot simpler than the other option I was looking at for putting feathered exhausts on the Hasegawa kit, I guess I shall use them.

[Ol Crew Dog]

55 minutes ago, LanceB said:

Thanks for all the detailed replies - so the takeaway is "not really normal, but not really wrong".  Seeing as this set has nicely-detailed nozzles with feathers, which is just what I need for an F-15A project, and using them is a WHOLE lot simpler than the other option I was looking at for putting feathered exhausts on the Hasegawa kit, I guess I shall use them.

Goes without saying, one time I cut the rudders on an f-15 kit and splayed the left one to port and the right one to starboard. I entered it into a local contest and was told it wasn't possible! Well a month or 2 prior, one  morning went out to my jet and there was a good  wind the night before and my jets rudders were played that way, took a picture and had it handy for that contest. 

 

[JeffreyK]

Note that the point of this set by Arma/Attack is not to show dissimilar nozzles, but to depict one open powered engine nozzle (idle or AB) and an open nozzle after resting where the top petals are slightly more closed from idle and the bottom petals sagged down, making the nozzle in itself asymmetrical, as evidenced in some of the photos above. Clever idea, I have actually been thinking about the same thing for another application...

 

Jeffrey