Would could be the reason, that the 2 throttle levers are at different positions? Also one pair of engine gauges (3rd from the bottom) does not show identical values.http://www.airliners.net/open.file?id=713948Wolfgang

Engines are not identical, so depending on age and wear and other factors they may show slightly different parameters. The throttle levers are probably set like that to match thrust between them.-

There are a few reasons for the discrepancies here. One would be that one of the engines is newer and developing more thrust in cruise while the older engine requires a higher throttle lever position to develop the same EPR. Another reason would be the engine trimming in where the fuel control is adjusted to bring the power levers into allignment. Another could be a mix of engines. Maybe a JT8D-9 with a -15. The gauge you refer to is the EGT and seeing that the rest of the parameters are normal, I would say the the #2 engine is nearing the end of its life or there is an engine mix installed on this aircraft. BTW, a half knob throttle split is not that uncommon for a JT8 engine installation.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.precisionmanuals.com/images/forum/ng_driver.jpg

Thanks for your interesting explanations, guys!Wolfgang

Another reason could also be throttle cable rig. Since there are cables running all the way from the throttle quadrant to the engine, through pulleys and bellcranks, it doesn't take much to throw off the settings. Back when I worked for a major US carrier, we got some planes from PanAm that were in bad shape, especially the 747s. The throttles would be all over the place when putting out equal power.

Last reason might be extreme crosswind. Using some differential thrust would keep the aircraft stable if control input alone were insufficient.

< Last reason might be extreme crosswind. Using some differential thrust would keep the aircraft stable if control input alone were insufficient. >How did you come to this conclusion? :-rollA half knob split is within limits.First indication would be a eng. inter-mix, which there should be a placard above each eng. indicating stack and front and inside cover of the a/c log book showing the inter-mix type.Eng. F/F will tell the whole story. I can not see it in this pic though. #2 EGT appears a bit higher than #1, the other ind. appear matched. If the #2 eng has high fuel consumption, you will see higher EGT. Most likely a tired eng.