Hi guys!I was watching a DVD of Helios Airways and i just seen an interesting thing i didnt know up to now.If u select heading greater than 180 degrees lets say the left direction the airplane start the turn to left instead to the right.Did u know that???Is it the same in the Flight Sim as well?Cheers guys

Well give it a try.............................;)[h4]Best Wishes,Randy J. Smithhttp://img.villagephotos.com/p/2003-5/196432/winglets_lg.jpg

This behavior was common with the legacy flight directors. But I'm surprised that The Next Generation avionics package in an aircraft like the 737TNG would not have the logic to know when the heading bug was moved through 180 degrees and then turn the aircraft the direction that the bug was moved initially. I'm most familiar with the Collins Proline 21 'glass cockpit" avionics marketed for general aviation aircraft and it contains the logic to recognize this condition. Sometimes controllers issue a heading and ask that you make the turn the long way around. It was always a hassle to have to walk the heading bug around the compass rose keeping it on the correct side of 180 degrees of turn so the aircraft wouldn't bank off in the opposite direction. Hence the change in design philosophy in the modern flight directors.I'm sure that if this type of logic exists in the RW 737TNG and it and it was possible to model it in MSFS, the PMDG Team would include it.Hank RochonRegistered Owner

Hello Hank,Are you sure? Actually, this feature is installed on 737NG's (I think on PG's as well).IzAlso Registered Owner

As I stated, I'm not familiar with the flight director in the 737NG. However since it is a recent product, I would expect that it would have the logic to properly follow the heading bug when it is moved past 180 degrees of heading change. (past the tail of the aircraft) It was the older equipment that would not allow more than 180 degrees of heading bug movement without confusing the flight director.BTW - What's a PG? You can see I'm a Boeing newbie.Cheers,Hank RochonRegistered Owner

According to the Bulfer books, on the non-EFIS 737's, the airplane turns in the nearest direction. On the EFIS-equipped 737's (including all 737 NG's), the airplane will turn in the direction of initial knob movement.Although I haven't tried it in the PMDG sim, based on Randy's response, I'm sure it turns in the direction of inital knob movement.I wonder how many 737 NG pilots stagger their heading selection when making more than a 180 degree heading change to ensure that the airplane goes in the intended direction?Don S.

Well, it is not necessary to stagger your heading bug, as I said, except when you're not in HDG SEL when you turn the knob. If you're in LNAV and you want to make a 270degree turn to the left, turning the knob 270degrees left, and then selecting HDG SEL will make the airplane turn right.So, select HDG SEL first and then turn the knob all the way around.