N1 Button

[tman41291 4]

So after a search of the forums i found a thread discussing this, but after seeing someone get bashed for resurrecting an old thread, I decided to start another. My question is about the N1 button on the MCP. I am curious as to how it is properly used. I understand different situations dictate the use of certain things, so examples of real world scenarios would be appreciated. From my brief understanding of it all, the button is pressed then the speed bug is moved to flaps up speed, as the button initiates the change from t/o thrust to climb thrust. It is also from my understanding (now i may be getting this misunderstood with airbus) that you can program when the aircraft switches from t/o thrust to climb thrust in the FMC when reaching acc. height...so thats why the question arises of which scenarios would dictate the use the button if the FMC can just be programmed to do it for you?

[JoeDiamond 67]

I don't think I've ever actually touched that button in the real airplane.  We select VNAV at 1000' AFL which takes care of the thrust modes.  We have no normal procedure that calls for the use of the N1 button on the MCP. 

[skelsey 765]

I am not particularly conversant with the 737 bit from the descriptions above it sounds as though the N1 button on the NG is broadly comparable to the THR button on the 744: it makes the wings fall off (ie there's little practical use for it and nobody understands properly what it does so nobody touches it!)

[Spin737 102]

Used it for years. Instead of VNAV, you'd start in TOGA mode, then the call was "Bug UP, N1, Flaps 1." We would then clean up and switch to VNAV.

I think it was initially for harmonization between the 737CL and the 737NG fleets and U10.7.

Don't worry about the N1 button. It's vestigial, mostly.

[tman41291 4]

Thank you everyone!

[Stearmandriver 2,237]

What Spin said.   The "bug up,  N1, Flaps 1" approach can still be useful if you decide you want to climb at clean maneuver speed for a while; climbing under class B, wanting to wait until pointed in the right direction to accelerate etc.   Then just call for Vnav when ready to accelerate.   'Course you could program it in the box too,  then just call for Econ Climb when ready to accelerate... just different ways to skin the cat..