Manual Setting of Vref?

[Guest tmetzinger]

Hi Guys,working on the tutorial, in the first flight the trainee never touches the FMC, but sets V speeds manually. I've run into the following problems:Setting the bugs for V1 and VR work correctly, but there's no callout as those speeds are reached (no biggy).Once in flight, I make a big circuit at 2500 feet and attempt to set Vref manually - no luck. On the approach the FMC alert light comes on cause it's not set.Can you check this functionality? If Vref setting doesn't work, I can teach around it. But if it does work, I need to know what I'm doing wrong.

[Guest tmetzinger]

bump

[Guest tmetzinger]

bumpity bump

[Jet Tech 31]

Tim,Talked to Lefteris and we will look at this for the 800/900. Appears to broke at this time. Get out the MEL Book :-)RegardsPaul Gollnick :-cool Technical Operations/Customer Operational SupportPrecision Manuals Development Groupwww.precisionmanuals.comhttp://www.precisionmanuals.com/images/forum/devteam.jpg

[Guest tmetzinger]

>Tim,>Talked to Lefteris and we will look at this for the 800/900. >Appears to broke at this time. Get out the MEL Book :-)>Regards>Paul Gollnick :-cool Thanks, Paul... always glad to know it's not pilot error. On a related note, how can one determine Vref without the FMC? I didn't see anything in the AOM on calculating Vref, only on runway length, etc.

[Jet Tech 31]

Tim,You would have to get a hold of a set of Landing or Take-off number Flip cards. They would give you the various numbers for different weights and flap settings. As far as determining which flap setting to use with which runway. Have to ask your dispatcher :-)RegardsPaul Gollnick :-cool Technical Operations/Customer Operational SupportPrecision Manuals Development Groupwww.precisionmanuals.comhttp://www.precisionmanuals.com/images/forum/devteam.jpg

[Jim Harnes 13]

Tim,This is from Matt Zagoren's B737-700 Performance and Selected Limitations, CFM56-7B20:737-700 Vref FLAPSWEIGHT 40 30 15 1000KG)80 154 156 16275 149 151 15770 144 146 15265 139 141 14760 133 135 14055 127 129 13450 120 123 12745 114 117 121For approach speed add wind factor of 1/2 the headwind component+ gust (max 20 knots)Jim Harnes

[Guest tmetzinger]

>Tim,>>This is from Matt Zagoren's B737-700 Performance and Selected>Limitations, CFM56-7B20:>>737-700 Vref FLAPS>>WEIGHT 40 30 15 > >1000KG)>80 154 156 162>75 149 151 157>70 144 146 152>65 139 141 147>60 133 135 140>55 127 129 134>50 120 123 127>45 114 117 121>>For approach speed add wind factor of 1/2 the headwind>component>+ gust (max 20 knots)>>Jim HarnesMuch appreciated - I'll put this in a nice table and add it to the tutorial package.