Ok i found the problem i have provided a snapshot.

 

The flashing A only happens at thrust reduction height 1500 and when N1 engages. its seems the command V2 speed bug (154) is in the yellow strip and this causes the A to flash.

 

i done another takeoff this time setting the speed bug at (160) and at 1500 no flashing A as the speed bug 160 wasn't in the yellow tape.

 

 

https://www.dropbox.com/s/f8dmgktd88d7ojg/2014-9-4_10-46-27-9.BMP?dl=0

 

If everything is correct, you shouldn't be in the amber band. Maybe you are rotating too aggressively?

2.5 degree a second my rotations are smooth to avoid tail strike!

The amber band doesn't kick in till N1 engages! So its not rotation.

 

Bloody doing my head in

Found this

 

http://forum.avsim.net/topic/398215-assumed-temp-takeoff-v2/page-2

 

I need to select a pitch mode to cancel out TOGA and then the speed bug is out of the amber band but at the V2 + 20

 

Boooom problem solved by a simmer lol

I think that what you described occurs on the NGX regardless of whether you select assumed termperature reduced thrust or not. The reason that the bugged V2 speed is in the amber band is that the top of the amber band (when flaps are extended) shows the speed where you have 1.3 g's (which is 40 degrees of bank angle) maneuver capability to stick shaker. V2 speed only provides 30 degrees of bank maneuver capability to stick shaker, which would be in the middle of the amber band.

 

Now, the question is whether you should ever see the amber band and V2 at the same time (as well as get an underspeed limiting indication on the mode control panel). According to page 10.11.9 of Vol 2 of the FCOM, the amber band should be inhibited on takeoff until the first flap retraction. So, you should never see what you are seeing because you would select a higher speed before retracting the flaps, and the amber band should not appear until you retract the flaps.

 

It would be nice if a real world pilot would confirm this, but I suspect that the NGX is not true to the airplane in this regard.

According to page 10.11.9 of Vol 2 of the FCOM, the amber band should be inhibited on takeoff until the first flap retraction. So, you should never see what you are seeing because you would select a higher speed before retracting the flaps, and the amber band should not appear until you retract the flaps.

 

So what you're saying is that you're seeing the amber band appear without having ever touched the flaps at all?

It looks like the airplane is heavier than it thinks it is.  Have you checked that your ZFW on the PERF INIT page is correct and matches the weight you have on the FS actions payload page?

Kyle that was just a quote from the link above!

 

Joe all my weights match and in KG

 

The amber band appears when N1 engages at thrust reduction height

FMC VSPEEDS match that of TOPCAT except for V1 which with TOPCAT its always a knot out compared to the FMC V1. I use V1 TOPCAT calculation !

 

All weights are in KG

 

All weights match

The N1 button should really change anything as far as this goes.

Ok done another flight and topcat gave me a flaps 25 takeoff and my V2 was out of the amber band.

 

well on this soon as thrust reduction kicks in and N1 the amber band appears

 

 

 

https://www.dropbox.com/s/554uigc2dajlmb2/2014-9-4_19-52-30-223.BMP?dl=0

quick question on retracting flaps its says at V2 + 15 retract does this mean when your speed gets to V2 + 15 or when you start to accelarate?

 

 

at V2 + 15 retract

 

It means "at V2 + 15 retract" your flaps.  Exactly as it says.  How could you interpret that otherwise?  Again, I really think it's a matter of how you're interpreting and operating things here, particularly based on your question.

 

If I said "rotate at Vr" does that mean when your speed gets to Vr, or when you hit TO/GA?  :wink:

Kyle this is why i got confused please read this i got it from a 737 NG PILOT 

 

Just as clarification to the previous comprehensive replies, there is no '-5' speed displayed after a flap 5 takeoff, only '-1' and '-UP'. Retraction from 5 to 1 can be initiated above V2+15 (the "white bug") and accelerating.

Similar for a flap 15 departure: Retract from 15 to 5 when above V2+15 (and accelerating), 5 to 1 at '-5' and 1 to Up at '-1'. 

A flap 1 takeoff is slightly different, retract from 1 to Up passing '-1'.

Reference: FCTM, 3.26.

Regards,
PA28pilot (who also flies 737s!)

 

Now he does say 'AND ACCELERATING' but your not ACCELERATING you are holding V2 + 20 only till you are at AA and ACCELERATING you can retract ?

 

I can interpret very well but reading it from a RW pilot i think i know what to go for.

 

 

Now he does say 'AND ACCELERATING' but your not ACCELERATING you are holding V2 + 20 only till you are at AA and ACCELERATING you can retract ?

 

Hold V2 + additive until accel altitude.  Select the next higher speed and pitch over at accel altitude.  Once you're aimed for that speed, retract the flaps when above V2 + 15 and accelerating.

so once you hit V2 + 20 retract the first flap setting what ever that is on flap table then once at AA retract on schedule?

But you can see where i got confused yeh? lol

first time i had a F25 its some what different to your F1 and 2 setting. feels like i just glided up with less pitch runway was only 1700 feet and i was pretty heavy and light winds.

 

I noticed on my FMC that my TOW doesn't reduce but the GW does on the TAKEOFF page. image below -

 

https://www.dropbox.com/s/14yfp3unnige10o/2014-9-4_10-41-38-213.BMP?dl=0

 

 

so once you hit V2 + 20 retract the first flap setting what ever that is on flap table then once at AA retract on schedule?

 

No.  Once you reach acceleration altitude and your speed is greater than V2+15 you begin the flap retraction.  The flight director in TOGA is going to command V2+20 so you should be above V2+15 upon reaching acceleration altitude so it's usually one call "VNAV, flaps xx".  It's important to verify you are above V2+15 before you begin your flap retraction because if you lose an engine on takeoff your speed will almost certainly be less than V2+15 and you need to accelerate, with two engines it's not a problem.

Right so what i mentioned before i was right then? Hold V2 + 20 untill AA then retract on schedule once A/C is accelarating?

 

 

I found this about V2 + 15 from RW pilot

 

It is to do with manoeuvre margin. If you are slower than V2 + 15kts you do not have the required overbank protection, hence if you have an engine failure on takeoff your initial speed target is V2 to V2 + 20kts. If you are at anything below V2 + 15kts then you do not have the required overbank protection and hence the 'blanket' rule that any initial turn is limited to 15 degrees AOB.

Received this email from an AVSIM member about the flashing A problem and its a NGX bug. He submitted a ticket.

 

 

Yes, it does happen on my 737NGX. It does not happen in the real airplane. The lower amber band should not appear until the first flap retraction.

I brought this to PMDG's attention back in Jan 2013. They confirmed the problem is there and said they would correct it.