B767 STAB Trim

[plt4u]

Where do operators reset the STAB trim on the B767 after landing? Is there any Boeing requirement to reset to a particular STAB setting after landing or prior to shutdown?? I hear some reset to a 2 degree position some reset to 4 degrees.
Thanks for the info

[Bullethead]

G'day plt4u,

I've been flying B767-2/300s for around seven years now and for normal operations there is no requirement to re-set the stab trim after landing or prior to sutdown.

Some operators set full nose down stab if the aeroplane is going to be parked in freezing conditions for any length of time.

Regards,
BH.

[plt4u]

Thanks BH, this is what I was thinking, no requirement to reset.

I still hope I get more opinions

[luvly jubbly]

Before GSM went bust, we reset the B767 stab trim to 2 degrees, and the B757 to 4 degrees. Although, looking through the FCOM for both After Landing & Shutdown/Secure procedures, setting stab trim is not a requirement. Maybe it's just a request from maintenance, or if you're multi fleet, it might just be for commonality between checklists.

The full nose down trim in icing was a requirement on the B737. This comes from a Boeing FCOM Bulletin.

LJ

[Spooky 2]

Resetting the stab trim after landing is not a Boeing procedure, however many operators will reset it to 4 degrees. This in turn matches the reference stripe on the outside of the aircraft next to the leading edge of the stab, thus allowing the pilot doing the walk around to see if the stab at 4 matches the stab trim setting inside the aircraft. I think this is more of a tribal knowledge type of a procedure than anything else.

[hector]

Agree with Spooky about the black strip on the fuselage corresponding to 4 on the trim indicator and that it's one of these practices passed down through the generations.

Quick question though. I've always seen it referred to as "units" of trim so do the units equate to degrees or does it just look like that?

[Spooky 2]

Hector you are absolutely correct about the "units" as they are in fact not degrees. They could have probably called them just about anything but in Boeing speak they are "units". Thanks for keeping me honest!

[plt4u]

Thanks for all of the replies/opinions. It is units not degrees. Thanks

[mono]

Re-setting the stab to neutral (4 units on the 75 and 2 units on the 76) was SOP in my company prior to merger. Post merger this has been stopped. There were two reasons for the practice:-

1. during the pdi a quick check could be made to confirm stab position against indication in the cockpit (the neutral position aligns with the stab marker on the fuselage)

2. In the event that the stab position was forgotten during pre departure checks the stab was already in a fairly neutral position and therefore it was unlikely to over rotate and tail strike. (the stab position after landing is always "aircraft nose up" WRT neutral but also quite often it's still within the TO warning green band so there is no aural warning WRT a/c configuration, BUT the a/c may tend to over rotate due to the already nose up position of the stab)

My tuppence worth is that it is a potential hole in the cheese. But what do I know huh?

[bumba]

Boeing Service Bulletin

mono

76 2 units nose-up before or after the Boeing Service Bulletin 767-27-0052 (Flight Controls - Elevator - Outboard Elevator Downrig Deletion)?

[mono]

Bumba,

I have no idea, every 76 I have worked had the neutral marker at 2 units and I am not aware of the SB state of all of them. 2 units btw is roughly the point at which the manual electric trim limit swtch activates (on the 767)