OK fellas, it's Sinbad again.I have been able to find out what the LRC function is through a search on this forum. I have not been able to discover what the flap/spd function on the APP REF page does or about the ECON or ENG OUT blocks on the VNAV page. Have I missed something in the manual or is it like the LRC function and not implemented?You all have been a great help by the way. I appreciate it.ThanksSinbad

LRC = long range cruise (I think), giving a speed to maximize cruise range. I don't know if it is implemented. I never want to go that slow.Flaps/Speed on APP REF page is where you select which flap setting you will be using. The Speed is Vref, the reference speed which is basically the touchdown speed. Approach speed with generally be between Vref +5 and Vref + 20 depending on wind gusts.ECON select the best econonmy airspeed.ENG OUT selects the best speed for single engine out.Lee Hetherington (KBED)

Thanks Lee,I presume then that the flap speed cannot be entered until just before approach because weather and fuel burn off will dictate this speed. What is done with this entry? As far as ECON and ENG OUT speeds, how are these determined? I thought ECON speed was already calculated on the VNAV page. Is this the same speed and just requires entry in this slot also? Apparently I need more information sources than the manual, how have you all figured this stuff out?Thanks for the help.Sinbad

Hi Sinbad.You can choose your landing flaps more or less as soon as you begin your descent since normally the engines are in flight idle during the descent and the amount of fuel that is burned until touchdown is seldom big enough to cause any big changes of the weight => ref speeds mentioned earlier. Obviously this depends on the descent profile, but it works as a general principle. Choose flap setting shortly after initiating the descent and check (update if necessary) when you

Standard procedure is to enter your landing weight in the APPROACH REF page, that will give you the correct VREF for landing.Lee, LRC is not slow at all. On our 757s, LRC was M.799, yes, sometimes higher than your ECON speed. This contrary to some other aircraft (not so well designed..) that have LRC speeds that are much slower, sometimes as slow as M.600.On 737NG, LRC will be around M.770 at optimum flight level.Iz

Hello all,Thanks for all the help. That URL was also great with a lot of good info.Alas, due to circumstances beyond my control (read wife here), I am being forced to go on a two week vacation. The good news is you all will get one also..no more questions that probably seem silly.Again, thanks for all the help.I wish each and everyone of you a happy holiday and safe new year.Sinbadp.s. I'll be back with more questions, after all I'll have two weeks to come up with them.

Hi,If you look in the progress page in flight it will tell you fuel quantity on landing. Add this to your zero fuel weight and enter this figure as the landing weight in the approach page.The flap speeds are then shown appropriate to your landing weight.You can then set your bug speeds before the top of descent.I usually do the descent checks 15/20 mins before the tod to reduce the workload.RegardsSimmslot