737NGX is a dream and hard to control

[Michael Moe 494]

Well i must say that this has been my best experience overall in flight simulation at all and i want to say that is has been a big step in my own evaluation of being a flight simulator user . afterall the Maddog is not the king any more.. Neverless i am a simulator and not a pilot so please give me a chance afterall i do not have AOA video yet :-) What is on my mind is takeoff, I find my self often after V2 and in air the N1 has the speed pile down instead of up . Can a reel pilot or a bright fellow explain what they do just after V2 ? Thanks Michael

[rocketfs 2]

Sorry man, willing to help but we need a question a bit more specific? Bert Van Bulck

[badderjet 181]

If you need the speed trend vector, and it pointing down, then you're obviously decelerating. That could be a good or a bad thing depending on your current speed. However, as long as everything has been set up properly before departure, following the FD bars should usually put you in a safe condition after liftoff and not result in any significant speed change at first.

[Ken737 1]

Are you asking about takeoff procedures? A lot of good information is in the FCTM.

[Guest firehawk44]

Well i must say that this has been my best experience overall in flight simulation at all and i want to say that is has been a big step in my own evaluation of being a flight simulator user . afterall the Maddog is not the king any more.. Neverless i am a simulator and not a pilot so please give me a chance afterall i do not have AOA video yet :-) What is on my mind is takeoff, I find my self often after V2 and in air the N1 has the speed pile down instead of up . Can a reel pilot or a bright fellow explain what they do just after V2 ? Thanks Michael

Move the throttle all the way up after you enable N1. The FMC will take over once the CMD is enabled. Best regards,Jim Young

[Michael Moe 494]

Thanks guys :-) Well i believe it is something like this, After leaving the rwy at say 149knot my FD will help me speed up to safety V2+20 (169knots) and i am flying in TO/GA mode. Now if i stay with the FD i should be at 169 knots with the speedbug present right? I can see that i am in N1 because this is armed before takeoff with the autothrust and TOGA button right ? What strange is that if i hit the CMD button it would slow down and the white speedarrow will point down . The MCP always blink A149 or 169 i cant remember. and i have sometimes getting closed to V2 speed before i switch then MCP to say 200knots. This would speed up the engines. Is it because i dont understand the acc height maybe or maybe because i am in TO/GA mode ? Thanks Michael

[neas1982 42]

Hi Michael, After you hit the CMD button, the TO/GA mode will revert to whatever vertical profile mode you have selected, this can be V/S, LVL CHG, or VNAV. Best thing to do is to select one of these modes before you engage CMD at your accel ht., handfly it for a while untill you are at a comfortable speed and in a nice climb and then hit CMD or arm VNAV on the ground and then at your selected accel ht the TO/GA mode will automatically revert to VNAV Kind Regards,Sean

[Michael Moe 494]

Thanks , I found maybe the reason as you say in the FCTM page 133 it goes like this Note : If the autopilot is engaged prior to engaging VNAV, the autopilot engages in LVL CHG and the FMA pitch mode changes to MCP SPD unless another pitch mode has been selected Thats it, the speed in MCP is the V2 speed i think (149knots) which is slowing down the plane hitting the CMD after takeoff The FCTM says very different stuff about VNAV . Best selected before rwy leaving and engaged (with the CMD?) after flaps retraction? How is that possible if i engage the Autopilot at 500 feet?

[badderjet 181]

Now if i stay with the FD i should be at 169 knots with the speedbug present right?

No. The speedbug doesn't change. FDs will however command V₂+20, but this is neither reflected on the MCP nor the speed bug.

Thats it, the speed in MCP is the V2 speed i think (149knots) which is slowing down the plane hitting the CMD after takeoff

No, when you engage CMD with no other modes selected it will go to LVL CHG at V₂+20, and this is immediately reflected on the speed bug and MCP. If you correctly maintained V₂+20 after takeoff by following the FD precisely there should not be any speed change whatsoever until that point. Then you can either reset your speed to bug up for example or engage another pitch mode.

The FCTM says very different stuff about VNAV . Best selected before rwy leaving and engaged (with the CMD?) after flaps retraction? How is that possible if i engage the Autopilot at 500 feet?

You never engage VNAV on ground. Watch your FMA - it would never engage. You can arm it, and if you opt to do so it will engage automatically when passing 400R. CMD can be selected on by that altitude as well.

[Michael Moe 494]

Thanks for the fine explanation, Why is it i often see the "A" on the MCP speed panel? (A169 for instance)? If you want to handfly this bird up to clean flaps at say 3000feet and the acc height is 1500 feet what would be the scenarie? Would it stay in TO/GA and N1 up to a change at 3000feet? Also i find this a little difficult to understand (reduction height and acceleration height) /Michael

[neas1982 42]

Hi Michael, You would arm VNAV on the ground, if you wnat together with LNAV. Yo would program the FMC for reduction alt of 1500ft (where you thrust setting will go from TO to CLB mode) and your accel height at 3000ft (where you would start to accelerate to 250 knots, retracting flaps in the process). After take off at 400 ft VNAV will "engage", it will drive the pitch bar of the F/D. The only think you have to do is follow the Flight Director now, handfly as long as you want, and engage CMD whenever you want. Normally your NG will now accelerate to 250 knots below 10000ft and optimum climb speed above 10000ft. Grtz,Sean

[badderjet 181]

The A is the underspeed limiting symbol. It shows up whenever the speed cannot be reached. Read on FCOM Vol II 4.20.31 for further information. The counterpiece would be overspeed limit, which is symbolized by an 8. In either case you have to redial the speed and to get rid of the symbol you need to get at least 15 knots away from the limiting speed.