Currently I have to perform a check ride with a virtual airline where I am not permitted to engage the A/P below 10,000 ft. 

 

My takeoff procedure is as follows:

 

• Arm A/T L and R
• Set MCP Speed to V2
• Advance throttles to 55%
• Press TO/GA
• Wait until THR REF is annunciated on the FMA
• Push the throttles full forward.

 

Now, based upon my reading/research the A/T and the A/P systems are independent.  So, after wheels up, I expected the airplane to not exceed V2 on climb out.  However, within about two to three seconds I am way up in the mid 300's ... a gross overs speed event.  A/T are definitely engaged but I'm not seeing what I expect with regards to the MCP Speed setting.  I searched the manuals but all I found were instructions where the assumption is being made that the A/P button is engaged above 200'/400' AGL.  I wonder if I have to engage a pitch mode like FLCH ... even though A/P is not engaged?

 

I had to do the same thing in the 737NGX ... for the same airline ... and finally resorted to manually controlling the thrust throughout the climb out.

 

Thanks,

Two things control your speed: thrust and attitude. In THR REF thrust is commanded to the reference N1; speed control is then up to you to control with pitch. Assuming you've got the flight directors on, they'll guide you to fly V2 + 20 (+/- 5).

You need to adjust your pitch to keep the speed fixed during the climbout. Below the thrust reduction altitude the power will remain constant, so you have to increase your pitch to prevent additional acceleration. 

 

If you arm VNAV before takeoff this will engage and set the increased speeds as you pass the thrust reduction altitude based on your flap position, and as a result the flight director will be providing you pitch guidance to remain at these speeds. All of this is independent of the autopilot.

 

Kevin Roche

I had to do the same thing in the 737NGX ... for the same airline ... and finally resorted to manually controlling the thrust throughout the climb out.

 

You're treating the plane like most simmers do.  The simple answer is: don't treat it like a simmer treats it.

 

I'll be honest, I did the same thing when I started flying jets in flight sim.  I'd take off, engage A/T, set the speed in the window to 250, and then adjust the VS to some arbitrary value.  This is not correct per most aircraft's climb profile.

 

What you should be doing is the following:

• Arm A/T L and R (this switch should always remain in the on position unless specifically told to turn it off, which is only in non-normal procedures)
• Set MCP Speed to V2
• Advance throttles to 55%
• Press TO/GA
• Advance the hardware throttles to match where the A/T is placing them (this can be helped using the "show hardware position" option)
• Wait until THR REF is annunciated on the FMA
• Push the throttles full forward.
• Pitch to maintain V2+10 (I believe up to 20 is acceptable per the FCOM) - follow the flight director cue
• The flight director will then command a pitch decrease at reduction to CLB(-1/2) thrust (may coincide with next item)
• The flight director will then command a pitch decrease at accel height to allow an acceleration to 250
• These procedures will often result in high vertical speeds that will make most simmers (and VA/FSPax programs) believe they are torturing their passengers.  This is not true, and is only a simism.  If it really bothers you, use derates combined with assumed temps to temper your climb.

The FCTM describes this procedure in greater detail.

 

 

 

This is a simulation of the real aircraft.  As such, it should be flown using the procedures for the real aircraft if you're expecting it to behave like the real aircraft.  In order to help further illustrate the profile, the profile is explained (somewhat) graphically on page 3.2.

 

The long and short of it is:

Use pitch to adjust/hold your airspeed.

• Pitch to maintain V2+10 (I believe up to 20 is acceptable per the FCOM) - follow the flight director cue
• The flight director will then command a pitch decrease at reduction to CLB(-1/2) thrust (may coincide with next item)
• The flight director will then command a pitch decrease at accel height to allow an acceleration to 250

 

Just to clarify that the last 2 points above assume you've armed VNAV, otherwise you'll simply stay in TOGA.

 

The F/D will command between V2 +15 and V2 + 25, depending on what speed your speed is after rotation. Usually V2 + 25 with those engines, I find!

Perfect ... I have to apologize ... this is exactly how I completed the check ride in the 737 ... it was so long ago I forgot about the pitch solution to the problem. 

 

Kyle ... gotta love that signature ...

 

 

Kyle ... gotta love that signature ...

 

haha - thanks.

 

Glad we could help, in any case!

It's a good thing I'm not a real pilot ... I'd be at the pearly gates with my FO, Bob, talking to St. Peter

 

Me:  D*#n ... that's what I should have done ... Bob ... don't you remember we performed that procedure on approach at KSFO and things worked out swimmingly? 

 

Bob:  ... glaring ... menacingly ...

Derate your takeoff heavily and climb too, that way you wont be having to deal with so much thrust

I have to say ... if this plane is modeled as accurately as PMDG claims ... then those engines are unbelievably powerful ... I want one in my Infiniti I30t .. or ... as it is known with this mod ... Infiniti I30XL.

 

 

It's a good thing I'm not a real pilot ... I'd be at the pearly gates with my FO, Bob, talking to St. Peter

 

haha - that, or you would've just thought to use pitch out of habit.

 

They teach you "throttle for power, pitch for airspeed" very early on.

 

For me, it's almost automatic when I fly a 172 (the other aircraft I fly will require a brush up on the speeds next time I take them up).

Airspeed alive

55, rotate

Pitch for 70

Adjust pitch for 80 when practical

 

...but again, it's all habit by now for a takeoff/climb procedure to use pitch for airspeed.

I'm still running flap 5 and a derate of around 60°C assumed temperature and climb derate 1 for a trans atlantic.

 

The 77L thinks that an 8 hour flight from the USA to Europe is just a light jaunt around the block.

 

When I'm doing 1 hour flights like Japan Domestic flights or some of the shorter Freighter legs, ... Derate 75°C otherwise you're rotating before you pass 1000ft down the runway and climbout is bigger than 20° nose up pitch.

 

Yes, those engines are huge power beasts.

 

Remember it needs to get a 16 hour trip fuel load, Maximum ZFW off the ground from V1 with just 1 engine running ;-)

(and manage to actually climb out of ground effect at about 3% climb gradient.)